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Sample records for semantic dementia show

  1. Preserved musical semantic memory in semantic dementia.

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    Weinstein, Jessica; Koenig, Phyllis; Gunawardena, Delani; McMillan, Corey; Bonner, Michael; Grossman, Murray

    2011-02-01

    To understand the scope of semantic impairment in semantic dementia. Case study. Academic medical center. A man with semantic dementia, as demonstrated by clinical, neuropsychological, and imaging studies. Music performance and magnetic resonance imaging results. Despite profoundly impaired semantic memory for words and objects due to left temporal lobe atrophy, this semiprofessional musician was creative and expressive in demonstrating preserved musical knowledge. Long-term representations of words and objects in semantic memory may be dissociated from meaningful knowledge in other domains, such as music.

  2. Discovering EEG resting state alterations of semantic dementia.

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    Grieder, Matthias; Koenig, Thomas; Kinoshita, Toshihiko; Utsunomiya, Keita; Wahlund, Lars-Olof; Dierks, Thomas; Nishida, Keiichiro

    2016-05-01

    Diagnosis of semantic dementia relies on cost-intensive MRI or PET, although resting EEG markers of other dementias have been reported. Yet the view still holds that resting EEG in patients with semantic dementia is normal. However, studies using increasingly sophisticated EEG analysis methods have demonstrated that slightest alterations of functional brain states can be detected. We analyzed the common four resting EEG microstates (A, B, C, and D) of 8 patients with semantic dementia in comparison with 8 healthy controls and 8 patients with Alzheimer's disease. Topographical differences between the groups were found in microstate classes B and C, while microstate classes A and D were comparable. The data showed that the semantic dementia group had a peculiar microstate E, but the commonly found microstate C was lacking. Furthermore, the presence of microstate E was significantly correlated with lower MMSE and language scores. Alterations in resting EEG can be found in semantic dementia. Topographical shifts in microstate C might be related to semantic memory deficits. This is the first study that discovered resting state EEG abnormality in semantic dementia. The notion that resting EEG in this dementia subtype is normal has to be revised. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  3. Considering the role of semantic memory in episodic future thinking: evidence from semantic dementia.

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    Irish, Muireann; Addis, Donna Rose; Hodges, John R; Piguet, Olivier

    2012-07-01

    Semantic dementia is a progressive neurodegenerative condition characterized by the profound and amodal loss of semantic memory in the context of relatively preserved episodic memory. In contrast, patients with Alzheimer's disease typically display impairments in episodic memory, but with semantic deficits of a much lesser magnitude than in semantic dementia. Our understanding of episodic memory retrieval in these cohorts has greatly increased over the last decade, however, we know relatively little regarding the ability of these patients to imagine and describe possible future events, and whether episodic future thinking is mediated by divergent neural substrates contingent on dementia subtype. Here, we explored episodic future thinking in patients with semantic dementia (n=11) and Alzheimer's disease (n=11), in comparison with healthy control participants (n=10). Participants completed a battery of tests designed to probe episodic and semantic thinking across past and future conditions, as well as standardized tests of episodic and semantic memory. Further, all participants underwent magnetic resonance imaging. Despite their relatively intact episodic retrieval for recent past events, the semantic dementia cohort showed significant impairments for episodic future thinking. In contrast, the group with Alzheimer's disease showed parallel deficits across past and future episodic conditions. Voxel-based morphometry analyses confirmed that atrophy in the left inferior temporal gyrus and bilateral temporal poles, regions strongly implicated in semantic memory, correlated significantly with deficits in episodic future thinking in semantic dementia. Conversely, episodic future thinking performance in Alzheimer's disease correlated with atrophy in regions associated with episodic memory, namely the posterior cingulate, parahippocampal gyrus and frontal pole. These distinct neuroanatomical substrates contingent on dementia group were further qualified by correlational

  4. COTARD SYNDROME IN SEMANTIC DEMENTIA

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    Mendez, Mario F.; Ramírez-Bermúdez, Jesús

    2011-01-01

    Background Semantic dementia is a neurodegenerative disorder characterized by the loss of meaning of words or concepts. semantic dementia can offer potential insights into the mechanisms of content-specific delusions. Objective The authors present a rare case of semantic dementia with Cotard syndrome, a delusion characterized by nihilism or self-negation. Method The semantic deficits and other features of semantic dementia were evaluated in relation to the patient's Cotard syndrome. Results Mrs. A developed the delusional belief that she was wasting and dying. This occurred after she lost knowledge for her somatic discomforts and sensations and for the organs that were the source of these sensations. Her nihilistic beliefs appeared to emerge from her misunderstanding of her somatic sensations. Conclusion This unique patient suggests that a mechanism for Cotard syndrome is difficulty interpreting the nature and source of internal pains and sensations. We propose that loss of semantic knowledge about one's own body may lead to the delusion of nihilism or death. PMID:22054629

  5. Semantic dementia without surface dyslexia in Spanish: unimpaired reading with impaired semantics.

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    Wilson, Maximiliano A; Martínez-Cuitiño, Macarena

    2012-01-01

    Surface dyslexia has been attributed to an overreliance on the sub-lexical route for reading. Typically, surface dyslexic patients commit regularisation errors when reading irregular words. Also, semantic dementia has often been associated with surface dyslexia, leading to some explanations of the reading impairment that stress the role of semantics in irregular word reading. Nevertheless, some patients have been reported with unimpaired ability to read irregular words, even though they show severe comprehension impairment. We present the case of M.B., the first Spanish-speaking semantic dementia patient to be reported who shows unimpaired reading of non-words, regular words, and - most strikingly - irregular loan words. M.B. has severely impaired comprehension of the same words he reads correctly (whether regular or irregular). We argue that M.B.'s pattern of performance shows that irregular words can be correctly read even with impaired semantic knowledge corresponding to those words.

  6. Semantic Dementia Shows both Storage and Access Disorders of Semantic Memory

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    Yumi Takahashi

    2014-01-01

    Full Text Available Objective. Previous studies have shown that some patients with semantic dementia (SD have memory storage disorders, while others have access disorders. Here, we report three SD cases with both disorders. Methods. Ten pictures and ten words were prepared as visual stimuli to determine if the patients could correctly answer names and select pictures after hearing the names of items (Card Presentation Task, assessing memory storage disorder. In a second task, the viewing time was set at 20 or 300 msec (Momentary Presentation Task, evaluating memory access disorder using items for which correct answers were given in the first task. The results were compared with those for 6 patients with Alzheimer’s disease (AD. Results. The SD patients had lower scores than the AD group for both tasks, suggesting both storage and access disorders. The AD group had almost perfect scores on the Card Presentation Task but showed impairment on the Momentary Presentation Task, although to a lesser extent than the SD cases. Conclusions. These results suggest that SD patients have both storage and access disorders and have more severe access disorder than patients with AD.

  7. Magnetoencephalography of frontotemporal dementia: spatiotemporally localized changes during semantic decisions

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    Nestor, Peter J.; Hodges, John R.; Rowe, James B.

    2011-01-01

    Behavioural variant frontotemporal dementia is a neurodegenerative disorder with dysfunction and atrophy of the frontal lobes leading to changes in personality, behaviour, empathy, social conduct and insight, with relative preservation of language and memory. As novel treatments begin to emerge, biomarkers of frontotemporal dementia will become increasingly important, including functionally relevant neuroimaging indices of the neurophysiological basis of cognition. We used magnetoencephalography to examine behavioural variant frontotemporal dementia using a semantic decision task that elicits both frontal and temporal activity in healthy people. Twelve patients with behavioural variant frontotemporal dementia (age 50–75) and 16 matched controls made categorical semantic judgements about 400 pictures during continuous magnetoencephalography. Distributed source analysis was used to compare patients and controls. The patients had normal early responses to picture confrontation, indicating intact visual processing. However, a predominantly posterior set of regions including temporoparietal cortex showed reduced source activity 250–310 ms after stimulus onset, in proportion to behavioural measures of semantic association. In contrast, a left frontoparietal network showed reduced source activity at 550–650 ms, proportional to patients’ deficits in attention and orientation. This late deficit probably reflects impairment in the neural substrate of goal-oriented decision making. The results demonstrate behaviourally relevant neural correlates of semantic processing and decision making in behavioural variant frontotemporal dementia, and show for the first time that magnetoencephalography can be used to study cognitive systems in the context of frontotemporal dementia. PMID:21840892

  8. Personal Experience and Arithmetic Meaning in Semantic Dementia

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    Julien, Camille L.; Neary, David; Snowden, Julie S.

    2010-01-01

    Arithmetic skills are generally claimed to be preserved in semantic dementia (SD), suggesting functional independence of arithmetic knowledge from other aspects of semantic memory. However, in a recent case series analysis we showed that arithmetic performance in SD is not entirely normal. The finding of a direct association between severity of…

  9. Dementias show differential physiological responses to salient sounds.

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    Fletcher, Phillip D; Nicholas, Jennifer M; Shakespeare, Timothy J; Downey, Laura E; Golden, Hannah L; Agustus, Jennifer L; Clark, Camilla N; Mummery, Catherine J; Schott, Jonathan M; Crutch, Sebastian J; Warren, Jason D

    2015-01-01

    Abnormal responsiveness to salient sensory signals is often a prominent feature of dementia diseases, particularly the frontotemporal lobar degenerations, but has been little studied. Here we assessed processing of one important class of salient signals, looming sounds, in canonical dementia syndromes. We manipulated tones using intensity cues to create percepts of salient approaching ("looming") or less salient withdrawing sounds. Pupil dilatation responses and behavioral rating responses to these stimuli were compared in patients fulfilling consensus criteria for dementia syndromes (semantic dementia, n = 10; behavioral variant frontotemporal dementia, n = 16, progressive nonfluent aphasia, n = 12; amnestic Alzheimer's disease, n = 10) and a cohort of 26 healthy age-matched individuals. Approaching sounds were rated as more salient than withdrawing sounds by healthy older individuals but this behavioral response to salience did not differentiate healthy individuals from patients with dementia syndromes. Pupil responses to approaching sounds were greater than responses to withdrawing sounds in healthy older individuals and in patients with semantic dementia: this differential pupil response was reduced in patients with progressive nonfluent aphasia and Alzheimer's disease relative both to the healthy control and semantic dementia groups, and did not correlate with nonverbal auditory semantic function. Autonomic responses to auditory salience are differentially affected by dementias and may constitute a novel biomarker of these diseases.

  10. Dementias show differential physiological responses to salient sounds

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    Phillip David Fletcher

    2015-03-01

    Full Text Available Abnormal responsiveness to salient sensory signals is often a prominent feature of dementia diseases, particularly the frontotemporal lobar degenerations, but has been little studied. Here we assessed processing of one important class of salient signals, looming sounds, in canonical dementia syndromes. We manipulated tones using intensity cues to create percepts of salient approaching (‘looming’ or less salient withdrawing sounds. Pupil dilatation responses and behavioural rating responses to these stimuli were compared in patients fulfilling consensus criteria for dementia syndromes (semantic dementia, n=10; behavioural variant frontotemporal dementia, n=16, progressive non-fluent aphasia, n=12; amnestic Alzheimer’s disease, n=10 and a cohort of 26 healthy age-matched individuals. Approaching sounds were rated as more salient than withdrawing sounds by healthy older individuals but this behavioural response to salience did not differentiate healthy individuals from patients with dementia syndromes. Pupil responses to approaching sounds were greater than responses to withdrawing sounds in healthy older individuals and in patients with semantic dementia: this differential pupil response was reduced in patients with progressive nonfluent aphasia and Alzheimer’s disease relative both to the healthy control and semantic dementia groups, and did not correlate with nonverbal auditory semantic function. Autonomic responses to auditory salience are differentially affected by dementias and may constitute a novel biomarker of these diseases.

  11. Dementias show differential physiological responses to salient sounds

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    Fletcher, Phillip D.; Nicholas, Jennifer M.; Shakespeare, Timothy J.; Downey, Laura E.; Golden, Hannah L.; Agustus, Jennifer L.; Clark, Camilla N.; Mummery, Catherine J.; Schott, Jonathan M.; Crutch, Sebastian J.; Warren, Jason D.

    2015-01-01

    Abnormal responsiveness to salient sensory signals is often a prominent feature of dementia diseases, particularly the frontotemporal lobar degenerations, but has been little studied. Here we assessed processing of one important class of salient signals, looming sounds, in canonical dementia syndromes. We manipulated tones using intensity cues to create percepts of salient approaching (“looming”) or less salient withdrawing sounds. Pupil dilatation responses and behavioral rating responses to these stimuli were compared in patients fulfilling consensus criteria for dementia syndromes (semantic dementia, n = 10; behavioral variant frontotemporal dementia, n = 16, progressive nonfluent aphasia, n = 12; amnestic Alzheimer's disease, n = 10) and a cohort of 26 healthy age-matched individuals. Approaching sounds were rated as more salient than withdrawing sounds by healthy older individuals but this behavioral response to salience did not differentiate healthy individuals from patients with dementia syndromes. Pupil responses to approaching sounds were greater than responses to withdrawing sounds in healthy older individuals and in patients with semantic dementia: this differential pupil response was reduced in patients with progressive nonfluent aphasia and Alzheimer's disease relative both to the healthy control and semantic dementia groups, and did not correlate with nonverbal auditory semantic function. Autonomic responses to auditory salience are differentially affected by dementias and may constitute a novel biomarker of these diseases. PMID:25859194

  12. Lost for words or loss of memories? Autobiographical memory in semantic dementia.

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    Moss, H E; Kopelman, M D; Cappelletti, M; Davies, P de Mornay; Jaldow, E

    2003-12-01

    Recent reports have suggested that patients with semantic dementia show a loss of early (remote) auto-biographical memories with pronounced sparing of recent memories (Graham & Hodges, 1997; Snowden, Griffiths, & Neary, 1996), i.e., a 'reversed' temporal gradient or 'Ribot effect'. At first sight, these findings suggest that the deficits in 'semantic' dementia go beyond the semantic domain, involving aspects of autobiographical (episodic) memory. It has also been proposed that there is a 'step-like' function with personal memories preserved for 18 months to 2 years in the immediate past. This view is consistent with the theory that the hippocampal complex/medial temporal lobe (relatively intact in semantic dementia) plays a time-limited role in the acquisition and storage of memories, while the temporal neocortex (damaged in semantic dementia) is required for long-term storage and retrieval. In this study we ask whether (a) previous tests have underestimated the integrity of remote memory in semantic dementia as a result of not allowing for these patients' comprehension and language production difficulties, and (b) whether a recency effect, if obtained, is genuinely step-like or more graded. We used a cued autobiographical memory interview with semantic dementia patient, IH, to examine the effect of providing increasingly specific lexical cues to probe salient events throughout his lifespan. Results demonstrated that the provision of specific cues enabled IH to access and express memories from his childhood and early adulthood as well as from more recent times. There was a gentle recency effect only for intermediate levels of cueing, indicating that recent memories were easier to retrieve and/or express in the absence of specific cues, but this effect was graded, with no evidence of a step-like cut-off at 18 months or 2 years before testing. In brief, our findings are consistent with the view that the deficits in semantic dementia are predominantly or exclusively

  13. Simulating episodic memory deficits in semantic dementia with the TraceLink model

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    Meeter, M.; Murre, J.M.J.

    2004-01-01

    Although semantic dementia is primarily characterised by deficits in semantic memory, episodic memory is also impaired. Patients show poor recall of old autobiographical and semantic memories, with better retrieval of recent experiences; they can form new memories, and normal performance on

  14. “Pre-semantic” cognition revisited: Critical differences between semantic aphasia and semantic dementia

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    Jefferies, Elizabeth; Rogers, Timothy T.; Hopper, Samantha; Lambon Ralph, Matthew A.

    2010-01-01

    Patients with semantic dementia show a specific pattern of impairment on both verbal and non-verbal "pre-semantic" tasks, e.g., reading aloud, past tense generation, spelling to dictation, lexical decision, object decision, colour decision and delayed picture copying. All seven tasks are characterised by poorer performance for items that are atypical of the domain and "regularisation errors" (irregular/atypical items are produced as if they were domain-typical). The emergence of this pattern ...

  15. Distinct neural substrates of affective and cognitive theory of mind impairment in semantic dementia.

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    Bejanin, Alexandre; Chételat, Gaël; Laisney, Mickael; Pélerin, Alice; Landeau, Brigitte; Merck, Catherine; Belliard, Serge; de La Sayette, Vincent; Eustache, Francis; Desgranges, Béatrice

    2017-06-01

    Using structural MRI, we investigated the brain substrates of both affective and cognitive theory of mind (ToM) in 19 patients with semantic dementia. We also ran intrinsic connectivity analyses to identify the networks to which the substrates belong and whether they are functionally disturbed in semantic dementia. In line with previous studies, we observed a ToM impairment in patients with semantic dementia even when semantic memory was regressed out. Our results also highlighted different neural bases according to the nature (affective or cognitive) of the representations being inferred. The affective ToM deficit was associated with atrophy in the amygdala, suggesting the involvement of emotion-processing deficits in this impairment. By contrast, cognitive ToM performances were correlated with the volume of medial prefrontal and parietal regions, as well as the right frontal operculum. Intrinsic connectivity analyses revealed decreased functional connectivity, mainly between midline cortical regions and temporal regions. They also showed that left medial temporal regions were functionally isolated, a further possible hindrance to normal social cognitive functioning in semantic dementia. Overall, this study addressed for the first time the neuroanatomical substrates of both cognitive and affective ToM disruption in semantic dementia, highlighting disturbed connectivity within the networks that sustain these abilities.

  16. Right anterior temporal lobe dysfunction underlies theory of mind impairments in semantic dementia.

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    Irish, Muireann; Hodges, John R; Piguet, Olivier

    2014-04-01

    Semantic dementia is a progressive neurodegenerative disorder characterized by the amodal and profound loss of semantic knowledge attributable to the degeneration of the left anterior temporal lobe. Although traditionally conceptualized as a language disorder, patients with semantic dementia display significant alterations in behaviour and socioemotional functioning. Recent evidence points to an impaired capacity for theory of mind in predominantly left-lateralized cases of semantic dementia; however, it remains unclear to what extent semantic impairments contribute to these deficits. Further the neuroanatomical signature of such disturbance remains unknown. Here, we sought to determine the neural correlates of theory of mind performance in patients with left predominant semantic dementia (n=11), in contrast with disease-matched cases with behavioural-variant frontotemporal dementia (n=10) and Alzheimer's disease (n=10), and healthy older individuals (n=14) as control participants. Participants completed a simple cartoons task, in which they were required to describe physical and theory of mind scenarios. Irrespective of subscale, patients with semantic dementia exhibited marked impairments relative to control subjects; however, only theory of mind deficits persisted when we covaried for semantic comprehension. Voxel-based morphometry analyses revealed that atrophy in right anterior temporal lobe structures, including the right temporal fusiform cortex, right inferior temporal gyrus, bilateral temporal poles and amygdalae, correlated significantly with theory of mind impairments in the semantic dementia group. Our results point to the marked disruption of cognitive functions beyond the language domain in semantic dementia, not exclusively attributable to semantic processing impairments. The significant involvement of right anterior temporal structures suggests that with disease evolution, the encroachment of pathology into the contralateral hemisphere heralds the

  17. Phonological learning in semantic dementia.

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    Jefferies, Elizabeth; Bott, Samantha; Ehsan, Sheeba; Lambon Ralph, Matthew A

    2011-04-01

    Patients with semantic dementia (SD) have anterior temporal lobe (ATL) atrophy that gives rise to a highly selective deterioration of semantic knowledge. Despite pronounced anomia and poor comprehension of words and pictures, SD patients have well-formed, fluent speech and normal digit span. Given the intimate connection between phonological STM and word learning revealed by both neuropsychological and developmental studies, SD patients might be expected to show good acquisition of new phonological forms, even though their ability to map these onto meanings is impaired. In contradiction of these predictions, a limited amount of previous research has found poor learning of new phonological forms in SD. In a series of experiments, we examined whether SD patient, GE, could learn novel phonological sequences and, if so, under which circumstances. GE showed normal benefits of phonological knowledge in STM (i.e., normal phonotactic frequency and phonological similarity effects) but reduced support from semantic memory (i.e., poor immediate serial recall for semantically degraded words, characterised by frequent item errors). Next, we demonstrated normal learning of serial order information for repeated lists of single-digit number words using the Hebb paradigm: these items were well-understood allowing them to be repeated without frequent item errors. In contrast, patient GE showed little learning of nonsense syllable sequences using the same Hebb paradigm. Detailed analysis revealed that both GE and the controls showed a tendency to learn their own errors as opposed to the target items. Finally, we showed normal learning of phonological sequences for GE when he was prevented from repeating his errors. These findings confirm that the ATL atrophy in SD disrupts phonological processing for semantically degraded words but leaves the phonological architecture intact. Consequently, when item errors are minimised, phonological STM can support the acquisition of new phoneme

  18. Semantic amnesia without dementia: documentation of a case.

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    Rusconi, M L; Zago, S; Basso, A

    1997-06-01

    We described the case of a patient affected by a progressive semantic memory disorder associated with prevalent temporal lobe atrophy. This deficit seems to be "pure" in the sense that it has not been found to overlap with other cognitive deficits (intellectual, linguistic, perceptual, visuo-spatial etc.) for a long time. Furthermore, despite his impaired semantic knowledge, the autobiographical memory of the patient was largely intact. This case therefore represents a form of "semantic amnesia" without dementia, and supports the hypothesis that there is a partial distinction between "semantic" and "episodic" memory.

  19. Lexical-semantic knowledge about food in patients with different types of dementia

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    Raffaella Ida Rumiati

    2014-04-01

    Full Text Available While many theories agree that the conceptual knowledge is organized in categories, there is less agreement on the underlying organizational principle (e.g. Warrington & Shallice, 1984, Caramazza & Shelton, 1998; Capitani et al., 2003. Previous neuropsychological studies on semantic categories failed to clearly characterize the status of food as a category as they did not carefully distinguish between natural food and transformed food. Exploring how natural food and transformed food items are processed in patients suffering from primary dementia can allow us to test the theories of how semantic knowledge is organized in the brain. Thirty patients and 15 healthy controls matched for age and education took part in the study . Thirteen patients received a presumptive diagnosis of fronto-temporal dementia (FTD, 3 patients of Semantic Dementia (SD, and 14 of Alzheimer Dementia (AD. All participants performed 3 tasks tapping lexical-semantic knowledge about food and non-food items: confrontation naming (Task 1, categorization (Task 2, and word-to-picture matching (Task 3. Moreover, half food items were natural (e.g., apple and half transformed (e.g. grana cheese, while non-food items were half non edible natural items (e.g., plant and half kitchen implements. The results showed that, overall, patients performed poorer than controls on Tasks 1 and 3, with FTD-SD patients being more impaired than AD patients. When we compared performance on food versus non-food items, we observed that patients performed better on naming food than non-food items (Task 1. Specifically, FTD-SD patients displayed a significant difference between food and non-food items, while AD patients showed no difference. On Task 3 the same pattern was obtained. In addition, we observed that, across tasks, transformed food was processed better than natural food. These findings suggest that lexical-semantic processes are more prone to degradation in patients FTD-SD than in AD patients

  20. “The Mind Is Its Own Place”: Amelioration of Claustrophobia in Semantic Dementia

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    Camilla N. Clark

    2014-01-01

    Full Text Available Phobias are among the few intensely fearful experiences we regularly have in our everyday lives, yet the brain basis of phobic responses remains incompletely understood. Here we describe the case of a 71-year-old patient with a typical clinicoanatomical syndrome of semantic dementia led by selective (predominantly right-sided temporal lobe atrophy, who showed striking amelioration of previously disabling claustrophobia following onset of her cognitive syndrome. We interpret our patient’s newfound fearlessness as an interaction of damaged limbic and autonomic responsivity with loss of the cognitive meaning of previously threatening situations. This case has implications for our understanding of brain network disintegration in semantic dementia and the neurocognitive basis of phobias more generally.

  1. Autobiographical Memory in Semantic Dementia: A Longitudinal fMRI Study

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    Maguire, Eleanor A.; Kumaran, Dharshan; Hassabis, Demis; Kopelman, Michael D.

    2010-01-01

    Whilst patients with semantic dementia (SD) are known to suffer from semantic memory and language impairments, there is less agreement about whether memory for personal everyday experiences, autobiographical memory, is compromised. In healthy individuals, functional MRI (fMRI) has helped to delineate a consistent and distributed brain network…

  2. Comprehension of concrete and abstract words in semantic dementia

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    Jefferies, Elizabeth; Patterson, Karalyn; Jones, Roy W.; Lambon Ralph, Matthew A.

    2009-01-01

    The vast majority of brain-injured patients with semantic impairment have better comprehension of concrete than abstract words. In contrast, several patients with semantic dementia (SD), who show circumscribed atrophy of the anterior temporal lobes bilaterally, have been reported to show reverse imageability effects, i.e., relative preservation of abstract knowledge. Although these reports largely concern individual patients, some researchers have recently proposed that superior comprehension of abstract concepts is a characteristic feature of SD. This would imply that the anterior temporal lobes are particularly crucial for processing sensory aspects of semantic knowledge, which are associated with concrete not abstract concepts. However, functional neuroimaging studies of healthy participants do not unequivocally predict reverse imageability effects in SD because the temporal poles sometimes show greater activation for more abstract concepts. We examined a case-series of eleven SD patients on a synonym judgement test that orthogonally varied the frequency and imageability of the items. All patients had higher success rates for more imageable as well as more frequent words, suggesting that (a) the anterior temporal lobes underpin semantic knowledge for both concrete and abstract concepts, (b) more imageable items – perhaps due to their richer multimodal representations – are typically more robust in the face of global semantic degradation and (c) reverse imageability effects are not a characteristic feature of SD. PMID:19586212

  3. Wernicke's Aphasia Reflects a Combination of Acoustic-Phonological and Semantic Control Deficits: A Case-Series Comparison of Wernicke's Aphasia, Semantic Dementia and Semantic Aphasia

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    Robson, Holly; Sage, Karen; Lambon Ralph, Matthew A.

    2012-01-01

    Wernicke's aphasia (WA) is the classical neurological model of comprehension impairment and, as a result, the posterior temporal lobe is assumed to be critical to semantic cognition. This conclusion is potentially confused by (a) the existence of patient groups with semantic impairment following damage to other brain regions (semantic dementia and…

  4. The Role of Executive Function in the Semantic Comprehension Deficits of Stroke Aphasia and Semantic Dementia

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    Curtiss Chapman

    2015-05-01

    Results from 5 SD patients and 4 SA patients in our ongoing study suggest similar patterns of impairment on both semantic and executive function tasks for both patient groups. Both showed multi-modal semantic deficits via poor performance on at least 3 out of 5 semantic tasks tapping different modalities. Also, SA and SD patients showed no difference in consistency across semantic tasks (see Fig. 1a & b. Both groups also showed consistently poor performance on trail-making and verbal Stroop tasks compared to controls (see Figs. 1c & 1d. SD patients seem to be less impaired on both span measures (word span range: 2.17 – 4.43; digit span: 3.17 – 5.5 than SA patients (word span range: 1.63 – 3.75; digit span: 1.17 – 4.17, and performance was variable for both groups on non-verbal Stroop and picture-word interference. SD patients found many executive tasks too difficult to understand, which may be the reason for limited prior data for them on EF tasks.. These findings suggest that the use of syndrome categories like semantic dementia and comprehension-impaired stroke aphasia are not useful in distinguishing between storage and access deficits. Patients classified as having SD seem as likely as SA patients to have certain kinds of executive deficits and SA patients may be as likely as SD patients to show consistency across semantic tasks. The results imply that some other behavioral or neuroanatomical basis rather than syndrome classification should be used to address the hypothesized separation of storage vs. control aspects of semantic memory.

  5. Differentiation of semantic dementia and Alzheimer's disease using the Addenbrooke's Cognitive Examination (ACE).

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    Davies, R Rhys; Dawson, Kate; Mioshi, Eneida; Erzinçlioğlu, Sharon; Hodges, John R

    2008-04-01

    The Addenbrooke's Cognitive Examination (ACE) is a simple diagnostic tool bridging the gap between the very brief Mini Mental State Exam (MMSE) and much longer test batteries used by neuropsychologists which has proven extremely popular internationally. We aimed to assess the ability of the ACE to differentiate semantic dementia (SD) from Alzheimer's disease (AD). The ACE was administered to three groups: SD patients (n = 40) and two separate groups of AD patients (n = 40 in each), matched for overall ACE or MMSE score. Significant differences were found between SD and both AD groups for the ACE sub-scores of naming, reading and orientation in time. Discriminant analysis (SD versus AD) led to the formulation of a 'semantic index' (naming plus reading minus scores for serial-7s, orientation in time and drawing). Application of the semantic index to the patient data found values of less than zero to be predictive of SD rather than AD with 88% sensitivity and 90% specificity. Validation analysis in an independent sample of 24 SD and AD patients proved even more favourable. The overall ACE score is known to be a sensitive, and specific, indicator of early neurodegenerative dementia; this study shows that the ACE can also be used to detect SD through application of the semantic index.

  6. The Impact of Semantic Impairment on Verbal Short-Term Memory in Stroke Aphasia and Semantic Dementia: A Comparative Study

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    Jefferies, Elizabeth; Hoffman, Paul; Jones, Roy; Lambon Ralph, Matthew A.

    2008-01-01

    This study presents the first direct comparison of immediate serial recall in semantic dementia (SD) and transcortical sensory aphasia (TSA). Previous studies of the effect of semantic impairment on verbal short-term memory (STM) have led to important theoretical advances. However, different conclusions have been drawn from these two groups. This…

  7. Verbal and non-verbal semantic impairment: From fluent primary progressive aphasia to semantic dementia

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    Mirna Lie Hosogi Senaha

    Full Text Available Abstract Selective disturbances of semantic memory have attracted the interest of many investigators and the question of the existence of single or multiple semantic systems remains a very controversial theme in the literature. Objectives: To discuss the question of multiple semantic systems based on a longitudinal study of a patient who presented semantic dementia from fluent primary progressive aphasia. Methods: A 66 year-old woman with selective impairment of semantic memory was examined on two occasions, undergoing neuropsychological and language evaluations, the results of which were compared to those of three paired control individuals. Results: In the first evaluation, physical examination was normal and the score on the Mini-Mental State Examination was 26. Language evaluation revealed fluent speech, anomia, disturbance in word comprehension, preservation of the syntactic and phonological aspects of the language, besides surface dyslexia and dysgraphia. Autobiographical and episodic memories were relatively preserved. In semantic memory tests, the following dissociation was found: disturbance of verbal semantic memory with preservation of non-verbal semantic memory. Magnetic resonance of the brain revealed marked atrophy of the left anterior temporal lobe. After 14 months, the difficulties in verbal semantic memory had become more severe and the semantic disturbance, limited initially to the linguistic sphere, had worsened to involve non-verbal domains. Conclusions: Given the dissociation found in the first examination, we believe there is sufficient clinical evidence to refute the existence of a unitary semantic system.

  8. Semantic word category processing in semantic dementia and posterior cortical atrophy.

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    Shebani, Zubaida; Patterson, Karalyn; Nestor, Peter J; Diaz-de-Grenu, Lara Z; Dawson, Kate; Pulvermüller, Friedemann

    2017-08-01

    There is general agreement that perisylvian language cortex plays a major role in lexical and semantic processing; but the contribution of additional, more widespread, brain areas in the processing of different semantic word categories remains controversial. We investigated word processing in two groups of patients whose neurodegenerative diseases preferentially affect specific parts of the brain, to determine whether their performance would vary as a function of semantic categories proposed to recruit those brain regions. Cohorts with (i) Semantic Dementia (SD), who have anterior temporal-lobe atrophy, and (ii) Posterior Cortical Atrophy (PCA), who have predominantly parieto-occipital atrophy, performed a lexical decision test on words from five different lexico-semantic categories: colour (e.g., yellow), form (oval), number (seven), spatial prepositions (under) and function words (also). Sets of pseudo-word foils matched the target words in length and bi-/tri-gram frequency. Word-frequency was matched between the two visual word categories (colour and form) and across the three other categories (number, prepositions, and function words). Age-matched healthy individuals served as controls. Although broad word processing deficits were apparent in both patient groups, the deficit was strongest for colour words in SD and for spatial prepositions in PCA. The patterns of performance on the lexical decision task demonstrate (a) general lexicosemantic processing deficits in both groups, though more prominent in SD than in PCA, and (b) differential involvement of anterior-temporal and posterior-parietal cortex in the processing of specific semantic categories of words. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Paced Reading in Semantic Dementia: Word Knowledge Contributes to Phoneme Binding in Rapid Speech Production

    Science.gov (United States)

    Jefferies, Elizabeth; Grogan, John; Mapelli, Cristina; Isella, Valeria

    2012-01-01

    Patients with semantic dementia (SD) show deficits in phoneme binding in immediate serial recall: when attempting to reproduce a sequence of words that they no longer fully understand, they show frequent migrations of phonemes between items (e.g., cap, frog recalled as "frap, cog"). This suggests that verbal short-term memory emerges directly from…

  10. Semantic Dementia and Persisting Wernicke's Aphasia: Linguistic and Anatomical Profiles

    Science.gov (United States)

    Ogar, J. M.; Baldo, J. V.; Wilson, S. M.; Brambati, S. M.; Miller, B. L.; Dronkers, N. F.; Gorno-Tempini, M. L.

    2011-01-01

    Few studies have directly compared the clinical and anatomical characteristics of patients with progressive aphasia to those of patients with aphasia caused by stroke. In the current study we examined fluent forms of aphasia in these two groups, specifically semantic dementia (SD) and persisting Wernicke's aphasia (WA) due to stroke. We compared…

  11. A computational linguistic measure of clustering behavior on semantic verbal fluency task predicts risk of future dementia in the nun study.

    Science.gov (United States)

    Pakhomov, Serguei V S; Hemmy, Laura S

    2014-06-01

    Generative semantic verbal fluency (SVF) tests show early and disproportionate decline relative to other abilities in individuals developing Alzheimer's disease. Optimal performance on SVF tests depends on the efficiency of using clustered organization of semantically related items and the ability to switch between clusters. Traditional approaches to clustering and switching have relied on manual determination of clusters. We evaluated a novel automated computational linguistic approach for quantifying clustering behavior. Our approach is based on Latent Semantic Analysis (LSA) for computing strength of semantic relatedness between pairs of words produced in response to SVF test. The mean size of semantic clusters (MCS) and semantic chains (MChS) are calculated based on pairwise relatedness values between words. We evaluated the predictive validity of these measures on a set of 239 participants in the Nun Study, a longitudinal study of aging. All were cognitively intact at baseline assessment, measured with the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery, and were followed in 18-month waves for up to 20 years. The onset of either dementia or memory impairment were used as outcomes in Cox proportional hazards models adjusted for age and education and censored at follow-up waves 5 (6.3 years) and 13 (16.96 years). Higher MCS was associated with 38% reduction in dementia risk at wave 5 and 26% reduction at wave 13, but not with the onset of memory impairment. Higher [+1 standard deviation (SD)] MChS was associated with 39% dementia risk reduction at wave 5 but not wave 13, and association with memory impairment was not significant. Higher traditional SVF scores were associated with 22-29% memory impairment and 35-40% dementia risk reduction. SVF scores were not correlated with either MCS or MChS. Our study suggests that an automated approach to measuring clustering behavior can be used to estimate dementia risk in cognitively normal

  12. One Size Does Not Fit All: Face Emotion Processing Impairments in Semantic Dementia, Behavioural-Variant Frontotemporal Dementia and Alzheimer?s Disease Are Mediated by Distinct Cognitive Deficits

    OpenAIRE

    Miller, Laurie A.; Hsieh, Sharpley; Lah, Suncica; Savage, Sharon; Hodges, John R.; Piguet, Olivier

    2011-01-01

    Patients with frontotemporal dementia (both behavioural variant [bvFTD] and semantic dementia [SD]) as well as those with Alzheimer's disease (AD) show deficits on tests of face emotion processing, yet the mechanisms underlying these deficits have rarely been explored. We compared groups of patients with bvFTD (n = 17), SD (n = 12) or AD (n = 20) to an age- and education-matched group of healthy control subjects (n = 36) on three face emotion processing tasks (Ekman 60, Emotion Matching and E...

  13. A SEMantic and EPisodic Memory Test (SEMEP) Developed within the Embodied Cognition Framework: Application to Normal Aging, Alzheimer's Disease and Semantic Dementia.

    Science.gov (United States)

    Vallet, Guillaume T; Hudon, Carol; Bier, Nathalie; Macoir, Joël; Versace, Rémy; Simard, Martine

    2017-01-01

    Embodiment has highlighted the importance of sensory-motor components in cognition. Perception and memory are thus very tightly bound together, and episodic and semantic memories should rely on the same grounded memory traces. Reduced perception should then directly reduce the ability to encode and retrieve an episodic memory, as in normal aging. Multimodal integration deficits, as in Alzheimer's disease, should lead to more severe episodic memory impairment. The present study introduces a new memory test developed to take into account these assumptions. The SEMEP (SEMantic-Episodic) memory test proposes to assess conjointly semantic and episodic knowledge across multiple tasks: semantic matching, naming, free recall, and recognition. The performance of young adults is compared to healthy elderly adults (HE), patients with Alzheimer's disease (AD), and patients with semantic dementia (SD). The results show specific patterns of performance between the groups. HE commit memory errors only for presented but not to be remembered items. AD patients present the worst episodic memory performance associated with intrusion errors (recall or recognition of items never presented). They were the only group to not benefit from a visual isolation (addition of a yellow background), a method known to increase the distinctiveness of the memory traces. Finally, SD patients suffer from the most severe semantic impairment. To conclude, confusion errors are common across all the elderly groups, whereas AD was the only group to exhibit regular intrusion errors and SD patients to show severe semantic impairment.

  14. A SEMantic and EPisodic Memory Test (SEMEP Developed within the Embodied Cognition Framework: Application to Normal Aging, Alzheimer's Disease and Semantic Dementia

    Directory of Open Access Journals (Sweden)

    Guillaume T. Vallet

    2017-09-01

    Full Text Available Embodiment has highlighted the importance of sensory-motor components in cognition. Perception and memory are thus very tightly bound together, and episodic and semantic memories should rely on the same grounded memory traces. Reduced perception should then directly reduce the ability to encode and retrieve an episodic memory, as in normal aging. Multimodal integration deficits, as in Alzheimer's disease, should lead to more severe episodic memory impairment. The present study introduces a new memory test developed to take into account these assumptions. The SEMEP (SEMantic-Episodic memory test proposes to assess conjointly semantic and episodic knowledge across multiple tasks: semantic matching, naming, free recall, and recognition. The performance of young adults is compared to healthy elderly adults (HE, patients with Alzheimer's disease (AD, and patients with semantic dementia (SD. The results show specific patterns of performance between the groups. HE commit memory errors only for presented but not to be remembered items. AD patients present the worst episodic memory performance associated with intrusion errors (recall or recognition of items never presented. They were the only group to not benefit from a visual isolation (addition of a yellow background, a method known to increase the distinctiveness of the memory traces. Finally, SD patients suffer from the most severe semantic impairment. To conclude, confusion errors are common across all the elderly groups, whereas AD was the only group to exhibit regular intrusion errors and SD patients to show severe semantic impairment.

  15. The association between semantic dementia and surface dyslexia in Japanese.

    Science.gov (United States)

    Fushimi, Takao; Komori, Kenjiro; Ikeda, Manabu; Lambon Ralph, Matthew A; Patterson, Karalyn

    2009-03-01

    One theory about reading suggests that producing the correct pronunciations of written words, particularly less familiar words with an atypical spelling-sound relationship, relies in part on knowledge of the word's meaning. This hypothesis has been supported by reports of surface dyslexia in large case-series studies of English-speaking/reading patients with semantic dementia (SD), but would have increased credibility if it applied to other languages and writing systems as well. The hypothesis predicts that, of the two systems used to write Japanese, SD patients should be unimpaired at oral reading of kana because of its invariant relationship between orthography and phonology. By contrast, oral reading of kanji should be impaired in a graded fashion depending on the consistency characteristics of the kanji target words, with worst performance on words whose component characters take 'minority' (atypical) pronunciations, especially if the words are of lower frequency. Errors in kanji reading should primarily reflect assignment of more typical readings to the component characters in these atypical words. In the largest-ever-reported case series of Japanese patients with semantic dementia, we tested and confirmed this hypothesis.

  16. 'The quicksand of forgetfulness': semantic dementia in One hundred years of solitude.

    Science.gov (United States)

    Rascovsky, Katya; Growdon, Matthew E; Pardo, Isela R; Grossman, Scott; Miller, Bruce L

    2009-09-01

    This multidisciplinary article compares the pattern of memory loss described in Gabriel García Márquez's One Hundred Years of Solitude to that exhibited by patients with semantic dementia (SD). In his renowned novel, García Márquez depicts the plight of Macondo, a town struck by the dreaded insomnia plague. The most devastating symptom of the plague is not the impossibility of sleep, but rather the loss of 'the name and notion of things'. In an effort to combat this insidious loss of knowledge, the protagonist, José Arcadio Buendía, 'marked everything with its name: table, chair, clock, door, wall, bed, pan'. 'Studying the infinite possibilities of a loss of memory, he realized that the day might come when things would be recognized by their inscriptions but that no one would remember their use'. The cognitive impairments experienced by Macondo's inhabitants are remarkably similar to those observed in SD, a clinical syndrome characterized by a progressive breakdown of conceptual knowledge (semantic memory) in the context of relatively preserved day-to-day (episodic) memory. First recognized in 1975, it is now considered one of the main variants of frontotemporal lobar degeneration. Writing within the realm of magical realism and investigating the power of language as a form of communication, García Márquez provides beautiful descriptions of the loss of 'the name and notion of things' typical of the syndrome. He further speculates on ways to cope with this dissolution of meaning, ranging from 'the spell of an imaginary reality' to José Arcadio's 'memory machine', strategies that resonate with attempts by semantic dementia patients to cope with their disease. Remarkably, García Márquez created a striking literary depiction of collective semantic dementia before the syndrome was recognized in neurology. The novel also provides an inspiring and human account of one town's fight against 'the quicksand of forgetfulness'.

  17. Neural Substrates of Semantic Prospection – Evidence from the Dementias

    Science.gov (United States)

    Irish, Muireann; Eyre, Nadine; Dermody, Nadene; O’Callaghan, Claire; Hodges, John R.; Hornberger, Michael; Piguet, Olivier

    2016-01-01

    The ability to envisage personally relevant events at a future time point represents an incredibly sophisticated cognitive endeavor and one that appears to be intimately linked to episodic memory integrity. Far less is known regarding the neurocognitive mechanisms underpinning the capacity to envisage non-personal future occurrences, known as semantic future thinking. Moreover the degree of overlap between the neural substrates supporting episodic and semantic forms of prospection remains unclear. To this end, we sought to investigate the capacity for episodic and semantic future thinking in Alzheimer’s disease (n = 15) and disease-matched behavioral-variant frontotemporal dementia (n = 15), neurodegenerative disorders characterized by significant medial temporal lobe (MTL) and frontal pathology. Participants completed an assessment of past and future thinking across personal (episodic) and non-personal (semantic) domains, as part of a larger neuropsychological battery investigating episodic and semantic processing, and their performance was contrasted with 20 age- and education-matched healthy older Controls. Participants underwent whole-brain T1-weighted structural imaging and voxel-based morphometry analysis was conducted to determine the relationship between gray matter integrity and episodic and semantic future thinking. Relative to Controls, both patient groups displayed marked future thinking impairments, extending across episodic and semantic domains. Analyses of covariance revealed that while episodic future thinking deficits could be explained solely in terms of episodic memory proficiency, semantic prospection deficits reflected the interplay between episodic and semantic processing. Distinct neural correlates emerged for each form of future simulation with differential involvement of prefrontal, lateral temporal, and medial temporal regions. Notably, the hippocampus was implicated irrespective of future thinking domain, with the suggestion of

  18. Neural Substrates of Semantic Prospection – Evidence from the Dementias

    Directory of Open Access Journals (Sweden)

    Muireann eIrish

    2016-05-01

    Full Text Available The ability to envisage personally relevant events at a future time point represents an incredibly sophisticated cognitive endeavor and one that appears to be intimately linked to episodic memory integrity. Far less is known regarding the neurocognitive mechanisms underpinning the capacity to envisage non-personal future occurrences, known as semantic future thinking. Moreover the degree of overlap between the neural substrates supporting episodic and semantic forms of prospection remains unclear. To this end, we sought to investigate the capacity for episodic and semantic future thinking in Alzheimer’s disease (n = 15 and disease-matched behavioral-variant frontotemporal dementia (n = 15, neurodegenerative disorders characterized by significant medial temporal lobe and frontal pathology. Participants completed an assessment of past and future thinking across personal (episodic and non-personal (semantic domains, as part of a larger neuropsychological battery investigating episodic and semantic processing, and their performance was contrasted with 20 age- and education-matched healthy older Controls. Participants underwent whole-brain T1 weighted structural imaging and voxel-based morphometry analysis was conducted to determine the relationship between grey matter integrity and episodic and semantic future thinking. Relative to Controls, both patient groups displayed marked future thinking impairments, extending across episodic and semantic domains. Analyses of covariance revealed that while episodic future thinking deficits could be explained solely in terms of episodic memory proficiency, semantic prospection deficits reflected the interplay between episodic and semantic processing. Distinct neural correlates emerged for each form of future simulation with differential involvement of prefrontal, lateral temporal and medial temporal regions. Notably, the hippocampus was implicated irrespective of future thinking domain, with the suggestion of

  19. ‘The quicksand of forgetfulness’: semantic dementia in One Hundred Years of Solitude

    Science.gov (United States)

    Growdon, Matthew E.; Pardo, Isela R.; Grossman, Scott; Miller, Bruce L.

    2009-01-01

    This multidisciplinary article compares the pattern of memory loss described in Gabriel García Márquez's One Hundred Years of Solitude to that exhibited by patients with semantic dementia (SD). In his renowned novel, García Márquez depicts the plight of Macondo, a town struck by the dreaded insomnia plague. The most devastating symptom of the plague is not the impossibility of sleep, but rather the loss of ‘the name and notion of things’. In an effort to combat this insidious loss of knowledge, the protagonist, José Arcadio Buendía, ‘marked everything with its name: table, chair, clock, door, wall, bed, pan’. ‘Studying the infinite possibilities of a loss of memory, he realized that the day might come when things would be recognized by their inscriptions but that no one would remember their use’. The cognitive impairments experienced by Macondo's inhabitants are remarkably similar to those observed in SD, a clinical syndrome characterized by a progressive breakdown of conceptual knowledge (semantic memory) in the context of relatively preserved day-to-day (episodic) memory. First recognized in 1975, it is now considered one of the main variants of frontotemporal lobar degeneration. Writing within the realm of magical realism and investigating the power of language as a form of communication, García Márquez provides beautiful descriptions of the loss of ‘the name and notion of things’ typical of the syndrome. He further speculates on ways to cope with this dissolution of meaning, ranging from ‘the spell of an imaginary reality’ to José Arcadio's ‘memory machine’, strategies that resonate with attempts by semantic dementia patients to cope with their disease. Remarkably, García Márquez created a striking literary depiction of collective semantic dementia before the syndrome was recognized in neurology. The novel also provides an inspiring and human account of one town's fight against ‘the quicksand of forgetfulness’. PMID

  20. Somatic Symptom Disorder in Semantic Dementia: The Role of Alexisomia.

    Science.gov (United States)

    Gan, Joanna J; Lin, Andrew; Samimi, Mersal S; Mendez, Mario F

    Semantic dementia (SD) is a neurodegenerative disorder characterized by loss of semantic knowledge. SD may be associated with somatic symptom disorder due to excessive preoccupation with unidentified somatic sensations. To evaluate the frequency of somatic symptom disorder among patients with SD in comparison to comparably demented patients with Alzheimer׳s disease. A retrospective cohort study was conducted using clinical data from a referral-based behavioral neurology program. Fifty-three patients with SD meeting criteria for imaging-supported semantic variant primary progressive aphasia (another term for SD) were compared with 125 patients with clinically probable Alzheimer disease. Logistic regression controlled for sex, age, disease duration, education, overall cognitive impairment, and depression. The prevalence of somatic symptom disorder was significantly higher among patients with SD (41.5%) compared to patients with Alzheimer disease (11.2%) (odds ratio = 6:1; p Cotard syndrome or the delusion that unidentified somatic symptoms signify death or deterioration. SD, a disorder of semantic knowledge, is associated with somatic symptom disorder from impaired identification of somatic sensations. Their inability to read and name somatic sensations, or "alexisomia," results in disproportionate and persistent concern about somatic sensations with consequent significant disability. Copyright © 2016 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

  1. Fluent Aphasia in Telugu: A Case Comparison Study of Semantic Dementia and Stroke Aphasia

    Science.gov (United States)

    Alladi, Suvarna; Mridula, Rukmini; Mekala, Shailaja; Rupela, Vani; Kaul, Subhash

    2010-01-01

    This study presents two cases with fluent aphasia in Telugu with semantic dementia and post-stroke fluent aphasia. Comparable scores were obtained on the conventional neuropsychological and language tests that were administered on the two cases. Both cases demonstrated fluent, grammatical and well-articulated speech with little content, impaired…

  2. Frontotemporal lobar degeneration with ubiquitin pathology: an autopsy case presenting with semantic dementia and upper motor neuron signs with a clinical course of 19 years.

    Science.gov (United States)

    Yokota, Osamu; Tsuchiya, Kuniaki; Itoh, Yoshinori; Ishizu, Hideki; Akiyama, Haruhiko; Ikeda, Manabu; Kuzuhara, Shigeki; Otomo, Eiichi

    2006-12-01

    We report a case of a right-handed 74-year-old man who showed semantic dementia with a disease duration of 19 years. He initially presented with excessive use of pronouns and semantic paraphasia at the age of 55 years. Impairment of object recognition developed 5 years after the onset. Face recognition impairment and stereotypic behaviors developed 11 years after onset, and pyramidal signs 2 years before death. Pathological examination disclosed circumscribed severe atrophy in not only the bilateral temporal tips but also in the left precentral gyrus and pars opercularis in a motor speech field. Pyramidal tract involvement and loss of Betz cells were also evident. On the other hand, neurons in the anterior horns and hypoglossal nuclei were spared in number, although astrocytes were mildly proliferated. Ubiquitin-positive lesions were observed in the hippocampus, and frontal and temporal cortices. Neither Bunina bodies nor Pick bodies were present. These features clinically fit the international diagnostic criteria of semantic dementia and, histopathologically, frontotemporal lobar degeneration with motor neuron disease (FTLD-MND). This case suggests that (1) the distribution of cortical lesions associated with language disturbance is not uniform in FTLD-MND. It may be that only some cases of FTLD with ubiquitin pathology develop semantic dementia despite the high incidence of language disturbance, and (2) the precentral gyrus can be severely affected in FTLD-MND. After reviewing previous cases of FTLD-MND with a clinical course of more than 10 years, we also noticed that (3) FTLD-MND cases with a long disease duration often show upper motor neuron-predominant involvement.

  3. Semantic Memory in the Clinical Progression of Alzheimer Disease.

    Science.gov (United States)

    Tchakoute, Christophe T; Sainani, Kristin L; Henderson, Victor W

    2017-09-01

    Semantic memory measures may be useful in tracking and predicting progression of Alzheimer disease. We investigated relationships among semantic memory tasks and their 1-year predictive value in women with Alzheimer disease. We conducted secondary analyses of a randomized clinical trial of raloxifene in 42 women with late-onset mild-to-moderate Alzheimer disease. We assessed semantic memory with tests of oral confrontation naming, category fluency, semantic recognition and semantic naming, and semantic density in written narrative discourse. We measured global cognition (Alzheimer Disease Assessment Scale, cognitive subscale), dementia severity (Clinical Dementia Rating sum of boxes), and daily function (Activities of Daily Living Inventory) at baseline and 1 year. At baseline and 1 year, most semantic memory scores correlated highly or moderately with each other and with global cognition, dementia severity, and daily function. Semantic memory task performance at 1 year had worsened one-third to one-half standard deviation. Factor analysis of baseline test scores distinguished processes in semantic and lexical retrieval (semantic recognition, semantic naming, confrontation naming) from processes in lexical search (semantic density, category fluency). The semantic-lexical retrieval factor predicted global cognition at 1 year. Considered separately, baseline confrontation naming and category fluency predicted dementia severity, while semantic recognition and a composite of semantic recognition and semantic naming predicted global cognition. No individual semantic memory test predicted daily function. Semantic-lexical retrieval and lexical search may represent distinct aspects of semantic memory. Semantic memory processes are sensitive to cognitive decline and dementia severity in Alzheimer disease.

  4. The word processing deficit in semantic dementia: all categories are equal, but some categories are more equal than others.

    Science.gov (United States)

    Pulvermüller, Friedemann; Cooper-Pye, Elisa; Dine, Clare; Hauk, Olaf; Nestor, Peter J; Patterson, Karalyn

    2010-09-01

    It has been claimed that semantic dementia (SD), the temporal variant of fronto-temporal dementia, is characterized by an across-the-board deficit affecting all types of conceptual knowledge. We here confirm this generalized deficit but also report differential degrees of impairment in processing specific semantic word categories in a case series of SD patients (N = 11). Within the domain of words with strong visually grounded meaning, the patients' lexical decision accuracy was more impaired for color-related than for form-related words. Likewise, within the domain of action verbs, the patients' performance was worse for words referring to face movements and speech acts than for words semantically linked to actions performed with the hand and arm. Psycholinguistic properties were matched between the stimulus groups entering these contrasts; an explanation for the differential degrees of impairment must therefore involve semantic features of the words in the different conditions. Furthermore, this specific pattern of deficits cannot be captured by classic category distinctions such as nouns versus verbs or living versus nonliving things. Evidence from previous neuroimaging research indicates that color- and face/speech-related words, respectively, draw most heavily on anterior-temporal and inferior-frontal areas, the structures most affected in SD. Our account combines (a) the notion of an anterior-temporal amodal semantic "hub" to explain the profound across-the-board deficit in SD word processing, with (b) a semantic topography model of category-specific circuits whose cortical distributions reflect semantic features of the words and concepts represented.

  5. Atrophy progression in semantic dementia with asymmetric temporal involvement: a tensor-based morphometry study.

    Science.gov (United States)

    Brambati, S M; Rankin, K P; Narvid, J; Seeley, W W; Dean, D; Rosen, H J; Miller, B L; Ashburner, J; Gorno-Tempini, M L

    2009-01-01

    We performed a longitudinal anatomical study to map the progression of gray matter atrophy in anatomically defined predominantly left (LTLV) and right (RTLV) temporal lobe variants of semantic dementia (SD). T1-weighted MRI scans were obtained at presentation and one-year follow-up from 13 LTLV, 6 RTLV, and 25 control subjects. Tensor-based morphometry (TBM) in SPM2 was applied to derive a voxel-wise estimation of regional tissue loss over time from the deformation field required to warp the follow-up scan to the presentation scan in each subject. When compared to controls, both LTLV and RTLV showed significant progression of gray matter atrophy not only within the temporal lobe most affected at presentation, but also in the controlateral temporal regions (p<0.05 FWE corrected). In LTLV, significant progression of volume loss also involved the ventromedial frontal and the left anterior insular regions. These results identified the anatomic substrates of the previously reported clinical evolution of LTLV and RTLV into a unique 'merged' clinical syndrome characterized by semantic and behavioral deficits and bilateral temporal atrophy.

  6. The left fusiform gyrus is a critical region contributing to the core behavioral profile of semantic dementia

    Directory of Open Access Journals (Sweden)

    Junhua eDing

    2016-05-01

    Full Text Available Given that extensive cerebral regions are co-atrophic in semantic dementia (SD, it is not yet known which critical regions (SD-semantic-critical regions are really responsible for the semantic deficits of SD. To identify the SD-semantic-critical regions, we explored the relationship between the degree of cerebral atrophy in the whole brain and the severity of semantic deficits in 19 individuals with SD. We found that the gray matter volumes of two regions [left fusiform gyrus (lFFG and left parahippocampal gyrus (lPHG] significantly correlated with the semantic scores of patients with SD. Importantly, the effects of the lFFG remained significant after controlling for the gray matter volumes of the lPHG. Moreover, the effects of the region could not be accounted for by the total gray matter volume, general cognitive ability, laterality of brain atrophy, or control task performance. We further observed that each atrophic portion of the lFFG along the anterior-posterior axis might dedicate to the loss of semantic functions in SD. These results reveal that the lFFG could be a critical region contributing to the semantic deficits of SD.

  7. Topological Alterations and Symptom-Relevant Modules in the Whole-Brain Structural Network in Semantic Dementia.

    Science.gov (United States)

    Ding, Junhua; Chen, Keliang; Zhang, Weibin; Li, Ming; Chen, Yan; Yang, Qing; Lv, Yingru; Guo, Qihao; Han, Zaizhu

    2017-01-01

    Semantic dementia (SD) is characterized by a selective decline in semantic processing. Although the neuropsychological pattern of this disease has been identified, its topological global alterations and symptom-relevant modules in the whole-brain anatomical network have not been fully elucidated. This study aims to explore the topological alteration of anatomical network in SD and reveal the modules associated with semantic deficits in this disease. We first constructed the whole-brain white-matter networks of 20 healthy controls and 19 patients with SD. Then, the network metrics of graph theory were compared between these two groups. Finally, we separated the network of SD patients into different modules and correlated the structural integrity of each module with the severity of the semantic deficits across patients. The network of the SD patients presented a significantly reduced global efficiency, indicating that the long-distance connections were damaged. The network was divided into the following four distinctive modules: the left temporal/occipital/parietal, frontal, right temporal/occipital, and frontal/parietal modules. The first two modules were associated with the semantic deficits of SD. These findings illustrate the skeleton of the neuroanatomical network of SD patients and highlight the key role of the left temporal/occipital/parietal module and the left frontal module in semantic processing.

  8. Beyond the temporal pole: limbic memory circuit in the semantic variant of primary progressive aphasia.

    Science.gov (United States)

    Tan, Rachel H; Wong, Stephanie; Kril, Jillian J; Piguet, Olivier; Hornberger, Michael; Hodges, John R; Halliday, Glenda M

    2014-07-01

    Despite accruing evidence for relative preservation of episodic memory in the semantic variant of primary progressive aphasia (previously semantic dementia), the neural basis for this remains unclear, particularly in light of their well-established hippocampal involvement. We recently investigated the Papez network of memory structures across pathological subtypes of behavioural variant frontotemporal dementia and demonstrated severe degeneration of all relay nodes, with the anterior thalamus in particular emerging as crucial for intact episodic memory. The present study investigated the status of key components of Papez circuit (hippocampus, mammillary bodies, anterior thalamus, cingulate cortex) and anterior temporal cortex using volumetric and quantitative cell counting methods in pathologically-confirmed cases with semantic variant of primary progressive aphasia (n = 8; 61-83 years; three males), behavioural variant frontotemporal dementia with TDP pathology (n = 9; 53-82 years; six males) and healthy controls (n = 8, 50-86 years; four males). Behavioural variant frontotemporal dementia cases with TDP pathology were selected because of the association between the semantic variant of primary progressive aphasia and TDP pathology. Our findings revealed that the semantic variant of primary progressive aphasia and behavioural variant frontotemporal dementia show similar degrees of anterior thalamic atrophy. The mammillary bodies and hippocampal body and tail were preserved in the semantic variant of primary progressive aphasia but were significantly atrophic in behavioural variant frontotemporal dementia. Importantly, atrophy in the anterior thalamus and mild progressive atrophy in the body of the hippocampus emerged as the main memory circuit regions correlated with increasing dementia severity in the semantic variant of primary progressive aphasia. Quantitation of neuronal populations in the cingulate cortices confirmed the selective loss of anterior cingulate

  9. Autobiographical Memory in Normal Ageing and Dementia

    Directory of Open Access Journals (Sweden)

    Harvey J. Sagar

    1991-01-01

    Full Text Available Autobiographical memories in young and elderly normal subjects are drawn mostly from the recent past but elderly subjects relate a second peak of memories from early adulthood. Memory for remote past public events is relatively preserved in dementia, possibly reflecting integrity of semantic relative to episodic memory. We examined recall of specific, consistent autobiographical episodes in Alzheimer's disease (AD in response to cue words. Patients and control subjects drew most memories from the recent 20 years: episode age related to anterograde memory function but not subject age or dementia. Subjects also related a secondary peak of memories from early adulthood; episode age related to subject age and severity of dementia. The results suggest that preferential recall of memories from early adulthood is based on the salience of retrieval cues, altered by age and dementia, superimposed on a temporal gradient of semantic memory. Further, AD shows behavioural similarity to normal ageing.

  10. Semantic Verbal Fluency test in dementia: Preliminary retrospective analysis

    Directory of Open Access Journals (Sweden)

    Marcos Lopes

    Full Text Available Abstract The Semantic Verbal Fluency (SVF test entails the generation of words from a given category within a pre-set time of 60 seconds. Objectives: To verify whether socio-demographic and clinical data of individuals with dementia correlate with the performance on the SVF test and to ascertain whether differences among the criteria of number of answers, clusters and data spread over the intervals, predict clinical results. Methods: This was a retrospective study of 49 charts of demented patients classified according to the Clinical Dementia Rating (CDR scale. We correlated education, age and gender, as well as CDR and Mini-Mental State Exam (MMSE scores with the number of answers, clustering and switching distributed over four 15-second intervals on the SVF test. Results: The correlation between number of answers and quartiles was weak (r=0.407, p=0.004; r=0.484, p<0.001 but correlation between the number of clusters and responses was strong (r=0.883, p<0.001. The number of items on the SVF was statistically significant with MMSE score (p=0.01 and there was a tendency for significance on the CDR (p=0.06. The results indicated little activity regarding what we propose to call cluster recalling in the two groups. Discussion: The SVF test, using number of items generated, was found to be more effective than classic screening tests in terms of speed and ease of application in patients with CDR 2 and 3.

  11. Auditory conflict and congruence in frontotemporal dementia.

    Science.gov (United States)

    Clark, Camilla N; Nicholas, Jennifer M; Agustus, Jennifer L; Hardy, Christopher J D; Russell, Lucy L; Brotherhood, Emilie V; Dick, Katrina M; Marshall, Charles R; Mummery, Catherine J; Rohrer, Jonathan D; Warren, Jason D

    2017-09-01

    Impaired analysis of signal conflict and congruence may contribute to diverse socio-emotional symptoms in frontotemporal dementias, however the underlying mechanisms have not been defined. Here we addressed this issue in patients with behavioural variant frontotemporal dementia (bvFTD; n = 19) and semantic dementia (SD; n = 10) relative to healthy older individuals (n = 20). We created auditory scenes in which semantic and emotional congruity of constituent sounds were independently probed; associated tasks controlled for auditory perceptual similarity, scene parsing and semantic competence. Neuroanatomical correlates of auditory congruity processing were assessed using voxel-based morphometry. Relative to healthy controls, both the bvFTD and SD groups had impaired semantic and emotional congruity processing (after taking auditory control task performance into account) and reduced affective integration of sounds into scenes. Grey matter correlates of auditory semantic congruity processing were identified in distributed regions encompassing prefrontal, parieto-temporal and insular areas and correlates of auditory emotional congruity in partly overlapping temporal, insular and striatal regions. Our findings suggest that decoding of auditory signal relatedness may probe a generic cognitive mechanism and neural architecture underpinning frontotemporal dementia syndromes. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  12. Frequency and Severity of Semantic Deficits in a Consecutive Memory Clinic Cohort

    DEFF Research Database (Denmark)

    Vogel, Asmus; Johannsen, Peter; Stokholm, Jette

    2014-01-01

    Background/Aim: Semantic memory deficits have been shown in dementia and mild cognitive impairment (MCI) by group comparisons. The aim of this study is to investigate the frequency of impairments on tests with semantic content in patients with dementia, MCI (amnestic and non-amnestic) and affective......). However, patients with affective disorders also had mild impairments on tests tapping semantic memory (25% were impaired on the most sensitive tests). Impairments on the Famous faces test were more frequently found in dementia and MCI as compared to patients with affective disorders. Conclusion: Short...... tests with semantic memory content are sensitive to changes in dementia and MCI, but impairments on such tests may also be found in other diseases, e.g. affective disorders. © 2014 S. Karger AG, Basel....

  13. Semantic memory in object use.

    Science.gov (United States)

    Silveri, Maria Caterina; Ciccarelli, Nicoletta

    2009-10-01

    We studied five patients with semantic memory disorders, four with semantic dementia and one with herpes simplex virus encephalitis, to investigate the involvement of semantic conceptual knowledge in object use. Comparisons between patients who had semantic deficits of different severity, as well as the follow-up, showed that the ability to use objects was largely preserved when the deficit was mild but progressively decayed as the deficit became more severe. Naming was generally more impaired than object use. Production tasks (pantomime execution and actual object use) and comprehension tasks (pantomime recognition and action recognition) as well as functional knowledge about objects were impaired when the semantic deficit was severe. Semantic and unrelated errors were produced during object use, but actions were always fluent and patients performed normally on a novel tools task in which the semantic demand was minimal. Patients with severe semantic deficits scored borderline on ideational apraxia tasks. Our data indicate that functional semantic knowledge is crucial for using objects in a conventional way and suggest that non-semantic factors, mainly non-declarative components of memory, might compensate to some extent for semantic disorders and guarantee some residual ability to use very common objects independently of semantic knowledge.

  14. The contribution of executive control to semantic cognition: Convergent evidence from semantic aphasia and executive dysfunction.

    Science.gov (United States)

    Thompson, Hannah E; Almaghyuli, Azizah; Noonan, Krist A; Barak, Ohr; Lambon Ralph, Matthew A; Jefferies, Elizabeth

    2018-01-03

    Semantic cognition, as described by the controlled semantic cognition (CSC) framework (Rogers et al., , Neuropsychologia, 76, 220), involves two key components: activation of coherent, generalizable concepts within a heteromodal 'hub' in combination with modality-specific features (spokes), and a constraining mechanism that manipulates and gates this knowledge to generate time- and task-appropriate behaviour. Executive-semantic goal representations, largely supported by executive regions such as frontal and parietal cortex, are thought to allow the generation of non-dominant aspects of knowledge when these are appropriate for the task or context. Semantic aphasia (SA) patients have executive-semantic deficits, and these are correlated with general executive impairment. If the CSC proposal is correct, patients with executive impairment should not only exhibit impaired semantic cognition, but should also show characteristics that align with those observed in SA. This possibility remains largely untested, as patients selected on the basis that they show executive impairment (i.e., with 'dysexecutive syndrome') have not been extensively tested on tasks tapping semantic control and have not been previously compared with SA cases. We explored conceptual processing in 12 patients showing symptoms consistent with dysexecutive syndrome (DYS) and 24 SA patients, using a range of multimodal semantic assessments which manipulated control demands. Patients with executive impairments, despite not being selected to show semantic impairments, nevertheless showed parallel patterns to SA cases. They showed strong effects of distractor strength, cues and miscues, and probe-target distance, plus minimal effects of word frequency on comprehension (unlike semantic dementia patients with degradation of conceptual knowledge). This supports a component process account of semantic cognition in which retrieval is shaped by control processes, and confirms that deficits in SA patients reflect

  15. Language and Dementia: Neuropsychological Aspects

    OpenAIRE

    Kempler, Daniel; Goral, Mira

    2008-01-01

    This article reviews recent evidence for the relationship between extralinguistic cognitive and language abilities in dementia. A survey of data from investigations of three dementia syndromes (Alzheimer's disease, semantic dementia and progressive nonfluent aphasia) reveals that, more often than not, deterioration of conceptual organization appears associated with lexical impairments, whereas impairments in executive function are associated with sentence- and discourse-level deficits. These ...

  16. Dissociation of explicit and implicit long-term memory consolidation in semantic dementia: a case study.

    Science.gov (United States)

    Tu, S; Mioshi, E; Savage, S; Hodges, J R; Hornberger, M

    2013-08-01

    We report a case study of a semantic dementia patient, whose episodic memory consolidation was tested over a 2-month period. The results reveal that despite early retention of information, the patient lost all explicit information of the newly learnt material after 2 weeks. By contrast, he retained implicit word information even after a 4-week delay. These findings highlight the critical time window of 2-4 weeks in which newly learnt information should be re-encoded in rehabilitations studies. The results also indicate that learnt information can be still accessed with implicit retrieval strategies when explicit retrieval fails.

  17. Mechanical problem-solving strategies in Alzheimer's disease and semantic dementia.

    Science.gov (United States)

    Lesourd, Mathieu; Baumard, Josselin; Jarry, Christophe; Etcharry-Bouyx, Frédérique; Belliard, Serge; Moreaud, Olivier; Croisile, Bernard; Chauviré, Valérie; Granjon, Marine; Le Gall, Didier; Osiurak, François

    2016-07-01

    The goal of this study was to explore whether the tool-use disorders observed in Alzheimer's disease (AD) and semantic dementia (SD) are of the same nature as those observed in left brain-damaged (LBD) patients. Recent evidence indicates that LBD patients with apraxia of tool use encounter difficulties in solving mechanical problems, characterized by the absence of specific strategies. This pattern may show the presence of impaired mechanical knowledge, critical for both familiar and novel tool use. So, we explored the strategies followed by AD and SD patients in mechanical problem-solving tasks in order to determine whether mechanical knowledge is also impaired in these patients. We used a mechanical problem-solving task in both choice (i.e., several tools were proposed) and no-choice (i.e., only 1 tool was proposed) conditions. We analyzed quantitative data and strategy profiles. AD patients but not SD patients met difficulties in solving mechanical problem-solving tasks. However, the key finding is that AD patients, despite their difficulties, showed strategy profiles that are similar to that of SD patients or controls. Moreover, AD patients exhibited a strategy profile distinct from the one previously observed in LBD patients. Those observations lead us to consider that difficulties met by AD patients to solve mechanical problems or even to use familiar tools may not be caused by mechanical knowledge impairment per se. In broad terms, what we call apraxia of tool use in AD is certainly not the same as apraxia of tool use observed in LBD patients. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  18. A tale of two hemispheres: Contrasting socioemotional dysfunction in right- versus left-lateralised semantic dementia

    Directory of Open Access Journals (Sweden)

    Muireann Irish

    Full Text Available ABSTRACT Objective: Semantic dementia, a subtype of frontotemporal lobar degeneration, is characterised by cross-modal loss of conceptual knowledge attributable to progressive degeneration of the left anterior temporal lobe. Much less is known regarding the clinical presentation of SD patients with predominantly right-lateralised atrophy. Recent reports emphasise marked socioemotional and behavioural disturbances in such cases. Given the importance of the right anterior temporal lobes in social cognition, we hypothesised that socioemotional functioning would be disproportionately affected in right versus left-lateralised SD cases. Methods: We assessed well-characterised cases of predominantly right (n=10 and left (n=12 SD and 20 matched healthy controls on tests of emotion processing and interpersonal functioning. Results: Right SD cases showed disproportionate difficulties in the recognition of positive and negative facial emotions, specifically happiness and anger, compared with left SD cases. Deficits in anger recognition persisted in right SD despite covarying for facial and semantic processing. On a contextually rich task of emotion recognition using multimodal videos, no subgroup differences were evident. Finally, empathic concern was rated as significantly lower by caregivers of right versus left SD cases. Overall, the extent of socioemotional disturbance was associated with the degree of behavioural changes in SD. Conclusion: Our results reveal considerable overlap in the extent to which socioemotional processes are disrupted in left and right-lateralised cases of SD. Notably, however, right SD cases show disproportionate deficits for recognition of facial emotions and the capacity for empathic concern, supporting a specialised role for the right anterior temporal lobes in mediating these cognitive functions.

  19. Varieties of semantic 'access' deficit in Wernicke's aphasia and semantic aphasia.

    Science.gov (United States)

    Thompson, Hannah E; Robson, Holly; Lambon Ralph, Matthew A; Jefferies, Elizabeth

    2015-12-01

    Comprehension deficits are common in stroke aphasia, including in cases with (i) semantic aphasia, characterized by poor executive control of semantic processing across verbal and non-verbal modalities; and (ii) Wernicke's aphasia, associated with poor auditory-verbal comprehension and repetition, plus fluent speech with jargon. However, the varieties of these comprehension problems, and their underlying causes, are not well understood. Both patient groups exhibit some type of semantic 'access' deficit, as opposed to the 'storage' deficits observed in semantic dementia. Nevertheless, existing descriptions suggest that these patients might have different varieties of 'access' impairment-related to difficulty resolving competition (in semantic aphasia) versus initial activation of concepts from sensory inputs (in Wernicke's aphasia). We used a case series design to compare patients with Wernicke's aphasia and those with semantic aphasia on Warrington's paradigmatic assessment of semantic 'access' deficits. In these verbal and non-verbal matching tasks, a small set of semantically-related items are repeatedly presented over several cycles so that the target on one trial becomes a distractor on another (building up interference and eliciting semantic 'blocking' effects). Patients with Wernicke's aphasia and semantic aphasia were distinguished according to lesion location in the temporal cortex, but in each group, some individuals had additional prefrontal damage. Both of these aspects of lesion variability-one that mapped onto classical 'syndromes' and one that did not-predicted aspects of the semantic 'access' deficit. Both semantic aphasia and Wernicke's aphasia cases showed multimodal semantic impairment, although as expected, the Wernicke's aphasia group showed greater deficits on auditory-verbal than picture judgements. Distribution of damage in the temporal lobe was crucial for predicting the initially 'beneficial' effects of stimulus repetition: cases with

  20. Contrasting patterns of comprehension for superordinate, basic-level, and subordinate names in semantic dementia and aphasic stroke patients.

    Science.gov (United States)

    Crutch, Sebastian J; Warrington, Elizabeth K

    2008-06-01

    It is well established that patients with semantic memory impairment show a relative sparing of general superordinate information as compared with more detailed item-specific information. The objective of the current study was to examine whether or not this superordinate superiority effect is also reliably observed in individuals with stroke. The participants were 3 patients with a diagnosis of semantic dementia (SD) and 4 left middle cerebral artery stroke patients. In the first experiment, participants were administered a series of spoken-word-picture matching tasks, in which picture identity was probed under two conditions: item name (e.g., goose, beetle, shark, hedgehog) and superordinate name (e.g., bird, insect, fish, mammal). The SD patients showed the predicted pattern of performance, identifying stimuli significantly more accurately by their superordinate term than by their specific name. By contrast, the stroke patients showed the reverse pattern of inferior performance in the superordinate condition in all versions of the experimental task. In a second experiment comparing comprehension ofbasic-level names (e.g., dog, bird, fish) and subordinate-level names (e.g., Dalmatian, sparrow, trout), stroke patients also showed a reversal of the normal basic-level effect, showing less accurate comprehension of basic-level names. The pattern of results documented among the stroke patients cannot be accommodated obviously or readily by existing models of conceptual knowledge. These contrasting abilities of SD patients, stroke patients, and normal healthy participants to process subordinate, basic-level, and superordinate names are considered in relation to disorders of executive processing and taxonomic categorization.

  1. The special status of verbal knowledge in semantic memory: evidence from performance of semantically impaired subjects on verbalizable and non-verbalizable versions of the object decision task.

    Science.gov (United States)

    Zannino, Gian Daniele; Perri, Roberta; Monaco, Marco; Caltagirone, Carlo; Luzzi, Simona; Carlesimo, Giovanni A

    2014-01-01

    According to the semantic hub hypothesis, a supramodal semantic hub is equally needed to deal with verbal and extraverbal "surface" representations. Damage to the supramodal hub is thought to underlie the crossmodal impairment observed in selective semantic deficits. In the present paper, we provide evidence supporting an alternative view: we hold that semantic impairment is not equal across domains but affects verbal behavior disproportionately. We investigated our hypothesis by manipulating the verbal load in an object decision task. Two pathological groups showing different levels of semantic impairment were enrolled together with their normal controls. The severe group included 10 subjects with semantic dementia and the mild group 10 subjects with Alzheimer's disease. In keeping with our hypothesis, when shifting from the low verbal load to the high verbal load condition, brain-damaged individuals, as compared to controls, showed a disproportionate impairment as a function of the severity of their semantic deficit. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Frontotemporal dementia: An updated overview

    OpenAIRE

    Mohandas, E.; Rajmohan, V.

    2009-01-01

    Frontotemporal dementia (FTD) is a progressive neurodegenerative syndrome occurring between 45 and 65 years. The syndrome is also called frontotemporal lobar degeneration (FTLD). However, FTLD refers to a larger group of disorders FTD being one of its subgroups. The other subgroups of FTLD are progressive nonfluent aphasia (PFNA), and semantic dementia (SD). FTLD is characterized by atrophy of prefrontal and anterior temporal cortices. FTD occurs in 5-15% of patients with dementia and it is t...

  3. Vocabulary relearning in semantic dementia: Positive and negative consequences of increasing variability in the learning experience.

    Science.gov (United States)

    Hoffman, Paul; Clarke, Natasha; Jones, Roy W; Noonan, Krist A

    2015-09-01

    Anomia therapy typically aims to improve patients' communication ability through targeted practice in naming a set of particular items. For such interventions to be of maximum benefit, the use of trained (or relearned) vocabulary must generalise from the therapy setting into novel situations. We investigated relearning in three patients with semantic dementia, a condition that has been associated with poor generalisation of relearned vocabulary. We tested two manipulations designed to improve generalisation of relearned words by introducing greater variation into the learning experience. In the first study, we found that trained items were retained more successfully when they were presented in a variety of different sequences during learning. In the second study, we found that training items using a range of different pictured exemplars improved the patients' ability to generalise words to novel instances of the same object. However, in one patient this came at the cost of inappropriate over-generalisations, in which trained words were incorrectly used to name semantically or visually similar objects. We propose that more variable learning experiences benefit patients because they shift responsibility for learning away from the inflexible hippocampal learning system and towards the semantic system. The success of this approach therefore depends critically on the integrity of the semantic representations of the items being trained. Patients with naming impairments in the context of relatively mild comprehension deficits are most likely to benefit from this approach, while avoiding the negative consequences of over-generalisation. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Varieties of semantic ‘access’ deficit in Wernicke’s aphasia and semantic aphasia

    Science.gov (United States)

    Robson, Holly; Lambon Ralph, Matthew A.; Jefferies, Elizabeth

    2015-01-01

    Comprehension deficits are common in stroke aphasia, including in cases with (i) semantic aphasia, characterized by poor executive control of semantic processing across verbal and non-verbal modalities; and (ii) Wernicke’s aphasia, associated with poor auditory–verbal comprehension and repetition, plus fluent speech with jargon. However, the varieties of these comprehension problems, and their underlying causes, are not well understood. Both patient groups exhibit some type of semantic ‘access’ deficit, as opposed to the ‘storage’ deficits observed in semantic dementia. Nevertheless, existing descriptions suggest that these patients might have different varieties of ‘access’ impairment—related to difficulty resolving competition (in semantic aphasia) versus initial activation of concepts from sensory inputs (in Wernicke’s aphasia). We used a case series design to compare patients with Wernicke’s aphasia and those with semantic aphasia on Warrington’s paradigmatic assessment of semantic ‘access’ deficits. In these verbal and non-verbal matching tasks, a small set of semantically-related items are repeatedly presented over several cycles so that the target on one trial becomes a distractor on another (building up interference and eliciting semantic ‘blocking’ effects). Patients with Wernicke’s aphasia and semantic aphasia were distinguished according to lesion location in the temporal cortex, but in each group, some individuals had additional prefrontal damage. Both of these aspects of lesion variability—one that mapped onto classical ‘syndromes’ and one that did not—predicted aspects of the semantic ‘access’ deficit. Both semantic aphasia and Wernicke’s aphasia cases showed multimodal semantic impairment, although as expected, the Wernicke’s aphasia group showed greater deficits on auditory-verbal than picture judgements. Distribution of damage in the temporal lobe was crucial for predicting the initially

  5. Preservation of episodic memory in semantic dementia: The importance of regions beyond the medial temporal lobes.

    Science.gov (United States)

    Irish, Muireann; Bunk, Steffie; Tu, Sicong; Kamminga, Jody; Hodges, John R; Hornberger, Michael; Piguet, Olivier

    2016-01-29

    Episodic memory impairment represents one of the hallmark clinical features of patients with Alzheimer's disease (AD) attributable to the degeneration of medial temporal and parietal regions of the brain. In contrast, a somewhat paradoxical profile of relatively intact episodic memory, particularly for non-verbal material, is observed in semantic dementia (SD), despite marked atrophy of the hippocampus. This retrospective study investigated the neural substrates of episodic memory retrieval in 20 patients with a diagnosis of SD and 21 disease-matched cases of AD and compared their performance to that of 35 age- and education-matched healthy older Controls. Participants completed the Rey Complex Figure and the memory subscale of the Addenbrooke's Cognitive Examination-Revised as indices of visual and verbal episodic recall, respectively. Relative to Controls, AD patients showed compromised memory performance on both visual and verbal memory tasks. In contrast, memory deficits in SD were modality-specific occurring exclusively on the verbal task. Controlling for semantic processing ameliorated these deficits in SD, while memory impairments persisted in AD. Voxel-based morphometry analyses revealed significant overlap in the neural correlates of verbal episodic memory in AD and SD with predominantly anteromedial regions, including the bilateral hippocampus, strongly implicated. Controlling for semantic processing negated this effect in SD, however, a distributed network of frontal, medial temporal, and parietal regions was implicated in AD. Our study corroborates the view that episodic memory deficits in SD arise very largely as a consequence of the conceptual loading of traditional tasks. We propose that the functional integrity of frontal and parietal regions enables new learning to occur in SD in the face of significant hippocampal and anteromedial temporal lobe pathology, underscoring the inherent complexity of the episodic memory circuitry. Copyright © 2015

  6. Cooking "shrimp à la créole": a pilot study of an ecological rehabilitation in semantic dementia.

    Science.gov (United States)

    Bier, Nathalie; Macoir, Joël; Joubert, Sven; Bottari, Carolina; Chayer, Céline; Pigot, Hélène; Giroux, Sylvain

    2011-08-01

    New learning in semantic dementia (SD) seems to be tied to a specific temporal and spatial context. Thus, cognitive rehabilitation could capitalise upon preserved episodic memory and focus on everyday activities which, once learned, will have an impact in everyday life. This pilot study thus explores the effectiveness of an ecological approach in one patient suffering from SD. EC, a 68-year-old woman with SD, stopped cooking complex meals due to a substantial loss of knowledge related to all food types. The therapy consisted of preparing a target recipe. She was asked to generate semantic attributes of ingredients found in one target, one control and two no-therapy recipes. The number of recipes cooked by EC between therapy sessions was computed. She was also asked to prepare a generalisation recipe combining ingredients from the target and control recipes. EC's generated semantic attributes (GSA) of ingredients pertaining to the target and control recipes increased significantly (p recipes (ps > .79). The proportion of meals cooked also increased significantly (p = .021). For the generalisation recipe, she could not succeed without assistance. Frequent food preparation may have provided EC with new memories about the context, usage and appearance of some concepts. These memories seem very context-bound, but EC nonetheless re-introduced some recipes into her day-to-day life. The impact of these results on the relationship between semantic, episodic and procedural memory is discussed, as well as the relevance of an ecological approach in SD.

  7. Language and Dementia: Neuropsychological Aspects.

    Science.gov (United States)

    Kempler, Daniel; Goral, Mira

    2008-01-01

    This article reviews recent evidence for the relationship between extralinguistic cognitive and language abilities in dementia. A survey of data from investigations of three dementia syndromes (Alzheimer's disease, semantic dementia and progressive nonfluent aphasia) reveals that, more often than not, deterioration of conceptual organization appears associated with lexical impairments, whereas impairments in executive function are associated with sentence- and discourse-level deficits. These connections between extralinguistic functions and language ability also emerge from the literature on cognitive reserve and bilingualism that investigates factors that delay the onset and possibly the progression of neuropsychological manifestation of dementia.

  8. Episodic future thinking in semantic dementia: a cognitive and FMRI study.

    Directory of Open Access Journals (Sweden)

    Armelle Viard

    Full Text Available Semantic dementia (SD is characterized by gradual loss of semantic memory. While episodic autobiographical memory seems relatively preserved, behavioral studies suggest that episodic future thinking is impaired. We used fMRI to measure brain activity in four SD patients (JPL, EP, LL, EG while they envisioned future events and remembered personal past events. Twelve healthy elders served as controls. Episodic quality, emotion, mental imagery and level of consciousness (via remember/know judgements were checked at debriefing. We analyzed the future compared to the past for each patient. All patients presented lateral temporal atrophy, but varied in terms of frontal and anterior hippocampal atrophy. Patient JPL presented atrophy in bilateral superior medial frontal gyri and left anterior hippocampus and was unable to engage in episodic future thinking, despite hyperactivations in frontal and occipital regions. Patient EP presented no atrophy in the anterior hippocampus, but atrophy in bilateral superior medial frontal gyrus and had difficulties to engage in episodic future thinking. Patient LL presented atrophy in left anterior hippocampus, but hyperactivated its right counterpart for future compared to past thinking, permitting her to project efficiently in the future in an episodic way. Patient EG presented no atrophy in the superior medial frontal gyri or anterior hippocampi and was able to engage in episodic future thinking. Altogether, patients' future projections differed depending on the severity and localization of their atrophy. The functional integrity of bilateral superior medial frontal gyri and anterior hippocampus appear crucial for episodic future thinking: atrophy of both structures strongly impairs future projection, while integrity of these structures or hyperactivation of residual tissue normalizes episodic future projection.

  9. Semantic memory is impaired in patients with unilateral anterior temporal lobe resection for temporal lobe epilepsy.

    Science.gov (United States)

    Lambon Ralph, Matthew A; Ehsan, Sheeba; Baker, Gus A; Rogers, Timothy T

    2012-01-01

    Contemporary clinical and basic neuroscience studies have increasingly implicated the anterior temporal lobe regions, bilaterally, in the formation of coherent concepts. Mounting convergent evidence for the importance of the anterior temporal lobe in semantic memory is found in patients with bilateral anterior temporal lobe damage (e.g. semantic dementia), functional neuroimaging and repetitive transcranial magnetic stimulation studies. If this proposal is correct, then one might expect patients with anterior temporal lobe resection for long-standing temporal lobe epilepsy to be semantically impaired. Such patients, however, do not present clinically with striking comprehension deficits but with amnesia and variable anomia, leading some to conclude that semantic memory is intact in resection for temporal lobe epilepsy and thus casting doubt over the conclusions drawn from semantic dementia and linked basic neuroscience studies. Whilst there is a considerable neuropsychological literature on temporal lobe epilepsy, few studies have probed semantic memory directly, with mixed results, and none have undertaken the same type of systematic investigation of semantic processing that has been conducted with other patient groups. In this study, therefore, we investigated the semantic performance of 20 patients with resection for chronic temporal lobe epilepsy with a full battery of semantic assessments, including more sensitive measures of semantic processing. The results provide a bridge between the current clinical observations about resection for temporal lobe epilepsy and the expectations from semantic dementia and other neuroscience findings. Specifically, we found that on simple semantic tasks, the patients' accuracy fell in the normal range, with the exception that some patients with left resection for temporal lobe epilepsy had measurable anomia. Once the semantic assessments were made more challenging, by probing specific-level concepts, lower frequency

  10. Multimodal cuing of autobiographical memory in semantic dementia.

    Science.gov (United States)

    Greenberg, Daniel L; Ogar, Jennifer M; Viskontas, Indre V; Gorno Tempini, Maria Luisa; Miller, Bruce; Knowlton, Barbara J

    2011-01-01

    Individuals with semantic dementia (SD) have impaired autobiographical memory (AM), but the extent of the impairment has been controversial. According to one report (Westmacott, Leach, Freedman, & Moscovitch, 2001), patient performance was better when visual cues were used instead of verbal cues; however, the visual cues used in that study (family photographs) provided more retrieval support than do the word cues that are typically used in AM studies. In the present study, we sought to disentangle the effects of retrieval support and cue modality. We cued AMs of 5 patients with SD and 5 controls with words, simple pictures, and odors. Memories were elicited from childhood, early adulthood, and recent adulthood; they were scored for level of detail and episodic specificity. The patients were impaired across all time periods and stimulus modalities. Within the patient group, words and pictures were equally effective as cues (Friedman test; χ² = 0.25, p = .61), whereas odors were less effective than both words and pictures (for words vs. odors, χ² = 7.83, p = .005; for pictures vs. odors, χ² = 6.18, p = .01). There was no evidence of a temporal gradient in either group (for patients with SD, χ² = 0.24, p = .89; for controls, χ² < 2.07, p = .35). Once the effect of retrieval support is equated across stimulus modalities, there is no evidence for an advantage of visual cues over verbal cues. The greater impairment for olfactory cues presumably reflects degeneration of anterior temporal regions that support olfactory memory. (c) 2010 APA, all rights reserved.

  11. Physiological phenotyping of dementias using emotional sounds.

    Science.gov (United States)

    Fletcher, Phillip D; Nicholas, Jennifer M; Shakespeare, Timothy J; Downey, Laura E; Golden, Hannah L; Agustus, Jennifer L; Clark, Camilla N; Mummery, Catherine J; Schott, Jonathan M; Crutch, Sebastian J; Warren, Jason D

    2015-06-01

    Emotional behavioral disturbances are hallmarks of many dementias but their pathophysiology is poorly understood. Here we addressed this issue using the paradigm of emotionally salient sounds. Pupil responses and affective valence ratings for nonverbal sounds of varying emotional salience were assessed in patients with behavioral variant frontotemporal dementia (bvFTD) (n = 14), semantic dementia (SD) (n = 10), progressive nonfluent aphasia (PNFA) (n = 12), and AD (n = 10) versus healthy age-matched individuals (n = 26). Referenced to healthy individuals, overall autonomic reactivity to sound was normal in Alzheimer's disease (AD) but reduced in other syndromes. Patients with bvFTD, SD, and AD showed altered coupling between pupillary and affective behavioral responses to emotionally salient sounds. Emotional sounds are a useful model system for analyzing how dementias affect the processing of salient environmental signals, with implications for defining pathophysiological mechanisms and novel biomarker development.

  12. Episodic Future Thinking in Semantic Dementia: A Cognitive and fMRI Study

    Science.gov (United States)

    Viard, Armelle; Piolino, Pascale; Belliard, Serge; de La Sayette, Vincent; Desgranges, Béatrice; Eustache, Francis

    2014-01-01

    Semantic dementia (SD) is characterized by gradual loss of semantic memory. While episodic autobiographical memory seems relatively preserved, behavioral studies suggest that episodic future thinking is impaired. We used fMRI to measure brain activity in four SD patients (JPL, EP, LL, EG) while they envisioned future events and remembered personal past events. Twelve healthy elders served as controls. Episodic quality, emotion, mental imagery and level of consciousness (via remember/know judgements) were checked at debriefing. We analyzed the future compared to the past for each patient. All patients presented lateral temporal atrophy, but varied in terms of frontal and anterior hippocampal atrophy. Patient JPL presented atrophy in bilateral superior medial frontal gyri and left anterior hippocampus and was unable to engage in episodic future thinking, despite hyperactivations in frontal and occipital regions. Patient EP presented no atrophy in the anterior hippocampus, but atrophy in bilateral superior medial frontal gyrus and had difficulties to engage in episodic future thinking. Patient LL presented atrophy in left anterior hippocampus, but hyperactivated its right counterpart for future compared to past thinking, permitting her to project efficiently in the future in an episodic way. Patient EG presented no atrophy in the superior medial frontal gyri or anterior hippocampi and was able to engage in episodic future thinking. Altogether, patients' future projections differed depending on the severity and localization of their atrophy. The functional integrity of bilateral superior medial frontal gyri and anterior hippocampus appear crucial for episodic future thinking: atrophy of both structures strongly impairs future projection, while integrity of these structures or hyperactivation of residual tissue normalizes episodic future projection. PMID:25333997

  13. Hippocampal subfield volumetry in mild cognitive impairment, Alzheimer's disease and semantic dementia.

    Science.gov (United States)

    La Joie, Renaud; Perrotin, Audrey; de La Sayette, Vincent; Egret, Stéphanie; Doeuvre, Loïc; Belliard, Serge; Eustache, Francis; Desgranges, Béatrice; Chételat, Gaël

    2013-01-01

    Hippocampal atrophy is a well-known feature of Alzheimer's disease (AD), but sensitivity and specificity of hippocampal volumetry are limited. Neuropathological studies have shown that hippocampal subfields are differentially vulnerable to AD; hippocampal subfield volumetry may thus prove to be more accurate than global hippocampal volumetry to detect AD. CA1, subiculum and other subfields were manually delineated from 40 healthy controls, 18 AD, 17 amnestic Mild Cognitive Impairment (aMCI), and 8 semantic dementia (SD) patients using a previously developed high resolution MRI procedure. Non-parametric group comparisons and receiver operating characteristic (ROC) analyses were conducted. Complementary analyses were conducted to evaluate differences of hemispheric asymmetry and anterior-predominance between AD and SD patients and to distinguish aMCI patients with or without β-amyloid deposition as assessed by Florbetapir-TEP. Global hippocampi were atrophied in all three patient groups and volume decreases were maximal in the CA1 subfield (22% loss in aMCI, 27% in both AD and SD; all p volumetry was more accurate than global hippocampal measurement to distinguish patients from controls (areas under the ROC curve = 0.88 and 0.76, respectively; p = 0.05) and preliminary analyses suggest that it was independent from the presence of β-amyloid deposition. In patients with SD, whereas the degree of CA1 and subiculum atrophy was similar to that found in AD patients, hemispheric and anterior-posterior asymmetry were significantly more marked than in AD with greater involvement of the left and anterior hippocampal subfields. The findings suggest that CA1 measurement is more sensitive than global hippocampal volumetry to detect structural changes at the pre-dementia stage, although the predominance of CA1 atrophy does not appear to be specific to AD pathophysiological processes.

  14. Longitudinal patterns of semantic and episodic memory in frontotemporal lobar degeneration and Alzheimer's disease.

    Science.gov (United States)

    Xie, Sharon X; Libon, David J; Wang, Xingmei; Massimo, Lauren; Moore, Peachie; Vesely, Luisa; Khan, Alea; Chatterjee, Anjan; Coslett, H Branch; Hurtig, Howard I; Liang, Tsao-Wei; Grossman, Murray

    2010-03-01

    The longitudinal assessment of episodic and semantic memory was obtained from 236 patients diagnosed with Alzheimer's disease (AD, n = 128) and with frontotemporal lobar degeneration (FTLD, n = 108), including patients with a social comportment/dysexecutive (SOC/EXEC) disorder, progressive nonfluent aphasia (PNFA), semantic dementia (SemD), and corticobasal syndrome (CBS). At the initial assessment, AD patients obtained a lower score on the delayed free recall test than other patients. Longitudinal analyses for delayed free recall found converging performance, with all patients reaching the same level of impairment as AD patients. On the initial evaluation for delayed recognition, AD patients also obtained lower scores than other groups. Longitudinal analyses for delayed recognition test performance found that AD patients consistently produced lower scores than other groups and no convergence between AD and other dementia groups was seen. For semantic memory, there were no initial between-group differences. However, longitudinal analyses for semantic memory revealed group differences over illness duration, with worse performance for SemD versus AD, PNFA, SOC/EXEC, and CBS patients. These data suggest the presence of specific longitudinal patterns of impairment for episodic and semantic memory in AD and FTLD patients suggesting that all forms of dementia do not necessarily converge into a single phenotype.

  15. What dementia reveals about proverb interpretation and its neuroanatomical correlates.

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    Kaiser, Natalie C; Lee, Grace J; Lu, Po H; Mather, Michelle J; Shapira, Jill; Jimenez, Elvira; Thompson, Paul M; Mendez, Mario F

    2013-08-01

    Neuropsychologists frequently include proverb interpretation as a measure of executive abilities. A concrete interpretation of proverbs, however, may reflect semantic impairments from anterior temporal lobes, rather than executive dysfunction from frontal lobes. The investigation of proverb interpretation among patients with different dementias with varying degrees of temporal and frontal dysfunction may clarify the underlying brain-behavior mechanisms for abstraction from proverbs. We propose that patients with behavioral variant frontotemporal dementia (bvFTD), who are characteristically more impaired on proverb interpretation than those with Alzheimer's disease (AD), are disproportionately impaired because of anterior temporal-mediated semantic deficits. Eleven patients with bvFTD and 10 with AD completed the Delis-Kaplan Executive Function System (D-KEFS) Proverbs Test and a series of neuropsychological measures of executive and semantic functions. The analysis included both raw and age-adjusted normed data for multiple choice responses on the D-KEFS Proverbs Test using independent samples t-tests. Tensor-based morphometry (TBM) applied to 3D T1-weighted MRI scans mapped the association between regional brain volume and proverb performance. Computations of mean Jacobian values within select regions of interest provided a numeric summary of regional volume, and voxel-wise regression yielded 3D statistical maps of the association between tissue volume and proverb scores. The patients with bvFTD were significantly worse than those with AD in proverb interpretation. The worse performance of the bvFTD patients involved a greater number of concrete responses to common, familiar proverbs, but not to uncommon, unfamiliar ones. These concrete responses to common proverbs correlated with semantic measures, whereas concrete responses to uncommon proverbs correlated with executive functions. After controlling for dementia diagnosis, TBM analyses indicated significant

  16. A potential protective effect in multilingual patients with semantic dementia: two case reports of patients speaking Taiwanese and Japanese.

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    Liu, Yi-Chien; Yip, Ping-Keung; Fan, Yu-Ming; Meguro, Kenichi

    2012-03-01

    Several reports have suggested that multilingualism has a protective effect against semantic dementia. Here, we provide further evidence for this effect. The patient was a 75-year-old right-handed Taiwanese woman who had retired after working as a tailor. She was able to speak Taiwanese, Japanese and Mandarin Chinese fluently until 5 years ago. She gradually developed symptoms of profound anomia and difficulty with word-finding. Her mother tongue was Taiwanese and she had learned Japanese as her first symbolized language. She had used Mandarin Chinese for most of her life, but depended on Japanese to read and write (such as reading a newspaper and keeping accounts). However, she could now speak only very simple Taiwanese and Japanese, and could recognize only simple Japanese characters. SECOND: The patient was a 62-year-old right-handed man who had worked as an ironworker. He could speak Taiwanese and Mandarin Chinese fluently until 5 years ago. His mother tongue was Taiwanese. After 5 years of language deterioration, he was unable to communicate with his family members or recognize any characters, including numbers. SPECT RESULTS: Brain perfusion ECD SPECT (Tc-99m-ethyl cysteinate dimer single-photon emission computed tomography) showed less perfusion in the multilingual patient (Case #1) than in the bilingual patient (Case #2). Neuropsychological tests also demonstrated a slower rate of degeneration in the multilingual patient. We speculate that reading and writing in Japanese had a greater impact on the semantic system in Case #1. Thus, this patient showed relatively less degeneration or functional inactivity, as shown by perfusion in the frontal lobe, and this might be due to the persistent activation involved in multilingualism.

  17. Sensitivity of the Wechsler Abbreviated Scale of Intelligence-Second Edition (WASI-II) to the neurocognitive deficits associated with the semantic dementia variant of frontotemporal lobar degeneration: A case study.

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    Gontkovsky, Samuel T

    2017-01-01

    This case study of a 71-year-old woman illustrates the clinical utility of the Wechsler Abbreviated Scale of Intelligence-Second Edition (WASI-II) in assessing the neurocognitive sequelae of the semantic dementia variant of frontotemporal lobar degeneration. Obtained scores revealed a decline in estimated Full Scale IQ from the patient's expected premorbid level. Consistent with her initial onset of neuropathology in the left temporal lobe, the WASI-II yielded a difference of 53 standard score points between the Perceptual Reasoning and Verbal Comprehension composites, reflecting the patient's intact capabilities in visuospatial perception and construction in conjunction with marked disturbances of language. The similarities subtest was particularly sensitive to the patient's neurocognitive deficits. WASI-II scores corresponded well with the results obtained from other administered measures, in particular those from the Repeatable Battery for the Assessment of Neuropsychological Status. Findings provide support for use of the WASI-II in the clinical evaluation of semantic dementia and offer preliminary evidence that the test may be helpful in both lateralization and localization of brain lesions.

  18. Analysis of brief language tests in the detection of cognitive decline and dementia

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    Marcia Radanovic

    Full Text Available Abstract Lexical access difficulties are frequent in normal aging and initial stages of dementia. Verbal fluency tests are valuable to detect cognitive decline, evidencing lexico-semantic and executive dysfunction. Objectives: To establish which language tests can contribute in detecting dementia and to verify schooling influence on subject performance. Method: 74 subjects: 33 controls, 17 Clinical Dementia Rating (CDR 0.5 and 24 (Brief Cognitive Battery - BCB e Boston Naming Test - BNT 1 were compared in tests of semantic verbal fluency (animal and fruit, picture naming (BCB and BNT and the language items of Mini Mental State Examination (MMSE. Results: There were significant differences between the control group and both CDR 0.5 and CDR 1 in all tests. Cut-off scores were: 11 and 10 for animal fluency, 8 for fruit fluency (in both, 8 and 9 for BCB naming. The CDR 0.5 group performed better than the CDR 1 group only in animal fluency. Stepwise multiple regression revealed fruit fluency, animal fluency and BCB naming as the best discriminators between patients and controls (specificity: 93.8%; sensitivity: 91.3%. In controls, comparison between illiterates and literates evidenced schooling influence in all tests, except for fruit fluency and BCB naming. In patients with dementia, only fruit fluency was uninfluenced by schooling. Conclusion: The combination of verbal fluency tests in two semantic categories along with a simple picture naming test is highly sensitive in detecting cognitive decline. Comparison between literate and illiterate subjects shows a lesser degree of influence of schooling on the selected tests, thus improving discrimination between low performance and incipient cognitive decline.

  19. Semantic memory and depressive symptoms in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease.

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    Lehrner, J; Coutinho, G; Mattos, P; Moser, D; Pflüger, M; Gleiss, A; Auff, E; Dal-Bianco, P; Pusswald, G; Stögmann, E

    2017-07-01

    Semantic memory may be impaired in clinically recognized states of cognitive impairment. We investigated the relationship between semantic memory and depressive symptoms (DS) in patients with cognitive impairment. 323 cognitively healthy controls and 848 patients with subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer's disease (AD) dementia were included. Semantic knowledge for famous faces, world capitals, and word vocabulary was investigated. Compared to healthy controls, we found a statistically significant difference of semantic knowledge in the MCI groups and the AD group, respectively. Results of the SCD group were mixed. However, two of the three semantic memory measures (world capitals and word vocabulary) showed a significant association with DS. We found a difference in semantic memory performance in MCI and AD as well as an association with DS. Results suggest that the difference in semantic memory is due to a storage loss rather than to a retrieval problem.

  20. [Relearning vocabulary. A comparative analysis between a case of dementia and Alzheimer's disease with predominant compromise of language].

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    Montagut, Núria; Sánchez-Valle, Raquel; Castellví, Magdalena; Rami, Lorena; Molinuevo, José Luis

    Semantic dementia is characterised by a progressive loss of semantic content that initially affects the capacity to name things, and is associated with asymmetric atrophy of the anterior temporal lobes. In Alzheimer's disease (AD) with predominant compromise of language, anomia is also the main symptom. The study examined the capacity to relearn vocabulary of two patients, each exhibiting one of these two forms of degenerative anomia. The two cases presented similar ages, gender, levels of schooling and degree of compromise. Their capacity to name a list of 40 pictures was evaluated at baseline, following 20 sessions of relearning, at one month and at six months. The patient with semantic dementia named 25/40 objects at baseline, 40/40 after relearning, 35/40 at one month and 27/40 at six months. The patient with AD named 29/40 at baseline, 30/40 after relearning, 29/40 at one month and 32/40 at six months. No intrusions were observed following relearning. The patient with semantic dementia was able to relearn all the vocabulary she was shown, even though she lost everything she had acquired after treatment was interrupted. The AD patient did not improve her naming capacity with therapy. These differences suggest that the learning and consolidation circuits are affected in different ways. Subjects with semantic dementia, but not those with AD, could benefit from word relearning strategies with this method.

  1. Domain or Not Domain? That Is the Question: Longitudinal Semantic Deterioration in Alzheimer's Disease

    Science.gov (United States)

    Moreno-Martinez, F. Javier; Goni-Imizcoz, Miguel; Spitznagel, Mary Beth

    2011-01-01

    Category specific semantic impairment (e.g. living versus nonliving things) has been reported in association with various pathologies, including herpes simplex encephalitis and semantic dementia. However, evidence is inconsistent regarding whether this effect exists in diseases progressively impacting diverse cortical regions, such as Alzheimer's…

  2. [Application of spaced retrieval training on patients with dementia].

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    Wu, Hua-Shan; Lin, Li-Chan

    2012-10-01

    Dementia causes semantic and episodic memory impairments that limit patients' activities of daily living (ADL) and increase caregiver burden. Spaced retrieval training uses repetitive retrieval to strengthen cognitive and motor skills intuitively in mild / moderate dementia patients who retain preserved implicit / non-declarative memory. This article describes and discusses the operative mechanism, influencing variables, and practical applications of spaced retrieval training. We hope this article increases professional understanding and application of this training approach to improve dementia patient ADL and improve quality of life for both caregivers and patients.

  3. Anatomical Correlates of Non-Verbal Perception in Dementia Patients

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    Pin-Hsuan Lin

    2016-08-01

    Full Text Available Purpose: Patients with dementia who have dissociations in verbal and non-verbal sound processing may offer insights into the anatomic basis for highly related auditory modes. Methods: To determine the neuronal networks on non-verbal perception, 16 patients with Alzheimer’s dementia (AD, 15 with behavior variant fronto-temporal dementia (bv-FTD, 14 with semantic dementia (SD were evaluated and compared with 15 age-matched controls. Neuropsychological and auditory perceptive tasks were included to test the ability to compare pitch changes, scale-violated melody and for naming and associating with environmental sound. The brain 3D T1 images were acquired and voxel-based morphometry (VBM was used to compare and correlated the volumetric measures with task scores. Results: The SD group scored the lowest among 3 groups in pitch or scale-violated melody tasks. In the environmental sound test, the SD group also showed impairment in naming and also in associating sound with pictures. The AD and bv-FTD groups, compared with the controls, showed no differences in all tests. VBM with task score correlation showed that atrophy in the right supra-marginal and superior temporal gyri was strongly related to deficits in detecting violated scales, while atrophy in the bilateral anterior temporal poles and left medial temporal structures was related to deficits in environmental sound recognition. Conclusions: Auditory perception of pitch, scale-violated melody or environmental sound reflects anatomical degeneration in dementia patients and the processing of non-verbal sounds is mediated by distinct neural circuits.

  4. Are there mental lexicons? The role of semantics in lexical decision.

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    Dilkina, Katia; McClelland, James L; Plaut, David C

    2010-12-13

    What is the underlying representation of lexical knowledge? How do we know whether a given string of letters is a word, whereas another string of letters is not? There are two competing models of lexical processing in the literature. The first proposes that we rely on mental lexicons. The second claims there are no mental lexicons; we identify certain items as words based on semantic knowledge. Thus, the former approach - the multiple-systems view - posits that lexical and semantic processing are subserved by separate systems, whereas the latter approach - the single-system view - holds that the two are interdependent. Semantic dementia patients, who have a cross-modal semantic impairment, show an accompanying and related lexical deficit. These findings support the single-system approach. However, a report of an SD patient whose impairment on lexical decision was not related to his semantic deficits in item-specific ways has presented a challenge to this view. If the two types of processing rely on a common system, then shouldn't damage impair the same items on all tasks? We present a single-system model of lexical and semantic processing, where there are no lexicons, and performance on lexical decision involves the activation of semantic representations. We show how, when these representations are damaged, accuracy on semantic and lexical tasks falls off together, but not necessarily on the same set of items. These findings are congruent with the patient data. We provide an explicit explanation of this pattern of results in our model, by defining and measuring the effects of two orthogonal factors - spelling consistency and concept consistency. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Exploring the content and quality of episodic future simulations in semantic dementia.

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    Irish, Muireann; Addis, Donna Rose; Hodges, John R; Piguet, Olivier

    2012-12-01

    Semantic dementia (SD) is a progressive neurodegenerative disorder characterised by the amodal loss of semantic knowledge in the context of relatively preserved recent episodic memory. Recent studies have demonstrated that despite relatively intact episodic memory the capacity for future simulation in SD is profoundly impaired, resulting in an asymmetric profile where past retrieval is significantly better than future simulation (referred to as a past>future effect). Here, we sought to identify the origins of this asymmetric profile by conducting a fine-grained analysis of the contextual details provided during past retrieval and future simulation in SD. Participants with SD (n=14), Alzheimer's disease (n=11), and healthy controls (n=14) had previously completed an experimental past-future interview in which they generated three past events from the previous year, and three future events in the next year, and provided subjective qualitative ratings of vividness, emotional valence, emotional intensity, task difficulty, and personal significance for each event described. Our results confirmed the striking impairment for future simulation in SD, despite a relative preservation of past episodic retrieval. Examination of the contextual details provided for past memories and future simulations revealed significant impairments irrespective of contextual detail type for future simulations in SD, and demonstrated that the future thinking deficit in this cohort was driven by a marked decline in the provision of internal (episodic) event details. In contrast with this past>future effect for internal event details, SD patients displayed a future>past effect for external (non-episodic) event details. Analyses of the qualitative ratings provided for past and future events indicated that SD patients' phenomenological experience did not differ between temporal conditions. Our findings underscore the fact that successful extraction of episodic elements from the past is not

  6. Does semantic impairment explain surface dyslexia? VLSM evidence for a double dissociation between regularization errors in reading and semantic errors in picture naming

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    Sara Pillay

    2014-04-01

    Full Text Available The correlation between semantic deficits and exception word regularization errors ("surface dyslexia" in semantic dementia has been taken as strong evidence for involvement of semantic codes in exception word pronunciation. Rare cases with semantic deficits but no exception word reading deficit have been explained as due to individual differences in reading strategy, but this account is hotly debated. Semantic dementia is a diffuse process that always includes semantic impairment, making lesion localization difficult and independent assessment of semantic deficits and reading errors impossible. We addressed this problem using voxel-based lesion symptom mapping in 38 patients with left hemisphere stroke. Patients were all right-handed, native English speakers and at least 6 months from stroke onset. Patients performed an oral reading task that included 80 exception words (words with inconsistent orthographic-phonologic correspondence, e.g., pint, plaid, glove. Regularization errors were defined as plausible but incorrect pronunciations based on application of spelling-sound correspondence rules (e.g., 'plaid' pronounced as "played". Two additional tests examined explicit semantic knowledge and retrieval. The first measured semantic substitution errors during naming of 80 standard line drawings of objects. This error type is generally presumed to arise at the level of concept selection. The second test (semantic matching required patients to match a printed sample word (e.g., bus with one of two alternative choice words (e.g., car, taxi on the basis of greater similarity of meaning. Lesions were labeled on high-resolution T1 MRI volumes using a semi-automated segmentation method, followed by diffeomorphic registration to a template. VLSM used an ANCOVA approach to remove variance due to age, education, and total lesion volume. Regularization errors during reading were correlated with damage in the posterior half of the middle temporal gyrus and

  7. [Artificial intelligence meeting neuropsychology. Semantic memory in normal and pathological aging].

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    Aimé, Xavier; Charlet, Jean; Maillet, Didier; Belin, Catherine

    2015-03-01

    Artificial intelligence (IA) is the subject of much research, but also many fantasies. It aims to reproduce human intelligence in its learning capacity, knowledge storage and computation. In 2014, the Defense Advanced Research Projects Agency (DARPA) started the restoring active memory (RAM) program that attempt to develop implantable technology to bridge gaps in the injured brain and restore normal memory function to people with memory loss caused by injury or disease. In another IA's field, computational ontologies (a formal and shared conceptualization) try to model knowledge in order to represent a structured and unambiguous meaning of the concepts of a target domain. The aim of these structures is to ensure a consensual understanding of their meaning and a univariant use (the same concept is used by all to categorize the same individuals). The first representations of knowledge in the AI's domain are largely based on model tests of semantic memory. This one, as a component of long-term memory is the memory of words, ideas, concepts. It is the only declarative memory system that resists so remarkably to the effects of age. In contrast, non-specific cognitive changes may decrease the performance of elderly in various events and instead report difficulties of access to semantic representations that affect the semantics stock itself. Some dementias, like semantic dementia and Alzheimer's disease, are linked to alteration of semantic memory. We propose in this paper, using the computational ontologies model, a formal and relatively thin modeling, in the service of neuropsychology: 1) for the practitioner with decision support systems, 2) for the patient as cognitive prosthesis outsourced, and 3) for the researcher to study semantic memory.

  8. Discrete Neural Correlates for the Recognition of Negative Emotions: Insights from Frontotemporal Dementia

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    Kumfor, Fiona; Irish, Muireann; Hodges, John R.; Piguet, Olivier

    2013-01-01

    Patients with frontotemporal dementia have pervasive changes in emotion recognition and social cognition, yet the neural changes underlying these emotion processing deficits remain unclear. The multimodal system model of emotion proposes that basic emotions are dependent on distinct brain regions, which undergo significant pathological changes in frontotemporal dementia. As such, this syndrome may provide important insight into the impact of neural network degeneration upon the innate ability to recognise emotions. This study used voxel-based morphometry to identify discrete neural correlates involved in the recognition of basic emotions (anger, disgust, fear, sadness, surprise and happiness) in frontotemporal dementia. Forty frontotemporal dementia patients (18 behavioural-variant, 11 semantic dementia, 11 progressive nonfluent aphasia) and 27 healthy controls were tested on two facial emotion recognition tasks: The Ekman 60 and Ekman Caricatures. Although each frontotemporal dementia group showed impaired recognition of negative emotions, distinct associations between emotion-specific task performance and changes in grey matter intensity emerged. Fear recognition was associated with the right amygdala; disgust recognition with the left insula; anger recognition with the left middle and superior temporal gyrus; and sadness recognition with the left subcallosal cingulate, indicating that discrete neural substrates are necessary for emotion recognition in frontotemporal dementia. The erosion of emotion-specific neural networks in neurodegenerative disorders may produce distinct profiles of performance that are relevant to understanding the neurobiological basis of emotion processing. PMID:23805313

  9. Comparing different types of source memory attributes in dementia of Alzheimer's type.

    Science.gov (United States)

    Mammarella, Nicola; Fairfield, Beth; Di Domenico, Alberto

    2012-04-01

    Source monitoring (SM) refers to our ability to discriminate between memories from different sources. Twenty healthy high-cognitive functioning older adults, 20 healthy low-cognitive functioning older adults, and 20 older adults with dementia of Alzheimer's type (DAT) were asked to perform a series of SM tasks that varied in terms of the to-be-remembered source attribute (perceptual, spatial, temporal, semantic, social, and affective details). Results indicated that older DAT adults had greater difficulty in SM compared to the healthy control groups, especially with spatial and semantic details. Data are discussed in terms of the SM framework and suggest that poor memory for some types of source information may be considered as an important indicator of clinical memory function when assessing for the presence and severity of dementia.

  10. Insights from child development on the relationship between episodic and semantic memory.

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    Robertson, Erin K; Köhler, Stefan

    2007-11-05

    The present study was motivated by a recent controversy in the neuropsychological literature on semantic dementia as to whether episodic encoding requires semantic processing or whether it can proceed solely based on perceptual processing. We addressed this issue by examining the effect of age-related limitations in semantic competency on episodic memory in 4-6-year-old children (n=67). We administered three different forced-choice recognition memory tests for pictures previously encountered in a single study episode. The tests varied in the degree to which access to semantically encoded information was required at retrieval. Semantic competency predicted recognition performance regardless of whether access to semantic information was required. A direct relation between picture naming at encoding and subsequent recognition was also found for all tests. Our findings emphasize the importance of semantic encoding processes even in retrieval situations that purportedly do not require access to semantic information. They also highlight the importance of testing neuropsychological models of memory in different populations, healthy and brain damaged, at both ends of the developmental continuum.

  11. A figurative proverb test for dementia: rapid detection of disinhibition, excuse and confabulation, causing discommunication.

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    Yamaguchi, Haruyasu; Maki, Yohko; Yamaguchi, Tomoharu

    2011-12-01

    Communicative disability is regarded as a prominent symptom of demented patients, and many studies have been devoted to analyze deficits of lexical-semantic operations in demented patients. However, it is often observed that even patients with preserved lexical-semantic skills might fail in interactive social communication. Whereas social interaction requires pragmatic language skills, pragmatic language competencies in demented subjects have not been well understood. We propose here a brief stress-free test to detect pragmatic language deficits, focusing on non-literal understanding of figurative expression. We hypothesized that suppression of the literal interpretation was required for figurative language interpretation.  We examined 69 demented subjects, 13 subjects with mild cognitive impairment and 61 healthy controls aged 65 years or more. The subjects were asked the meaning of a familiar proverb categorized as a figurative expression. The answers were analyzed based on five factors, and scored from 0 to 5. To consider the influence of cognitive inhibition on proverb comprehension, the scores of the Stroop Colour-Word Test were compared concerning correct and incorrect answers for each factor, respectively. Furthermore, the characteristics of answers were considered in the light of excuse and confabulation qualitatively. The proverb comprehension scores gradually decreased significantly as dementia progressed. The literal interpretation of the proverb, which showed difficulties in figurative language comprehension, was related to disinhibition. The qualitative analysis showed that excuse and confabulation increased as the dementia stage progressed. Deficits in cognitive inhibition partly explains the difficulties in interactive social communication in dementia. With qualitative analysis, asking the meaning of a proverb can be a brief test applied in a clinical setting to evaluate the stage of dementia, and to illustrate disinhibition, confabulation and

  12. Semantic memory assessment in 15 patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Hervieu-Bègue, M; Rouaud, O; Graule Petot, A; Catteau, A; Giroud, M

    2016-01-01

    A total of 30 to 50% of amyotrophic lateral sclerosis patients suffer from cognitive disorders. The aim of the study is to characterize these disorders and to assess semantic memory in non-demented ALS patients. The secondary aim is to look for a link between disease type and neuropsychological characteristics. Patients were followed in an ALS center in Dijon. The following neuropsychological tests were used in this study: Folstein test, BREF test, verbal fluency, Isaac test, GRESEM test and TOP 30 test. Fifteen ALS patients were included. Nine of them (60%) were suffering from a semantic memory disorder. There was no correlation between ALS characteristics and the semantic memory disorder. This is the first study to reveal a semantic memory disorder in ALS. This result accentuates the hypothesis that ALS and semantic dementia are two phenotypes of the same degenerative process linked to TDP 43 proteinopathy. Copyright © 2016. Published by Elsevier Masson SAS.

  13. Frontotemporal Dementias: A Review

    Directory of Open Access Journals (Sweden)

    Wilkins Kirsten

    2007-06-01

    Full Text Available Abstract Dementia is a clinical state characterized by loss of function in multiple cognitive domains. It is a costly disease in terms of both personal suffering and economic loss. Frontotemporal dementia (FTD is the term now preferred over Picks disease to describe the spectrum of non-Alzheimers dementias characterized by focal atrophy of the frontal and anterior temporal regions of the brain. The prevalence of FTD is considerable, though specific figures vary among different studies. It occurs usually in an age range of 35–75 and it is more common in individuals with a positive family history of dementia. The risk factors associated with this disorder include head injury and family history of FTD. Although there is some controversy regarding the further syndromatic subdivision of the different types of FTD, the three major clinical presentations of FTD include: 1 a frontal or behavioral variant (FvFTD, 2 a temporal, aphasic variant, also called Semantic dementia (SD, and 3 a progressive aphasia (PA. These different variants differ in their clinical presentation, cognitive deficits, and affected brain regions. Patients with FTD should have a neuropsychiatric assessment, neuropsychological testing and neuroimaging studies to confirm and clarify the diagnosis. Treatment for this entity consists of behavioral and pharmacological approaches. Medications such as serotonin reuptake inhibitors, antipsychotics, mood stabilizer and other novel treatments have been used in FTD with different rates of success. Further research should be directed at understanding and developing new diagnostic and therapeutic modalities to improve the patients' prognosis and quality of life.

  14. The role of the left anterior temporal lobe in semantic composition vs. semantic memory.

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    Westerlund, Masha; Pylkkänen, Liina

    2014-05-01

    The left anterior temporal lobe (LATL) is robustly implicated in semantic processing by a growing body of literature. However, these results have emerged from two distinct bodies of work, addressing two different processing levels. On the one hand, the LATL has been characterized as a 'semantic hub׳ that binds features of concepts across a distributed network, based on results from semantic dementia and hemodynamic findings on the categorization of specific compared to basic exemplars. On the other, the LATL has been implicated in combinatorial operations in language, as shown by increased activity in this region associated with the processing of sentences and of basic phrases. The present work aimed to reconcile these two literatures by independently manipulating combination and concept specificity within a minimal MEG paradigm. Participants viewed simple nouns that denoted either low specificity (fish) or high specificity categories (trout) presented in either combinatorial (spotted fish/trout) or non-combinatorial contexts (xhsl fish/trout). By combining these paradigms from the two literatures, we directly compared the engagement of the LATL in semantic memory vs. semantic composition. Our results indicate that although noun specificity subtly modulates the LATL activity elicited by single nouns, it most robustly affects the size of the composition effect when these nouns are adjectivally modified, with low specificity nouns eliciting a much larger effect. We conclude that these findings are compatible with an account in which the specificity and composition effects arise from a shared mechanism of meaning specification. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Frontotemporal dementias: Recent advances and current controversies

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    Leyton Cristian

    2010-10-01

    Full Text Available Frontotemporal dementia (FTD syndromes comprise a heterogeneous group of neurodegenerative conditions characterized by atrophy in the frontal and temporal lobes. Three main clinical variants are recognized: Behavioral variant (bv-FTD, Semantic dementia (SD, and Progressive nonfluent aphasia (PNFA. However, logopenic/phonological (LPA variant has been recently described, showing a distinctive pattern of brain atrophy and often associated to Alzheimer′s disease pathology. The diagnosis of FTD is challenging, since there is clinical, pathological, and genetic overlap between the variants and other neurodegenerative diseases, such as motoneuron disease (MND and corticobasal degeneration (CBD. In addition, patients with gene mutations (tau and progranulin display an inconsistent clinical phenotype and the correspondence between the clinical variant and its pathology is unpredictable. New cognitive tests based on social cognition and emotional recognition together with advances in molecular pathology and genetics have contributed to an improved understanding. There is now a real possibility of accurate biomarkers for early diagnosis. The present review concentrates on new insights and debates in FTD.

  16. Free Recall Episodic Memory Performance Predicts Dementia Ten Years prior to Clinical Diagnosis: Findings from the Betula Longitudinal Study

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    Carl-Johan Boraxbekk

    2015-05-01

    Full Text Available Background/Aims: Early dementia diagnosis is a considerable challenge. The present study examined the predictive value of cognitive performance for a future clinical diagnosis of late-onset Alzheimer's disease or vascular dementia in a random population sample. Methods: Cognitive performance was retrospectively compared between three groups of participants from the Betula longitudinal cohort. Group 1 developed dementia 11-22 years after baseline testing (n = 111 and group 2 after 1-10 years (n = 280; group 3 showed no deterioration towards dementia during the study period (n = 2,855. Multinomial logistic regression analysis was used to investigate the predictive value of tests reflecting episodic memory performance, semantic memory performance, visuospatial ability, and prospective memory performance. Results: Age- and education-corrected performance on two free recall episodic memory tests significantly predicted dementia 10 years prior to clinical diagnosis. Free recall performance also predicted dementia 11-22 years prior to diagnosis when controlling for education, but not when age was added to the model. Conclusion: The present results support the suggestion that two free recall-based tests of episodic memory function may be useful for detecting individuals at risk of developing dementia 10 years prior to clinical diagnosis.

  17. Machine learning approaches to diagnosis and laterality effects in semantic dementia discourse.

    Science.gov (United States)

    Garrard, Peter; Rentoumi, Vassiliki; Gesierich, Benno; Miller, Bruce; Gorno-Tempini, Maria Luisa

    2014-06-01

    Advances in automatic text classification have been necessitated by the rapid increase in the availability of digital documents. Machine learning (ML) algorithms can 'learn' from data: for instance a ML system can be trained on a set of features derived from written texts belonging to known categories, and learn to distinguish between them. Such a trained system can then be used to classify unseen texts. In this paper, we explore the potential of the technique to classify transcribed speech samples along clinical dimensions, using vocabulary data alone. We report the accuracy with which two related ML algorithms [naive Bayes Gaussian (NBG) and naive Bayes multinomial (NBM)] categorized picture descriptions produced by: 32 semantic dementia (SD) patients versus 10 healthy, age-matched controls; and SD patients with left- (n = 21) versus right-predominant (n = 11) patterns of temporal lobe atrophy. We used information gain (IG) to identify the vocabulary features that were most informative to each of these two distinctions. In the SD versus control classification task, both algorithms achieved accuracies of greater than 90%. In the right- versus left-temporal lobe predominant classification, NBM achieved a high level of accuracy (88%), but this was achieved by both NBM and NBG when the features used in the training set were restricted to those with high values of IG. The most informative features for the patient versus control task were low frequency content words, generic terms and components of metanarrative statements. For the right versus left task the number of informative lexical features was too small to support any specific inferences. An enriched feature set, including values derived from Quantitative Production Analysis (QPA) may shed further light on this little understood distinction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Frontotemporal dementia and primary progressive aphasia, a review

    Directory of Open Access Journals (Sweden)

    Kirshner HS

    2014-06-01

    Full Text Available Howard S KirshnerDepartment of Neurology, Vanderbilt University Medical Center, Nashville, TN, USAAbstract: Frontotemporal dementias are neurodegenerative diseases in which symptoms of frontal and/or temporal lobe disease are the first signs of the illness, and as the diseases progress, they resemble a focal left hemisphere process such as stroke or traumatic brain injury, even more than a neurodegenerative disease. Over time, some patients develop a more generalized dementia. Four clinical subtypes characterize the predominant presentations of this illness: behavioral or frontal variant FTD, progressive nonfluent aphasia, semantic dementia, and logopenic primary progressive aphasia. These clinical variants correlate with regional patterns of atrophy on brain imaging studies such as MRI and PET scanning, as well as with biochemical and molecular genetic variants of the disorder. The treatment is as yet only symptomatic, but advances in molecular genetics promise new therapies.Keywords: FTD, behavior variant or frontal variant FTD, pick's disease, PPA, progressive nonfluent aphasia

  19. NEUROPSYCHOLOGICAL ASSESSMENT IN THE ALZHEIMER DISEASE: EPISODIC AND SEMANTIC MEMORY

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    Ana Comesaña

    2009-12-01

    Full Text Available This paper aims to review the neuropsychological evaluation process in Alzheimer (AD patients, specifically that related to episodic and semantic memory. Alzheimer-style dementia is the main form of dementia, and is nowadays one of the most important social, cultural and health-related problems. Diagnosis and differentiation from normal aging are difficult in the initial stages, and so neuropsychological evaluation is key. The criteria currently utilized are those of the DSM IV (American Psychiatric Association, 1994 and of the NINCDS-ADRDA (Instituto Nacional para los Desórdenes Neurológicos, de la Comunicación y el Accidente Cerebro Vascular y la Asociación para la Enfermedad de Alzheimer y Desórdenes Relacionados (McKhann G, Drachman D, Folstein M, y col., 1984, and they require that the diagnosis of probable AD be confirmed by neuropsychological evaluation in addition to clinical evaluation and other studies. After the division of long term memory into semantic and episodic memory was made, specific tests were created for their neuropsychological evaluation in different pathologies, including AD. An important contribution to the early detection of memory deterioration typical of such illness was thus made.

  20. Past, present, and prospects: Reflections 40 years on from the selective impairment of semantic memory (Warrington, 1975).

    Science.gov (United States)

    McCarthy, Rosaleen A; Warrington, Elizabeth K

    2016-10-01

    We summarize the main findings and conclusions of Warrington's (1975) paper, The Selective Impairment of Semantic memory, a neuropsychological paper that described three cases with degenerative neurological conditions [Warrington, E. K. (1975). The selective impairment of semantic memory. The Quarterly Journal of Experimental Psychology, 27, 635-657]. We consider the developments that have followed from its publication and give a selective overview of the field in 2014. The initial impact of the paper was on neuropsychological investigations of semantic loss followed some 14 years later by the identification of Semantic Dementia (the condition shown by the original cases) as a distinctive form of degenerative disease with unique clinical and pathological characteristics. We discuss the distinction between disorders of semantic storage and refractory semantic access, the evidence for category- and modality-specific impairments of semantics, and the light that has been shed on the structure and organization of semantic memory. Finally we consider the relationship between semantic memory and the skills of reading and writing, phonological processing, and autobiographical memory.

  1. Apples are not the only fruit: The effects of concept typicality on semantic representation in the anterior temporal lobe

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    Anna M. Woollams

    2012-04-01

    Full Text Available Intuitively, an apple seems a fairly good example of a fruit, whereas an avocado seems less so. The extent to which an exemplar is representative of its category, a variable known as concept typicality, has long been thought to be a key dimension determining semantic representation. Concept typicality is, however, correlated with a number of other variables, in particular age of acquisition and name frequency. Consideration of picture naming accuracy from a large case-series of semantic dementia patients demonstrated strong effects of concept typicality that were maximal in the moderately impaired patients, over and above the impact of age of acquisition and name frequency. Induction of a temporary virtual lesion to the left anterior temporal lobe, the region most commonly affected in semantic dementia, via repetitive Transcranial Magnetic Stimulation produced an enhanced effect of concept typicality in the picture naming of normal participants, but did not affect the magnitude of the age of acquisition or name frequency effects. These results indicate that concept typicality exerts its influence on semantic representations themselves, as opposed to the strength of connections outside the semantic system. To date, there has been little direct exploration of the dimension of concept typicality within connectionist models of intact and impaired conceptual representation, and these findings provide a target for future computational simulation.

  2. Impaired Interoceptive Accuracy in Semantic Variant Primary Progressive Aphasia

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    Charles R. Marshall

    2017-11-01

    Full Text Available BackgroundInteroception (the perception of internal bodily sensations is strongly linked to emotional experience and sensitivity to the emotions of others in healthy subjects. Interoceptive impairment may contribute to the profound socioemotional symptoms that characterize frontotemporal dementia (FTD syndromes, but remains poorly defined.MethodsPatients representing all major FTD syndromes and healthy age-matched controls performed a heartbeat counting task as a measure of interoceptive accuracy. In addition, patients had volumetric MRI for voxel-based morphometric analysis, and their caregivers completed a questionnaire assessing patients’ daily-life sensitivity to the emotions of others.ResultsInteroceptive accuracy was impaired in patients with semantic variant primary progressive aphasia relative to healthy age-matched individuals, but not in behavioral variant frontotemporal dementia and nonfluent variant primary progressive aphasia. Impaired interoceptive accuracy correlated with reduced daily-life emotional sensitivity across the patient cohort, and with atrophy of right insula, cingulate, and amygdala on voxel-based morphometry in the impaired semantic variant group, delineating a network previously shown to support interoceptive processing in the healthy brain.ConclusionInteroception is a promising novel paradigm for defining mechanisms of reduced emotional reactivity, empathy, and self-awareness in neurodegenerative syndromes and may yield objective measures for these complex symptoms.

  3. Dementia in Qatar

    International Nuclear Information System (INIS)

    Hamad, Ahmad I.; Ibrahim, Mohammed A.; Sulaiti, Essa M.

    2004-01-01

    Dementia is the major public health problem among the elderly in developed countries and a growing problem in the underdeveloped countries. There are no published data on dementia in any of the Arab countries. The aim of this study was to determine the different subtypes of dementia among Qataris. A retrospective and prospective ongoing hospital based study in which all medical records of the patients with diagnosis of dementia seen at the Hamad General Hospital, Doha, Qatar, between June 1997 and June 2003, whether inpatient and outpatient were reviewed. Dementia was defined according to diagnostic and statistical manual (DSM) IV criteria. Those who had dementia were evaluated by a psychologist, psychiatrist, neurologist and a geriatrician. All had brain computerized tomography, magnetic resonance imaging or both and routine blood test. Finally, they were classified into sub-types according to the cause of dementia. One of 300 patients, 134 fulfilled the inclusion criteria, most of them were illiterate, married and non-smokers. Among those dementia sub-types were: Alzheimer disease (AD) 39 (29%), vascular dementia (VaD) 30 (22%), mixed AD and VaD 20 (15%) and Parkinson's disease with dementia due to other medical conditions. Our stidy showed that AD is more prevalent than VaD. It also showed that patients and their families seek medical help late due to to the general belief among the public that forgetfulness and other associated cognitive impairment are part of normal aging process. The emergence of new drugs and advancement in prevention of cerebrovascular diseases make early diagnosis of dementia sub-type important. A community based study to show the real prevalence and incidence of sub-types of dementia is highly indicated. These data are necessory for planning and setting up community services and health care programs for demented patients. (author)

  4. Risk factors for delusion of theft in patients with Alzheimer's disease showing mild dementia in Japan.

    Science.gov (United States)

    Murayama, N; Iseki, E; Endo, T; Nagashima, K; Yamamoto, R; Ichimiya, Y; Arai, H; Sato, K

    2009-07-01

    The mechanism underlying delusion in Alzheimer's disease patients has not been fully clarified; however, the occurrence of delusion is a critical issue for dementia patients and their caregivers. In Japan, delusion of theft is the most frequent delusion in AD patients. We examined the risk factors for delusion of theft in AD patients showing mild dementia. Fifty-six AD patients were administered HDS-R, MMSE and COGNISTAT, including the 'speech sample', to assess their neuropsychological and social cognitive functions. The age, years of education, presence of cohabiting family members and premorbid personality traits were obtained from family members. About 25.0% of AD patients showed delusion of theft (D-group), and 75% did not (non-D-group). About 33.3% of female patients and 5.9% of male patients were included in the D-group (p theft in AD patients was related to female gender, absence of cohabiting family members, neurotic personality and retained social cognitive function.

  5. VALIDITY OF THE CONNECTION INTER-LEXICAL A-SEMANTICS IN THE COGNITIVE MODEL OF PROCESSING PRAXIS

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    P. G. Gómez

    2011-07-01

    Full Text Available Rothia Gonzalez et al. (1991, 1997 postulated a cognitive model of praxis on which changes were proposed (Cubelli et al., 2000, including the removal of the direct path between both input praxicon and output. Was suggested that to validate an inter-lexical a-semantics path (Cubelli et al., 2000 would enough to find a patientwith preserved ability for imitate familiar gestures, but with disturbances in the ability to access to the meaning of familiar gestures and alterations in ability for imitate unfamiliar gestures. The aim of this work is present two patients whose patterns ofperformance on praxis supports the existence of a pathway inter-lexical a-semantic. We evaluated two patients with Alzheimer type dementia unlikely with a battery of cognitive assessment of apraxia (Politis 2003. Both patients show alterations in test of Imitation of unfamiliar gestures and on tasks which assess semantic action objecttool watching and naming by function, with good performance on the task of imitating familiar gestures. Based on cognitive models of praxis Rothia Gonzalez et al. (1991, 1997 and Cubelli et al. (2000 is require a direct connection between both input praxicon and output to explain the performance of these patients. Of thus, the performance pattern showing both patients confirms existence of a pathway.Interlexical asemantics

  6. Music and dementia.

    Science.gov (United States)

    Baird, Amee; Samson, Séverine

    2015-01-01

    There is an increasing incidence of dementia in our aging population, and consequently an urgent need to develop treatments and activities that may alleviate the symptoms of dementia. Accumulating evidence shows that persons with dementia enjoy music, and their ability to respond to music is potentially preserved even in the late or severe stages of dementia when verbal communication may have ceased. Media interest in this topic has contributed to the public perception that music abilities are an "island of preservation" in an otherwise cognitively impaired person with dementia. In this chapter, we review the current literature on music cognition in dementia and show that there has been very scarce rigorous scientific investigation of this issue, and that various types of music memory exist and are differentially impaired in the different types of dementia. Furthermore, we discuss the recent development of music activities as a nonpharmacological treatment for dementia and highlight the methodological limitations of the current literature on this topic. While it has been reported that music activities can improve behavior, (particularly agitation), mood, and cognition in persons with dementia, recent large-scale randomized control studies have questioned the specificity of the effect of music and found that it is no more beneficial than other pleasant activities. Nevertheless, music is unique in its powerful ability to elicit both memories and emotions. This can provide an important link to individual's past and a means of nonverbal communication with carers, which make it an ideal stimulus for persons with dementia. © 2015 Elsevier B.V. All rights reserved.

  7. On Which Abilities Are Category Fluency and Letter Fluency Grounded A Confirmatory Factor Analysis of 53 Alzheimer's Dementia Patients

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    Ilaria Bizzozero

    2013-05-01

    Full Text Available Background/Aims: In Alzheimer's dementia (AD, letter fluency is less impaired than category fluency. To check whether category fluency and letter fluency depend differently on semantics and attention, 53 mild AD patients were given animal and letter fluency tasks, two semantic tests (the Verbal Semantic Questionnaire and the BORB Association Match test, and two attentional tests (the Stroop Colour-Word Interference test and the Digit Cancellation test. Methods: We conducted a LISREL confirmatory factor analysis to check the extent to which category fluency and letter fluency tasks were related to semantics and attention, viewed as latent variables. Results: Both types of fluency tasks were related to the latent variable Semantics but not to the latent variable Attention. Conclusions: Our findings warn against interpreting the disproportionate impairment of AD patients on category and letter fluency as a contrast between semantics and attention.

  8. Newly-acquired words are more phonologically robust in verbal short-term memory when they have associated semantic representations.

    Science.gov (United States)

    Savill, Nicola; Ellis, Andrew W; Jefferies, Elizabeth

    2017-04-01

    Verbal short-term memory (STM) is a crucial cognitive function central to language learning, comprehension and reasoning, yet the processes that underlie this capacity are not fully understood. In particular, although STM primarily draws on a phonological code, interactions between long-term phonological and semantic representations might help to stabilise the phonological trace for words ("semantic binding hypothesis"). This idea was first proposed to explain the frequent phoneme recombination errors made by patients with semantic dementia when recalling words that are no longer fully understood. However, converging evidence in support of semantic binding is scant: it is unusual for studies of healthy participants to examine serial recall at the phoneme level and also it is difficult to separate the contribution of phonological-lexical knowledge from effects of word meaning. We used a new method to disentangle these influences in healthy individuals by training new 'words' with or without associated semantic information. We examined phonological coherence in immediate serial recall (ISR), both immediately and the day after training. Trained items were more likely to be recalled than novel nonwords, confirming the importance of phonological-lexical knowledge, and items with semantic associations were also produced more accurately than those with no meaning, at both time points. For semantically-trained items, there were fewer phoneme ordering and identity errors, and consequently more complete target items were produced in both correct and incorrect list positions. These data show that lexical-semantic knowledge improves the robustness of verbal STM at the sub-item level, even when the effect of phonological familiarity is taken into account. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Observing conversational laughter in frontotemporal dementia.

    Science.gov (United States)

    Pressman, Peter S; Simpson, Michaela; Gola, Kelly; Shdo, Suzanne M; Spinelli, Edoardo G; Miller, Bruce L; Gorno-Tempini, Maria Luisa; Rankin, Katherine; Levenson, Robert W

    2017-05-01

    We performed an observational study of laughter during seminaturalistic conversations between patients with dementia and familial caregivers. Patients were diagnosed with (1) behavioural variant frontotemporal dementia (bvFTD), (2) right temporal variant frontotemporal dementia (rtFTD), (3) semantic variant of primary progressive aphasia (svPPA), (4) non-fluent variant primary progressive aphasia (nfvPPA) or (5) early onset Alzheimer's disease (eoAD). We hypothesised that those with bvFTD would laugh less in response to their own speech than other dementia groups or controls, while those with rtFTD would laugh less regardless of who was speaking. Patients with bvFTD (n=39), svPPA (n=19), rtFTD (n=14), nfvPPA (n=16), eoAD (n=17) and healthy controls (n=156) were recorded (video and audio) while discussing a problem in their relationship with a healthy control companion. Using the audio track only, laughs were identified by trained coders and then further classed by an automated algorithm as occurring during or shortly after the participant's own vocalisation ('self' context) or during or shortly after the partner's vocalisation ('partner' context). Individuals with bvFTD, eoAD or rtFTD laughed less across both contexts of self and partner than the other groups. Those with bvFTD laughed less relative to their own speech comparedwith healthy controls. Those with nfvPPA laughed more in the partner context compared with healthy controls. Laughter in response to one's own vocalisations or those of a conversational partner may be a clinically useful measure in dementia diagnosis. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. Causality in the semantics of Esterel : revisited

    NARCIS (Netherlands)

    Mousavi, M.R.; Klin, B.; Sobocinski, P.

    2010-01-01

    We re-examine the challenges concerning causality in the semantics of Esterel and show that they pertain to the known issues in the semantics of Structured Operational Semantics with negative premises. We show that the solutions offered for the semantics of SOS also provide answers to the semantic

  11. Trust estimation of the semantic web using semantic web clustering

    Science.gov (United States)

    Shirgahi, Hossein; Mohsenzadeh, Mehran; Haj Seyyed Javadi, Hamid

    2017-05-01

    Development of semantic web and social network is undeniable in the Internet world these days. Widespread nature of semantic web has been very challenging to assess the trust in this field. In recent years, extensive researches have been done to estimate the trust of semantic web. Since trust of semantic web is a multidimensional problem, in this paper, we used parameters of social network authority, the value of pages links authority and semantic authority to assess the trust. Due to the large space of semantic network, we considered the problem scope to the clusters of semantic subnetworks and obtained the trust of each cluster elements as local and calculated the trust of outside resources according to their local trusts and trust of clusters to each other. According to the experimental result, the proposed method shows more than 79% Fscore that is about 11.9% in average more than Eigen, Tidal and centralised trust methods. Mean of error in this proposed method is 12.936, that is 9.75% in average less than Eigen and Tidal trust methods.

  12. Semantic Versus Syntactic Cutting Planes

    OpenAIRE

    Filmus, Yuval; Hrubeš, Pavel; Lauria, Massimo

    2016-01-01

    In this paper, we compare the strength of the semantic and syntactic version of the cutting planes proof system. First, we show that the lower bound technique of Pudlák applies also to semantic cutting planes: the proof system has feasible interpolation via monotone real circuits, which gives an exponential lower bound on lengths of semantic cutting planes refutations. Second, we show that semantic refutations are stronger than syntactic ones. In particular, we give a formula for whic...

  13. Personal semantics: at the crossroads of semantic and episodic memory.

    Science.gov (United States)

    Renoult, Louis; Davidson, Patrick S R; Palombo, Daniela J; Moscovitch, Morris; Levine, Brian

    2012-11-01

    Declarative memory is usually described as consisting of two systems: semantic and episodic memory. Between these two poles, however, may lie a third entity: personal semantics (PS). PS concerns knowledge of one's past. Although typically assumed to be an aspect of semantic memory, it is essentially absent from existing models of knowledge. Furthermore, like episodic memory (EM), PS is idiosyncratically personal (i.e., not culturally-shared). We show that, depending on how it is operationalized, the neural correlates of PS can look more similar to semantic memory, more similar to EM, or dissimilar to both. We consider three different perspectives to better integrate PS into existing models of declarative memory and suggest experimental strategies for disentangling PS from semantic and episodic memory. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. An Island of Stability: Art Images and Natural Scenes - but Not Natural Faces - Show Consistent Esthetic Response in Alzheimer's-Related Dementia.

    Science.gov (United States)

    Graham, Daniel J; Stockinger, Simone; Leder, Helmut

    2013-01-01

    Alzheimer's disease (AD) causes severe impairments in cognitive function but there is evidence that aspects of esthetic perception are somewhat spared, at least in early stages of the disease. People with early Alzheimer's-related dementia have been found to show similar degrees of stability over time in esthetic judgment of paintings compared to controls, despite poor explicit memory for the images. Here we expand on this line of inquiry to investigate the types of perceptual judgments involved, and to test whether people in later stages of the disease also show evidence of preserved esthetic judgment. Our results confirm that, compared to healthy controls, there is similar esthetic stability in early stage AD in the absence of explicit memory, and we report here that people with later stages of the disease also show similar stability compared to controls. However, while we find that stability for portrait paintings, landscape paintings, and landscape photographs is not different compared to control group performance, stability for face photographs - which were matched for identity with the portrait paintings - was significantly impaired in the AD group. We suggest that partially spared face-processing systems interfere with esthetic processing of natural faces in ways that are not found for artistic images and landscape photographs. Thus, our work provides a novel form of evidence regarding face-processing in healthy and diseased aging. Our work also gives insights into general theories of esthetics, since people with AD are not encumbered by many of the semantic and emotional factors that otherwise color esthetic judgment. We conclude that, for people with AD, basic esthetic judgment of artistic images represents an "island of stability" in a condition that in most other respects causes profound cognitive disruption. As such, esthetic response could be a promising route to future therapies.

  15. When Rey-Osterrieth’s Complex Figure Becomes a Church: Prevalence and Correlates of Graphic Confabulations in Dementia

    Directory of Open Access Journals (Sweden)

    Oriana Pelati

    2011-11-01

    Full Text Available Verbal confabulation (VC has been described in several pathological conditions characterized by amnesia and has been defined as ‘statements that involve distortion of memories’. Here we describe another kind of confabulation (graphic confabulation, GC, evident at the recall of the Rey-Osterrieth complex figure (ROCF. In a retrospective study of 267 patients with mild-to-moderate dementia, 14 patients (4.9 % recalled the abstract ROCF as drawings with recognizable semantic meaning. VC was evident at the story recall test in 19.8% of the study participants. VC and GC were homogeneously distributed among the different types of dementia. VC has been proposed to originate from complex interactions of amnesia, motivational deficit and dysfunction of monitoring systems. On the contrary, GC seems to be the result of a deficit in visual memory replaced by the semantic translation of isolated parts of the ROCF along with a source monitoring deficit.

  16. Semantic impairment disrupts perception, memory, and naming of secondary but not primary colours.

    OpenAIRE

    Rogers, Timothy T.; Graham, Kim S.; Patterson, Karalyn

    2015-01-01

    To investigate how basic aspects of perception are shaped by acquired knowledge about the world, we assessed colour perception and cognition in patients with semantic dementia (SD), a disorder that progressively erodes conceptual knowledge. We observed a previously undocumented pattern of impairment to colour perception and cognition characterized by: (i) a normal ability to discriminate between only subtly different colours but an impaired ability to group different colours into categories, ...

  17. The inferior, anterior temporal lobes and semantic memory clarified: novel evidence from distortion-corrected fMRI.

    Science.gov (United States)

    Visser, M; Embleton, K V; Jefferies, E; Parker, G J; Ralph, M A Lambon

    2010-05-01

    The neural basis of semantic memory generates considerable debate. Semantic dementia results from bilateral anterior temporal lobe (ATL) atrophy and gives rise to a highly specific impairment of semantic memory, suggesting that this region is a critical neural substrate for semantic processing. Recent rTMS experiments with neurologically-intact participants also indicate that the ATL are a necessary substrate for semantic memory. Exactly which regions within the ATL are important for semantic memory are difficult to detect from these methods (because the damage in SD covers a large part of the ATL). Functional neuroimaging might provide important clues about which specific areas exhibit activation that correlates with normal semantic performance. Neuroimaging studies, however, have not consistently found anterior temporal lobe activation in semantic tasks. A recent meta-analysis indicates that this inconsistency may be due to a collection of technical limitations associated with previous studies, including a reduced field-of-view and magnetic susceptibility artefacts associated with standard gradient echo fMRI. We conducted an fMRI study of semantic memory using a combination of techniques which improve sensitivity to ATL activations whilst preserving whole-brain coverage. As expected from SD patients and ATL rTMS experiments, this method revealed bilateral temporal activation extending from the inferior temporal lobe along the fusiform gyrus to the anterior temporal regions, bilaterally. We suggest that the inferior, anterior temporal lobe region makes a crucial contribution to semantic cognition and utilising this version of fMRI will enable further research on the semantic role of the ATL. 2010 Elsevier Ltd. All rights reserved.

  18. Preservation of person-specific knowledge in semantic memory disorder: a longitudinal investigation in two cases of dementia.

    Science.gov (United States)

    Haslam, Catherine; Sabah, Mazen

    2013-03-01

    The double dissociation involving person-specific and general semantic knowledge is supported by numerous patient studies, though cases with preservation of the former are few. In this paper, we report longitudinal data from two cases. Their knowledge in both domains was preserved at the start of the investigation, but progressive deterioration was primarily observed on tests of general semantics. These data strengthen the evidence-base for preservation of person-specific knowledge in semantic memory disorder, and support its separate representation from object knowledge. © 2012 The British Psychological Society.

  19. Brain correlates of musical and facial emotion recognition: evidence from the dementias.

    Science.gov (United States)

    Hsieh, S; Hornberger, M; Piguet, O; Hodges, J R

    2012-07-01

    The recognition of facial expressions of emotion is impaired in semantic dementia (SD) and is associated with right-sided brain atrophy in areas known to be involved in emotion processing, notably the amygdala. Whether patients with SD also experience difficulty recognizing emotions conveyed by other media, such as music, is unclear. Prior studies have used excerpts of known music from classical or film repertoire but not unfamiliar melodies designed to convey distinct emotions. Patients with SD (n = 11), Alzheimer's disease (n = 12) and healthy control participants (n = 20) underwent tests of emotion recognition in two modalities: unfamiliar musical tunes and unknown faces as well as volumetric MRI. Patients with SD were most impaired with the recognition of facial and musical emotions, particularly for negative emotions. Voxel-based morphometry showed that the labelling of emotions, regardless of modality, correlated with the degree of atrophy in the right temporal pole, amygdala and insula. The recognition of musical (but not facial) emotions was also associated with atrophy of the left anterior and inferior temporal lobe, which overlapped with regions correlating with standardized measures of verbal semantic memory. These findings highlight the common neural substrates supporting the processing of emotions by facial and musical stimuli but also indicate that the recognition of emotions from music draws upon brain regions that are associated with semantics in language. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Episodic memory and the medial temporal lobe: not all it seems. Evidence from the temporal variants of frontotemporal dementia

    NARCIS (Netherlands)

    Pleizier, C.M.; van der Vlies, A.E.; Koedam, E.L.G.E.; Koene, T.; Barkhof, F.; van der Flier, W.M.; Scheltens, P.; Pijnenburg, Y.A.L.

    2012-01-01

    Background: Disproportionate medial temporal lobe atrophy (MTA) is an early finding in Alzheimer's disease (AD). Episodic memory impairment in AD is associated with the degree of MTA. Episodic memory impairment and MTA are also found in semantic dementia (SD) and in right temporal lobe atrophy

  1. Demência semântica: avaliação clínica e de neuroimagem. Relato de caso Semantic dementia: clinical and neuroimaging evaluation. Case report

    Directory of Open Access Journals (Sweden)

    Leonardo Caixeta

    2005-06-01

    Full Text Available A demência semântica é uma síndrome clínica que faz parte do grupo das degenerações lobares frontotemporais. Relatamos o caso de um homem de 63 anos que aos 57 anos inicia comprometimento da memória semântica tanto para material visual quanto principalmente verbal. Alterações leves de comportamento estavam presentes e relacionadas com reações exageradas a estímulos dolorosos e comportamentos repetitivos. Os exames de neuroimagem estrutural e funcional evidenciaram comprometimento bitemporal assimétrico, predominando à esquerda. Diagnóstico diferencial deve ser feito com a doença de Alzheimer, outros representantes do grupo das degenerações lobares frontotemporais e qualquer síndrome que se apresente com uma afasia fluente progressiva.Semantic dementia is a clinical syndrome in the spectrum of frontotemporal lobar degeneration group. We report on a 63 years old man who presented with memory disorder of semantic nature for visual and mainly verbal material when he was 57 years old. Mild behavior impairment was present and related to exaggerated responses to algic stimuli and repetitive behavior. Structural and functional neuroimaging methods disclosed asymmetric bitemporal damage, mainly on the left. Differential diagnosis should be considered with Alzheimer's disease, another subtypes of the frontotemporal lobar degeneration group and any other syndrome that presents with a fluent aphasic progressive disorder.

  2. An island of stability: art images and natural scenes—but not natural faces—show consistent aesthetic response in Alzheimer’s-related dementia.

    Directory of Open Access Journals (Sweden)

    Daniel eGraham

    2013-03-01

    Full Text Available Alzheimer’s disease causes severe impairments in cognitive function but there is evidence that aspects of aesthetic perception are somewhat spared, at least in early stages of the disease. People with early Alzheimer’s-related dementia have been found to show similar degrees of stability over time in aesthetic judgment of paintings compared to controls, despite poor explicit memory for the images. Here we expand on this line of inquiry to investigate the types of perceptual judgments involved, and to test whether people in later stages of the disease also show evidence of preserved aesthetic judgment. Our results confirm that, compared to healthy controls, there is similar aesthetic stability in early stage Alzheimer’s disease (AD in the absence of explicit memory, and we report here that people with later stages of the disease also show similar stability compared to controls. However, while we find that stability for portrait paintings, landscape paintings, and landscape photographs is not different compared to control group performance, stability for face photographs—which were matched for identity with the portrait paintings—was significantly impaired in the AD group. We suggest that partially spared face-processing systems interfere with aesthetic processing of natural faces in ways that are not found for artistic images and landscape photographs. Thus, our work provides a novel form of evidence regarding face processing in healthy and diseased ageing. Our work also gives insights into general theories of aesthetics, since people with Alzheimer’s disease are not encumbered by many of the semantic and emotional factors that otherwise color aesthetic judgment. We conclude that, for people with Alzheimer’s disease, basic aesthetic judgment of artistic images represents an island of stability in a condition that in most other respects causes profound cognitive disruption. As such, aesthetic response could be a promising route to

  3. Cross-cultural adaptation of the Social and Emotional Questionnaire on Dementia for the Brazilian population.

    Science.gov (United States)

    Belfort, Tatiana; Bramham, Jessica; Simões Neto, José Pedro; Sousa, Maria Fernanda Barroso de; Santos, Raquel Luiza dos; Nogueira, Marcela Moreira Lima; Torres, Bianca; Rosa, Rachel Dias Lopes da; Dourado, Marcia Cristina Nascimento

    2015-01-01

    Impairments in social and emotional functioning may affect the communication skills and interpersonal relationships of people with dementia and their caregivers. This study had the aim of presenting the steps involved in the cross-cultural adaptation of the Social and Emotional Questionnaire (SEQ) for the Brazilian population. Cross-cultural adaptation study, conducted at the Center for Alzheimer's Disease and Related Disorders in a public university. The process adopted in this study required six consecutive steps: initial translation, translation synthesis, back translation, committee of judges, pretesting of final version and submission to the original author. In general, the items had semantic, idiomatic, conceptual and experiential equivalence. During the first pretest, people with dementia and their caregivers had difficulties in understanding some items relating to social skills, which were interpreted ambiguously. New changes were made to allow better adjustment to the target population and, following this, a new pretest was performed. This pre-test showed that the changes were relevant and gave rise to the final version of the instrument. There was no correlation between education level and performance in the questionnaire, among people with dementia (P = 0.951). The Brazilian Portuguese version of the Social and Emotional Questionnaire was well understood and, despite the cultural and linguistic differences, the constructs of the original version were maintained.

  4. Occult CSF flow disturbance of patients with Alzheimer type dementia and vascular dementia

    International Nuclear Information System (INIS)

    Kono, Kazuhiko; Sugita, Yasuko; Funaki, Chiaki

    1994-01-01

    We report results of Iotrolan CT-cisternography on 41 demented patients (13 males and 28 females) to find 'occult normal pressure hydrocephalus'. These patients were suspected to have CSF flow disturbance from clinical symptoms and simple brain CT scan findings. Their average age, duration of dementia, and score of Hasegawa's dementia scale (HDS) were 76.2 years, 5.9 years, 9.5/32.5,respectively. Before performing CT-cisternography, clinical diagnosis for their dementia were vascular dementia in 18 patients. Alzheimer type dementia in 12, suspect of NPH in 5, and other diagnoses in 6. From the results of cisternography, we found 13 patients with CSF flow disturbance (contrast material remained in the ventricle more than 48 hours after injection), and 17 patients with normal CSF flow. The former showed lower scores of HDS, higher urinary incontinence scores and smaller areas of the interhemispheric fissure on CT scan than the latter. But the former showed no significant difference from the latter in the average age, duration of dementia and width of the ventricles. (author)

  5. Grey and white matter correlates of recent and remote autobiographical memory retrieval--insights from the dementias.

    Directory of Open Access Journals (Sweden)

    Muireann Irish

    Full Text Available The capacity to remember self-referential past events relies on the integrity of a distributed neural network. Controversy exists, however, regarding the involvement of specific brain structures for the retrieval of recently experienced versus more distant events. Here, we explored how characteristic patterns of atrophy in neurodegenerative disorders differentially disrupt remote versus recent autobiographical memory. Eleven behavioural-variant frontotemporal dementia, 10 semantic dementia, 15 Alzheimer's disease patients and 14 healthy older Controls completed the Autobiographical Interview. All patient groups displayed significant remote memory impairments relative to Controls. Similarly, recent period retrieval was significantly compromised in behavioural-variant frontotemporal dementia and Alzheimer's disease, yet semantic dementia patients scored in line with Controls. Voxel-based morphometry and diffusion tensor imaging analyses, for all participants combined, were conducted to investigate grey and white matter correlates of remote and recent autobiographical memory retrieval. Neural correlates common to both recent and remote time periods were identified, including the hippocampus, medial prefrontal, and frontopolar cortices, and the forceps minor and left hippocampal portion of the cingulum bundle. Regions exclusively implicated in each time period were also identified. The integrity of the anterior temporal cortices was related to the retrieval of remote memories, whereas the posterior cingulate cortex emerged as a structure significantly associated with recent autobiographical memory retrieval. This study represents the first investigation of the grey and white matter correlates of remote and recent autobiographical memory retrieval in neurodegenerative disorders. Our findings demonstrate the importance of core brain structures, including the medial prefrontal cortex and hippocampus, irrespective of time period, and point towards the

  6. Subliminal semantic priming in speech.

    Directory of Open Access Journals (Sweden)

    Jérôme Daltrozzo

    Full Text Available Numerous studies have reported subliminal repetition and semantic priming in the visual modality. We transferred this paradigm to the auditory modality. Prime awareness was manipulated by a reduction of sound intensity level. Uncategorized prime words (according to a post-test were followed by semantically related, unrelated, or repeated target words (presented without intensity reduction and participants performed a lexical decision task (LDT. Participants with slower reaction times in the LDT showed semantic priming (faster reaction times for semantically related compared to unrelated targets and negative repetition priming (slower reaction times for repeated compared to semantically related targets. This is the first report of semantic priming in the auditory modality without conscious categorization of the prime.

  7. Patterns of brain atrophy associated with episodic memory and semantic fluency decline in aging.

    Science.gov (United States)

    Pelletier, Amandine; Bernard, Charlotte; Dilharreguy, Bixente; Helmer, Catherine; Le Goff, Melanie; Chanraud, Sandra; Dartigues, Jean-François; Allard, Michèle; Amieva, Hélène; Catheline, Gwénaëlle

    2017-03-09

    The cerebral substratum of age-related cognitive decline was evaluated in an elderly-cohort followed for 12 years (n=306). Participants, free of dementia, received neuropsychological assessments every two years and an MRI exam at baseline and four years later. Cognitive decline was evaluated on two broadly used tests to detect dementia: the Free and Cued Selective Reminding Test (FCSRT), a verbal episodic memory task, and the Isaacs Set Test (IST), a semantic fluency task. Using voxel-based approach, the relationship between cognitive decline with 1/ baseline grey matter volumes and 2/ grey matter volume loss between the two scans was explored. Baseline volumes analysis revealed that FCSRT and IST declines were both associated with lower volumes of the medial temporal region. Volumes loss analysis confirmed that both declines are related to medial temporal lobe atrophy and revealed that FCSRT decline was specifically associated with atrophy of the posterior cingulate cortex whereas IST decline was specifically related to temporal pole atrophy. These results suggest that cognitive decline across aging is firstly related to structural modifications of the medial temporal lobe, followed by an atrophy in the posterior midline structures for episodic memory and an atrophy of the temporal pole for semantic fluency.

  8. Flow Logics and Operational Semantics

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis

    1998-01-01

    Flow logic is a “fast prototyping” approach to program analysis that shows great promise of being able to deal with a wide variety of languages and calculi for computation. However, seemingly innocent choices in the flow logic as well as in the operational semantics may inhibit proving the analys...... correct. Our main conclusion is that environment based semantics is more flexible than either substitution based semantics or semantics making use of structural congruences (like alpha-renaming)....

  9. Prevalence of dementia and major dementia subtypes in Spanish populations: A reanalysis of dementia prevalence surveys, 1990-2008

    Directory of Open Access Journals (Sweden)

    Boix Raquel

    2009-10-01

    Full Text Available Abstract Background This study describes the prevalence of dementia and major dementia subtypes in Spanish elderly. Methods We identified screening surveys, both published and unpublished, in Spanish populations, which fulfilled specific quality criteria and targeted prevalence of dementia in populations aged 70 years and above. Surveys covering 13 geographically different populations were selected (prevalence period: 1990-2008. Authors of original surveys provided methodological details of their studies through a systematic questionnaire and also raw age-specific data. Prevalence data were compared using direct adjustment and logistic regression. Results The reanalyzed study population (aged 70 year and above was composed of Central and North-Eastern Spanish sub-populations obtained from 9 surveys and totaled 12,232 persons and 1,194 cases of dementia (707 of Alzheimer's disease, 238 of vascular dementia. Results showed high variation in age- and sex-specific prevalence across studies. The reanalyzed prevalence of dementia was significantly higher in women; increased with age, particularly for Alzheimer's disease; and displayed a significant geographical variation among men. Prevalence was lowest in surveys reporting participation below 85%, studies referred to urban-mixed populations and populations diagnosed by psychiatrists. Conclusion Prevalence of dementia and Alzheimer's disease in Central and North-Eastern Spain is higher in females, increases with age, and displays considerable geographic variation that may be method-related. People suffering from dementia and Alzheimer's disease in Spain may approach 600,000 and 400,000 respectively. However, existing studies may not be completely appropriate to infer prevalence of dementia and its subtypes in Spain until surveys in Southern Spain are conducted.

  10. Emotion perception, but not affect perception, is impaired with semantic memory loss.

    Science.gov (United States)

    Lindquist, Kristen A; Gendron, Maria; Barrett, Lisa Feldman; Dickerson, Bradford C

    2014-04-01

    For decades, psychologists and neuroscientists have hypothesized that the ability to perceive emotions on others' faces is inborn, prelinguistic, and universal. Concept knowledge about emotion has been assumed to be epiphenomenal to emotion perception. In this article, we report findings from 3 patients with semantic dementia that cannot be explained by this "basic emotion" view. These patients, who have substantial deficits in semantic processing abilities, spontaneously perceived pleasant and unpleasant expressions on faces, but not discrete emotions such as anger, disgust, fear, or sadness, even in a task that did not require the use of emotion words. Our findings support the hypothesis that discrete emotion concept knowledge helps transform perceptions of affect (positively or negatively valenced facial expressions) into perceptions of discrete emotions such as anger, disgust, fear, and sadness. These findings have important consequences for understanding the processes supporting emotion perception.

  11. Semantic Blogging : Spreading the Semantic Web Meme

    OpenAIRE

    Cayzer, Steve

    2004-01-01

    This paper is about semantic blogging, an application of the semantic web to blogging. The semantic web promises to make the web more useful by endowing metadata with machine processable semantics. Blogging is a lightweight web publishing paradigm which provides a very low barrier to entry, useful syndication and aggregation behaviour, a simple to understand structure and decentralized construction of a rich information network. Semantic blogging builds upon the success and clear network valu...

  12. Biomedical semantics in the Semantic Web.

    Science.gov (United States)

    Splendiani, Andrea; Burger, Albert; Paschke, Adrian; Romano, Paolo; Marshall, M Scott

    2011-03-07

    The Semantic Web offers an ideal platform for representing and linking biomedical information, which is a prerequisite for the development and application of analytical tools to address problems in data-intensive areas such as systems biology and translational medicine. As for any new paradigm, the adoption of the Semantic Web offers opportunities and poses questions and challenges to the life sciences scientific community: which technologies in the Semantic Web stack will be more beneficial for the life sciences? Is biomedical information too complex to benefit from simple interlinked representations? What are the implications of adopting a new paradigm for knowledge representation? What are the incentives for the adoption of the Semantic Web, and who are the facilitators? Is there going to be a Semantic Web revolution in the life sciences?We report here a few reflections on these questions, following discussions at the SWAT4LS (Semantic Web Applications and Tools for Life Sciences) workshop series, of which this Journal of Biomedical Semantics special issue presents selected papers from the 2009 edition, held in Amsterdam on November 20th.

  13. On the Existence of Semantic Working Memory: Evidence for Direct Semantic Maintenance

    Science.gov (United States)

    Shivde, Geeta; Anderson, Michael C.

    2011-01-01

    Despite widespread acknowledgment of the importance of online semantic maintenance, there has been astonishingly little work that clearly establishes this construct. We review the extant work relevant to short-term retention of meaning and show that, although consistent with semantic working memory, most data can be accommodated in other ways.…

  14. Cross-cultural adaptation of the Social and Emotional Questionnaire on Dementia for the Brazilian population

    Directory of Open Access Journals (Sweden)

    Tatiana Belfort

    Full Text Available ABSTRACTCONTEXT AND OBJECTIVE: Impairments in social and emotional functioning may affect the communication skills and interpersonal relationships of people with dementia and their caregivers. This study had the aim of presenting the steps involved in the cross-cultural adaptation of the Social and Emotional Questionnaire (SEQ for the Brazilian population.DESIGN AND SETTING: Cross-cultural adaptation study, conducted at the Center for Alzheimer's Disease and Related Disorders in a public university.METHODS: The process adopted in this study required six consecutive steps: initial translation, translation synthesis, back translation, committee of judges, pretesting of final version and submission to the original author.RESULTS: In general, the items had semantic, idiomatic, conceptual and experiential equivalence. During the first pretest, people with dementia and their caregivers had difficulties in understanding some items relating to social skills, which were interpreted ambiguously. New changes were made to allow better adjustment to the target population and, following this, a new pretest was performed. This pre-test showed that the changes were relevant and gave rise to the final version of the instrument. There was no correlation between education level and performance in the questionnaire, among people with dementia (P = 0.951.CONCLUSION: The Brazilian Portuguese version of the Social and Emotional Questionnaire was well understood and, despite the cultural and linguistic differences, the constructs of the original version were maintained.

  15. Direct Exploration of the Role of the Ventral Anterior Temporal Lobe in Semantic Memory: Cortical Stimulation and Local Field Potential Evidence From Subdural Grid Electrodes.

    Science.gov (United States)

    Shimotake, Akihiro; Matsumoto, Riki; Ueno, Taiji; Kunieda, Takeharu; Saito, Satoru; Hoffman, Paul; Kikuchi, Takayuki; Fukuyama, Hidenao; Miyamoto, Susumu; Takahashi, Ryosuke; Ikeda, Akio; Lambon Ralph, Matthew A

    2015-10-01

    Semantic memory is a crucial higher cortical function that codes the meaning of objects and words, and when impaired after neurological damage, patients are left with significant disability. Investigations of semantic dementia have implicated the anterior temporal lobe (ATL) region, in general, as crucial for multimodal semantic memory. The potentially crucial role of the ventral ATL subregion has been emphasized by recent functional neuroimaging studies, but the necessity of this precise area has not been selectively tested. The implantation of subdural electrode grids over this subregion, for the presurgical assessment of patients with partial epilepsy or brain tumor, offers the dual yet rare opportunities to record cortical local field potentials while participants complete semantic tasks and to stimulate the functionally identified regions in the same participants to evaluate the necessity of these areas in semantic processing. Across 6 patients, and utilizing a variety of semantic assessments, we evaluated and confirmed that the anterior fusiform/inferior temporal gyrus is crucial in multimodal, receptive, and expressive, semantic processing. © The Author 2014. Published by Oxford University Press.

  16. [False recognition of faces associated with fronto-temporal dementia with prosopagnosia].

    Science.gov (United States)

    Verstichel, P

    2005-09-01

    The association of prosopagnosia and false recognition of faces is unusual and contributes to our understanding of the generation of facial familiarity. A 67-year-old man with a left prefrontal traumatic lesion, developed a temporal variety of fronto-temporal dementia (semantic dementia) with amyotrophic lateral sclerosis. Cerebral imagery demonstrated a bilateral, temporal anterior atrophy predominating in the right hemisphere. The main cognitive signs consisted in severe difficulties to recognize faces of familiar people (prosopagnosia), associated with systematic false recognition of unfamiliar people. Neuropsychological testing indicated that the prosopagnosia probably resulted from the association of an associative/mnemonic mechanism (inability to activate the Face Recognition Units (FRU) from the visual input) and a semantic mechanism (degradation of semantic/biographical information or deconnexion between FRU and this information). At the early stage of the disease, the patient could activate residual semantic information about individuals from their names, but after a 4-year course, he failed to do so. This worsening could be attributed to the extension of the degenerative lesions to the left temporal lobe. Familiar and unfamiliar faces triggered a marked feeling of knowing. False recognition concerned all the unfamiliar faces, and the patient claimed spontaneously that they corresponded to actors, but he could not provide any additional information about their specific identities. The coexistence of prosopagnosia and false recognition suggests the existence of different interconnected systems processing face recognition, one intended to identification of individuals, and the other producing the sense of familiarity. Dysfunctions at different stages of one or the other of these two processes could result in distortions in the feeling of knowing. From this case and others reported in literature, we propose to complete the classical model of face processing

  17. An Island of Stability: Art Images and Natural Scenes – but Not Natural Faces – Show Consistent Esthetic Response in Alzheimer’s-Related Dementia

    Science.gov (United States)

    Graham, Daniel J.; Stockinger, Simone; Leder, Helmut

    2013-01-01

    Alzheimer’s disease (AD) causes severe impairments in cognitive function but there is evidence that aspects of esthetic perception are somewhat spared, at least in early stages of the disease. People with early Alzheimer’s-related dementia have been found to show similar degrees of stability over time in esthetic judgment of paintings compared to controls, despite poor explicit memory for the images. Here we expand on this line of inquiry to investigate the types of perceptual judgments involved, and to test whether people in later stages of the disease also show evidence of preserved esthetic judgment. Our results confirm that, compared to healthy controls, there is similar esthetic stability in early stage AD in the absence of explicit memory, and we report here that people with later stages of the disease also show similar stability compared to controls. However, while we find that stability for portrait paintings, landscape paintings, and landscape photographs is not different compared to control group performance, stability for face photographs – which were matched for identity with the portrait paintings – was significantly impaired in the AD group. We suggest that partially spared face-processing systems interfere with esthetic processing of natural faces in ways that are not found for artistic images and landscape photographs. Thus, our work provides a novel form of evidence regarding face-processing in healthy and diseased aging. Our work also gives insights into general theories of esthetics, since people with AD are not encumbered by many of the semantic and emotional factors that otherwise color esthetic judgment. We conclude that, for people with AD, basic esthetic judgment of artistic images represents an “island of stability” in a condition that in most other respects causes profound cognitive disruption. As such, esthetic response could be a promising route to future therapies. PMID:23471005

  18. Neurocognitive differential diagnosis of dementing diseases: Alzheimer's Dementia, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder.

    Science.gov (United States)

    Braaten, Alyssa J; Parsons, Thomas D; McCue, Robert; Sellers, Alfred; Burns, William J

    2006-11-01

    Similarities in presentation of Dementia of Alzheimer's Type, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder, pose differential diagnosis challenges. The current study identifies specific neuropsychological patterns of scores for Dementia of Alzheimer's Type, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder. Neuropsychological domains directly assessed in the study included: immediate memory, delayed memory, confrontational naming, verbal fluency, attention, concentration, and executive functioning. The results reveal specific neuropsychological comparative profiles for Dementia of Alzheimer's Type, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder. The identification of these profiles will assist in the differential diagnosis of these disorders and aid in patient treatment.

  19. Suicide and assisted dying in dementia: what we know and what we need to know. A narrative literature review.

    Science.gov (United States)

    Diehl-Schmid, J; Jox, R; Gauthier, S; Belleville, S; Racine, E; Schüle, C; Turecki, G; Richard-Devantoy, S

    2017-08-01

    Evidence-based data on prevalence and risk factors of suicidal intentions and behavior in dementia are as scarce as the data on assisted dying. The present literature review aimed on summarizing the current knowledge and provides a critical discussion of the results. A systematic narrative literature review was performed using Medline, Cochrane Library, EMBASE, PSYNDEX, PSYCINFO, Sowiport, and Social Sciences Citation Index literature. Dementia as a whole does not appear to be a risk factor for suicide completion. Nonetheless some subgroups of patients with dementia apparently have an increased risk for suicidal behavior, such as patients with psychiatric comorbidities (particularly depression) and of younger age. Furthermore, a recent diagnosis of dementia, semantic dementia, and previous suicide attempts most probably elevate the risk for suicidal intentions and behavior. The impact of other potential risk factors, such as patient's cognitive impairment profile, behavioral disturbances, social isolation, or a biomarker based presymptomatic diagnosis has not yet been investigated. Assisted dying in dementia is rare but numbers seem to increase in regions where it is legally permitted. Most studies that had investigated the prevalence and risk factors for suicide in dementia had significant methodological limitations. Large prospective studies need to be conducted in order to evaluate risk factors for suicide and assisted suicide in patients with dementia and persons with very early or presymptomatic diagnoses of dementia. In clinical practice, known risk factors for suicide should be assessed in a standardized way so that appropriate action can be taken when necessary.

  20. Semantics-based Automated Web Testing

    Directory of Open Access Journals (Sweden)

    Hai-Feng Guo

    2015-08-01

    Full Text Available We present TAO, a software testing tool performing automated test and oracle generation based on a semantic approach. TAO entangles grammar-based test generation with automated semantics evaluation using a denotational semantics framework. We show how TAO can be incorporated with the Selenium automation tool for automated web testing, and how TAO can be further extended to support automated delta debugging, where a failing web test script can be systematically reduced based on grammar-directed strategies. A real-life parking website is adopted throughout the paper to demonstrate the effectivity of our semantics-based web testing approach.

  1. Verbal creativity in semantic variant primary progressive aphasia.

    Science.gov (United States)

    Wu, Teresa Q; Miller, Zachary A; Adhimoolam, Babu; Zackey, Diana D; Khan, Baber K; Ketelle, Robin; Rankin, Katherine P; Miller, Bruce L

    2015-02-01

    Emergence of visual and musical creativity in the setting of neurologic disease has been reported in patients with semantic variant primary progressive aphasia (svPPA), also called semantic dementia (SD). It is hypothesized that loss of left anterior frontotemporal function facilitates activity of the right posterior hemispheric structures, leading to de novo creativity observed in visual artistic representation. We describe creativity in the verbal domain, for the first time, in three patients with svPPA. Clinical presentations are carefully described in three svPPA patients exhibiting verbal creativity, including neuropsychology, neurologic exam, and structural magnetic resonance imaging (MRI). Voxel-based morphometry (VBM) was performed to quantify brain atrophy patterns in these patients against age-matched healthy controls. All three patients displayed new-onset creative writing behavior and produced extensive original work during the course of disease. Patient A developed interest in wordplay and generated a large volume of poetry. Patient B became fascinated with rhyming and punning. Patient C wrote and published a lifestyle guidebook. An overlap of their structural MR scans showed uniform sparing in the lateral portions of the language-dominant temporal lobe (superior and middle gyri) and atrophy in the medial temporal cortex (amygdala, limbic cortex). New-onset creativity in svPPA may represent a paradoxical functional facilitation. A similar drive for production is found in visually artistic and verbally creative patients. Mirroring the imaging findings in visually artistic patients, verbal preoccupation and creativity may be associated with medial atrophy in the language-dominant temporal lobe, but sparing of lateral dominant temporal and non-dominant posterior cortices.

  2. Pharmacotherapy of dementia

    Directory of Open Access Journals (Sweden)

    Ajit Avasthi

    2016-01-01

    Full Text Available This review aims to evaluate the existing evidence for pharmacotherapy for management of dementia. Data search strategies included electronic databases of relevant publications or cross-references. The searches were limited to acetyl cholinesterase inhibitors (AChEIs, memantine, antipsychotics, antidepressants, mood stabilizers, and benzodiazepines. Data in the form of meta-analysis and systemic reviews for treatment in five main types of dementia (Alzheimer′s, frontotemporal, Parkinson′s, Lewy body disease, and vascular type were extracted. If a meta-analysis or systemic review was not available, then the searches included evaluation of data in the form of double-blind, randomized controlled trials or open-label studies. Various studies suggest that compared to placebo, AChEIs and memantine are associated with better outcome in all domains of Alzheimer′s disease. In addition, combination therapy of AChEIs and memantine is superior to monotherapy with AChEIs in terms of behavioral disturbances, activities of daily living, and global assessment. In patients with dementia associated with Parkinson′s disease or Lewy body dementia, use of donepezil, rivastigmine, and memantine is associated with significant efficacy on the global outcome measures when compared with placebo. Compared to placebo, AChEIs, but not memantine, have also been shown to have better cognitive outcomes in patients with dementia associated with Parkinson′s disease or Lewy body dementia. Data are limited for the role of pharmacotherapy in management of frontotemporal dementia. In patients of vascular dementia, all AChEIs and memantine show some beneficial effects on cognition. Antidepressants and antipsychotics have been shown to be beneficial in management of behavioral symptoms and agitation. However, it is important to remember that there is black box warning for use of antipsychotics among patients with dementia. One of the major limitations of the research is

  3. Semantic Advertising

    OpenAIRE

    Zamanzadeh, Ben; Ashish, Naveen; Ramakrishnan, Cartic; Zimmerman, John

    2013-01-01

    We present the concept of Semantic Advertising which we see as the future of online advertising. Semantic Advertising is online advertising powered by semantic technology which essentially enables us to represent and reason with concepts and the meaning of things. This paper aims to 1) Define semantic advertising, 2) Place it in the context of broader and more widely used concepts such as the Semantic Web and Semantic Search, 3) Provide a survey of work in related areas such as context matchi...

  4. Semantics, contrastive linguistics and parallel corpora

    Directory of Open Access Journals (Sweden)

    Violetta Koseska

    2014-09-01

    Full Text Available Semantics, contrastive linguistics and parallel corpora In view of the ambiguity of the term “semantics”, the author shows the differences between the traditional lexical semantics and the contemporary semantics in the light of various semantic schools. She examines semantics differently in connection with contrastive studies where the description must necessary go from the meaning towards the linguistic form, whereas in traditional contrastive studies the description proceeded from the form towards the meaning. This requirement regarding theoretical contrastive studies necessitates construction of a semantic interlanguage, rather than only singling out universal semantic categories expressed with various language means. Such studies can be strongly supported by parallel corpora. However, in order to make them useful for linguists in manual and computer translations, as well as in the development of dictionaries, including online ones, we need not only formal, often automatic, annotation of texts, but also semantic annotation - which is unfortunately manual. In the article we focus on semantic annotation concerning time, aspect and quantification of names and predicates in the whole semantic structure of the sentence on the example of the “Polish-Bulgarian-Russian parallel corpus”.

  5. Association between Frailty and Dementia

    DEFF Research Database (Denmark)

    Kulmala, J; Nykänen, I; Mänty, Minna Regina

    2014-01-01

    dementia with Lewy bodies and 8 persons (1%) had some other type of dementia. Multivariate logistic regression models showed that frail persons were almost 8 times more likely to have cognitive impairment (OR 7.8, 95% CI 4.0-15.0), 8 times more likely to have some kind of dementia (OR 8.0, 95% CI 4.0...... of the participants was assessed using the Cardiovascular Health Study criteria. Cognitive function was assessed with the Mini-Mental State Examination (MMSE). Clinically diagnosed dementia was assessed by specialists using diagnostic criteria. The associations between frailty and cognition were investigated using...

  6. Association between recognizing dementia as a mental illness and dementia knowledge among elderly Chinese Americans.

    Science.gov (United States)

    Zheng, Xin; Woo, Benjamin K P

    2016-06-22

    To investigate whether older Chinese Americans perceive dementia as a mental illness and the relationship between such perception and their general understanding of dementia remains unclear. Our study aims to understand this relationship and its future implication on improving dementia literacy among ethnic minorities. Elderly Chinese American participants from the Greater Los Angeles were asked to complete an 11-item dementia questionnaire, following a community health seminar. Cross-sectional survey data was analyzed using standard statistical methods. The questionnaire received an 88.3% response rate. Among 316 responders, only 28.8% (n = 91) of elderly Chinese Americans identified dementia as a mental illness, and 71.2% (n = 225) did not recognize its mental disease origin. Furthermore, in comparison between these two groups, the first group demonstrated significantly higher level of baseline knowledge of the disease. This study reveals that only approximately 1 out of 4 older Chinese Americans recognized dementia as a mental illness, consistent with previous studies on Asian Americans. Our study however showed that when dementia was being perceived as a mental illness, such perception was associated with a higher level of baseline dementia understanding. The current study suggested the potential of improving older Chinese Americans dementia literacy by increasing awareness of its mental illness origin.

  7. First TV ad for dementia care.

    Science.gov (United States)

    2008-12-10

    Last month, viewers saw the first-ever TV advertisement about providing care for people with dementia. Screened as part of Bupa's initiative, bringing the issue of dementia care 'out of the shadows,' the ad features Ernie visiting his sister June, who has dementia, in a Bupa care home and shows the personalised care being delivered by specially trained staff.

  8. Semantator: annotating clinical narratives with semantic web ontologies.

    Science.gov (United States)

    Song, Dezhao; Chute, Christopher G; Tao, Cui

    2012-01-01

    To facilitate clinical research, clinical data needs to be stored in a machine processable and understandable way. Manual annotating clinical data is time consuming. Automatic approaches (e.g., Natural Language Processing systems) have been adopted to convert such data into structured formats; however, the quality of such automatically extracted data may not always be satisfying. In this paper, we propose Semantator, a semi-automatic tool for document annotation with Semantic Web ontologies. With a loaded free text document and an ontology, Semantator supports the creation/deletion of ontology instances for any document fragment, linking/disconnecting instances with the properties in the ontology, and also enables automatic annotation by connecting to the NCBO annotator and cTAKES. By representing annotations in Semantic Web standards, Semantator supports reasoning based upon the underlying semantics of the owl:disjointWith and owl:equivalentClass predicates. We present discussions based on user experiences of using Semantator.

  9. Computertomographic studies of dementia

    International Nuclear Information System (INIS)

    Kohlmeyer, K.

    1983-01-01

    It seems to be very complicated even for the experienced neurologist and psychiatrist to correlate the clinical syndrome of dementia to different causing cerebral processes such as a primarily degenerative brain atrophy, a chronic cerebrovascular insufficiency, or other rarer occurring brain diseases unless neurological signs and symptoms do indicate a focal brain lesion. Since computed tomography is able to show both focal and general changes of the brain tissue each patient presenting with a dementia clinically should be undergone such a neuroradiological investigation at least once, and if being negative even repeatedly. Computed tomography is able not only to detect unexpected treatable brain lesions as a cause of dementia for instance tumors, subdural hematomas, and communicating hydrocephalus to expect in about 6% of cases with the clinical diagnosis of dementia, but also it is able to help to make the differentialdiagnosis of the dementia of Alzheimer's and the multi-infarct-type in a high percentage. Nevertheless despite the use of computed tomography the pathogenesis of dementia even though being undoubtful clinically remains obscure in 15% of our material of 367 demented patients studied by computed tomography but presenting with a normal finding. (orig.) [de

  10. A Denotational Semantics for Logic Programming

    DEFF Research Database (Denmark)

    Frandsen, Gudmund Skovbjerg

    A fully abstract denotational semantics for logic programming has not been constructed yet. In this paper we present a denotational semantics that is almost fully abstract. We take the meaning of a logic program to be an element in a Plotkin power domain of substitutions. In this way our result...... shows that standard domain constructions suffice, when giving a semantics for logic programming. Using the well-known fixpoint semantics of logic programming we have to consider two different fixpoints in order to obtain information about both successful and failed computations. In contrast, our...... semantics is uniform in that the (single) meaning of a logic program contains information about both successful, failed and infinite computations. Finally, based on the full abstractness result, we argue that the detail level of substitutions is needed in any denotational semantics for logic programming....

  11. Lewy Body Dementia

    Science.gov (United States)

    Lewy body dementia Overview Lewy body dementia, also known as dementia with Lewy bodies, is the second most common type of progressive dementia after Alzheimer's disease dementia. Protein deposits, ...

  12. Semantic content-based recommendations using semantic graphs.

    Science.gov (United States)

    Guo, Weisen; Kraines, Steven B

    2010-01-01

    Recommender systems (RSs) can be useful for suggesting items that might be of interest to specific users. Most existing content-based recommendation (CBR) systems are designed to recommend items based on text content, and the items in these systems are usually described with keywords. However, similarity evaluations based on keywords suffer from the ambiguity of natural languages. We present a semantic CBR method that uses Semantic Web technologies to recommend items that are more similar semantically with the items that the user prefers. We use semantic graphs to represent the items and we calculate the similarity scores for each pair of semantic graphs using an inverse graph frequency algorithm. The items having higher similarity scores to the items that are known to be preferred by the user are recommended.

  13. Occult CSF flow disturbance of patients with Alzheimer type dementia and vascular dementia; Results from Iotrolan CT-cisternography

    Energy Technology Data Exchange (ETDEWEB)

    Kono, Kazuhiko; Sugita, Yasuko; Funaki, Chiaki [Nagoya Univ. (Japan). Faculty of Medicine; and others

    1994-04-01

    We report results of Iotrolan CT-cisternography on 41 demented patients (13 males and 28 females) to find 'occult normal pressure hydrocephalus'. These patients were suspected to have CSF flow disturbance from clinical symptoms and simple brain CT scan findings. Their average age, duration of dementia, and score of Hasegawa's dementia scale (HDS) were 76.2 years, 5.9 years, 9.5/32.5,respectively. Before performing CT-cisternography, clinical diagnosis for their dementia were vascular dementia in 18 patients. Alzheimer type dementia in 12, suspect of NPH in 5, and other diagnoses in 6. From the results of cisternography, we found 13 patients with CSF flow disturbance (contrast material remained in the ventricle more than 48 hours after injection), and 17 patients with normal CSF flow. The former showed lower scores of HDS, higher urinary incontinence scores and smaller areas of the interhemispheric fissure on CT scan than the latter. But the former showed no significant difference from the latter in the average age, duration of dementia and width of the ventricles. (author).

  14. Forecasting the Incidence of Dementia and Dementia-Related Outpatient Visits With Google Trends: Evidence From Taiwan.

    Science.gov (United States)

    Wang, Ho-Wei; Chen, Duan-Rung; Yu, Hsiao-Wei; Chen, Ya-Mei

    2015-11-19

    Google Trends has demonstrated the capability to both monitor and predict epidemic outbreaks. The connection between Internet searches for dementia information and dementia incidence and dementia-related outpatient visits remains unknown. This study aimed to determine whether Google Trends could provide insight into trends in dementia incidence and related outpatient visits in Taiwan. We investigated and validated the local search terms that would be the best predictors of new dementia cases and outpatient visits. We further evaluated the nowcasting (ie, forecasting the present) and forecasting effects of Google Trends search trends for new dementia cases and outpatient visits. The long-term goal is to develop a surveillance system to help early detection and interventions for dementia in Taiwan. This study collected (1) dementia data from Taiwan's National Health Insurance Research Database and (2) local Internet search data from Google Trends, both from January 2009 to December 2011. We investigated and validated search terms that would be the best predictors of new dementia cases and outpatient visits. We then evaluated both the nowcasting and the forecasting effects of Google Trends search trends through cross-correlation analysis of the dementia incidence and outpatient visit data with the Google Trends data. The search term "dementia + Alzheimer's disease" demonstrated a 3-month lead effect for new dementia cases and a 6-month lead effect for outpatient visits (r=.503, P=.002; r=.431, P=.009, respectively). When gender was included in the analysis, the search term "dementia" showed 6-month predictive power for new female dementia cases (r=.520, P=.001), but only a nowcasting effect for male cases (r=.430, P=.009). The search term "neurology" demonstrated a 3-month leading effect for new dementia cases (r=.433, P=.008), for new male dementia cases (r=.434, P=.008), and for outpatient visits (r=.613, Pdata may allow the health care system in Taiwan to prepare

  15. [Dementia due to Endocrine Diseases].

    Science.gov (United States)

    Matsunaga, Akiko; Yoneda, Makoto

    2016-04-01

    Endocrine diseases affecting various organs, such as the pituitary gland, the thyroid, the parathyroid, the adrenal glands and the pancreas, occasionally cause dementia. While Alzheimer's disease (AD) is the main cause of dementia in the elderly and is untreatable, dementia caused by endocrine diseases is treatable in most cases. However, patients with dementia associated with endocrine diseases show memory impairments similar to those found in AD, often leading to misdiagnoses. Patients with endocrine diseases often present with other characteristic systemic and neuropsychiatric symptoms caused by altered hormone levels. Such neuropsychiatric symptoms include involuntary movements, depression, seizures, and muscle weakness. In these cases, abnormalities in imaging and blood or urine tests are helpful in making a differential diagnosis. As delays in the diagnosis and treatment of these patients may cause irreversible brain damage, it is imperative for clinicians to carefully exclude the possibility of latent endocrine diseases when treating patients with dementia.

  16. Behavioral and language variants of frontotemporal dementia: a review of key symptoms.

    Science.gov (United States)

    Laforce, Robert

    2013-12-01

    While recent advances in the development of neuroimaging and molecular biomarkers for studying neurodegenerative conditions have revolutionized the field, dementia remains a clinical diagnosis. No component of the diagnostic process is more crucial than obtaining a good history. Getting to know the first manifestations of the disease, tracking their evolution and functional impact, combined with a targeted neurological examination, further guides differential diagnosis. This paper summarizes the key symptoms of the behavioral and language variants of frontotemporal dementia. The behavioral variant of frontotemporal dementia (bvFTD) is characterized by severe changes in behavior and personality such as disinhibition, apathy, loss of empathy, or stereotypic behavior, leading to a loss of social competence. Executive functions are impaired, while memory and visuospatial skills are relatively better preserved. By contrast, the language variants or primary progressive aphasias (PPAs) are marked by prominent language disturbances that can be subclassified into a non-fluent/agrammatic variant (naPPA), a semantic variant (svPPA), and a logopenic variant (lvPPA). Although combined characterization of clinical, imaging, biological and genetic biomarkers is essential to establish a detailed diagnosis of such heterogeneous conditions, the author emphasizes the importance of accurate recognition of key symptoms that can lead to better identification of underlying neuropathology and appropriate treatment approaches.

  17. Semantic Coherence Facilitates Distributional Learning.

    Science.gov (United States)

    Ouyang, Long; Boroditsky, Lera; Frank, Michael C

    2017-04-01

    Computational models have shown that purely statistical knowledge about words' linguistic contexts is sufficient to learn many properties of words, including syntactic and semantic category. For example, models can infer that "postman" and "mailman" are semantically similar because they have quantitatively similar patterns of association with other words (e.g., they both tend to occur with words like "deliver," "truck," "package"). In contrast to these computational results, artificial language learning experiments suggest that distributional statistics alone do not facilitate learning of linguistic categories. However, experiments in this paradigm expose participants to entirely novel words, whereas real language learners encounter input that contains some known words that are semantically organized. In three experiments, we show that (a) the presence of familiar semantic reference points facilitates distributional learning and (b) this effect crucially depends both on the presence of known words and the adherence of these known words to some semantic organization. Copyright © 2016 Cognitive Science Society, Inc.

  18. Fast Distributed Dynamics of Semantic Networks via Social Media

    Directory of Open Access Journals (Sweden)

    Facundo Carrillo

    2015-01-01

    Full Text Available We investigate the dynamics of semantic organization using social media, a collective expression of human thought. We propose a novel, time-dependent semantic similarity measure (TSS, based on the social network Twitter. We show that TSS is consistent with static measures of similarity but provides high temporal resolution for the identification of real-world events and induced changes in the distributed structure of semantic relationships across the entire lexicon. Using TSS, we measured the evolution of a concept and its movement along the semantic neighborhood, driven by specific news/events. Finally, we showed that particular events may trigger a temporary reorganization of elements in the semantic network.

  19. Rights in mind: Thinking differently about dementia and disability.

    Science.gov (United States)

    Shakespeare, Tom; Zeilig, Hannah; Mittler, Peter

    2017-01-01

    The aim of this paper is to argue for the utility of a relational model of disability, as a way of conceptualizing dementia. We explore whether dementia should be considered as a disability, and whether people with dementia might consider themselves as disabled people. We review examples of, and issues raised by, the political activism of people with dementia. We consider how language constructs dementia negatively. We discuss how the environment influences the experience of dementia. In conclusion, we show that a relational model of dementia lays the basis for a human rights approach to the condition, based on collaborative partnerships between people with dementia and people from other disability communities.

  20. Pick disease

    Science.gov (United States)

    Semantic dementia; Dementia - semantic; Frontotemporal dementia; FTD; Arnold Pick disease; 3R tauopathy ... doctors tell Pick disease apart from Alzheimer disease. (Memory loss is often the main, and earliest, symptom ...

  1. Lewy body dementias

    DEFF Research Database (Denmark)

    Løkkegaard, Annemette; Korbo, Lise

    2017-01-01

    Dementia with Lewy bodies and Parkinson disease dementia share the same pathophysiology. Together they are called Lewy body dementias and are the second most common type of dementia. Lewy body dementias receive little attention, and patients are often misdiagnosed, leading to less than ideal...

  2. Information Interaction as a Mechanism of Semantic Gap Elimination

    Directory of Open Access Journals (Sweden)

    Victor Y. Tsvetkov

    2013-01-01

    Full Text Available The article studies semantic gap as an objective phenomenon, shows that semantic gap occurs both in parallel computing and in other areas. Semantic description of the content is revealed as a set of different descriptions. Causes of semantic gap are described. The content of information exchange is explained in the article. Information interaction in the semantic field is interpreted as a mechanism to lessen the gap

  3. Dementia and the gender trouble?: Theorising dementia, gendered subjectivity and embodiment.

    Science.gov (United States)

    Sandberg, Linn J

    2018-06-01

    Despite person-centred approaches increasingly focusing on looking at the person in dementia instead of the pathology, the role of gender in dementia has been little explored. This article discusses how pervasive discourses on a loss of self and dementia as abject are interwoven with a de-gendering of persons with dementia. The cultural anxiety that dementia evokes in terms of loss of bodily and cognitive control could also be linked to a failure to normatively and intelligibly express gender when living with dementia. As a way to sustain personhood for people with dementia and challenge discourses on people with dementia as 'non-people', person-centred approaches have emphasised the collaborative work of carers, relatives and persons with dementia. Often implicitly, this also involves a 're-gendering' of persons with dementia where gendered biographies and pasts are upheld and gendered embodied selfhood is maintained through, for example, dress, hair and other aspects of appearance. This re-gendering could be of great significance for people with dementia to become intelligible as persons. Still, dementia studies must further consider non-normative expressions of gender and involve feminist theorising on gender as a power asymmetry since some embodiments and selves are more likely to be sustained in dementia than others. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. The pathological basis of dementia in the aged and reliability of computed tomograms in the diagnosis of dementia

    International Nuclear Information System (INIS)

    Tohgi, Hideo

    1981-01-01

    Pathological findings of demented (89 cases) and non-demented, control subjects (74 cases) in the aged were compared. The reliability of CT in the diagnosis was also studied. 1) Brain weight and the degree of ventricular dilatation were related to dementia, but the degree of convolutional atrophy showed no correlation with dementia. 2) Among various types of cerebrovascular lesions, only diffuse white matter lesions can be the cause of dementia. 3) Cases with dementia were classified into 4 groups as regards to which of cerebrovascular lesions and senile plaques was more prominent histologically. 4) CT evaluations coincided with pathological findings in only 17.9% in the degree of ventricular dilatation and 57.1% in the degree of convolutional atrophy. Ninty-three percent of cases without periventricular lucency did not show diffuse white matter lesions at autopsy, while only 50% of cases with periventricular lucency were confirmed to have diffuse white matter lesions. 5) The degree of ventricular dilatation, conventional atrophy, periventricular lucency, and subarachnoid free space in the cerebral convexity were studied in relation to dementia. The sum of the evaluations of these indices had a significant correlation with dementia. (J.P.N.)

  5. Geospatial semantic web

    CERN Document Server

    Zhang, Chuanrong; Li, Weidong

    2015-01-01

    This book covers key issues related to Geospatial Semantic Web, including geospatial web services for spatial data interoperability; geospatial ontology for semantic interoperability; ontology creation, sharing, and integration; querying knowledge and information from heterogeneous data source; interfaces for Geospatial Semantic Web, VGI (Volunteered Geographic Information) and Geospatial Semantic Web; challenges of Geospatial Semantic Web; and development of Geospatial Semantic Web applications. This book also describes state-of-the-art technologies that attempt to solve these problems such as WFS, WMS, RDF, OWL, and GeoSPARQL, and demonstrates how to use the Geospatial Semantic Web technologies to solve practical real-world problems such as spatial data interoperability.

  6. Language networks associated with computerized semantic indices.

    Science.gov (United States)

    Pakhomov, Serguei V S; Jones, David T; Knopman, David S

    2015-01-01

    Tests of generative semantic verbal fluency are widely used to study organization and representation of concepts in the human brain. Previous studies demonstrated that clustering and switching behavior during verbal fluency tasks is supported by multiple brain mechanisms associated with semantic memory and executive control. Previous work relied on manual assessments of semantic relatedness between words and grouping of words into semantic clusters. We investigated a computational linguistic approach to measuring the strength of semantic relatedness between words based on latent semantic analysis of word co-occurrences in a subset of a large online encyclopedia. We computed semantic clustering indices and compared them to brain network connectivity measures obtained with task-free fMRI in a sample consisting of healthy participants and those differentially affected by cognitive impairment. We found that semantic clustering indices were associated with brain network connectivity in distinct areas including fronto-temporal, fronto-parietal and fusiform gyrus regions. This study shows that computerized semantic indices complement traditional assessments of verbal fluency to provide a more complete account of the relationship between brain and verbal behavior involved organization and retrieval of lexical information from memory. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Prevalence of Pain in Nursing Home Residents: The Role of Dementia Stage and Dementia Subtypes.

    Science.gov (United States)

    van Kooten, Janine; Smalbrugge, Martin; van der Wouden, Johannes C; Stek, Max L; Hertogh, Cees M P M

    2017-06-01

    To study pain prevalence, pain type, and its pharmacological treatment in Dutch nursing home residents in relation to dementia subtype and dementia severity. Data were collected as part of the PAINdemiA study, an observational cross-sectional study conducted between May 2014 and December 2015. Ten nursing homes in the Netherlands. A total of 199 nursing home residents in various stages of dementia. We collected data on pain (by observation: MOBID-2 Pain Scale and by self-report scales), pain type, pain medication, dementia subtype, dementia severity (GDS), and demographic features. In the whole sample, the prevalence of pain was 43% (95% confidence interval 36%-50%) using the MOBID-2 Pain Scale. Regardless of regularly scheduled analgesics, approximately one-third of the residents with pain suffered from moderate to severe pain. Pain assessment with the MOBID-2 Pain Scale showed no difference in pain between dementia subtypes, but residents with more severe dementia experienced pain more often than those with less severe dementia (27% vs 15%). The prevalence of self-reported pain was significantly higher in residents with vascular dementia (VaD) (54%) compared with those with Alzheimer disease (18%) and other dementia subtypes (14%). Nociceptive pain was the predominant type of pain (72%) followed by mixed pain (25%). Acetaminophen was the most prescribed analgesic (80%). Most of the participating nursing home residents had no pain; however, pain was observed more often in residents with severe dementia, whereas residents in the early stages of VaD self-reported pain more often that those with other dementia subtypes. As one-third of the residents with clinically relevant pain had moderate to severe pain regardless of using pain medication, more focus should be on how pain management could use more tailored approaches and be regularly adjusted to individual needs. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by

  8. Semantic representations in the temporal pole predict false memories.

    Science.gov (United States)

    Chadwick, Martin J; Anjum, Raeesa S; Kumaran, Dharshan; Schacter, Daniel L; Spiers, Hugo J; Hassabis, Demis

    2016-09-06

    Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the "semantic hub" of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories.

  9. Semantic representations in the temporal pole predict false memories

    Science.gov (United States)

    Chadwick, Martin J.; Anjum, Raeesa S.; Kumaran, Dharshan; Schacter, Daniel L.; Spiers, Hugo J.; Hassabis, Demis

    2016-01-01

    Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the “semantic hub” of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories. PMID:27551087

  10. Semantic Multimedia

    NARCIS (Netherlands)

    S. Staab; A. Scherp; R. Arndt; R. Troncy (Raphael); M. Grzegorzek; C. Saathoff; S. Schenk; L. Hardman (Lynda)

    2008-01-01

    htmlabstractMultimedia constitutes an interesting field of application for Semantic Web and Semantic Web reasoning, as the access and management of multimedia content and context depends strongly on the semantic descriptions of both. At the same time, multimedia resources constitute complex objects,

  11. Dancing as an Intervention Tool for People with Dementia: A Mini-Review Dancing and Dementia.

    Science.gov (United States)

    Klimova, Blanka; Valis, Martin; Kuca, Kamil

    2017-01-01

    Research studies show a positive impact of physical activities such as dancing on the improvement of cognitive reserves of people with dementia. The purpose of this study is to explore dancing efficacy on people with dementia and list the key benefits and limitations of dancing therapy for these people. The methods used in this study include a method of literature review of available Englishwritten sources with respect to the dancing therapy and dementia in the acknowledged databases Pub- Med, Web of Science, Springer, and Scopus, and a method of comparison and evaluation of their findings. The findings of this mini review confirm positive efficacy of dancing therapy on cognitive, physical, emotional and social performance of people with dementia. More randomized controlled clinical trials should be conducted in this field, as well as other non-pharmacological therapies should be employed in order to holistically contribute to the prevention and treatment of dementia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Semantic interpretation of search engine resultant

    Science.gov (United States)

    Nasution, M. K. M.

    2018-01-01

    In semantic, logical language can be interpreted in various forms, but the certainty of meaning is included in the uncertainty, which directly always influences the role of technology. One results of this uncertainty applies to search engines as user interfaces with information spaces such as the Web. Therefore, the behaviour of search engine results should be interpreted with certainty through semantic formulation as interpretation. Behaviour formulation shows there are various interpretations that can be done semantically either temporary, inclusion, or repeat.

  13. Clinical and Neuropsychological Characteristics of a Nationwide Hospital-Based Registry of Frontotemporal Dementia Patients in Korea: A CREDOS-FTD Study

    Directory of Open Access Journals (Sweden)

    Eun-Joo Kim

    2014-07-01

    Full Text Available Background: We investigated the demographic, clinical, and neuropsychological characteristics of frontotemporal dementia (FTD from the Clinical Research Center for Dementia of South Korea (CREDOS-FTD registry. Methods: A total of 200 consecutive patients with FTD recruited from 16 neurological clinics in Korea were evaluated by cognitive and functional assessments, a screening test for aphasia, behavioral questionnaires, motor assessments, and brain MRI or PET. Results: In our registry, 78 patients were classified as having been diagnosed with behavioral-variant FTD (bvFTD, 70 with semantic dementia (SD, 33 with progressive nonfluent aphasia (PNFA, and 8 with motor neuron disease plus syndrome (MND-plus. The patients with language variants of dementia were older than those with bvFTD. There were no differences in sex ratio, duration of illness, or level of education among the four subgroups. Overall, the patients with bvFTD showed a significantly better performance in cognitive tests. A higher frequency of motor symptoms and a lower frequency of behavioral symptoms were found in PNFA than in bvFTD and SD. The Global Language Index was significantly lower in SD than in bvFTD and PNFA. The MND-plus group had a poorer performance than all the others in all cognitive domains. Conclusion: The neuropsychological, behavioral, motor, and language characteristics of the four subtypes are comparable with those from other series. However, the proportion of SD (37.0%, which was similar to that of bvFTD (41.3%, was higher in our registry than in other series.

  14. Types of Dementia

    Science.gov (United States)

    ... Kids For Teens For Parents & Teachers Resolving Family Conflicts The Holidays and Alzheimer's Glossary Virtual Library Online ... Use Map Selector Search Alzheimer’s Association Alzheimer's & Dementia Types of Dementia Types of Dementia Types of Dementia ...

  15. Validation of a new mass screening tool for cognitive impairment: Cognitive Assessment for Dementia, iPad version

    Directory of Open Access Journals (Sweden)

    Onoda K

    2013-03-01

    Full Text Available Keiichi Onoda,1 Tsuyoshi Hamano,2 Yoko Nabika,1 Atsuo Aoyama,1 Hiroyuki Takayoshi,1 Tomonori Nakagawa,1 Masaki Ishihara,1 Shingo Mitaki,1 Takuya Yamaguchi,1 Hiroaki Oguro,1 Kuninori Shiwaku,3 Shuhei Yamaguchi1 1Department of Neurology, 2Center for Community-Based Health Research and Education, Shimane University, Izumo, 3Shimane University, Matsue, Shimane, Japan Background: We have developed a new screening test for dementia that runs on an iPad and can be used for mass screening, known as the Cognitive Assessment for Dementia, iPad version (CADi. The CADi consists of items involving immediate recognition memory for three words, semantic memory, categorization of six objects, subtraction, backward repetition of digits, cube rotation, pyramid rotation, trail making A, trail making B, and delayed recognition memory for three words. The present study examined the reliability and validity of the CADi. Methods: CADi evaluations were conducted for patients with dementia, healthy subjects selected from a brain checkup system, and community-dwelling elderly people participating in health checkups. Results: CADi scores were lower for dementia patients than for healthy elderly individuals and correlated significantly with Mini-Mental State Examination scores. Cronbach’s alpha values for the CADi were acceptable (over 0.7, and test–retest reliability was confirmed via a significant correlation between scores separated by a one-year interval. Conclusion: These results suggest that the CADi is a useful tool for mass screening of dementia in Japanese populations. Keywords: dementia, mass screening, early detection, iPad

  16. Relaxation as a Factor in Semantic Desensitization

    Science.gov (United States)

    Bechtel, James E.; McNamara, J. Regis

    1975-01-01

    Relaxation and semantic desensitization were used to alleviate the fear of phobic females. Results showed that semantic desensitization, alone or in combination with relaxation, failed to modify the evaluative meanings evoked by the feared object. (SE)

  17. Measuring the expressed emotion in Chinese family caregivers of persons with dementia: Validation of a Chinese version of the Family Attitude Scale.

    Science.gov (United States)

    Yu, Doris S F; Kwok, Timothy; Choy, Jacky; Kavanagh, David J

    2016-03-01

    Expressed emotion (EE) captures the affective quality of the relationship between family caregivers and their care recipients and is known to increase the risk of poor health outcomes for caregiving dyads. Little is known about expressed emotion in the context of caregiving for persons with dementia, especially in non-Western cultures. The Family Attitude Scale (FAS) is a psychometrically sound self-reporting measure for EE. Its use in the examination of caregiving for patients with dementia has not yet been explored. This study was performed to examine the psychometric properties of the Chinese version of the FAS (FAS-C) in Chinese caregivers of relatives with dementia, and its validity in predicting severe depressive symptoms among the caregivers. The FAS was translated into Chinese using Brislin's model. Two expert panels evaluated the semantic equivalence and content validity of this Chinese version (FAS-C), respectively. A total of 123 Chinese primary caregivers of relatives with dementia were recruited from three elderly community care centers in Hong Kong. The FAS-C was administered with the Chinese versions of the 5-item Mental Health Inventory (MHI-5), the Zarit Burden Interview (ZBI) and the Revised Memory and Behavioral Problem Checklist (RMBPC). The FAS-C had excellent semantic equivalence with the original version and a content validity index of 0.92. Exploratory factor analysis identified a three-factor structure for the FAS-C (hostile acts, criticism and distancing). Cronbach's alpha of the FAS-C was 0.92. Pearson's correlation indicated that there were significant associations between a higher score on the FAS-C and greater caregiver burden (r=0.66, p47 with a sensitivity of 0.720 (95% CI=0.506-0.879) and specificity of 0.742 (95% CI=0.643-0.826). The FAS-C is a reliable and valid measure to assess the affective quality of the relationship between Chinese caregivers and their relatives with dementia. It also has acceptable predictability in

  18. Functional neuroimaging of Alzheimer's disease and other dementias

    International Nuclear Information System (INIS)

    Wang Ruimin

    2001-01-01

    Dementing illnesses comprise Alzheimer's disease (AD), Pick's disease, Multi-infarct dementia (MID) and other neurological disorders. These diseases have different clinical characters respectively. Neuropsychological examinations can help to diagnose and differential diagnose dementias. The development of neuroimaging dementias is more and more rapid. 18 F-FDG PET method shows neo-cortical hypometabolism occurring in the biparietal-temporal lobes and left-right asymmetry of AD patients in the early stage. It can also differential diagnose Ad from other dementias

  19. Semantic attributes based texture generation

    Science.gov (United States)

    Chi, Huifang; Gan, Yanhai; Qi, Lin; Dong, Junyu; Madessa, Amanuel Hirpa

    2018-04-01

    Semantic attributes are commonly used for texture description. They can be used to describe the information of a texture, such as patterns, textons, distributions, brightness, and so on. Generally speaking, semantic attributes are more concrete descriptors than perceptual features. Therefore, it is practical to generate texture images from semantic attributes. In this paper, we propose to generate high-quality texture images from semantic attributes. Over the last two decades, several works have been done on texture synthesis and generation. Most of them focusing on example-based texture synthesis and procedural texture generation. Semantic attributes based texture generation still deserves more devotion. Gan et al. proposed a useful joint model for perception driven texture generation. However, perceptual features are nonobjective spatial statistics used by humans to distinguish different textures in pre-attentive situations. To give more describing information about texture appearance, semantic attributes which are more in line with human description habits are desired. In this paper, we use sigmoid cross entropy loss in an auxiliary model to provide enough information for a generator. Consequently, the discriminator is released from the relatively intractable mission of figuring out the joint distribution of condition vectors and samples. To demonstrate the validity of our method, we compare our method to Gan et al.'s method on generating textures by designing experiments on PTD and DTD. All experimental results show that our model can generate textures from semantic attributes.

  20. Generative Semantics.

    Science.gov (United States)

    King, Margaret

    The first section of this paper deals with the attempts within the framework of transformational grammar to make semantics a systematic part of linguistic description, and outlines the characteristics of the generative semantics position. The second section takes a critical look at generative semantics in its later manifestations, and makes a case…

  1. MR spectroscopy in dementia

    International Nuclear Information System (INIS)

    Hauser, T.; Gerigk, L.; Giesel, F.; Schuster, L.; Essig, M.

    2010-01-01

    With an increasingly aging population we are faced with the problem of an increasing number of dementia patients. In addition to clinical, neuropsychological and laboratory procedures, MRI plays an important role in the early diagnosis of dementia. In addition to various morphological changes functional changes can also help in the diagnosis and differential diagnosis of dementia. Overall the diagnosis of dementia can be improved by using parameters from MR spectroscopy. This article focuses on MR spectroscopic changes in the physiological aging process as well as on changes in mild cognitive impairment a precursor of Alzheimer's dementia, in Alzheimer's dementia, frontotemporal dementia, vascular dementia and Lewy body dementia. (orig.) [de

  2. FDG PET imaging dementia

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Byeong Cheol [Kyungpook National University Medical School and Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2007-04-15

    Dementia is a major burden for many countries including South Korea, where life expectancy is continuously growing and the proportion of aged people is rapidly growing. Neurodegenerative disorders, such as, Alzheimer disease, dementia with Lewy bodies, frontotemporal dementia. Parkinson disease, progressive supranuclear palsy, corticobasal degeneration, Huntington disease, can cause dementia, and cerebrovascular disease also can cause dementia. Depression or hypothyroidism also can cause cognitive deficits, but they are reversible by management of underlying cause unlike the forementioned dementias. Therefore these are called pseudodementia. We are entering an era of dementia care that will be based upon the identification of potentially modifiable risk factors and early disease markers, and the application of new drugs postpone progression of dementias or target specific proteins that cause dementia. Efficient pharmacologic treatment of dementia needs not only to distinguish underlying causes of dementia but also to be installed as soon as possible. Therefore, differential diagnosis and early diagnosis of dementia are utmost importance. F-18 FDG PET is useful for clarifying dementing diseases and is also useful for early detection of the disease. Purpose of this article is to review the current value of FDG PET for dementing diseases including differential diagnosis of dementia and prediction of evolving dementia.

  3. FDG PET imaging dementia

    International Nuclear Information System (INIS)

    Ahn, Byeong Cheol

    2007-01-01

    Dementia is a major burden for many countries including South Korea, where life expectancy is continuously growing and the proportion of aged people is rapidly growing. Neurodegenerative disorders, such as, Alzheimer disease, dementia with Lewy bodies, frontotemporal dementia. Parkinson disease, progressive supranuclear palsy, corticobasal degeneration, Huntington disease, can cause dementia, and cerebrovascular disease also can cause dementia. Depression or hypothyroidism also can cause cognitive deficits, but they are reversible by management of underlying cause unlike the forementioned dementias. Therefore these are called pseudodementia. We are entering an era of dementia care that will be based upon the identification of potentially modifiable risk factors and early disease markers, and the application of new drugs postpone progression of dementias or target specific proteins that cause dementia. Efficient pharmacologic treatment of dementia needs not only to distinguish underlying causes of dementia but also to be installed as soon as possible. Therefore, differential diagnosis and early diagnosis of dementia are utmost importance. F-18 FDG PET is useful for clarifying dementing diseases and is also useful for early detection of the disease. Purpose of this article is to review the current value of FDG PET for dementing diseases including differential diagnosis of dementia and prediction of evolving dementia

  4. Relationship Structures and Semantic Type Assignments of the UMLS Enriched Semantic Network

    Science.gov (United States)

    Zhang, Li; Halper, Michael; Perl, Yehoshua; Geller, James; Cimino, James J.

    2005-01-01

    Objective: The Enriched Semantic Network (ESN) was introduced as an extension of the Unified Medical Language System (UMLS) Semantic Network (SN). Its multiple subsumption configuration and concomitant multiple inheritance make the ESN's relationship structures and semantic type assignments different from those of the SN. A technique for deriving the relationship structures of the ESN's semantic types and an automated technique for deriving the ESN's semantic type assignments from those of the SN are presented. Design: The technique to derive the ESN's relationship structures finds all newly inherited relationships in the ESN. All such relationships are audited for semantic validity, and the blocking mechanism is used to block invalid relationships. The mapping technique to derive the ESN's semantic type assignments uses current SN semantic type assignments and preserves nonredundant categorizations, while preventing new redundant categorizations. Results: Among the 426 newly inherited relationships, 326 are deemed valid. Seven blockings are applied to avoid inheritance of the 100 invalid relationships. Sixteen semantic types have different relationship structures in the ESN as compared to those in the SN. The mapping of semantic type assignments from the SN to the ESN avoids the generation of 26,950 redundant categorizations. The resulting ESN contains 138 semantic types, 149 IS-A links, 7,303 relationships, and 1,013,876 semantic type assignments. Conclusion: The ESN's multiple inheritance provides more complete relationship structures than in the SN. The ESN's semantic type assignments avoid the existing redundant categorizations appearing in the SN and prevent new ones that might arise due to multiple parents. Compared to the SN, the ESN provides a more accurate unifying semantic abstraction of the UMLS Metathesaurus. PMID:16049233

  5. Towards Compatible and Interderivable Semantic Specifications for the Scheme Programming Language, Part II: Reduction Semantics and Abstract Machines

    DEFF Research Database (Denmark)

    Biernacka, Malgorzata; Danvy, Olivier

    2009-01-01

    We present a context-sensitive reduction semantics for a lambmda-calculus with explicit substitutions and we show that the functional implementation of this small-step semantics mechanically corresponds to that of the abstract machine for Core Scheme presented by Clinger at PLDI'98, including fir...

  6. Altered Neural Activity during Semantic Object Memory Retrieval in Amnestic Mild Cognitive Impairment as Measured by Event-Related Potentials.

    Science.gov (United States)

    Chiang, Hsueh-Sheng; Mudar, Raksha A; Pudhiyidath, Athula; Spence, Jeffrey S; Womack, Kyle B; Cullum, C Munro; Tanner, Jeremy A; Eroh, Justin; Kraut, Michael A; Hart, John

    2015-01-01

    Deficits in semantic memory in individuals with amnestic mild cognitive impairment (aMCI) have been previously reported, but the underlying neurobiological mechanisms remain to be clarified. We examined event-related potentials (ERPs) associated with semantic memory retrieval in 16 individuals with aMCI as compared to 17 normal controls using the Semantic Object Retrieval Task (EEG SORT). In this task, subjects judged whether pairs of words (object features) elicited retrieval of an object (retrieval trials) or not (non-retrieval trials). Behavioral findings revealed that aMCI subjects had lower accuracy scores and marginally longer reaction time compared to controls. We used a multivariate analytical technique (STAT-PCA) to investigate similarities and differences in ERPs between aMCI and control groups. STAT-PCA revealed a left fronto-temporal component starting at around 750 ms post-stimulus in both groups. However, unlike controls, aMCI subjects showed an increase in the frontal-parietal scalp potential that distinguished retrieval from non-retrieval trials between 950 and 1050 ms post-stimulus negatively correlated with the performance on the logical memory subtest of the Wechsler Memory Scale-III. Thus, individuals with aMCI were not only impaired in their behavioral performance on SORT relative to controls, but also displayed alteration in the corresponding ERPs. The altered neural activity in aMCI compared to controls suggests a more sustained and effortful search during object memory retrieval, which may be a potential marker indicating disease processes at the pre-dementia stage.

  7. Dementia

    Science.gov (United States)

    ... continue to look for new genes that may be responsible for the development of Alzheimer’s disease and other forms of dementia. Several research projects hope to identify dementia biomarkers (measurable biological signs ...

  8. Dementia

    Science.gov (United States)

    ... aging. Many different diseases can cause dementia, including Alzheimer's disease and stroke. Drugs are available to treat some of these diseases. While these drugs cannot cure dementia or repair brain damage, they may improve ...

  9. Characteristics of cerebral glucose utilization in dementia

    Energy Technology Data Exchange (ETDEWEB)

    Matsuzawa, Taiju; Matsui, Hiroshige; Meguro, Kenichi; Ueda, Masamichi; Yamada, Kenji; Yamaguchi, Tatsuo; Itoh, Masatoshi; Hatazawa, Jun; Kinomura, Shigeo (Tohoku Univ., Sendai (Japan). Research Inst. for Tuberculosis and Cancer)

    1990-12-01

    To make clear the characteristics of cerebral glucose utilization in dementia, PET studies with 18F-FDG were carried out. Taking the pattern of 18F-FDG utilization, dementia can be subdivided into two types. One type shows a simultaneous and symmetrical reduction glucose utilization in the posterior part of neocortex covering the temporal, parietal and occipital association cortices. This is referred to as type I. Although this type constitutes only about 1/5 of all dementia patients, it is considered the fundamental type of dementia. Aside from this, there is type wherein a simultaneous and symmetrical reduction in glucose utilization of the neocortex. This is type II. It constitutes about 4/5 of all dementia patients which is far more type I. There are no essential difference in the characteristics of cerebral glucose utilization in AD and MID. However, with regards the mean, AD is lower than MID. Various organic defect in neocortex do not correlate with the global reduction in glucose utilization in dementia patients. These results suggest that the reduction in glucose utilization in dementia may be functional disorder. (author).

  10. Characteristics of cerebral glucose utilization in dementia

    International Nuclear Information System (INIS)

    Matsuzawa, Taiju; Matsui, Hiroshige; Meguro, Kenichi; Ueda, Masamichi; Yamada, Kenji; Yamaguchi, Tatsuo; Itoh, Masatoshi; Hatazawa, Jun; Kinomura, Shigeo

    1990-01-01

    To make clear the characteristics of cerebral glucose utilization in dementia, PET studies with 18F-FDG were carried out. Taking the pattern of 18F-FDG utilization, dementia can be subdivided into two types. One type shows a simultaneous and symmetrical reduction glucose utilization in the posterior part of neocortex covering the temporal, parietal and occipital association cortices. This is referred to as type I. Although this type constitutes only about 1/5 of all dementia patients, it is considered the fundamental type of dementia. Aside from this, there is type wherein a simultaneous and symmetrical reduction in glucose utilization of the neocortex. This is type II. It constitutes about 4/5 of all dementia patients which is far more type I. There are no essential difference in the characteristics of cerebral glucose utilization in AD and MID. However, with regards the mean, AD is lower than MID. Various organic defect in neocortex do not correlate with the global reduction in glucose utilization in dementia patients. These results suggest that the reduction in glucose utilization in dementia may be functional disorder. (author)

  11. Recommendations based on semantically enriched museum collections

    NARCIS (Netherlands)

    Wang, Y.; Stash, N.; Aroyo, L.M.; Gorgels, P.; Rutledge, L.W.; Schreiber, G.

    2008-01-01

    This article presents the CHIP demonstrator1 for providing personalized access to digital museum collections. It consists of three main components: Art Recommender, Tour Wizard, and Mobile Tour Guide. Based on the semantically enriched Rijksmuseum Amsterdam2 collection, we show how Semantic Web

  12. Concealed semantic and episodic autobiographical memory electrified.

    Science.gov (United States)

    Ganis, Giorgio; Schendan, Haline E

    2012-01-01

    Electrophysiology-based concealed information tests (CIT) try to determine whether somebody possesses concealed information about a crime-related item (probe) by comparing event-related potentials (ERPs) between this item and comparison items (irrelevants). Although the broader field is sometimes referred to as "memory detection," little attention has been paid to the precise type of underlying memory involved. This study begins addressing this issue by examining the key distinction between semantic and episodic memory in the autobiographical domain within a CIT paradigm. This study also addresses the issue of whether multiple repetitions of the items over the course of the session habituate the brain responses. Participants were tested in a 3-stimulus CIT with semantic autobiographical probes (their own date of birth) and episodic autobiographical probes (a secret date learned just before the study). Results dissociated these two memory conditions on several ERP components. Semantic probes elicited a smaller frontal N2 than episodic probes, consistent with the idea that the frontal N2 decreases with greater pre-existing knowledge about the item. Likewise, semantic probes elicited a smaller central N400 than episodic probes. Semantic probes also elicited a larger P3b than episodic probes because of their richer meaning. In contrast, episodic probes elicited a larger late positive complex (LPC) than semantic probes, because of the recent episodic memory associated with them. All these ERPs showed a difference between probes and irrelevants in both memory conditions, except for the N400, which showed a difference only in the semantic condition. Finally, although repetition affected the ERPs, it did not reduce the difference between probes and irrelevants. These findings show that the type of memory associated with a probe has both theoretical and practical importance for CIT research.

  13. Concealed semantic and episodic autobiographical memory electrified

    Science.gov (United States)

    Ganis, Giorgio; Schendan, Haline E.

    2013-01-01

    Electrophysiology-based concealed information tests (CIT) try to determine whether somebody possesses concealed information about a crime-related item (probe) by comparing event-related potentials (ERPs) between this item and comparison items (irrelevants). Although the broader field is sometimes referred to as “memory detection,” little attention has been paid to the precise type of underlying memory involved. This study begins addressing this issue by examining the key distinction between semantic and episodic memory in the autobiographical domain within a CIT paradigm. This study also addresses the issue of whether multiple repetitions of the items over the course of the session habituate the brain responses. Participants were tested in a 3-stimulus CIT with semantic autobiographical probes (their own date of birth) and episodic autobiographical probes (a secret date learned just before the study). Results dissociated these two memory conditions on several ERP components. Semantic probes elicited a smaller frontal N2 than episodic probes, consistent with the idea that the frontal N2 decreases with greater pre-existing knowledge about the item. Likewise, semantic probes elicited a smaller central N400 than episodic probes. Semantic probes also elicited a larger P3b than episodic probes because of their richer meaning. In contrast, episodic probes elicited a larger late positive complex (LPC) than semantic probes, because of the recent episodic memory associated with them. All these ERPs showed a difference between probes and irrelevants in both memory conditions, except for the N400, which showed a difference only in the semantic condition. Finally, although repetition affected the ERPs, it did not reduce the difference between probes and irrelevants. These findings show that the type of memory associated with a probe has both theoretical and practical importance for CIT research. PMID:23355816

  14. Dementia and Hospital Readmission Rates: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Sabrina Pickens

    2017-10-01

    Full Text Available Background: Although community-dwelling persons with dementia have an increased risk of hospital readmission, no systematic review has examined the contribution of dementia to readmissions. Summary: We examined articles in English, with no restrictions on publication dates, from Medline, PubMed, PsycINFO, CINAHL, and EMBASE. Keywords used were dementia, Alzheimer disease, frontotemporal lobar degeneration, elderly, frontotemporal dementia, executive function, brain atrophy, frontal lobe atrophy, cognitive impairment, readmission, readmit, rehospitalization, patient discharge, and return visit. Of 404 abstracts identified, 77 articles were retrieved; 12 were included. Four of 5 cohort studies showed significantly increased readmission rates in patients with dementia. On average the absolute increase above the comparison groups was from 3 to 13%. Dementia was not associated with readmission in 7 included case-control studies. Key Message: Findings suggest a small increased risk of hospital readmission in individuals with dementia. More study is needed.

  15. Bilingualism delays the onset of behavioral but not aphasic forms of frontotemporal dementia.

    Science.gov (United States)

    Alladi, Suvarna; Bak, Thomas H; Shailaja, Mekala; Gollahalli, Divyaraj; Rajan, Amulya; Surampudi, Bapiraju; Hornberger, Michael; Duggirala, Vasanta; Chaudhuri, Jaydip Ray; Kaul, Subhash

    2017-05-01

    Bilingualism has been found to delay onset of dementia and this has been attributed to an advantage in executive control in bilinguals. However, the relationship between bilingualism and cognition is complex, with costs as well as benefits to language functions. To further explore the cognitive consequences of bilingualism, the study used Frontotemporal dementia (FTD) syndromes, to examine whether bilingualism modifies the age at onset of behavioral and language variants of Frontotemporal dementia (FTD) differently. Case records of 193 patients presenting with FTD (121 of them bilingual) were examined and the age at onset of the first symptoms were compared between monolinguals and bilinguals. A significant effect of bilingualism delaying the age at onset of dementia was found in behavioral variant FTD (5.7 years) but not in progressive nonfluent aphasia (0.7 years), semantic dementia (0.5 years), corticobasal syndrome (0.4 years), progressive supranuclear palsy (4.3 years) and FTD-motor neuron disease (3 years). On dividing all patients predominantly behavioral and predominantly aphasic groups, age at onset in the bilingual behavioral group (62.6) was over 6 years higher than in the monolingual patients (56.5, p=0.006), while there was no difference in the aphasic FTD group (60.9 vs. 60.6 years, p=0.851). The bilingual effect on age of bvFTD onset was shown independently of other potential confounding factors such as education, gender, occupation, and urban vs rural dwelling of subjects. To conclude, bilingualism delays the age at onset in the behavioral but not in the aphasic variants of FTD. The results are in line with similar findings based on research in stroke and with the current views of the interaction between bilingualism and cognition, pointing to advantages in executive functions and disadvantages in lexical tasks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Phonological and semantic strategies in immediate serial recall.

    Science.gov (United States)

    Campoy, Guillermo; Baddeley, Alan

    2008-05-01

    It has been suggested that certain theoretically important anomalous results in the area of verbal short-term memory could be attributable to differences in strategy. However there are relatively few studies that investigate strategy directly. We describe four experiments, each involving the immediate serial recall of word sequences under baseline control conditions, or preceded by instruction to use a phonological or semantic strategy. Two experiments varied phonological similarity at a presentation rate of one item every 1 or 2 seconds. Both the control and the phonologically instructed group showed clear effects of similarity at both presentation rates, whereas these were largely absent under semantic encoding conditions. Two further experiments manipulated word length at the same two rates. The phonologically instructed groups showed clear effects at both rates, the control group showed a clear effect at the rapid rate which diminished with the slower presentation, while the semantically instructed group showed a relatively weak effect at the rate of one item per second, and a significant reverse effect with slower presentation. The latter finding is interpreted in terms of fortuitous differences in inter-item rated associability between the two otherwise matched word pools, reinforcing our conclusion that the semantically instructed group were indeed encoding semantically. Implications for controlling strategy by instruction are discussed.

  17. The (null impact of pseudohomophones in lexical decision: No phonological activation in semantic dementia?

    Directory of Open Access Journals (Sweden)

    Maximiliano A. Wilson

    2014-04-01

    The results in controls reproduce those found in literature (Braun et al., 2009. The general impairment and the lack of lexicality effect are also in line with current literature on svPPA and are likely explained by semantic impairment (Rogers et al., 2004. Interestingly, the novel result here is the absence of PsH effect in svPPA. This suggests that phonology is not correctly activated and that O-P mappings are also impaired in svPPA.

  18. Tools to Detect Delirium Superimposed on Dementia: A Systematic Review

    Science.gov (United States)

    Morandi, Alessandro; McCurley, Jessica; Vasilevskis, Eduard E.; Fick, Donna M.; Bellelli, Giuseppe; Lee, Patricia; Jackson, James C.; Shenkin, Susan D.; Trabucchi, Marco; Schnelle, John; Inouye, Sharon K.; Ely, Wesley E.; MacLullich, Alasdair

    2012-01-01

    Background Delirium commonly occurs in patients with dementia. Though several tools for detecting delirium exist, it is unclear which are valid in patients with delirium superimposed on dementia. Objectives Identify valid tools to diagnose delirium superimposed on dementia Design We performed a systematic review of studies of delirium tools, which explicitly included patients with dementia. Setting In-hospital patients Participants Studies were included if delirium assessment tools were validated against standard criteria, and the presence of dementia was assessed according to standard criteria that used validated instruments. Measurements PubMed, Embase, and Web of Science databases were searched for articles in English published between January 1960 and January 2012. Results Nine studies fulfilled the selection criteria. Of the total of 1569 patients, 401 had dementia, and 50 had delirium superimposed on dementia. Six delirium tools were evaluated. One studyusing the Confusion Assessment Method (CAM) with 85% patients with dementia showed a high specificity (96–100%) and moderate sensitivity (77%).Two intensive care unit studies that used the CAM for the Intensive Care Unit (CAM-ICU) ICU reported 100% sensitivity and specificity for delirium among 23 dementia patients. One study using electroencephalography reported a sensitivity of 67% and a specificity of 91% among a population with 100% prevalence of dementia. No studies examined potential effects of dementia severity or subtype upon diagnostic accuracy. Conclusions The evidence base on tools for detection of delirium superimposed on dementia is limited, although some existing tools show promise. Further studies of existing or refined tools with larger samples and more detailed characterization of dementia are now required to address the identification of delirium superimposed on dementia. PMID:23039270

  19. Age of acquisition and naming performance in Frisian-Dutch bilingual speakers with dementia.

    Science.gov (United States)

    Veenstra, Wencke S; Huisman, Mark; Miller, Nick

    2014-01-01

    Age of acquisition (AoA) of words is a recognised variable affecting language processing in speakers with and without language disorders. For bi- and multilingual speakers their languages can be differentially affected in neurological illness. Study of language loss in bilingual speakers with dementia has been relatively neglected. We investigated whether AoA of words was associated with level of naming impairment in bilingual speakers with probable Alzheimer's dementia within and across their languages. Twenty-six Frisian-Dutch bilinguals with mild to moderate dementia named 90 pictures in each language, employing items with rated AoA and other word variable measures matched across languages. Quantitative (totals correct) and qualitative (error types and (in)appropriate switching) aspects were measured. Impaired retrieval occurred in Frisian (Language 1) and Dutch (Language 2), with a significant effect of AoA on naming in both languages. Earlier acquired words were better preserved and retrieved. Performance was identical across languages, but better in Dutch when controlling for covariates. However, participants demonstrated more inappropriate code switching within the Frisian test setting. On qualitative analysis, no differences in overall error distribution were found between languages for early or late acquired words. There existed a significantly higher percentage of semantically than visually-related errors. These findings have implications for understanding problems in lexical retrieval among bilingual individuals with dementia and its relation to decline in other cognitive functions which may play a role in inappropriate code switching. We discuss the findings in the light of the close relationship between Frisian and Dutch and the pattern of usage across the life-span.

  20. Ontology Matching with Semantic Verification.

    Science.gov (United States)

    Jean-Mary, Yves R; Shironoshita, E Patrick; Kabuka, Mansur R

    2009-09-01

    ASMOV (Automated Semantic Matching of Ontologies with Verification) is a novel algorithm that uses lexical and structural characteristics of two ontologies to iteratively calculate a similarity measure between them, derives an alignment, and then verifies it to ensure that it does not contain semantic inconsistencies. In this paper, we describe the ASMOV algorithm, and then present experimental results that measure its accuracy using the OAEI 2008 tests, and that evaluate its use with two different thesauri: WordNet, and the Unified Medical Language System (UMLS). These results show the increased accuracy obtained by combining lexical, structural and extensional matchers with semantic verification, and demonstrate the advantage of using a domain-specific thesaurus for the alignment of specialized ontologies.

  1. Self-referential processing is distinct from semantic elaboration: evidence from long-term memory effects in a patient with amnesia and semantic impairments.

    Science.gov (United States)

    Sui, Jie; Humphreys, Glyn W

    2013-11-01

    We report data demonstrating that self-referential encoding facilitates memory performance in the absence of effects of semantic elaboration in a severely amnesic patient also suffering semantic problems. In Part 1, the patient, GA, was trained to associate items with the self or a familiar other during the encoding phase of a memory task (self-ownership decisions in Experiment 1 and self-evaluation decisions in Experiment 2). Tests of memory showed a consistent self-reference advantage, relative to a condition where the reference was another person in both experiments. The pattern of the self-reference advantage was similar to that in healthy controls. In Part 2 we demonstrate that GA showed minimal effects of semantic elaboration on memory for items he semantically classified, compared with items subject to physical size decisions; in contrast, healthy controls demonstrated enhanced memory performance after semantic relative to physical encoding. The results indicate that self-referential encoding, not semantic elaboration, improves memory in amnesia. Self-referential processing may provide a unique scaffold to help improve learning in amnesic cases. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Auditory Distraction in Semantic Memory: A Process-Based Approach

    Science.gov (United States)

    Marsh, John E.; Hughes, Robert W.; Jones, Dylan M.

    2008-01-01

    Five experiments demonstrate auditory-semantic distraction in tests of memory for semantic category-exemplars. The effects of irrelevant sound on category-exemplar recall are shown to be functionally distinct from those found in the context of serial short-term memory by showing sensitivity to: The lexical-semantic, rather than acoustic,…

  3. The MMI Semantic Framework: Rosetta Stones for Earth Sciences

    Science.gov (United States)

    Rueda, C.; Bermudez, L. E.; Graybeal, J.; Alexander, P.

    2009-12-01

    Semantic interoperability—the exchange of meaning among computer systems—is needed to successfully share data in Ocean Science and across all Earth sciences. The best approach toward semantic interoperability requires a designed framework, and operationally tested tools and infrastructure within that framework. Currently available technologies make a scientific semantic framework feasible, but its development requires sustainable architectural vision and development processes. This presentation outlines the MMI Semantic Framework, including recent progress on it and its client applications. The MMI Semantic Framework consists of tools, infrastructure, and operational and community procedures and best practices, to meet short-term and long-term semantic interoperability goals. The design and prioritization of the semantic framework capabilities are based on real-world scenarios in Earth observation systems. We describe some key uses cases, as well as the associated requirements for building the overall infrastructure, which is realized through the MMI Ontology Registry and Repository. This system includes support for community creation and sharing of semantic content, ontology registration, version management, and seamless integration of user-friendly tools and application programming interfaces. The presentation describes the architectural components for semantic mediation, registry and repository for vocabularies, ontology, and term mappings. We show how the technologies and approaches in the framework can address community needs for managing and exchanging semantic information. We will demonstrate how different types of users and client applications exploit the tools and services for data aggregation, visualization, archiving, and integration. Specific examples from OOSTethys (http://www.oostethys.org) and the Ocean Observatories Initiative Cyberinfrastructure (http://www.oceanobservatories.org) will be cited. Finally, we show how semantic augmentation of web

  4. Semantic Desktop

    Science.gov (United States)

    Sauermann, Leo; Kiesel, Malte; Schumacher, Kinga; Bernardi, Ansgar

    In diesem Beitrag wird gezeigt, wie der Arbeitsplatz der Zukunft aussehen könnte und wo das Semantic Web neue Möglichkeiten eröffnet. Dazu werden Ansätze aus dem Bereich Semantic Web, Knowledge Representation, Desktop-Anwendungen und Visualisierung vorgestellt, die es uns ermöglichen, die bestehenden Daten eines Benutzers neu zu interpretieren und zu verwenden. Dabei bringt die Kombination von Semantic Web und Desktop Computern besondere Vorteile - ein Paradigma, das unter dem Titel Semantic Desktop bekannt ist. Die beschriebenen Möglichkeiten der Applikationsintegration sind aber nicht auf den Desktop beschränkt, sondern können genauso in Web-Anwendungen Verwendung finden.

  5. Semantic priming without association: a meta-analytic review.

    Science.gov (United States)

    Lucas, M

    2000-12-01

    A meta-analysis of 26 studies indicated that automatic semantic priming can occur without association. Priming did not vary substantially with differences in variables that affect automatic versus strategic processing, such as time spent processing the prime and target, relationship proportion, and task (except that average effects were smaller in the naming task). Although category coordinates were investigated in the majority of studies, synonyms, antonyms, and script relations also demonstrated priming; functional relations showed greater priming, and essential and perceptual relations showed less. The average effect size for semantic priming was smaller than that for associative priming, suggesting that there is an "associative boost" from adding an associative relationship to a semantic one. The implications of these findings for the modularity thesis and for models of semantic priming are discussed.

  6. Awareness of disease in dementia: Development of a multidimensional rating scale

    Directory of Open Access Journals (Sweden)

    Marcia Dourado

    Full Text Available Abstract Objective: To describe the development of the Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia (ASPIDD, a multidimensional scale to evaluate awareness of disease in dementia. Method: The development of this scale was conducted in four steps. In step one, questions were drawn up after a review of the literature. The second step involved the suggestions offered by a neurologist regarding the skills considered important for the scale. The third step involved the re-writing and review of the domains and questions in the scale followed by a semantic evaluation performed by two independent psychiatrists. Step four consisted of the preliminary study aimed at evaluating the applicability of the ASPIDD. Results: In the semantic evaluation only minor changes were proposed. The preliminary sample had 52 patients, comprising 23 CDR 1 (male=9; female=14 and 29 CDR2 (male=13; female=16. Mean age of patients was 69.7±5.51 (CDR1 and 73.6±9.4 (CDR2, and age at onset was 66.4±5.7 years (CDR1 and 68.3±9.3 year (CDR2. Mean schooling was 9.0±4.3 years (CDR1 and 8.8±4.4 years (CDR2. Mean MMSE was 21.0±3.3 (CDR1 and 17.6±3.5 (CDR2. Mean Cornell was 4.8±2.3 (CDR1 and 4.2±1.9 (CDR2. The patient and caregiver dyads were aware of problems, mainly of those related to social, family and affective relations. The higher rates of discrepant responses were found on the awareness of cognitive deficits and changes in ADL. Conclusion: The ASPIDD is a multidimensional instrument to assess awareness of disease among AD patients.

  7. Semantic heterogeneity: comparing new semantic web approaches with those of digital libraries

    OpenAIRE

    Krause, Jürgen

    2008-01-01

    To demonstrate that newer developments in the semantic web community, particularly those based on ontologies (simple knowledge organization system and others) mitigate common arguments from the digital library (DL) community against participation in the Semantic web. The approach is a semantic web discussion focusing on the weak structure of the Web and the lack of consideration given to the semantic content during indexing. The points criticised by the semantic web and ontology approaches ar...

  8. Lewy body dementias

    DEFF Research Database (Denmark)

    Løkkegaard, Annemette; Korbo, Lise

    2017-01-01

    Dementia with Lewy bodies and Parkinson disease dementia share the same pathophysiology. Together they are called Lewy body dementias and are the second most common type of dementia. Lewy body dementias receive little attention, and patients are often misdiagnosed, leading to less than ideal...... management. In this article, diagnostic criteria combined with imaging and other biomarkers as well as current treatment recommendations are summarized, and some of the challenges for the future are outlined. Refinement of diagnosis and clarification of the pathogenesis are required in search for disease...

  9. Concealed semantic and episodic autobiographical memory electrified

    Directory of Open Access Journals (Sweden)

    Giorgio eGanis

    2013-01-01

    Full Text Available Electrophysiology-based concealed information tests (CIT try to determine whether somebody possesses concealed information about a probe item by comparing event-related potentials (ERPs between this item and comparison items (irrelevants. Although the broader field is sometimes referred to as memory detection, little attention has been paid to the precise type of underlying memory involved. This study begins addressing this issue by examining the key distinction between semantic and episodic memory in the autobiographical domain within a CIT paradigm. This study also addressed the issue of whether multiple repetitions of the items over the course of the session habituate the brain responses. Participants were tested in a 3-stimulus CIT with semantic autobiographical probes (their own date of birth and episodic autobiographical probes (a secret date learned just before the study. Results dissociated these two memory conditions on several ERP components. Semantic probes elicited a smaller frontal N2 than episodic probes, consistent with the idea that the frontal N2 decreases with greater pre-existing semantic knowledge about the item. Likewise, semantic probes elicited a smaller central N400 than episodic probes. Semantic probes also elicited a larger P3b than episodic probes because of their richer meaning. In contrast, episodic probes elicited a larger late positive component (LPC than semantic probes, because of the recent episodic memory associated with them. All these ERPs showed a difference between probes and irrelevants in both memory conditions, except for the N400, which showed a difference only in the semantic condition. Finally, although repetition affected the ERPs, it did not reduce the difference between probes and irrelevants. Thus, the type of memory associated with a probe has both theoretical and practical importance for CIT research.

  10. Semantic framework for mapping object-oriented model to semantic web languages.

    Science.gov (United States)

    Ježek, Petr; Mouček, Roman

    2015-01-01

    The article deals with and discusses two main approaches in building semantic structures for electrophysiological metadata. It is the use of conventional data structures, repositories, and programming languages on one hand and the use of formal representations of ontologies, known from knowledge representation, such as description logics or semantic web languages on the other hand. Although knowledge engineering offers languages supporting richer semantic means of expression and technological advanced approaches, conventional data structures and repositories are still popular among developers, administrators and users because of their simplicity, overall intelligibility, and lower demands on technical equipment. The choice of conventional data resources and repositories, however, raises the question of how and where to add semantics that cannot be naturally expressed using them. As one of the possible solutions, this semantics can be added into the structures of the programming language that accesses and processes the underlying data. To support this idea we introduced a software prototype that enables its users to add semantically richer expressions into a Java object-oriented code. This approach does not burden users with additional demands on programming environment since reflective Java annotations were used as an entry for these expressions. Moreover, additional semantics need not to be written by the programmer directly to the code, but it can be collected from non-programmers using a graphic user interface. The mapping that allows the transformation of the semantically enriched Java code into the Semantic Web language OWL was proposed and implemented in a library named the Semantic Framework. This approach was validated by the integration of the Semantic Framework in the EEG/ERP Portal and by the subsequent registration of the EEG/ERP Portal in the Neuroscience Information Framework.

  11. The frontal-anatomic specificity of design fluency repetitions and their diagnostic relevance for behavioral variant frontotemporal dementia.

    Science.gov (United States)

    Possin, Katherine L; Chester, Serana K; Laluz, Victor; Bostrom, Alan; Rosen, Howard J; Miller, Bruce L; Kramer, Joel H

    2012-09-01

    On tests of design fluency, an examinee draws as many different designs as possible in a specified time limit while avoiding repetition. The neuroanatomical substrates and diagnostic group differences of design fluency repetition errors and total correct scores were examined in 110 individuals diagnosed with dementia, 53 with mild cognitive impairment (MCI), and 37 neurologically healthy controls. The errors correlated significantly with volumes in the right and left orbitofrontal cortex (OFC), the right and left superior frontal gyrus, the right inferior frontal gyrus, and the right striatum, but did not correlate with volumes in any parietal or temporal lobe regions. Regression analyses indicated that the lateral OFC may be particularly crucial for preventing these errors, even after excluding patients with behavioral variant frontotemporal dementia (bvFTD) from the analysis. Total correct correlated more diffusely with volumes in the right and left frontal and parietal cortex, the right temporal cortex, and the right striatum and thalamus. Patients diagnosed with bvFTD made significantly more repetition errors than patients diagnosed with MCI, Alzheimer's disease, semantic dementia, progressive supranuclear palsy, or corticobasal syndrome. In contrast, total correct design scores did not differentiate the dementia patients. These results highlight the frontal-anatomic specificity of design fluency repetitions. In addition, the results indicate that the propensity to make these errors supports the diagnosis of bvFTD. (JINS, 2012, 18, 1-11).

  12. Dysfunctions associated with dementia and their treatment

    Directory of Open Access Journals (Sweden)

    Roksana Malak

    2014-11-01

    Full Text Available [u]International UnderstAID project shows[/u] the role of physiotherapist in patients with dementia as divided into two branches: helping to resolve the physical problems and solving the problems related to dementia. The role of physiotherapist in dementia treatment may be divided into two branches: helping to resolve the physical problems and solving the problems related to dementia. The physical problems consider such aspects as musculoskeletal disorders, mobility dysfunction and pain. Referring to musculoskeletal problems, the interventions of physical therapists should included whole-body progressive resistance exercise training, strengthening, “range-of-motion” and stretching exercises and transfer training. Mobility disorders are associated with physical symptoms such as: rigidity, balance problem, shuffling gait. Decreased mobility can be based on unrelieved pain. These are some crucial scales which are designed to detected the pain. For instance, The Pain Assessment in Advanced Dementia. Transcutaneous Electrical Nerve Stimulation, massage or exercises can be provide to reduce the pain in patients with dementia. Physiotherapy in dementia treatment influences not only physical functions but also the maintenance or progression of cognitive abilities of demented elderly subjects

  13. Programming the semantic web

    CERN Document Server

    Segaran, Toby; Taylor, Jamie

    2009-01-01

    With this book, the promise of the Semantic Web -- in which machines can find, share, and combine data on the Web -- is not just a technical possibility, but a practical reality Programming the Semantic Web demonstrates several ways to implement semantic web applications, using current and emerging standards and technologies. You'll learn how to incorporate existing data sources into semantically aware applications and publish rich semantic data. Each chapter walks you through a single piece of semantic technology and explains how you can use it to solve real problems. Whether you're writing

  14. Cerebral blood flow changes in Parkinson's disease associated with dementia

    International Nuclear Information System (INIS)

    Derejko, M.; Lass, P.; Slawek, J.; Nyka, W.M.

    2001-01-01

    Dementia is one of the main non-motor symptoms of Parkinson's disease (PD) and it is diagnosed in about 30% of cases. Its aetiology remains unclear and contributing factors are controversial. Dementia may be more common in old patients with severe motor symptoms and mild cognitive impairment. Clinico-pathological studies show the association between dementia in PD and the age-related group of dementias, such as AD and VaD. A valuable aid in the assessment of dementia in PD is cerebral blood flow (CBF) brain SPECT scanning. It shows three different patterns of rCBF reduction, including frontal lobe hypoperfusion, iu Alzheimer-likel type of hypoperfusion and multiple, vascular defects. The heterogeneity of rCBF reduction may reflect the multifactorial pathophysiology of dementia in PD. It may result from concomitant AD pathology, cerebrovascular disease, destruction of nigro-striato-frontal projection or may be a distinct disease of different aetiology. (author)

  15. Parkinson's Disease Dementia

    Science.gov (United States)

    ... Find your local chapter Join our online community Parkinson's Disease Dementia Parkinson's disease dementia is an impairment ... disease. About Symptoms Diagnosis Causes & risks Treatments About Parkinson's disease dementia The brain changes caused by Parkinson's ...

  16. Semantic metrics

    OpenAIRE

    Hu, Bo; Kalfoglou, Yannis; Dupplaw, David; Alani, Harith; Lewis, Paul; Shadbolt, Nigel

    2006-01-01

    In the context of the Semantic Web, many ontology-related operations, e.g. ontology ranking, segmentation, alignment, articulation, reuse, evaluation, can be boiled down to one fundamental operation: computing the similarity and/or dissimilarity among ontological entities, and in some cases among ontologies themselves. In this paper, we review standard metrics for computing distance measures and we propose a series of semantic metrics. We give a formal account of semantic metrics drawn from a...

  17. Semantic Learning Service Personalized

    Directory of Open Access Journals (Sweden)

    Yibo Chen

    2012-02-01

    Full Text Available To provide users with more suitable and personalized service, personalization is widely used in various fields. Current e-Learning systems search for learning resources using information search technology, based on the keywords that selected or inputted by the user. Due to lack of semantic analysis for keywords and exploring the user contexts, the system cannot provide a good learning experiment. In this paper, we defined the concept and characteristic of the personalized learning service, and proposed a semantic learning service personalized framework. Moreover, we made full use of semantic technology, using ontologies to represent the learning contents and user profile, mining and utilizing the friendship and membership of the social relationship to construct the user social relationship profile, and improved the collaboration filtering algorithm to recommend personalized learning resources for users. The results of the empirical evaluation show that the approach is effectiveness in augmenting recommendation.

  18. Inquisitive semantics and pragmatics

    NARCIS (Netherlands)

    Groenendijk, J.; Roelofsen, F.; Larrazabal, J.M.; Zubeldia, L.

    2009-01-01

    This paper starts with an informal introduction to inquisitive semantics. After that, we present a formal definition of the semantics, and introduce the basic semantic notions of inquisitiveness and informativeness, in terms of wich we define the semantic categories of questions, assertions, and

  19. Music recognition in frontotemporal lobar degeneration and Alzheimer disease.

    Science.gov (United States)

    Johnson, Julene K; Chang, Chiung-Chih; Brambati, Simona M; Migliaccio, Raffaella; Gorno-Tempini, Maria Luisa; Miller, Bruce L; Janata, Petr

    2011-06-01

    To compare music recognition in patients with frontotemporal dementia, semantic dementia, Alzheimer disease, and controls and to evaluate the relationship between music recognition and brain volume. Recognition of familiar music depends on several levels of processing. There are few studies about how patients with dementia recognize familiar music. Subjects were administered tasks that assess pitch and melody discrimination, detection of pitch errors in familiar melodies, and naming of familiar melodies. There were no group differences on pitch and melody discrimination tasks. However, patients with semantic dementia had considerable difficulty naming familiar melodies and also scored the lowest when asked to identify pitch errors in the same melodies. Naming familiar melodies, but not other music tasks, was strongly related to measures of semantic memory. Voxel-based morphometry analysis of brain magnetic resonance imaging showed that difficulty in naming songs was associated with the bilateral temporal lobes and inferior frontal gyrus, whereas difficulty in identifying pitch errors in familiar melodies correlated with primarily the right temporal lobe. The results support a view that the anterior temporal lobes play a role in familiar melody recognition, and that musical functions are affected differentially across forms of dementia.

  20. Music Recognition in Frontotemporal Lobar Degeneration and Alzheimer Disease

    Science.gov (United States)

    Johnson, Julene K; Chang, Chiung-Chih; Brambati, Simona M; Migliaccio, Raffaella; Gorno-Tempini, Maria Luisa; Miller, Bruce L; Janata, Petr

    2013-01-01

    Objective To compare music recognition in patients with frontotemporal dementia, semantic dementia, Alzheimer disease, and controls and to evaluate the relationship between music recognition and brain volume. Background Recognition of familiar music depends on several levels of processing. There are few studies about how patients with dementia recognize familiar music. Methods Subjects were administered tasks that assess pitch and melody discrimination, detection of pitch errors in familiar melodies, and naming of familiar melodies. Results There were no group differences on pitch and melody discrimination tasks. However, patients with semantic dementia had considerable difficulty naming familiar melodies and also scored the lowest when asked to identify pitch errors in the same melodies. Naming familiar melodies, but not other music tasks, was strongly related to measures of semantic memory. Voxel-based morphometry analysis of brain MRI showed that difficulty in naming songs was associated with the bilateral temporal lobes and inferior frontal gyrus, whereas difficulty in identifying pitch errors in familiar melodies correlated with primarily the right temporal lobe. Conclusions The results support a view that the anterior temporal lobes play a role in familiar melody recognition, and that musical functions are affected differentially across forms of dementia. PMID:21617528

  1. SSWAP: A Simple Semantic Web Architecture and Protocol for semantic web services.

    Science.gov (United States)

    Gessler, Damian D G; Schiltz, Gary S; May, Greg D; Avraham, Shulamit; Town, Christopher D; Grant, David; Nelson, Rex T

    2009-09-23

    SSWAP (Simple Semantic Web Architecture and Protocol; pronounced "swap") is an architecture, protocol, and platform for using reasoning to semantically integrate heterogeneous disparate data and services on the web. SSWAP was developed as a hybrid semantic web services technology to overcome limitations found in both pure web service technologies and pure semantic web technologies. There are currently over 2400 resources published in SSWAP. Approximately two dozen are custom-written services for QTL (Quantitative Trait Loci) and mapping data for legumes and grasses (grains). The remaining are wrappers to Nucleic Acids Research Database and Web Server entries. As an architecture, SSWAP establishes how clients (users of data, services, and ontologies), providers (suppliers of data, services, and ontologies), and discovery servers (semantic search engines) interact to allow for the description, querying, discovery, invocation, and response of semantic web services. As a protocol, SSWAP provides the vocabulary and semantics to allow clients, providers, and discovery servers to engage in semantic web services. The protocol is based on the W3C-sanctioned first-order description logic language OWL DL. As an open source platform, a discovery server running at http://sswap.info (as in to "swap info") uses the description logic reasoner Pellet to integrate semantic resources. The platform hosts an interactive guide to the protocol at http://sswap.info/protocol.jsp, developer tools at http://sswap.info/developer.jsp, and a portal to third-party ontologies at http://sswapmeet.sswap.info (a "swap meet"). SSWAP addresses the three basic requirements of a semantic web services architecture (i.e., a common syntax, shared semantic, and semantic discovery) while addressing three technology limitations common in distributed service systems: i.e., i) the fatal mutability of traditional interfaces, ii) the rigidity and fragility of static subsumption hierarchies, and iii) the

  2. Episodic Memory in Alzheimer Disease, Frontotemporal Dementia, and Dementia With Lewy Bodies/Parkinson Disease Dementia: Disentangling Retrieval From Consolidation.

    Science.gov (United States)

    Economou, Alexandra; Routsis, Christopher; Papageorgiou, Sokratis G

    2016-01-01

    Differences in episodic memory performance in patients with Alzheimer disease (AD), frontotemporal dementia (FTD), dementia with Lewy bodies (DLB)/Parkinson disease with dementia (PDD) are inconsistent and task dependent. The inconsistencies may be attributed to the different tasks drawing on different memory processes. Few studies have examined episodic memory impairment in the above groups using memory tests that facilitate encoding, to distinguish memory deficits due to impairment of specific processes. We examined the memory performance of 106 AD patients, 51 FTD patients, 26 DLB/PDD patients, and 37 controls using the Five-Words Test, a 5-item memory test that facilitates encoding. The patient groups did not differ in modified Mini Mental State Examination scores. AD patients scored lowest on the Five-Words Test overall, and showed the greatest reduction from immediate total recall to delayed free recall relative to the other 2 groups, consistent with a predominantly consolidation deficit. DLB/PDD patients showed the largest improvement from delayed free to delayed total recall relative to the other 2 groups, consistent with a predominantly retrieval deficit. Deficits in both consolidation and retrieval underlie the memory impairment of the patients, to different extents, and contribute to the theoretical understanding of the nature of the memory impairment of the patient groups.

  3. FDG-PET and CSF biomarker accuracy in prediction of conversion to different dementias in a large multicentre MCI cohort.

    Science.gov (United States)

    Caminiti, Silvia Paola; Ballarini, Tommaso; Sala, Arianna; Cerami, Chiara; Presotto, Luca; Santangelo, Roberto; Fallanca, Federico; Vanoli, Emilia Giovanna; Gianolli, Luigi; Iannaccone, Sandro; Magnani, Giuseppe; Perani, Daniela

    2018-01-01

    In this multicentre study in clinical settings, we assessed the accuracy of optimized procedures for FDG-PET brain metabolism and CSF classifications in predicting or excluding the conversion to Alzheimer's disease (AD) dementia and non-AD dementias. We included 80 MCI subjects with neurological and neuropsychological assessments, FDG-PET scan and CSF measures at entry, all with clinical follow-up. FDG-PET data were analysed with a validated voxel-based SPM method. Resulting single-subject SPM maps were classified by five imaging experts according to the disease-specific patterns, as "typical-AD", "atypical-AD" (i.e. posterior cortical atrophy, asymmetric logopenic AD variant, frontal-AD variant), "non-AD" (i.e. behavioural variant FTD, corticobasal degeneration, semantic variant FTD; dementia with Lewy bodies) or "negative" patterns. To perform the statistical analyses, the individual patterns were grouped either as "AD dementia vs. non-AD dementia (all diseases)" or as "FTD vs. non-FTD (all diseases)". Aβ42, total and phosphorylated Tau CSF-levels were classified dichotomously, and using the Erlangen Score algorithm. Multivariate logistic models tested the prognostic accuracy of FDG-PET-SPM and CSF dichotomous classifications. Accuracy of Erlangen score and Erlangen Score aided by FDG-PET SPM classification was evaluated. The multivariate logistic model identified FDG-PET "AD" SPM classification (Expβ = 19.35, 95% C.I. 4.8-77.8, p CSF Aβ42 (Expβ = 6.5, 95% C.I. 1.64-25.43, p CSF biomarkers.

  4. SemanticOrganizer: A Customizable Semantic Repository for Distributed NASA Project Teams

    Science.gov (United States)

    Keller, Richard M.; Berrios, Daniel C.; Carvalho, Robert E.; Hall, David R.; Rich, Stephen J.; Sturken, Ian B.; Swanson, Keith J.; Wolfe, Shawn R.

    2004-01-01

    SemanticOrganizer is a collaborative knowledge management system designed to support distributed NASA projects, including diverse teams of scientists, engineers, and accident investigators. The system provides a customizable, semantically structured information repository that stores work products relevant to multiple projects of differing types. SemanticOrganizer is one of the earliest and largest semantic web applications deployed at NASA to date, and has been used in diverse contexts ranging from the investigation of Space Shuttle Columbia's accident to the search for life on other planets. Although the underlying repository employs a single unified ontology, access control and ontology customization mechanisms make the repository contents appear different for each project team. This paper describes SemanticOrganizer, its customization facilities, and a sampling of its applications. The paper also summarizes some key lessons learned from building and fielding a successful semantic web application across a wide-ranging set of domains with diverse users.

  5. [Electrophysiological bases of semantic processing of objects].

    Science.gov (United States)

    Kahlaoui, Karima; Baccino, Thierry; Joanette, Yves; Magnié, Marie-Noële

    2007-02-01

    How pictures and words are stored and processed in the human brain constitute a long-standing question in cognitive psychology. Behavioral studies have yielded a large amount of data addressing this issue. Generally speaking, these data show that there are some interactions between the semantic processing of pictures and words. However, behavioral methods can provide only limited insight into certain findings. Fortunately, Event-Related Potential (ERP) provides on-line cues about the temporal nature of cognitive processes and contributes to the exploration of their neural substrates. ERPs have been used in order to better understand semantic processing of words and pictures. The main objective of this article is to offer an overview of the electrophysiologic bases of semantic processing of words and pictures. Studies presented in this article showed that the processing of words is associated with an N 400 component, whereas pictures elicited both N 300 and N 400 components. Topographical analysis of the N 400 distribution over the scalp is compatible with the idea that both image-mediated concrete words and pictures access an amodal semantic system. However, given the distinctive N 300 patterns, observed only during picture processing, it appears that picture and word processing rely upon distinct neuronal networks, even if they end up activating more or less similar semantic representations.

  6. Dementia: role of MRI

    International Nuclear Information System (INIS)

    Georgieva-Kozarova, G.

    2012-01-01

    Full text: This presentation will focus on the role of MRI in the diagnosis of dementia and related diseases. We will discuss the following subjects: 1. Systematic assessment of MR in dementia 2. MR protocol for dementia 3. Typical findings in the most common dementia syndrome Alzheimer's disease (AD), Vascular Dementia (VaD), Frontotemporal lobe dementia (FTLD) 4. Short overview of neurodegenerative disorders which may be associated with dementia. The role of neuroimaging in dementia nowadays extends to support the diagnosis of specific neurodegenerative disorders. It is a challenge to the early diagnosis of neurodegenerative diseases such as Alzheimer's disease. Early diagnosis includes recognition of predementia conditions, such as mild cognitive impairment (MCI). Neuroimaging may also be used to assess disease progression and is adopted in current trials investigating MCI and AD. An MR-study of a patient suspected of having dementia must be assessed in a standardized way. First of all, treatable diseases like subdural hematomas, tumors and hydrocephalus need to be excluded. Next we should look for signs of specific dementias such as: Alzheimer's disease (AD): medial temporal lobe atrophy (MTA) and parietal atrophy. Frontotemporal Lobar Degeneration (FTLD): (asymmetric) frontal lobe atrophy and atrophy of the temporal pole. Vascular Dementia (VaD): global atrophy, diffuse white matter lesions, lacunas and 'strategic infarcts' (infarcts in regions that are involved in cognitive function). Dementia with Lewy bodies (DLB): in contrast to other forms of dementia usually no specific abnormalities. So when we study the MR images we should score in a systematic way for global atrophy, focal atrophy and for vascular disease (i.e. infarcts, white matter lesions, lacunas)

  7. LEARNING SEMANTICS-ENHANCED LANGUAGE MODELS APPLIED TO UNSUEPRVISED WSD

    Energy Technology Data Exchange (ETDEWEB)

    VERSPOOR, KARIN [Los Alamos National Laboratory; LIN, SHOU-DE [Los Alamos National Laboratory

    2007-01-29

    An N-gram language model aims at capturing statistical syntactic word order information from corpora. Although the concept of language models has been applied extensively to handle a variety of NLP problems with reasonable success, the standard model does not incorporate semantic information, and consequently limits its applicability to semantic problems such as word sense disambiguation. We propose a framework that integrates semantic information into the language model schema, allowing a system to exploit both syntactic and semantic information to address NLP problems. Furthermore, acknowledging the limited availability of semantically annotated data, we discuss how the proposed model can be learned without annotated training examples. Finally, we report on a case study showing how the semantics-enhanced language model can be applied to unsupervised word sense disambiguation with promising results.

  8. Exploiting semantic linkages among multiple sources for semantic information retrieval

    Science.gov (United States)

    Li, JianQiang; Yang, Ji-Jiang; Liu, Chunchen; Zhao, Yu; Liu, Bo; Shi, Yuliang

    2014-07-01

    The vision of the Semantic Web is to build a global Web of machine-readable data to be consumed by intelligent applications. As the first step to make this vision come true, the initiative of linked open data has fostered many novel applications aimed at improving data accessibility in the public Web. Comparably, the enterprise environment is so different from the public Web that most potentially usable business information originates in an unstructured form (typically in free text), which poses a challenge for the adoption of semantic technologies in the enterprise environment. Considering that the business information in a company is highly specific and centred around a set of commonly used concepts, this paper describes a pilot study to migrate the concept of linked data into the development of a domain-specific application, i.e. the vehicle repair support system. The set of commonly used concepts, including the part name of a car and the phenomenon term on the car repairing, are employed to build the linkage between data and documents distributed among different sources, leading to the fusion of documents and data across source boundaries. Then, we describe the approaches of semantic information retrieval to consume these linkages for value creation for companies. The experiments on two real-world data sets show that the proposed approaches outperform the best baseline 6.3-10.8% and 6.4-11.1% in terms of top five and top 10 precisions, respectively. We believe that our pilot study can serve as an important reference for the development of similar semantic applications in an enterprise environment.

  9. Learning With Social Semantic Technologies - Exploiting Latest Tools

    Directory of Open Access Journals (Sweden)

    Gisela Granitzer

    2008-12-01

    Full Text Available Even though it was only about three years ago that Social Software became a trend, it has become a common practice to utilize Social Software in learning institutions. It brought about a lot of advantages, but also challenges. Amounts of distributed and often unstructured user generated content make it difficult to meaningfully process and find relevant information. According to the estimate of the authors, the solution lies in underpinning Social Software with structure resulting in Social Semantic Software. In this contribution we introduce the central concepts Social Software, Semantic Web and Social Semantic Web and show how Social Semantic Technologies might be utilized in the higher education context.

  10. Getting connected: Both associative and semantic links structure semantic memory for newly learned persons.

    Science.gov (United States)

    Wiese, Holger; Schweinberger, Stefan R

    2015-01-01

    The present study examined whether semantic memory for newly learned people is structured by visual co-occurrence, shared semantics, or both. Participants were trained with pairs of simultaneously presented (i.e., co-occurring) preexperimentally unfamiliar faces, which either did or did not share additionally provided semantic information (occupation, place of living, etc.). Semantic information could also be shared between faces that did not co-occur. A subsequent priming experiment revealed faster responses for both co-occurrence/no shared semantics and no co-occurrence/shared semantics conditions, than for an unrelated condition. Strikingly, priming was strongest in the co-occurrence/shared semantics condition, suggesting additive effects of these factors. Additional analysis of event-related brain potentials yielded priming in the N400 component only for combined effects of visual co-occurrence and shared semantics, with more positive amplitudes in this than in the unrelated condition. Overall, these findings suggest that both semantic relatedness and visual co-occurrence are important when novel information is integrated into person-related semantic memory.

  11. Age of acquisition and naming performance in Frisian-Dutch bilingual speakers with dementia

    Directory of Open Access Journals (Sweden)

    Wencke S. Veenstra

    Full Text Available Age of acquisition (AoA of words is a recognised variable affecting language processing in speakers with and without language disorders. For bi- and multilingual speakers their languages can be differentially affected in neurological illness. Study of language loss in bilingual speakers with dementia has been relatively neglected.OBJECTIVE:We investigated whether AoA of words was associated with level of naming impairment in bilingual speakers with probable Alzheimer's dementia within and across their languages.METHODS:Twenty-six Frisian-Dutch bilinguals with mild to moderate dementia named 90 pictures in each language, employing items with rated AoA and other word variable measures matched across languages. Quantitative (totals correct and qualitative (error types and (inappropriate switching aspects were measured.RESULTSImpaired retrieval occurred in Frisian (Language 1 and Dutch (Language 2, with a significant effect of AoA on naming in both languages. Earlier acquired words were better preserved and retrieved. Performance was identical across languages, but better in Dutch when controlling for covariates. However, participants demonstrated more inappropriate code switching within the Frisian test setting. On qualitative analysis, no differences in overall error distribution were found between languages for early or late acquired words. There existed a significantly higher percentage of semantically than visually-related errors.CONCLUSIONThese findings have implications for understanding problems in lexical retrieval among bilingual individuals with dementia and its relation to decline in other cognitive functions which may play a role in inappropriate code switching. We discuss the findings in the light of the close relationship between Frisian and Dutch and the pattern of usage across the life-span.

  12. Word-embeddings Italian semantic spaces: A semantic model for psycholinguistic research

    Directory of Open Access Journals (Sweden)

    Marelli Marco

    2017-01-01

    Full Text Available Distributional semantics has been for long a source of successful models in psycholinguistics, permitting to obtain semantic estimates for a large number of words in an automatic and fast way. However, resources in this respect remain scarce or limitedly accessible for languages different from English. The present paper describes WEISS (Word-Embeddings Italian Semantic Space, a distributional semantic model based on Italian. WEISS includes models of semantic representations that are trained adopting state-of-the-art word-embeddings methods, applying neural networks to induce distributed representations for lexical meanings. The resource is evaluated against two test sets, demonstrating that WEISS obtains a better performance with respect to a baseline encoding word associations. Moreover, an extensive qualitative analysis of the WEISS output provides examples of the model potentialities in capturing several semantic phenomena. Two variants of WEISS are released and made easily accessible via web through the SNAUT graphic interface.

  13. Semantically Interoperable XML Data.

    Science.gov (United States)

    Vergara-Niedermayr, Cristobal; Wang, Fusheng; Pan, Tony; Kurc, Tahsin; Saltz, Joel

    2013-09-01

    XML is ubiquitously used as an information exchange platform for web-based applications in healthcare, life sciences, and many other domains. Proliferating XML data are now managed through latest native XML database technologies. XML data sources conforming to common XML schemas could be shared and integrated with syntactic interoperability. Semantic interoperability can be achieved through semantic annotations of data models using common data elements linked to concepts from ontologies. In this paper, we present a framework and software system to support the development of semantic interoperable XML based data sources that can be shared through a Grid infrastructure. We also present our work on supporting semantic validated XML data through semantic annotations for XML Schema, semantic validation and semantic authoring of XML data. We demonstrate the use of the system for a biomedical database of medical image annotations and markups.

  14. Semantically Interoperable XML Data

    Science.gov (United States)

    Vergara-Niedermayr, Cristobal; Wang, Fusheng; Pan, Tony; Kurc, Tahsin; Saltz, Joel

    2013-01-01

    XML is ubiquitously used as an information exchange platform for web-based applications in healthcare, life sciences, and many other domains. Proliferating XML data are now managed through latest native XML database technologies. XML data sources conforming to common XML schemas could be shared and integrated with syntactic interoperability. Semantic interoperability can be achieved through semantic annotations of data models using common data elements linked to concepts from ontologies. In this paper, we present a framework and software system to support the development of semantic interoperable XML based data sources that can be shared through a Grid infrastructure. We also present our work on supporting semantic validated XML data through semantic annotations for XML Schema, semantic validation and semantic authoring of XML data. We demonstrate the use of the system for a biomedical database of medical image annotations and markups. PMID:25298789

  15. Semantics of Kinship Terms in Tamil from the Semantic Typology Point of View

    Directory of Open Access Journals (Sweden)

    Анна Александровна Смирнитская

    2016-12-01

    Full Text Available In this article the author examines the lexical-semantic group “kinship terms” in Tamil, applying the attainments of modern semantic typology and the theory of semantic derivation. The kinship terms describing nuclear and extended family are explored. The “semantic shift” relation between two different meanings is established if such relation is realized by synchronous polysemy in one lexeme, semantic derivation, diachronic semantic change, cognates or some other means. The starting point of the study is the typological data from the DatSemShift catalogue of semantic shifts in languages of the world developed by a group of researchers under the guidance of Anna A. Zalizniak in the Institute of Linguistics, RAS. We verify the presence of semantic shifts described in the Database in Tamil. Also, we propose new semantic shifts specific only for this language. We confirm the presence of semantic relation of the studied type among the meanings with English “labels”: father - parents, girl - daughter, to deliver (a child - parents, - child, old woman - wife, owner - wife and others. The data also allows the assumption that the same relation exists between the meanings: old - grandfather, earth - mother, son - courage, unripe - son and others. The meanings of this field are the sources of semantic movements to abstract notions, lexicon of posession, forms of address and others; in addition many inner semantic relations inside this field are revealed. The meanings covering the nuclear part of the kinship system participate in universal semantic shifts described in the DatSemShift catalogue, while the meanings from collateral branches of this bifurcative kinship system (uncle, aunt turn out to be incomparable with kinship terms from indo-european lineal systems. Their meanings can be included in the DatSemShift catalogue only with an indication of system specifics. The information about semantic shifts can be useful for

  16. A break-even analysis for dementia care collaboration: Partners in Dementia Care.

    Science.gov (United States)

    Morgan, Robert O; Bass, David M; Judge, Katherine S; Liu, C F; Wilson, Nancy; Snow, A Lynn; Pirraglia, Paul; Garcia-Maldonado, Maurilio; Raia, Paul; Fouladi, N N; Kunik, Mark E

    2015-06-01

    Dementia is a costly disease. People with dementia, their families, and their friends are affected on personal, emotional, and financial levels. Prior work has shown that the "Partners in Dementia Care" (PDC) intervention addresses unmet needs and improves psychosocial outcomes and satisfaction with care. We examined whether PDC reduced direct Veterans Health Administration (VHA) health care costs compared with usual care. This study was a cost analysis of the PDC intervention in a 30-month trial involving five VHA medical centers. Study subjects were veterans (N = 434) 50 years of age and older with dementia and their caregivers at two intervention (N = 269) and three comparison sites (N = 165). PDC is a telephone-based care coordination and support service for veterans with dementia and their caregivers, delivered through partnerships between VHA medical centers and local Alzheimer's Association chapters. We tested for differences in total VHA health care costs, including hospital, emergency department, nursing home, outpatient, and pharmacy costs, as well as program costs for intervention participants. Covariates included caregiver reports of veterans' cognitive impairment, behavior problems, and personal care dependencies. We used linear mixed model regression to model change in log total cost post-baseline over a 1-year follow-up period. Intervention participants showed higher VHA costs than usual-care participants both before and after the intervention but did not differ significantly regarding change in log costs from pre- to post-baseline periods. Pre-baseline log cost (p ≤ 0.001), baseline cognitive impairment (p ≤ 0.05), number of personal care dependencies (p ≤ 0.01), and VA service priority (p ≤ 0.01) all predicted change in log total cost. These analyses show that PDC meets veterans' needs without significantly increasing VHA health care costs. PDC addresses the priority area of care coordination in the National Plan to Address Alzheimer

  17. Semantic Role Labeling

    CERN Document Server

    Palmer, Martha; Xue, Nianwen

    2011-01-01

    This book is aimed at providing an overview of several aspects of semantic role labeling. Chapter 1 begins with linguistic background on the definition of semantic roles and the controversies surrounding them. Chapter 2 describes how the theories have led to structured lexicons such as FrameNet, VerbNet and the PropBank Frame Files that in turn provide the basis for large scale semantic annotation of corpora. This data has facilitated the development of automatic semantic role labeling systems based on supervised machine learning techniques. Chapter 3 presents the general principles of applyin

  18. Functional Neuroimaging in Dementia

    NARCIS (Netherlands)

    J.M. Papma (Janne)

    2012-01-01

    textabstractDementia refers to a clinical syndrome of cognitive deterioration and difficulty in the performance of activities of daily living. The most common cause of dementia is Alzheimer’s disease (AD), followed by vascular dementia (VaD) at old age and frontotemporal dementia (FTD) at young

  19. GIF Video Sentiment Detection Using Semantic Sequence

    Directory of Open Access Journals (Sweden)

    Dazhen Lin

    2017-01-01

    Full Text Available With the development of social media, an increasing number of people use short videos in social media applications to express their opinions and sentiments. However, sentiment detection of short videos is a very challenging task because of the semantic gap problem and sequence based sentiment understanding problem. In this context, we propose a SentiPair Sequence based GIF video sentiment detection approach with two contributions. First, we propose a Synset Forest method to extract sentiment related semantic concepts from WordNet to build a robust SentiPair label set. This approach considers the semantic gap between label words and selects a robust label subset which is related to sentiment. Secondly, we propose a SentiPair Sequence based GIF video sentiment detection approach that learns the semantic sequence to understand the sentiment from GIF videos. Our experiment results on GSO-2016 (GIF Sentiment Ontology data show that our approach not only outperforms four state-of-the-art classification methods but also shows better performance than the state-of-the-art middle level sentiment ontology features, Adjective Noun Pairs (ANPs.

  20. Representations for Semantic Learning Webs: Semantic Web Technology in Learning Support

    Science.gov (United States)

    Dzbor, M.; Stutt, A.; Motta, E.; Collins, T.

    2007-01-01

    Recent work on applying semantic technologies to learning has concentrated on providing novel means of accessing and making use of learning objects. However, this is unnecessarily limiting: semantic technologies will make it possible to develop a range of educational Semantic Web services, such as interpretation, structure-visualization, support…

  1. Personal semantics: Is it distinct from episodic and semantic memory? An electrophysiological study of memory for autobiographical facts and repeated events in honor of Shlomo Bentin.

    Science.gov (United States)

    Renoult, Louis; Tanguay, Annick; Beaudry, Myriam; Tavakoli, Paniz; Rabipour, Sheida; Campbell, Kenneth; Moscovitch, Morris; Levine, Brian; Davidson, Patrick S R

    2016-03-01

    Declarative memory is thought to consist of two independent systems: episodic and semantic. Episodic memory represents personal and contextually unique events, while semantic memory represents culturally-shared, acontextual factual knowledge. Personal semantics refers to aspects of declarative memory that appear to fall somewhere in between the extremes of episodic and semantic. Examples include autobiographical knowledge and memories of repeated personal events. These two aspects of personal semantics have been studied little and rarely compared to both semantic and episodic memory. We recorded the event-related potentials (ERPs) of 27 healthy participants while they verified the veracity of sentences probing four types of questions: general (i.e., semantic) facts, autobiographical facts, repeated events, and unique (i.e., episodic) events. Behavioral results showed equivalent reaction times in all 4 conditions. True sentences were verified faster than false sentences, except for unique events for which no significant difference was observed. Electrophysiological results showed that the N400 (which is classically associated with retrieval from semantic memory) was maximal for general facts and the LPC (which is classically associated with retrieval from episodic memory) was maximal for unique events. For both ERP components, the two personal semantic conditions (i.e., autobiographical facts and repeated events) systematically differed from semantic memory. In addition, N400 amplitudes also differentiated autobiographical facts from unique events. Autobiographical facts and repeated events did not differ significantly from each other but their corresponding scalp distributions differed from those associated with general facts. Our results suggest that the neural correlates of personal semantics can be distinguished from those of semantic and episodic memory, and may provide clues as to how unique events are transformed to semantic memory. Copyright © 2015 Elsevier

  2. UML 2 Semantics and Applications

    CERN Document Server

    Lano, Kevin

    2009-01-01

    A coherent and integrated account of the leading UML 2 semantics work and the practical applications of UML semantics development With contributions from leading experts in the field, the book begins with an introduction to UML and goes on to offer in-depth and up-to-date coverage of: The role of semantics Considerations and rationale for a UML system model Definition of the UML system model UML descriptive semantics Axiomatic semantics of UML class diagrams The object constraint language Axiomatic semantics of state machines A coalgebraic semantic framework for reasoning about interaction des

  3. Categorizing words through semantic memory navigation

    Science.gov (United States)

    Borge-Holthoefer, J.; Arenas, A.

    2010-03-01

    Semantic memory is the cognitive system devoted to storage and retrieval of conceptual knowledge. Empirical data indicate that semantic memory is organized in a network structure. Everyday experience shows that word search and retrieval processes provide fluent and coherent speech, i.e. are efficient. This implies either that semantic memory encodes, besides thousands of words, different kind of links for different relationships (introducing greater complexity and storage costs), or that the structure evolves facilitating the differentiation between long-lasting semantic relations from incidental, phenomenological ones. Assuming the latter possibility, we explore a mechanism to disentangle the underlying semantic backbone which comprises conceptual structure (extraction of categorical relations between pairs of words), from the rest of information present in the structure. To this end, we first present and characterize an empirical data set modeled as a network, then we simulate a stochastic cognitive navigation on this topology. We schematize this latter process as uncorrelated random walks from node to node, which converge to a feature vectors network. By doing so we both introduce a novel mechanism for information retrieval, and point at the problem of category formation in close connection to linguistic and non-linguistic experience.

  4. Lack of semantic priming effects in famous person recognition in Mild Cognitive Impairment.

    Science.gov (United States)

    Brambati, Simona M; Peters, Frédéric; Belleville, Sylvie; Joubert, Sven

    2012-04-01

    Growing evidence indicates that individuals with Mild Cognitive Impairment (MCI) manifest semantic deficits that are often more severe for items that are characterized by a unique semantic and lexical association, such as famous people and famous buildings, than common concepts, such as objects. However, it is still controversial whether the semantic deficits observed in MCI are determined by a degradation of semantic information or by a deficit in intentional access to semantic knowledge. Here we used a semantic priming task in order to assess the integrity of the semantic system without requiring explicit access to this system. This paradigm may provide new insights in clarifying the nature of the semantic deficits in MCI. We assessed the semantic and repetition priming effect in 13 individuals with MCI and 13 age-matched controls who engaged in a familiarity judgment task of famous names. In the semantic priming condition, the prime was the name of a member of the same occupation category as the target (Tom Cruise-Brad Pitt), while in the repetition priming condition the prime was the same name as the target (Charlie Chaplin-Charlie Chaplin). The results showed a defective priming effect in MCI in the semantic but not in the repetition priming condition. Specifically, when compared to controls, MCI patients did not show a facilitation effect in responding to the same occupation prime-target pairs, but they showed an equivalent facilitation effect when the target was the same name as the prime. The present results provide support to the hypothesis that the semantic impairments observed in MCI cannot be uniquely ascribed to a deficit in intentional access to semantic information. Instead, these findings point to the semantic nature of these deficits and, in particular, to a degraded representation of semantic information concerning famous people. Copyright © 2011 Elsevier Srl. All rights reserved.

  5. Acoustic and semantic interference effects in words and pictures.

    Science.gov (United States)

    Dhawan, M; Pellegrino, J W

    1977-05-01

    Interference effects for pictures and words were investigated using a probe-recall task. Word stimuli showed acoustic interference effects for items at the end of the list and semantic interference effects for items at the beginning of the list, similar to results of Kintsch and Buschke (1969). Picture stimuli showed large semantic interference effects at all list positions with smaller acoustic interference effects. The results were related to latency data on picture-word processing and interpreted in terms of the differential order, probability, and/or speed of access to acoustic and semantic levels of processing. A levels of processing explanation of picture-word retention differences was related to dual coding theory. Both theoretical positions converge on an explanation of picture-word retention differences as a function of the relative capacity for semantic or associative processing.

  6. Imaging dementias

    Energy Technology Data Exchange (ETDEWEB)

    Savoiardo, M.; Grisoli, M. [Dept. of Neuroradiology, Istituto Nazionale Neurologico, Milan (Italy)

    2001-03-01

    Dementia is the progressive loss of intellectual functions due to involvement of cortical or subcortical areas. Specific involvement of certain brain areas in the different diseases leads to impairment of different functions, e. g., memory, language, visuospatial abilities, and behavior. Magnetic resonance imaging and other neuroradiological studies may indicate which structures are mainly or selectively involved in a demented patient, thus allowing clinical-radiological correlations. Clinical presentation and evolution of the disease, supported by imaging studies, may lead to a highly probable diagnosis. The most common disorders, or the most relevant from the neuroradiological point of view, such as Alzheimer's disease, frontotemporal dementia, vascular dementias, dementia associated with parkinsonism, Huntington's disease, Creutzfeldt-Jakob disease, and normal-pressure hydrocephalus, are briefly discussed. (orig.)

  7. Imaging dementias

    International Nuclear Information System (INIS)

    Savoiardo, M.; Grisoli, M.

    2001-01-01

    Dementia is the progressive loss of intellectual functions due to involvement of cortical or subcortical areas. Specific involvement of certain brain areas in the different diseases leads to impairment of different functions, e. g., memory, language, visuospatial abilities, and behavior. Magnetic resonance imaging and other neuroradiological studies may indicate which structures are mainly or selectively involved in a demented patient, thus allowing clinical-radiological correlations. Clinical presentation and evolution of the disease, supported by imaging studies, may lead to a highly probable diagnosis. The most common disorders, or the most relevant from the neuroradiological point of view, such as Alzheimer's disease, frontotemporal dementia, vascular dementias, dementia associated with parkinsonism, Huntington's disease, Creutzfeldt-Jakob disease, and normal-pressure hydrocephalus, are briefly discussed. (orig.)

  8. Semantic graphs and associative memories

    Science.gov (United States)

    Pomi, Andrés; Mizraji, Eduardo

    2004-12-01

    Graphs have been increasingly utilized in the characterization of complex networks from diverse origins, including different kinds of semantic networks. Human memories are associative and are known to support complex semantic nets; these nets are represented by graphs. However, it is not known how the brain can sustain these semantic graphs. The vision of cognitive brain activities, shown by modern functional imaging techniques, assigns renewed value to classical distributed associative memory models. Here we show that these neural network models, also known as correlation matrix memories, naturally support a graph representation of the stored semantic structure. We demonstrate that the adjacency matrix of this graph of associations is just the memory coded with the standard basis of the concept vector space, and that the spectrum of the graph is a code invariant of the memory. As long as the assumptions of the model remain valid this result provides a practical method to predict and modify the evolution of the cognitive dynamics. Also, it could provide us with a way to comprehend how individual brains that map the external reality, almost surely with different particular vector representations, are nevertheless able to communicate and share a common knowledge of the world. We finish presenting adaptive association graphs, an extension of the model that makes use of the tensor product, which provides a solution to the known problem of branching in semantic nets.

  9. When the Wedding March becomes sad: Semantic memory impairment for music in the semantic variant of primary progressive aphasia.

    Science.gov (United States)

    Macoir, Joël; Berubé-Lalancette, Sarah; Wilson, Maximiliano A; Laforce, Robert; Hudon, Carol; Gravel, Pierre; Potvin, Olivier; Duchesne, Simon; Monetta, Laura

    2016-12-01

    Music can induce particular emotions and activate semantic knowledge. In the semantic variant of primary progressive aphasia (svPPA), semantic memory is impaired as a result of anterior temporal lobe (ATL) atrophy. Semantics is responsible for the encoding and retrieval of factual knowledge about music, including associative and emotional attributes. In the present study, we report the performance of two individuals with svPPA in three experiments. NG with bilateral ATL atrophy and ND with atrophy largely restricted to the left ATL. Experiment 1 assessed the recognition of musical excerpts and both patients were unimpaired. Experiment 2 studied the emotions conveyed by music and only NG showed impaired performance. Experiment 3 tested the association of semantic concepts to musical excerpts and both patients were impaired. These results suggest that the right ATL seems essential for the recognition of emotions conveyed by music and that the left ATL is involved in binding music to semantics. They are in line with the notion that the ATLs are devoted to the binding of different modality-specific properties and suggest that they are also differentially involved in the processing of factual and emotional knowledge associated with music.

  10. Clinical and neuroimage findings of dementia with lewy bodies

    International Nuclear Information System (INIS)

    Kang, Do Young; Park, Kyung Won; Kim, Jae Woo

    2002-01-01

    Dementia with lewy bodies (DLB) is the second common degenerative dementia and has several characteristics including fluctuating cognition, visual hallucination and Parkinsonism. We investigated clinical manifestations and neuroimaging findings in DLB patients. Ten probable DLB patients were included in this study. Brain MRI, Tc-99m HMPAO brain perfusion SPECT and I-123 IPT SPECT were performed. All patients were men and mean age of onset was 64.2 years (range from 54 to 80). All had fluctuating cognition and Parkinsonism, and 8 had visual hallucination. Dementia preceded Parkinsonism in 3 patients. Fluctuation of K-MMSE ranges from 3 to 8 points. Rest tremor was seen in 5 patients. Brain MRI showed cortical atrophy in all patients. Tc-99m brain perfusion SPECT showed hypoperfusion in occipital area as well as fronto-temporo-parietal areas. I-123 IPT SPECT revealed reduced uptake comparable to Parkinson's disease in the striatum. DLB should be first considered as one of possible diagnosis in patients showing dementia in the early stage of Parkinsonism. Hypoperfusion in the occipital area was thought to be a characteristic finding in DLB and to be helpful in differentiating DLB from other degenerative dementias

  11. Reflect: a practical approach to web semantics

    DEFF Research Database (Denmark)

    O'Donoghue, S.I.; Horn, Heiko; Pafilisa, E.

    2010-01-01

    To date, adding semantic capabilities to web content usually requires considerable server-side re-engineering, thus only a tiny fraction of all web content currently has semantic annotations. Recently, we announced Reflect (http://reflect.ws), a free service that takes a more practical approach......: Reflect uses augmented browsing to allow end-users to add systematic semantic annotations to any web-page in real-time, typically within seconds. In this paper we describe the tagging process in detail and show how further entity types can be added to Reflect; we also describe how publishers and content...... web technologies....

  12. Depression and dementia: cause, consequence or coincidence?

    Science.gov (United States)

    Bennett, Sophia; Thomas, Alan J

    2014-10-01

    The relationship between depression and dementia is complex and still not well understood. A number of different views exist regarding how the two conditions are linked as well as the underlying neurobiological mechanisms at work. This narrative review examined longitudinal and cross sectional studies in the existing literature and determined the evidence supporting depression being a risk factor, a prodrome, a consequence, or an independent comorbidity in dementia. Overall there is convincing evidence to support both the notion that early life depression can act as a risk factor for later life dementia, and that later life depression can be seen as a prodrome to dementia. There is also evidence to support both conditions showing similar neurobiological changes, particularly white matter disease, either indicating shared risk factors or a shared pattern of neuronal damage. These findings highlight the need to examine if effective treatment of depressive episodes has any effect in reducing the prevalence of dementia, as well as clinicians being vigilant for late life depression indicating the incipient development of dementia, and therefore carefully following up these individuals for future cognitive impairment. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. The structure of semantic person memory: evidence from semantic priming in person recognition.

    Science.gov (United States)

    Wiese, Holger

    2011-11-01

    This paper reviews research on the structure of semantic person memory as examined with semantic priming. In this experimental paradigm, a familiarity decision on a target face or written name is usually faster when it is preceded by a related as compared to an unrelated prime. This effect has been shown to be relatively short lived and susceptible to interfering items. Moreover, semantic priming can cross stimulus domains, such that a written name can prime a target face and vice versa. However, it remains controversial whether representations of people are stored in associative networks based on co-occurrence, or in more abstract semantic categories. In line with prominent cognitive models of face recognition, which explain semantic priming by shared semantic information between prime and target, recent research demonstrated that priming could be obtained from purely categorically related, non-associated prime/target pairs. Although strategic processes, such as expectancy and retrospective matching likely contribute, there is also evidence for a non-strategic contribution to priming, presumably related to spreading activation. Finally, a semantic priming effect has been demonstrated in the N400 event-related potential (ERP) component, which may reflect facilitated access to semantic information. It is concluded that categorical relatedness is one organizing principle of semantic person memory. ©2011 The British Psychological Society.

  14. Meinongian Semantics and Artificial Intelligence

    Directory of Open Access Journals (Sweden)

    William J. Rapaport

    2013-12-01

    Full Text Available This essay describes computational semantic networks for a philosophical audience and surveys several approaches to semantic-network semantics. In particular, propositional semantic networks (exemplified by SNePS are discussed; it is argued that only a fully intensional, Meinongian semantics is appropriate for them; and several Meinongian systems are presented.

  15. Depression-dementia medius: between depression and the manifestation of dementia symptoms.

    Science.gov (United States)

    Kobayashi, Toshiyuki; Kato, Satoshi

    2011-09-01

    Depression and dementia, among the most common conditions in clinical practice, sometimes coexist, sometimes succeed each other, and often confuse clinicians. In the present paper, the clinical concept of 'depression-dementia medius' (which includes pseudodementia and depression in Alzheimer's disease as exemplars) is proposed, in reference to Janet's concept of psychological tension. Because psychosomatically complex human lives are always in a state of dynamic equilibrium, it seems sensible to propose that pseudodementia and depression in Alzheimer's disease are located within a spectrum extending from depression without dementia symptoms to dementia without depression. From the Janetian viewpoint, pseudodementia is regarded as uncovered latent dementia as a result of reduced psychological tension. Dementia is more than a fixed progressive condition under this view, and is a manifestation of dynamic mental activities. Characterizing these entities through perspectives such as psychological tension may yield deep insights in clinical practice. © 2011 The Authors. Psychogeriatrics © 2011 Japanese Psychogeriatric Society.

  16. Geospatial Semantics and the Semantic Web

    CERN Document Server

    Ashish, Naveen

    2011-01-01

    The availability of geographic and geospatial information and services, especially on the open Web has become abundant in the last several years with the proliferation of online maps, geo-coding services, geospatial Web services and geospatially enabled applications. The need for geospatial reasoning has significantly increased in many everyday applications including personal digital assistants, Web search applications, local aware mobile services, specialized systems for emergency response, medical triaging, intelligence analysis and more. Geospatial Semantics and the Semantic Web: Foundation

  17. Automaticity Revisited: When Print Doesn't Activate Semantics

    Directory of Open Access Journals (Sweden)

    Elsa Magdalena Labuschagne

    2015-02-01

    Full Text Available It is widely accepted that the presentation of a printed word automatically triggers processing that ends with full semantic activation. This processing, among other characteristics, is held to occur without intention, and cannot be stopped. The results of the present experiment show that this account is problematic in the context of a variant of the Stroop paradigm. Subjects named the print color of words that were either neutral or semantically related to color. When the letters were all colored, all spatially cued, and the spaces between letters were filled with characters from the top of the keyboard (i.e., 4, #, 5, %, 6, and *, color naming yielded a semantically based Stroop effect and a semantically based negative priming effect. In contrast, the same items yielded neither a semantic Stroop effect nor a negative priming effect when a single target letter was uniquely colored and spatially cued. These findings undermine the widespread view that lexical-semantic activation in word reading is automatic in the sense that it occurs without intention and cannot be derailed.

  18. Early-Onset Dementia

    DEFF Research Database (Denmark)

    Konijnenberg, Elles; Fereshtehnejad, Seyed-Mohammad; Kate, Mara Ten

    2017-01-01

    BACKGROUND: Early-onset dementia (EOD) is a rare condition, with an often atypical clinical presentation, and it may therefore be challenging to diagnose. Specialized memory clinics vary in the type of patients seen, diagnostic procedures applied, and the pharmacological treatment given. The aim...... of this study was to investigate quality-of-care indicators in subjects with EOD from 3 tertiary memory clinics in 3 European countries. METHODS: We included 1325 newly diagnosed EOD patients, ages 65 years or younger, between January 1, 2007 and December 31, 2013, from the Danish Dementia Registry...... (Rigshospitalet, Copenhagen), the Swedish Dementia Registry ("SveDem", Karolinska University Hospital, Stockholm), and the Amsterdam Dementia Cohort (VU University Medical Center). RESULTS: The frequency of EOD among all dementia patients was significantly lower in Copenhagen (410, 20%) and Stockholm (284, 21...

  19. Antidepressants and dementia

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Søndergård, Lars; Forman, Julie Lyng

    2009-01-01

    BACKGROUND: It has been suggested that antidepressants may have neuroprotective abilities but it has newer been investigated lately whether treatment with antidepressants reduces the risk of dementia. METHOD: Linkage of registers of all prescribed antidepressants and diagnoses of dementia...... in Denmark during a period from 1995 to 2005. RESULTS: Persons who purchased antidepressants once (N=687,552) had an increased rate of dementia compared to persons unexposed to antidepressants (N=779,831). Nevertheless, the rate of dementia changed over time; thus during the initial prescription periods...... the rate increased with the number of prescriptions but continued long-term antidepressants treatment was associated with a reduction in the rate of dementia, however, not to the same level as the rate for the general population. This pattern was found for all classes of antidepressants (SSRIs, newer non...

  20. The Association between Hypertension and Dementia in the Elderly

    Directory of Open Access Journals (Sweden)

    Michiya Igase

    2012-01-01

    Full Text Available Hypertension (HT and dementia are common disorders in the elderly. HT in the elderly is associated with increased occurrence rates of dementia including Alzheimer's disease (AD and vascular dementia (VaD. In connection to this, some studies have suggested that HT in old age correlates with the pathogenesis of dementia. Since HT is potentially reversible, a number of randomized trials have examined whether antihypertensive treatment may help in preventing dementia occurrence. We review five studies, all using subjects 60 years or older, which investigated different antihypertensive pharmacological treatments. Data from two trials (Syst-Eur, PROGRESS open the way toward the prevention of dementia (AD or VaD by antihypertensive treatments. In the Syst-Eur study, with the dihydropyridine calcium antagonists, a reduction in both types of dementia was demonstrated (risk reduction 55%. The PROGRESS study showed that the use of angiotensin-converting enzyme inhibitors (ACEIs, with or without diuretics, resulted in decrease incidence of stroke-related dementia (risk reduction 19%, but dementia without stroke was not reduced. In contrast, the SHEP trial, treatment with a chlorthalidone-based antihypertensive regimen, did not significantly reduced the incidence of dementia. The SCOPE study (candesartan or hydrochlorothiazide versus placebo and the HYVET-COG study (indapamide or perindopril versus placebo found no significant difference between the active treatment and placebo group on the incidence of dementia. We found conflicting results regarding treatment benefits in dementia prevention. Recent clinical trials and studies on animal models suggest that blockades of RAS system could have reduced cognitive decline seen in Alzheimer's disease and vascular dementia. Future trials primarily designed to investigate the effects of antihypertensive agents on impaired cognition are needed.

  1. Mild cognitive impairment as a risk factor for Parkinson's disease dementia.

    Science.gov (United States)

    Hoogland, Jeroen; Boel, Judith A; de Bie, Rob M A; Geskus, Ronald B; Schmand, Ben A; Dalrymple-Alford, John C; Marras, Connie; Adler, Charles H; Goldman, Jennifer G; Tröster, Alexander I; Burn, David J; Litvan, Irene; Geurtsen, Gert J

    2017-07-01

    The International Parkinson and Movement Disorder Society criteria for mild cognitive impairment in PD were recently formulated. The aim of this international study was to evaluate the predictive validity of the comprehensive (level II) version of these criteria by assessment of their contribution to the hazard of PD dementia. Individual patient data were selected from four separate studies on cognition in PD that provided information on demographics, motor examination, depression, neuropsychological examination suitable for application of level II criteria, and longitudinal follow-up for conversion to dementia. Survival analysis evaluated the predictive value of level II criteria for cognitive decline toward dementia as expressed by the relative hazard of dementia. A total of 467 patients were included. The analyses showed a clear contribution of impairment according to level II mild cognitive impairment criteria, age, and severity of PD motor symptoms to the hazard of dementia. There was a trend of increasing hazard of dementia with declining neuropsychological performance. This is the first large international study evaluating the predictive validity of level II mild cognitive impairment criteria for PD. The results showed a clear and unique contribution of classification according to level II criteria to the hazard of PD dementia. This finding supports their predictive validity and shows that they contribute important new information on the hazard of dementia, beyond known demographic and PD-specific factors of influence. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

  2. Knowledge represented using RDF semantic network in the concept of semantic web

    Energy Technology Data Exchange (ETDEWEB)

    Lukasova, A., E-mail: alena.lukasova@osu.cz; Vajgl, M., E-mail: marek.vajgl@osu.cz; Zacek, M., E-mail: martin.zacek@osu.cz [Department of Informatics and Computers, Faculty of Science, University of Ostrava 30. dubna 22, 701 03 Ostrava, Czech Republic http://prf.osu.eu/kip/ (Czech Republic)

    2016-06-08

    The RDF(S) model has been declared as the basic model to capture knowledge of the semantic web. It provides a common and flexible way to decompose composed knowledge to elementary statements, which can be represented by RDF triples or by RDF graph vectors. From the logical point of view, elements of knowledge can be expressed using at most binary predicates, which can be converted to RDF-triples or graph vectors. However, it is not able to capture implicit knowledge representable by logical formulas. This contribution shows how existing approaches (semantic networks and clausal form logic) can be combined together with RDF to obtain RDF-compatible system with ability to represent implicit knowledge and inference over knowledge base.

  3. Knowledge represented using RDF semantic network in the concept of semantic web

    International Nuclear Information System (INIS)

    Lukasova, A.; Vajgl, M.; Zacek, M.

    2016-01-01

    The RDF(S) model has been declared as the basic model to capture knowledge of the semantic web. It provides a common and flexible way to decompose composed knowledge to elementary statements, which can be represented by RDF triples or by RDF graph vectors. From the logical point of view, elements of knowledge can be expressed using at most binary predicates, which can be converted to RDF-triples or graph vectors. However, it is not able to capture implicit knowledge representable by logical formulas. This contribution shows how existing approaches (semantic networks and clausal form logic) can be combined together with RDF to obtain RDF-compatible system with ability to represent implicit knowledge and inference over knowledge base.

  4. Distinct perfusion patterns in Alzheimer's disease, frontotemporal dementia and dementia with Lewy bodies

    International Nuclear Information System (INIS)

    Binnewijzend, Maja A.A.; Wattjes, Mike P.; Berckel, Bart N.M. van; Barkhof, Frederik; Kuijer, Joost P.A.; Flier, Wiesje M. van der; Benedictus, Marije R.; Moeller, Christiane M.; Pijnenburg, Yolande A.L.; Lemstra, Afina W.; Prins, Niels D.; Scheltens, Philip

    2014-01-01

    To compare pseudo-continuous arterial spin-labelled (PCASL) magnetic resonance imaging (MRI) measured quantitative cerebral blood flow (CBF) of patients with frontotemporal dementia (FTD), dementia with Lewy Bodies (DLB), Alzheimer's disease (AD) and controls, in a region of interest (ROI) and voxel-wise fashion. We analysed whole-brain 3D fast-spin-echo PCASL images of 20 FTD patients, 14 DLB patients, 48 AD patients and 50 controls from the Amsterdam Dementia Cohort. Regional CBF patterns were compared using analyses of variance for repeated measures. Permutation tests were used for voxel-wise comparisons. Analyses were performed using uncorrected and partial volume corrected (PVC) maps. All analyses were corrected for age and sex. There was an interaction between diagnosis and region (p < 0.001), implying differences in regional CBF changes between diagnostic groups. In AD patients, CBF was decreased in all supratentorial regions, most prominently so in the posterior regions. DLB patients showed lowest CBF values throughout the brain, but temporal CBF was preserved. Supratentorial PVC cortical CBF values were lowest in the frontal lobes in FTD patients, and in the temporal lobes in AD patients. Patients with AD, FTD and DLB display distinct patterns of quantitative regional CBF changes. 3D-PCASL may provide additional value in the workup of dementia patients. (orig.)

  5. Knowledge of Dementia: Do family members understand dementia as a terminal condition?

    Science.gov (United States)

    Andrews, Sharon; McInerney, Fran; Toye, Christine; Parkinson, Camillus-Anthony; Robinson, Andrew

    2017-07-01

    Current research identifies advanced dementia to be the terminal phase of this progressive and incurable condition. However, there has been relatively little investigation into how family members of people with advanced dementia understand their relative's condition. In this article, we report on semi-structured interviews with 10 family members of people with advanced dementia, in a residential aged care facility. Using a qualitative, descriptive design, we explored family members' understandings of dementia, whether they were aware that it was a terminal condition, and the ways they developed their understandings. Findings revealed that the majority of family members could not recognize the terminal nature of dementia. Relying on predominantly lay understandings, they had little access to formal information and most failed to conceptualize a connection between dementia and death. Moreover, family members engaged in limited dialogue with aged care staff about such issues, despite their relatives being in an advanced stage of the disease. Findings from our study suggest that how family members understand their relative's condition requires greater attention. The development of staff/family partnerships that promote shared communication about dementia and dying may enhance family members' understandings of the dementia trajectory and the types of decisions they may be faced with during the more advanced stages of the disease.

  6. Phytosterols and Dementia.

    Science.gov (United States)

    Shuang, Rong; Rui, Xu; Wenfang, Li

    2016-12-01

    As the aging of the world's population is becoming increasingly serious, dementia-related diseases have become a hot topic in public health research. In recent years, human epidemiological studies have focused on lipid metabolism disorders and dementia. The efficacy of phytosterol intake as a cholesterol-lowering agent has been demonstrated. Phytosterols directly serve as ligands of the nuclear receptors, peroxisome proliferator-activated receptors (PPARs), activating Sirtuin 1 (SIRT-1), which are involved in the regulation of lipid metabolism and the pathogenesis of dementia. Moreover, phytosterols mediate cell and membrane cholesterol efflux or beta amyloid (Aβ) metabolism, which have preventative and therapeutic effects on dementia. Additionally, incorporation of plant sterols in lipid rafts can effectively reduce dietary fat and alter the dietary composition of fiber, fat and cholesterol to regulate appetite and calories. Overall, the objectives of this review are to explore whether phytosterols are a potentially effective target for the prevention of dementia and to discuss a possible molecular mechanism by which phytosterols play a role in the pathogenesis of dementia via the PPARs-SIRT-1 pathway.

  7. Couples with dementia: Positioning the 'we'.

    Science.gov (United States)

    Hydén, Lars-Christer; Nilsson, Elin

    2015-11-01

    The aim of this article is to investigate how spouses in couples with dementia position themselves in relation to each other by analysing their use of pronouns, especially the we. The study uses joint interviews with 11 couples. Based on a quantitative analysis of pronoun use, it is argued that the pronoun we is used by all the spouses; however, it is used less frequently by the spouses with dementia in comparison with healthy spouses. A qualitative analysis of the use of the pronoun we shows that the spouses position, experience and consider themselves as a couple and that they position and experience themselves as individuals in relation to the couple. One of the challenges for couples with dementia is to be able to retain a we in face of the progression of the dementia disease. By positioning themselves in various ways, the spouses establish and negotiate quite a complex and emotionally charged web of relationships. © The Author(s) 2013.

  8. Activation of semantic information at the sublexical level during handwriting production: Evidence from inhibition effects of Chinese semantic radicals in the picture-word interference paradigm.

    Science.gov (United States)

    Chen, Xuqian; Liao, Yuanlan; Chen, Xianzhe

    2017-08-01

    Using a non-alphabetic language (e.g., Chinese), the present study tested a novel view that semantic information at the sublexical level should be activated during handwriting production. Over 80% of Chinese characters are phonograms, in which semantic radicals represent category information (e.g., 'chair,' 'peach,' 'orange' are related to plants) while phonetic radicals represent phonetic information (e.g., 'wolf,' 'brightness,' 'male,' are all pronounced /lang/). Under different semantic category conditions at the lexical level (semantically related in Experiment 1; semantically unrelated in Experiment 2), the orthographic relatedness and semantic relatedness of semantic radicals in the picture name and its distractor were manipulated under different SOAs (i.e., stimulus onset asynchrony, the interval between the onset of the picture and the onset of the interference word). Two questions were addressed: (1) Is it possible that semantic information could be activated in the sublexical level conditions? (2) How are semantic and orthographic information dynamically accessed in word production? Results showed that both orthographic and semantic information were activated under the present picture-word interference paradigm, dynamically under different SOAs, which supported our view that discussions on semantic processes in the writing modality should be extended to the sublexical level. The current findings provide possibility for building new orthography-phonology-semantics models in writing. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  9. Montague semantics

    NARCIS (Netherlands)

    Janssen, T.M.V.

    2012-01-01

    Montague semantics is a theory of natural language semantics and of its relation with syntax. It was originally developed by the logician Richard Montague (1930-1971) and subsequently modified and extended by linguists, philosophers, and logicians. The most important features of the theory are its

  10. From Data to Semantic Information

    Directory of Open Access Journals (Sweden)

    Luciano Floridi

    2003-06-01

    Full Text Available Abstract: There is no consensus yet on the definition of semantic information. This paper contributes to the current debate by criticising and revising the Standard Definition of semantic Information (SDI as meaningful data, in favour of the Dretske-Grice approach: meaningful and well-formed data constitute semantic information only if they also qualify as contingently truthful. After a brief introduction, SDI is criticised for providing necessary but insufficient conditions for the definition of semantic information. SDI is incorrect because truth-values do not supervene on semantic information, and misinformation (that is, false semantic information is not a type of semantic information, but pseudo-information, that is not semantic information at all. This is shown by arguing that none of the reasons for interpreting misinformation as a type of semantic information is convincing, whilst there are compelling reasons to treat it as pseudo-information. As a consequence, SDI is revised to include a necessary truth-condition. The last section summarises the main results of the paper and indicates the important implications of the revised definition for the analysis of the deflationary theories of truth, the standard definition of knowledge and the classic, quantitative theory of semantic information.

  11. Health Policy and Dementia.

    Science.gov (United States)

    Powell, Tia

    2018-02-01

    The anticipated number of persons with dementia continues to grow, and the US has insufficiently planned to provide and pay for care for this large population. A number of significant clinical trials aiming to prevent or cure dementia, including Alzheimer's disease, have not demonstrated success. Because of the lack of efficacious treatments, and the fact that brain changes associated with dementia may begin decades before symptoms, we can predict that efforts to cure or prevent dementia will not succeed in time for millions of people in the baby boomer generation. Because of the anticipated increase in people suffering with dementia in the coming years, US health policy must address major gaps in how to provide and pay for dementia care. Reliance on Medicaid and Medicare as currently structured will not sustain the necessary care, nor can families alone provide all necessary dementia care. Innovative forms of providing long-term care and paying for it are crucially needed.

  12. Semantic similarity between ontologies at different scales

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qingpeng; Haglin, David J.

    2016-04-01

    In the past decade, existing and new knowledge and datasets has been encoded in different ontologies for semantic web and biomedical research. The size of ontologies is often very large in terms of number of concepts and relationships, which makes the analysis of ontologies and the represented knowledge graph computational and time consuming. As the ontologies of various semantic web and biomedical applications usually show explicit hierarchical structures, it is interesting to explore the trade-offs between ontological scales and preservation/precision of results when we analyze ontologies. This paper presents the first effort of examining the capability of this idea via studying the relationship between scaling biomedical ontologies at different levels and the semantic similarity values. We evaluate the semantic similarity between three Gene Ontology slims (Plant, Yeast, and Candida, among which the latter two belong to the same kingdom—Fungi) using four popular measures commonly applied to biomedical ontologies (Resnik, Lin, Jiang-Conrath, and SimRel). The results of this study demonstrate that with proper selection of scaling levels and similarity measures, we can significantly reduce the size of ontologies without losing substantial detail. In particular, the performance of Jiang-Conrath and Lin are more reliable and stable than that of the other two in this experiment, as proven by (a) consistently showing that Yeast and Candida are more similar (as compared to Plant) at different scales, and (b) small deviations of the similarity values after excluding a majority of nodes from several lower scales. This study provides a deeper understanding of the application of semantic similarity to biomedical ontologies, and shed light on how to choose appropriate semantic similarity measures for biomedical engineering.

  13. Foundations of semantic web technologies

    CERN Document Server

    Hitzler, Pascal; Rudolph, Sebastian

    2009-01-01

    The Quest for Semantics Building Models Calculating with Knowledge Exchanging Information Semanic Web Technologies RESOURCE DESCRIPTION LANGUAGE (RDF)Simple Ontologies in RDF and RDF SchemaIntroduction to RDF Syntax for RDF Advanced Features Simple Ontologies in RDF Schema Encoding of Special Data Structures An ExampleRDF Formal Semantics Why Semantics? Model-Theoretic Semantics for RDF(S) Syntactic Reasoning with Deduction Rules The Semantic Limits of RDF(S)WEB ONTOLOGY LANGUAGE (OWL) Ontologies in OWL OWL Syntax and Intuitive Semantics OWL Species The Forthcoming OWL 2 StandardOWL Formal Sem

  14. Epidemiology of early-onset dementia: a review of the literature

    Science.gov (United States)

    Vieira, Renata Teles; Caixeta, Leonardo; Machado, Sergio; Silva, Adriana Cardoso; Nardi, Antonio Egidio; Arias-Carrión, Oscar; Carta, Mauro Giovanni

    2013-01-01

    Presenile Dementia or Early Onset Dementia (EOD) is a public health problem, it differs from Senile Dementia, and encloses a significant number of cases; nevertheless, it is still poorly understood and underdiagnosed. This study aims to review the prevalence and etiology of EOD, comparing EOD with Senile Dementia, as well as to show the main causes of EOD and their prevalence in population and non-population based studies. The computer-supported search used the following databases: Pubmed/Medline, ISI Web of Knowledge and Scielo. The search terms were alcohol-associated dementia, Alzheimer’s disease, dementia, Creutzfeldt-jakob disease, dementia with lewy bodies, early onset dementia, frontotemporal lobar degeneration, Huntington’s disease, mixed dementia, neurodegenerative disorders, Parkinson’s disease dementia, presenile dementia, traumatic brain injury, vascular dementia. Only papers published in English and conducted from 1985 up to 2012 were preferentially reviewed. Neurodegenerative diseases are the most common etiologies seen in EOD. Among the general population, the prevalence of EOD was found to range between 0 to 700 per 100.000 habitants in groups of 25-64 years old, with an increasing incidence with age. The progression of EOD was found to range between 8.3 to 22.8 new cases per 100.000 in those aged under 65 years. Alzheimer's disease (AD) is the major etiology, followed by Vascular Dementia (VaD) and Frontotemporal Lobar Degeneration (FTLD). A larger number of epidemiological studies to elucidate how environmental issues contribute to EOD are necessary, thus, we can collaborate in the planning and prevention of services toward dementia patients. PMID:23878613

  15. Odor identification: perceptual and semantic dimensions.

    Science.gov (United States)

    Cain, W S; de Wijk, R; Lulejian, C; Schiet, F; See, L C

    1998-06-01

    Five studies explored identification of odors as an aspect of semantic memory. All dealt in one way or another with the accessibility of acquired olfactory information. The first study examined stability and showed that, consistent with personal reports, people can fail to identify an odor one day yet succeed another. Failure turned more commonly to success than vice versa, and once success occurred it tended to recur. Confidence ratings implied that subjects generally knew the quality of their answers. Even incorrect names, though, often carried considerable information which sometimes reflected a semantic and sometimes a perceptual source of errors. The second study showed that profiling odors via the American Society of Testing and Materials list of attributes, an exercise in depth of processing, effected no increment in the identifiability/accessibility beyond an unelaborated second attempt at retrieval. The third study showed that subjects had only a weak ability to predict the relative recognizability of odors they had failed to identify. Whereas the strength of the feeling that they would 'know' an answer if offered choices did not associate significantly with performance for odors, it did for trivia questions. The fourth study demonstrated an association between ability to discriminate among one set of odors and to identify another, but this emerged only after subjects had received feedback about identity, which essentially changed the task to one of recognition and effectively stabilized access. The fifth study illustrated that feedback improves performance dramatically only for odors involved with it, but that mere retrieval leads to some improvement. The studies suggest a research agenda that could include supplemental use of confidence judgments both retrospectively and prospectively in the same subjects to indicate the amount of accessible semantic information; use of second and third guesses to examine subjects' simultaneously held hypotheses about

  16. A Semantic Prosody Analysis of Three Adjective Synonymous Pairs in COCA

    Science.gov (United States)

    Hu, H. C. Marcella

    2015-01-01

    Over the past two decades the concept of semantic prosody has attracted considerable research interest since Sinclair (1991) observed that "many uses of words and phrases show a tendency to occur in a certain semantic environment" (p. 112). Sinclair (2003) also noted that semantic prosody conveys its pragmatic meaning and attitudinal…

  17. A Complex Network Approach to Distributional Semantic Models.

    Directory of Open Access Journals (Sweden)

    Akira Utsumi

    Full Text Available A number of studies on network analysis have focused on language networks based on free word association, which reflects human lexical knowledge, and have demonstrated the small-world and scale-free properties in the word association network. Nevertheless, there have been very few attempts at applying network analysis to distributional semantic models, despite the fact that these models have been studied extensively as computational or cognitive models of human lexical knowledge. In this paper, we analyze three network properties, namely, small-world, scale-free, and hierarchical properties, of semantic networks created by distributional semantic models. We demonstrate that the created networks generally exhibit the same properties as word association networks. In particular, we show that the distribution of the number of connections in these networks follows the truncated power law, which is also observed in an association network. This indicates that distributional semantic models can provide a plausible model of lexical knowledge. Additionally, the observed differences in the network properties of various implementations of distributional semantic models are consistently explained or predicted by considering the intrinsic semantic features of a word-context matrix and the functions of matrix weighting and smoothing. Furthermore, to simulate a semantic network with the observed network properties, we propose a new growing network model based on the model of Steyvers and Tenenbaum. The idea underlying the proposed model is that both preferential and random attachments are required to reflect different types of semantic relations in network growth process. We demonstrate that this model provides a better explanation of network behaviors generated by distributional semantic models.

  18. A study of expertise effects for products with contradictory semantics

    Directory of Open Access Journals (Sweden)

    Wang Ching-Yi

    2017-01-01

    Full Text Available In the design studies, researchers often use the semantic differential method with bipolar adjectives, such as “modern vs. classical” or “simple vs. complex” when investigating the semantics projected by product forms. However, in design practice, some design examples clearly exhibit the simultaneous use of contradictory meanings in product semantics. For example, retro car evokes nostalgia by borrowing characteristics from classical cars. At the same time it exhibits a modern style. However, most studies measure the product semantics mostly by using subjective measurement. There is lack objective measurement for that. In this research, we examined the results of applying the semantic differential method to measure contradiction in product semantics. The results showed that the distributions of semantic differential ratings for the stimuli with contradictory meanings have higher standard deviations. The sensitivity of semantic recognition may depend on participant expertise. The design experts are trained to be good at visual thinking that could easily identify the contradiction semantics between products. In general, successful embedding of contradictory meanings into product forms are based on simple, typical, and rational forms that can display complex, novel, and perceptual images by adding supplementary elements.

  19. Towards Compatible and Interderivable Semantic Specifications for the Scheme Programming Language, Part II: Reduction Semantics and Abstract Machines

    DEFF Research Database (Denmark)

    Biernacka, Malgorzata; Danvy, Olivier

    2008-01-01

    We present a context-sensitive reduction semantics for a lambda-calculus with explicit substitutions and store and we show that the functional implementation of this small-step semantics mechanically corresponds to that of an abstract machine. This abstract machine is very close to the abstract m...... machine for Core Scheme presented by Clinger at PLDI'98. This lambda-calculus with explicit substitutions and store therefore aptly accounts for Core Scheme....

  20. Montessori-based dementia care.

    Science.gov (United States)

    Cline, Janet

    2006-10-01

    Montessori-based Dementia Care is an approach used in Alzheimer's care that does not involve chemical or physical restraints. This program works by giving the elder with Alzheimer/Dementia a purpose by getting them involved. When staff/families care for a confused Alzheimer/Dementia patient, who is having behaviors, the Montessori program teaches them to look at what is causing the behavior. When assessing the elder to determine what is causing the behavior, the goal is to find the answer, but the answer cannot be dementia. The goal of the program is to bring meaning to the life of an Alzheimer/Dementia elder.

  1. Lewy Body Dementia Diagnosis

    Science.gov (United States)

    ... provide an experienced diagnostic team skilled in Lewy body dementia. A thorough dementia diagnostic evaluation includes physical ... a good way to benefit others with Lewy body dementia. Medications Medications are one of the most ...

  2. Leisure activities, cognition and dementia.

    Science.gov (United States)

    Wang, Hui-Xin; Xu, Weili; Pei, Jin-Jing

    2012-03-01

    Accumulated evidence shows that leisure activities have a positive impact on cognitive function and dementia. This review aimed to systematically summarize the current evidence on this topic taking into account the limitations of the studies and biological plausibility for the underlying mechanisms linking cognition, dementia and leisure activities, with special attention on mental, physical and social activities. We included only longitudinal studies, with a follow-up time of at least 2 years, published in English from 1991 to March 2011 on leisure activities and cognition (n=29) or dementia (n=23) and provided some evidence from intervention studies on the topic. A protective effect of mental activity on cognitive function has been consistently reported in both observational and interventional studies. The association of mental activity with the risk of dementia was robust in observational studies but inconsistent in clinical trials. The protective effect of physical activity on the risk of cognitive decline and dementia has been reported in most observational studies, but has been less evident in interventional studies. Current evidence concerning the beneficial effect of other types of leisure activities on the risk of dementia is still limited and results are inconsistent. For future studies it is imperative that the assessment of leisure activities is standardized, for example, the frequency, intensity, duration and the type of activity; and also that the cognitive test batteries and the definition of cognitive decline are harmonized/standardized. Further, well designed studies with long follow-up times are necessary. This article is part of a Special Issue entitled: Imaging Brain Aging and Neurodegenerative disease. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Autobiographical memories in testimonies of WWII Veterans with dementia

    Directory of Open Access Journals (Sweden)

    Tricia Olea Santos

    2015-04-01

    Full Text Available This study is a continuation of investigations of personal narratives of healthy older adults and those with aphasia. It focuses on autobiographical memories in testimonies of elderly WWII veterans with dementia, with particular emphasis on emotional events that occurred at the time of their memory peak. This study describes how declines in memory affect changes in language in narratives of memorable experiences at the time in old age when life review is typically experienced. Ten WWII veterans with dementia were selected from a larger study of healthy elderly veterans. Participants were between the ages of 86-91 years old, with the majority obtaining higher education. Based on the Arizona Battery for Communication Disorders of Dementia, participants demonstrated dementia of mild-to-moderate severity. Semi-structured interviews were conducted to elicit memorable war experiences. Modifications to the interview were made, such as the use of photos to set the topic and occasional closed-ended questions to facilitate responses. Information was recorded and analyzed in terms of the amount and specificity of linguistic information, overall coherence of narratives, and the evaluations of memorable war experiences. The participants were not able to produce complete narratives; they instead relayed short episodes of their war experiences. Difficulties with semantic and episodic memory were reflected in the reduced length of their stories. Anomia was inherent in these episodes, as evidenced by the absence of specific names, dates and places. Lack of specificity was exhibited in reduced details and the use of nonspecific referents, such as “thing,” “stuff,” “there.” Participants produced coherent short story episodes. Coherence in episodic structure was maintained by the ability to relate events in a temporal sequence. Repetition was a strategy that served essential functions of emphasizing a point and/or clarifying breakdowns in communication

  4. Somatotopic Semantic Priming and Prediction in the Motor System

    Science.gov (United States)

    Grisoni, Luigi; Dreyer, Felix R.; Pulvermüller, Friedemann

    2016-01-01

    The recognition of action-related sounds and words activates motor regions, reflecting the semantic grounding of these symbols in action information; in addition, motor cortex exerts causal influences on sound perception and language comprehension. However, proponents of classic symbolic theories still dispute the role of modality-preferential systems such as the motor cortex in the semantic processing of meaningful stimuli. To clarify whether the motor system carries semantic processes, we investigated neurophysiological indexes of semantic relationships between action-related sounds and words. Event-related potentials revealed that action-related words produced significantly larger stimulus-evoked (Mismatch Negativity-like) and predictive brain responses (Readiness Potentials) when presented in body-part-incongruent sound contexts (e.g., “kiss” in footstep sound context; “kick” in whistle context) than in body-part-congruent contexts, a pattern reminiscent of neurophysiological correlates of semantic priming. Cortical generators of the semantic relatedness effect were localized in areas traditionally associated with semantic memory, including left inferior frontal cortex and temporal pole, and, crucially, in motor areas, where body-part congruency of action sound–word relationships was indexed by a somatotopic pattern of activation. As our results show neurophysiological manifestations of action-semantic priming in the motor cortex, they prove semantic processing in the motor system and thus in a modality-preferential system of the human brain. PMID:26908635

  5. Semantic guidance of eye movements in real-world scenes.

    Science.gov (United States)

    Hwang, Alex D; Wang, Hsueh-Cheng; Pomplun, Marc

    2011-05-25

    The perception of objects in our visual world is influenced by not only their low-level visual features such as shape and color, but also their high-level features such as meaning and semantic relations among them. While it has been shown that low-level features in real-world scenes guide eye movements during scene inspection and search, the influence of semantic similarity among scene objects on eye movements in such situations has not been investigated. Here we study guidance of eye movements by semantic similarity among objects during real-world scene inspection and search. By selecting scenes from the LabelMe object-annotated image database and applying latent semantic analysis (LSA) to the object labels, we generated semantic saliency maps of real-world scenes based on the semantic similarity of scene objects to the currently fixated object or the search target. An ROC analysis of these maps as predictors of subjects' gaze transitions between objects during scene inspection revealed a preference for transitions to objects that were semantically similar to the currently inspected one. Furthermore, during the course of a scene search, subjects' eye movements were progressively guided toward objects that were semantically similar to the search target. These findings demonstrate substantial semantic guidance of eye movements in real-world scenes and show its importance for understanding real-world attentional control. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. The effects of associative and semantic priming in the lexical decision task.

    Science.gov (United States)

    Perea, Manuel; Rosa, Eva

    2002-08-01

    Four lexical decision experiments were conducted to examine under which conditions automatic semantic priming effects can be obtained. Experiments 1 and 2 analyzed associative/semantic effects at several very short stimulus-onset asynchronies (SOAs), whereas Experiments 3 and 4 used a single-presentation paradigm at two response-stimulus intervals (RSIs). Experiment 1 tested associatively related pairs from three semantic categories (synonyms, antonyms, and category coordinates). The results showed reliable associative priming effects at all SOAs. In addition, the correlation between associative strength and magnitude of priming was significant only at the shortest SOA (66 ms). When prime-target pairs were semantically but not associatively related (Experiment 2), reliable priming effects were obtained at SOAs of 83 ms and longer. Using the single-presentation paradigm with a short RSI (200 ms, Experiment 3), the priming effect was equal in size for associative + semantic and for semantic-only pairs (a 21-ms effect). When the RSI was set much longer (1,750 ms, Experiment 4), only the associative + semantic pairs showed a reliable priming effect (23 ms). The results are interpreted in the context of models of semantic memory.

  7. Basic semantics of product sounds

    NARCIS (Netherlands)

    Özcan Vieira, E.; Van Egmond, R.

    2012-01-01

    Product experience is a result of sensory and semantic experiences with product properties. In this paper, we focus on the semantic attributes of product sounds and explore the basic components for product sound related semantics using a semantic differential paradigmand factor analysis. With two

  8. Retrieval from semantic memory.

    NARCIS (Netherlands)

    Noordman-Vonk, Wietske

    1977-01-01

    The present study has been concerned with the retrieval of semantic information. Retrieving semantic information is a fundamental process in almost any kind of cognitive behavior. The introduction presented the main experimental paradigms and results found in the literature on semantic memory as

  9. Towards Universal Semantic Tagging

    NARCIS (Netherlands)

    Abzianidze, Lasha; Bos, Johan

    2017-01-01

    The paper proposes the task of universal semantic tagging---tagging word tokens with language-neutral, semantically informative tags. We argue that the task, with its independent nature, contributes to better semantic analysis for wide-coverage multilingual text. We present the initial version of

  10. Process-oriented semantic web search

    CERN Document Server

    Tran, DT

    2011-01-01

    The book is composed of two main parts. The first part is a general study of Semantic Web Search. The second part specifically focuses on the use of semantics throughout the search process, compiling a big picture of Process-oriented Semantic Web Search from different pieces of work that target specific aspects of the process.In particular, this book provides a rigorous account of the concepts and technologies proposed for searching resources and semantic data on the Semantic Web. To collate the various approaches and to better understand what the notion of Semantic Web Search entails, this bo

  11. Semantic SenseLab: Implementing the vision of the Semantic Web in neuroscience.

    Science.gov (United States)

    Samwald, Matthias; Chen, Huajun; Ruttenberg, Alan; Lim, Ernest; Marenco, Luis; Miller, Perry; Shepherd, Gordon; Cheung, Kei-Hoi

    2010-01-01

    Integrative neuroscience research needs a scalable informatics framework that enables semantic integration of diverse types of neuroscience data. This paper describes the use of the Web Ontology Language (OWL) and other Semantic Web technologies for the representation and integration of molecular-level data provided by several of SenseLab suite of neuroscience databases. Based on the original database structure, we semi-automatically translated the databases into OWL ontologies with manual addition of semantic enrichment. The SenseLab ontologies are extensively linked to other biomedical Semantic Web resources, including the Subcellular Anatomy Ontology, Brain Architecture Management System, the Gene Ontology, BIRNLex and UniProt. The SenseLab ontologies have also been mapped to the Basic Formal Ontology and Relation Ontology, which helps ease interoperability with many other existing and future biomedical ontologies for the Semantic Web. In addition, approaches to representing contradictory research statements are described. The SenseLab ontologies are designed for use on the Semantic Web that enables their integration into a growing collection of biomedical information resources. We demonstrate that our approach can yield significant potential benefits and that the Semantic Web is rapidly becoming mature enough to realize its anticipated promises. The ontologies are available online at http://neuroweb.med.yale.edu/senselab/. 2009 Elsevier B.V. All rights reserved.

  12. Dissociation between implicit and explicit manifestations of awareness in early stage dementia: evidence from the emotional Stroop effect for dementia-related words.

    Science.gov (United States)

    Martyr, Anthony; Clare, Linda; Nelis, Sharon M; Roberts, Judith L; Robinson, Julia U; Roth, Ilona; Markova, Ivana S; Woods, Robert T; Whitaker, Christopher J; Morris, Robin G

    2011-01-01

    To determine whether people with dementia (PwD), and carers of PwD, show a processing bias to dementia-related words in an emotional Stroop task, and if so, whether the presence of such a bias is related to level of explicit awareness of the condition. Seventy-nine people with early stage Alzheimer's disease (AD), vascular or mixed dementia, and their carers, completed an emotional Stroop task. Time taken to colour-name dementia-related and neutral words was compared within and between groups. Additionally, as a comparison, ratings of the awareness of the condition shown by PwD were made on the basis of a detailed interview with each PwD and his/her carer. PwD and carers showed the same level of increase in response times to salient compared to neutral words. In the PwD this effect was unrelated to the degree of awareness that they demonstrated regarding the condition. The emotional Stroop effect in response to dementia-related words in PwD indicates that preserved implicit awareness of the condition can be elicited even where there is reduced explicit awareness. Copyright © 2010 John Wiley & Sons, Ltd.

  13. High Performance Descriptive Semantic Analysis of Semantic Graph Databases

    Energy Technology Data Exchange (ETDEWEB)

    Joslyn, Cliff A.; Adolf, Robert D.; al-Saffar, Sinan; Feo, John T.; Haglin, David J.; Mackey, Greg E.; Mizell, David W.

    2011-06-02

    As semantic graph database technology grows to address components ranging from extant large triple stores to SPARQL endpoints over SQL-structured relational databases, it will become increasingly important to be able to understand their inherent semantic structure, whether codified in explicit ontologies or not. Our group is researching novel methods for what we call descriptive semantic analysis of RDF triplestores, to serve purposes of analysis, interpretation, visualization, and optimization. But data size and computational complexity makes it increasingly necessary to bring high performance computational resources to bear on this task. Our research group built a novel high performance hybrid system comprising computational capability for semantic graph database processing utilizing the large multi-threaded architecture of the Cray XMT platform, conventional servers, and large data stores. In this paper we describe that architecture and our methods, and present the results of our analyses of basic properties, connected components, namespace interaction, and typed paths such for the Billion Triple Challenge 2010 dataset.

  14. The Role of Simple Semantics in the Process of Artificial Grammar Learning.

    Science.gov (United States)

    Öttl, Birgit; Jäger, Gerhard; Kaup, Barbara

    2017-10-01

    This study investigated the effect of semantic information on artificial grammar learning (AGL). Recursive grammars of different complexity levels (regular language, mirror language, copy language) were investigated in a series of AGL experiments. In the with-semantics condition, participants acquired semantic information prior to the AGL experiment; in the without-semantics control condition, participants did not receive semantic information. It was hypothesized that semantics would generally facilitate grammar acquisition and that the learning benefit in the with-semantics conditions would increase with increasing grammar complexity. Experiment 1 showed learning effects for all grammars but no performance difference between conditions. Experiment 2 replicated the absence of a semantic benefit for all grammars even though semantic information was more prominent during grammar acquisition as compared to Experiment 1. Thus, we did not find evidence for the idea that semantics facilitates grammar acquisition, which seems to support the view of an independent syntactic processing component.

  15. Neurodegenerative Dementia

    International Nuclear Information System (INIS)

    Allard, Michelle

    2006-01-01

    Full text: With increasing life expectancy across the world, the number of elderly people at risk of developing dementia is growing rapidly. Thus, progressive neurodegenerative disorders such as dementia represent a growing public health concern. These diseases are characterized by a progressive loss in most of the cognitive functions. The promise, possibly in a near future, of disease-modifying therapies has made the characterization of the early stages of dementia a topic of major interest. The assessment of these early stages is a challenge for neuroimaging studies. In order to conceive prevention trials; it is of major outcome to fully understand the mechanisms of the cognitive system impairment and its evolution, with a particular reference to the symptomatic pre-dementia stage, when subjects just begin to depart from normality. In this article we review recent progress in neuroimaging, and their potentiality for increasing a diagnostic accuracy. (author)

  16. Differential diagnosis of neurodegenerative dementias with nuclear medicine methods

    International Nuclear Information System (INIS)

    Kluge, R.

    2015-01-01

    Full text: Neurodegenerative dementias (NDD) are characterized by insidious onset and gradual progression of cognitive dysfunction, initially relatively focal with respect to cognitive domains and brain regions involved. Nuclear medicine techniques help to clarify differential diagnoses of syndromes such as Alzheimer’s disease (AD), dementia with Lewy bodies (DlB), posterior cortical atrophy (PCA), logopenic primary progressive aphasia (PPA), agrammatic PPA, semantic dementia (SD), behavioral variant frontotemporal dementia (bvFTD) and progressive supranuclear palsy syndrome (PSPS). The process of pathologic changes in the brain may start decades before first clinical symptoms become evident. An early diagnosis already in the pre-clinical phase of the diseases will be of immense importance when expected effective therapeutic options have been introduced. NDDs are histopathologically characterized by accumulation of pathological proteins in the brain like beta amyloid or protein tau. While radiotracers for labeling of protein tau are in preclinical evaluation, different radiotracers labeling amyloid plaques ([11C]PIB, [18F]Florbetapir (Amyvid, Fa. EliLilly), [18F]Florbetaben (Neuraceq, Fa. Piramal), [18F]Flutemetamol (vVzamyl, Fa. Ge) have already been established in clinical use during the last years. In AD these tracers are intensively accumulated in the whole cortical brain. Even an early disease can be excluded in case of a negative amyloid PET. The method is, however, not highly specific since amyloid plaques may also be present in DlB (70 – 80%), FTD (30%) orlogopenicPPA (100%). Neuronal dysfunction goes along with decreased glucose consumption. Different diseases are characterized by different topographical zones of reduced [18F]FDG uptake. In AD the posterior cingular, temporopariatal and (later) frontal cortex are affected, in DlB the pattern is similar, including the occipital cortex, in FTD the frontal cortex is affected, in nonfluent PPA the

  17. How Chinese Semantics Capability Improves Interpretation in Visual Communication

    Science.gov (United States)

    Cheng, Chu-Yu; Ou, Yang-Kun; Kin, Ching-Lung

    2017-01-01

    A visual representation involves delivering messages through visually communicated images. The study assumed that semantic recognition can affect visual interpretation ability, and the result showed that students graduating from a general high school achieve satisfactory results in semantic recognition and image interpretation tasks than students…

  18. The Cost of Dementia in Denmark

    DEFF Research Database (Denmark)

    Kronborg Andersen, C; Søgaard, Jes; Hansen, E

    1999-01-01

    In a population-based study of dementia, the cost of care for 245 demented elderly and 490 controls matched by age and gender was estimated. Dementia of Alzheimer's type was diagnosed according to the NINCDS-ADRDA criteria, and vascular dementia and other types of dementia were diagnosed accordin...... with dementia and the matched controls and amounts on average to DKK 77,000 per person per year. However, priority setting cannot be based on the cost of dementia per se, but only on the cost of a specific dementia intervention compared to its health benefit.......In a population-based study of dementia, the cost of care for 245 demented elderly and 490 controls matched by age and gender was estimated. Dementia of Alzheimer's type was diagnosed according to the NINCDS-ADRDA criteria, and vascular dementia and other types of dementia were diagnosed according...... to the DSM-IIIR criteria. Severity of dementia was determined by the Clinical Dementia Rating scale. The annual cost of medical care, domestic care, home help, nursing home and special equipment for nondemented patients was DKK 22,000 per person while the cost for very mildly, mildly, moderately and severely...

  19. Methodological challenges in designing dementia prevention trials - The European Dementia Prevention Initiative (EDPI)

    NARCIS (Netherlands)

    Richard, Edo; Andrieu, Sandrine; Solomon, Alina; Mangialasche, Francesca; Ahtiluoto, Satu; Moll van Charante, Eric P.; Coley, Nicola; Fratiglioni, Laura; Neely, Anna Stigsdotter; Vellas, Bruno; van Gool, Willem A.; Kivipelto, Miia

    2012-01-01

    Recent epidemiological studies have indicated numerous associations between vascular and lifestyle related risk factors and incident dementia. However, evidence from randomised controlled trials (RCT) showing effectiveness of interventions aimed at these risk factors in preventing or postponing

  20. Early AIDS dementia complex

    International Nuclear Information System (INIS)

    Mountz, J.M.; Speed, N.M.; Adams, K.; Schwartz, J.A.; Gross, M.D.; Ostrow, D.G.

    1988-01-01

    A frequent complication of the acquired immunodeficiency syndrome (AIDS) is AIDS dementia complex (ADC). The authors evaluated seven patients with AIDS (aged 28-55 years, all male) for ADC by psychiatric evaluation, neuropsychological testing, CT scanning, and IMP-SPECT. Six of seven patients exhibited cognitive or behavioral abnormalities. Neuropsychological testing showed general deficits but no cases of explicit dementia. SPECT showed marked abnormalities in two cases: posterior temporal-parietal diminution of tracer uptake in one case (posterior/anterior=0.81) and marked right/left subcortical asymmetry (1.17) in the other. In three additional cases there was asymmetric tracer uptake in the subcortical and parietal regions. CT findings were normal in all seven cases. The authors conclude that functional imaging with the use of IMP-SPECT may be a useful method to follow ADC progression and response to therapy

  1. The role of semantic self-perceptions in temporal distance perceptions toward autobiographical events: the semantic congruence model.

    Science.gov (United States)

    Gebauer, Jochen E; Haddock, Geoffrey; Broemer, Philip; von Hecker, Ulrich

    2013-11-01

    Why do some autobiographical events feel as if they happened yesterday, whereas others feel like ancient history? Such temporal distance perceptions have surprisingly little to do with actual calendar time distance. Instead, psychologists have found that people typically perceive positive autobiographical events as overly recent, while perceiving negative events as overly distant. The origins of this temporal distance bias have been sought in self-enhancement strivings and mood congruence between autobiographical events and chronic mood. As such, past research exclusively focused on the evaluative features of autobiographical events, while neglecting semantic features. To close this gap, we introduce a semantic congruence model. Capitalizing on the Big Two self-perception dimensions, Study 1 showed that high semantic congruence between recalled autobiographical events and trait self-perceptions render the recalled events subjectively recent. Specifically, interpersonally warm (competent) individuals perceived autobiographical events reflecting warmth (competence) as relatively recent, but warm (competent) individuals did not perceive events reflecting competence (warmth) as relatively recent. Study 2 found that conscious perceptions of congruence mediate these effects. Studies 3 and 4 showed that neither mood congruence nor self-enhancement account for these results. Study 5 extended the results from the Big Two to the Big Five self-perception dimensions, while affirming the independence of the semantic congruence model from evaluative influences. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  2. Contribution of Pretesting to Several Measures of Semantic Desensitization Effectiveness

    Science.gov (United States)

    Israel, Allen C.; And Others

    1977-01-01

    Snake- or spider-phobic subjects (N=32) were randomly assigned to one of four groups. Subjects receiving semantic desensitization therapy showed less posttest anxiety on the semantic differential than control subjects regardless of testing condition. (Author)

  3. Alterações de linguagem em pacientes idosos portadores de demência avaliados com a Bateria MAC Language alterations in elderly patients with dementia assessed with the MAC Battery

    Directory of Open Access Journals (Sweden)

    Cristine Koehler

    2012-03-01

    , interpretation of metaphors and of narrative discourse, from the Montreal Communication Evaluation Battery - MAC Battery, as well as to verify the frequency of deficits. METHODS: Participants were 13 patients with mild to moderate dementia, treated at the Neurology sector of the Ambulatory of Movement Disorders and Dementia of the Hospital Santa Clara of the Irmandade Santa Casa de Misericórdia de Porto Alegre (ISCMPA. The neuropsychological assessment instrument was the MAC Battery, and the tasks were applied in the following order: free lexical retrieval, lexical retrieval based on orthographic criteria, lexical retrieval based on semantic criteria, interpretation of metaphors, and interpretation of narrative discourse. RESULTS: The group of patients with dementia showed impaired performance in all tasks from MAC Battery that were evaluated, with significant difference. Furthermore, participants presented higher frequency of deficits, in descending order, in partial retelling of narrative discourse tasks (essential and present information, followed by the tasks of lexical retrieval with orthography and semantic criteria, and full retelling of narrative discourse. At least two patients showed deficits in some of the five tasks performed from the MAC battery. CONCLUSION: Language evaluation using the MAC Battery allowed the verification of language processing deficits in elderly with dementia, characterizing that this instrument is also applicable to this clinical population.

  4. Brain Connectivity Alterations Are Associated with the Development of Dementia in Parkinson's Disease.

    Science.gov (United States)

    Bertrand, Josie-Anne; McIntosh, Anthony R; Postuma, Ronald B; Kovacevic, Natasha; Latreille, Véronique; Panisset, Michel; Chouinard, Sylvain; Gagnon, Jean-François

    2016-04-01

    Dementia affects a high proportion of Parkinson's disease (PD) patients and poses a burden on caregivers and healthcare services. Electroencephalography (EEG) is a common nonevasive and nonexpensive technique that can easily be used in clinical settings to identify brain functional abnormalities. Only few studies had identified EEG abnormalities that can predict PD patients at higher risk for dementia. Brain connectivity EEG measures, such as multiscale entropy (MSE) and phase-locking value (PLV) analyses, may be more informative and sensitive to brain alterations leading to dementia than previously used methods. This study followed 62 dementia-free PD patients for a mean of 3.4 years to identify cerebral alterations that are associated with dementia. Baseline resting state EEG of patients who developed dementia (N = 18) was compared to those of patients who remained dementia-free (N = 44) and of 37 healthy subjects. MSE and PLV analyses were performed. Partial least squares statistical analysis revealed group differences associated with the development of dementia. Patients who developed dementia showed higher signal complexity and lower PLVs in low frequencies (mainly in delta frequency) than patients who remained dementia-free and controls. Conversely, both patient groups showed lower signal variability and higher PLVs in high frequencies (mainly in gamma frequency) compared to controls, with the strongest effect in patients who developed dementia. These findings suggest that specific disruptions of brain communication can be measured before PD patients develop dementia, providing a new potential marker to identify patients at highest risk of developing dementia and who are the best candidates for neuroprotective trials.

  5. Depression and incident dementia. An 8-year population-based prospective study.

    Science.gov (United States)

    Luppa, Melanie; Luck, Tobias; Ritschel, Franziska; Angermeyer, Matthias C; Villringer, Arno; Riedel-Heller, Steffi G

    2013-01-01

    The aim of the study was to investigate the impact of depression (categorical diagnosis; major depression, MD) and depressive symptoms (dimensional diagnosis and symptom patterns) on incident dementia in the German general population. Within the Leipzig Longitudinal Study of the Aged (LEILA 75+), a representative sample of 1,265 individuals aged 75 years and older were interviewed every 1.5 years over 8 years (mean observation time 4.3 years; mean number of visits 4.2). Cox proportional hazards and binary logistic regressions were used to estimate the effect of baseline depression and depressive symptoms on incident dementia. The incidence of dementia was 48 per 1,000 person-years (95% confidence interval (CI) 45-51). Depressive symptoms (Hazard ratio HR 1.03, 95% CI 1.01-1.05), and in particular mood-related symptoms (HR 1.08, 95% CI 1.03-1.14), showed a significant impact on the incidence of dementia only in univariate analysis, but not after adjustment for cognitive and functional impairment. MD showed only a significant impact on incidence of dementia in Cox proportional hazards regression, but not in binary logistic regression models. The present study using different diagnostic measures of depression on future dementia found no clear significant associations of depression and incident dementia. Further in-depth investigation would help to understand the nature of depression in the context of incident dementia.

  6. The semantic basis of taste-shape associations

    Directory of Open Access Journals (Sweden)

    Carlos Velasco

    2016-02-01

    Full Text Available Previous research shows that people systematically match tastes with shapes. Here, we assess the extent to which matched taste and shape stimuli share a common semantic space and whether semantically congruent versus incongruent taste/shape associations can influence the speed with which people respond to both shapes and taste words. In Experiment 1, semantic differentiation was used to assess the semantic space of both taste words and shapes. The results suggest a common semantic space containing two principal components (seemingly, intensity and hedonics and two principal clusters, one including round shapes and the taste word “sweet,” and the other including angular shapes and the taste words “salty,” “sour,” and “bitter.” The former cluster appears more positively-valenced whilst less potent than the latter. In Experiment 2, two speeded classification tasks assessed whether congruent versus incongruent mappings of stimuli and responses (e.g., sweet with round versus sweet with angular would influence the speed of participants’ responding, to both shapes and taste words. The results revealed an overall effect of congruence with congruent trials yielding faster responses than their incongruent counterparts. These results are consistent with previous evidence suggesting a close relation (or crossmodal correspondence between tastes and shape curvature that may derive from common semantic coding, perhaps along the intensity and hedonic dimensions.

  7. An fMRI study of semantic processing in men with schizophrenia

    Science.gov (United States)

    Kubicki, M.; McCarley, R.W.; Nestor, P.G.; Huh, T.; Kikinis, R.; Shenton, M.E.; Wible, C.G.

    2009-01-01

    As a means toward understanding the neural bases of schizophrenic thought disturbance, we examined brain activation patterns in response to semantically and superficially encoded words in patients with schizophrenia. Nine male schizophrenic and 9 male control subjects were tested in a visual levels of processing (LOP) task first outside the magnet and then during the fMRI scanning procedures (using a different set of words). During the experiments visual words were presented under two conditions. Under the deep, semantic encoding condition, subjects made semantic judgments as to whether the words were abstract or concrete. Under the shallow, nonsemantic encoding condition, subjects made perceptual judgments of the font size (uppercase/lowercase) of the presented words. After performance of the behavioral task, a recognition test was used to assess the depth of processing effect, defined as better performance for semantically encoded words than for perceptually encoded words. For the scanned version only, the words for both conditions were repeated in order to assess repetition-priming effects. Reaction times were assessed in both testing scenarios. Both groups showed the expected depth of processing effect for recognition, and control subjects showed the expected increased activation of the left inferior prefrontal cortex (LIPC) under semantic encoding relative to perceptual encoding conditions as well as repetition priming for semantic conditions only. In contrast, schizophrenics showed similar patterns of fMRI activation regardless of condition. Most striking in relation to controls, patients showed decreased LIFC activation concurrent with increased left superior temporal gyrus activation for semantic encoding versus shallow encoding. Furthermore, schizophrenia subjects did not show the repetition priming effect, either behaviorally or as a decrease in LIPC activity. In patients with schizophrenia, LIFC underactivation and left superior temporal gyrus

  8. An fMRI study of semantic processing in men with schizophrenia.

    Science.gov (United States)

    Kubicki, M; McCarley, R W; Nestor, P G; Huh, T; Kikinis, R; Shenton, M E; Wible, C G

    2003-12-01

    As a means toward understanding the neural bases of schizophrenic thought disturbance, we examined brain activation patterns in response to semantically and superficially encoded words in patients with schizophrenia. Nine male schizophrenic and 9 male control subjects were tested in a visual levels of processing (LOP) task first outside the magnet and then during the fMRI scanning procedures (using a different set of words). During the experiments visual words were presented under two conditions. Under the deep, semantic encoding condition, subjects made semantic judgments as to whether the words were abstract or concrete. Under the shallow, nonsemantic encoding condition, subjects made perceptual judgments of the font size (uppercase/lowercase) of the presented words. After performance of the behavioral task, a recognition test was used to assess the depth of processing effect, defined as better performance for semantically encoded words than for perceptually encoded words. For the scanned version only, the words for both conditions were repeated in order to assess repetition-priming effects. Reaction times were assessed in both testing scenarios. Both groups showed the expected depth of processing effect for recognition, and control subjects showed the expected increased activation of the left inferior prefrontal cortex (LIPC) under semantic encoding relative to perceptual encoding conditions as well as repetition priming for semantic conditions only. In contrast, schizophrenics showed similar patterns of fMRI activation regardless of condition. Most striking in relation to controls, patients showed decreased LIFC activation concurrent with increased left superior temporal gyrus activation for semantic encoding versus shallow encoding. Furthermore, schizophrenia subjects did not show the repetition priming effect, either behaviorally or as a decrease in LIPC activity. In patients with schizophrenia, LIFC underactivation and left superior temporal gyrus

  9. The Image of Political Conflict: Evaluation Semantic Universals in Students’ Individual Mind

    OpenAIRE

    Virna, Zhanna

    2014-01-01

    Abstract. The paper is focused on the study of the political conflict image from the perspective of psychosemantics. The integral psychosemantic approach to the political conflict allowed establishing semantic universals viewed as students’ evaluation of the conflict’s image. Among the parameters were active, dangerous, open, rational, moral, close, aggressive, etc. The results of the students’ semantic space study through the semantic differential showed that the semantic constructs of “poli...

  10. A Defense of Semantic Minimalism

    Science.gov (United States)

    Kim, Su

    2012-01-01

    Semantic Minimalism is a position about the semantic content of declarative sentences, i.e., the content that is determined entirely by syntax. It is defined by the following two points: "Point 1": The semantic content is a complete/truth-conditional proposition. "Point 2": The semantic content is useful to a theory of…

  11. Depression, Dementia, and Social Supports.

    Science.gov (United States)

    Esser, Sally R.; Vitaliano, Peter P.

    1988-01-01

    Reviews recent literature on the relationships among dementia, depression, and social support, emphasizing the diagnostic differentiation of dementia and depression, and the role of these three entities in elderly with cognitive impairment. Discusses dementia-like symptoms arising in depression and the coexistence of dementia and depression.…

  12. Cognitive impairment of dementias

    OpenAIRE

    Medina, L. D.; Rodríguez-Agudelo, Yaneth

    2012-01-01

    Dementia is a clinical syndrome characterized by a loss of cognitive and emotional abilities of sufficient severity to infer with social or occupational functioning, or both. Although the causes of dementia and characteristics are not always fully understood, it is understood that it is not a natural part of aging. Definitive diagnosis of dementia is made only through the autopsy and although the diagnosis of probable or possible dementia is complex is achieved by the intervention of several ...

  13. Personal semantic memory: insights from neuropsychological research on amnesia.

    Science.gov (United States)

    Grilli, Matthew D; Verfaellie, Mieke

    2014-08-01

    This paper provides insight into the cognitive and neural mechanisms of personal semantic memory, knowledge that is specific and unique to individuals, by reviewing neuropsychological research on stable amnesia secondary to medial temporal lobe damage. The results reveal that personal semantic memory does not depend on a unitary set of cognitive and neural mechanisms. Findings show that autobiographical fact knowledge reflects an experience-near type of personal semantic memory that relies on the medial temporal lobe for retrieval, albeit less so than personal episodic memory. Additional evidence demonstrates that new autobiographical fact learning likely relies on the medial temporal lobe, but the extent to which remains unclear. Other findings show that retrieval of personal traits/roles and new learning of personal traits/roles and thoughts/beliefs are independent of the medial temporal lobe and thus may represent highly conceptual types of personal semantic memory that are stored in the neocortex. Published by Elsevier Ltd.

  14. Semantic Information Extraction of Lanes Based on Onboard Camera Videos

    Science.gov (United States)

    Tang, L.; Deng, T.; Ren, C.

    2018-04-01

    In the field of autonomous driving, semantic information of lanes is very important. This paper proposes a method of automatic detection of lanes and extraction of semantic information from onboard camera videos. The proposed method firstly detects the edges of lanes by the grayscale gradient direction, and improves the Probabilistic Hough transform to fit them; then, it uses the vanishing point principle to calculate the lane geometrical position, and uses lane characteristics to extract lane semantic information by the classification of decision trees. In the experiment, 216 road video images captured by a camera mounted onboard a moving vehicle were used to detect lanes and extract lane semantic information. The results show that the proposed method can accurately identify lane semantics from video images.

  15. Arabic web pages clustering and annotation using semantic class features

    Directory of Open Access Journals (Sweden)

    Hanan M. Alghamdi

    2014-12-01

    Full Text Available To effectively manage the great amount of data on Arabic web pages and to enable the classification of relevant information are very important research problems. Studies on sentiment text mining have been very limited in the Arabic language because they need to involve deep semantic processing. Therefore, in this paper, we aim to retrieve machine-understandable data with the help of a Web content mining technique to detect covert knowledge within these data. We propose an approach to achieve clustering with semantic similarities. This approach comprises integrating k-means document clustering with semantic feature extraction and document vectorization to group Arabic web pages according to semantic similarities and then show the semantic annotation. The document vectorization helps to transform text documents into a semantic class probability distribution or semantic class density. To reach semantic similarities, the approach extracts the semantic class features and integrates them into the similarity weighting schema. The quality of the clustering result has evaluated the use of the purity and the mean intra-cluster distance (MICD evaluation measures. We have evaluated the proposed approach on a set of common Arabic news web pages. We have acquired favorable clustering results that are effective in minimizing the MICD, expanding the purity and lowering the runtime.

  16. Frontotemporal dementia with severe thalamic involvement : a clinical and neuropathological study

    Directory of Open Access Journals (Sweden)

    Radanovic Márcia

    2003-01-01

    Full Text Available Frontotemporal dementia (FTD is the third-leading cause of cortical dementia after Alzheimer's disease and Lewy body dementia, and is characterized by a dementia where behavioral disturbances are prominent and appear early in the course of the disease. We report the case of a 58 year-old man affected by dementia with behavioral disturbances, in addition to rigid-hypokinetic and a lower motor neuron syndrome that were present at later stages of the illness. Neuroimaging studies showed frontotemporal atrophy. Neuropathological studies revealed intense thalamic neuronal loss and astrocytic gliosis, as well as moderate frontotemporal neuronal loss, astrocytosis and spongiform degeneration. Thalamic degeneration has previously been described among the wide group of neuropathological features of FTD. The aim of the present study is to show the clinical and neuropathological aspects of thalamic degeneration in FTD, along with its role in behavioral disturbances, a common finding in this condition.

  17. Individual Music Therapy with Persons with Frontotemporal Dementia

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner; Aldridge, David

    2005-01-01

    It is possible to slow down the progression of Alzheimer’s disease with pharmacological treatment. When this treatment is given to people with types of dementia that affect the frontal and temporal lobes (Frontotemporal Dementia) the results are discouraging. It is observed that the patients show...... is an integration of a relational music therapy approach and a more physiologically based arousal model, and is here illustrated in a case study research that integrated both qualitative and quantitative data in a flexible research design.......It is possible to slow down the progression of Alzheimer’s disease with pharmacological treatment. When this treatment is given to people with types of dementia that affect the frontal and temporal lobes (Frontotemporal Dementia) the results are discouraging. It is observed that the patients show...... pronounced restlessness and mania. In this article we describe a non-pharmacological psychosocial approach, music therapy, and how it is possible to work with this method when constitutional, regulative, dialogical, and integrative aspects are included. The focus is on therapeutic singing where well known...

  18. Early Dementia Screening

    Directory of Open Access Journals (Sweden)

    Peter K. Panegyres

    2016-01-01

    Full Text Available As the population of the world increases, there will be larger numbers of people with dementia and an emerging need for prompt diagnosis and treatment. Early dementia screening is the process by which a patient who might be in the prodromal phases of a dementing illness is determined as having, or not having, the hallmarks of a neurodegenerative condition. The concepts of mild cognitive impairment, or mild neurocognitive disorder, are useful in analyzing the patient in the prodromal phase of a dementing disease; however, the transformation to dementia may be as low as 10% per annum. The search for early dementia requires a comprehensive clinical evaluation, cognitive assessment, determination of functional status, corroborative history and imaging (including MRI, FDG-PET and maybe amyloid PET, cerebrospinal fluid (CSF examination assaying Aβ1–42, T-τ and P-τ might also be helpful. Primary care physicians are fundamental in the screening process and are vital in initiating specialist investigation and treatment. Early dementia screening is especially important in an age where there is a search for disease modifying therapies, where there is mounting evidence that treatment, if given early, might influence the natural history—hence the need for cost-effective screening measures for early dementia.

  19. Open semantic analysis: The case of word level semantics in Danish

    DEFF Research Database (Denmark)

    Nielsen, Finn Årup; Hansen, Lars Kai

    2017-01-01

    The present research is motivated by the need for accessible and efficient tools for automated semantic analysis in Danish. We are interested in tools that are completely open, so they can be used by a critical public, in public administration, non-governmental organizations and businesses. We...... describe data-driven models for Danish semantic relatedness, word intrusion and sentiment prediction. Open Danish corpora were assembled and unsupervised learning implemented for explicit semantic analysis and with Gensim’s Word2vec model. We evaluate the performance of the two models on three different...... annotated word datasets. We test the semantic representations’ alignment with single word sentiment using supervised learning. We find that logistic regression and large random forests perform well with Word2vec features....

  20. Cobalamin deficiency, hyperhomocysteinemia, and dementia

    Directory of Open Access Journals (Sweden)

    Steven F Werder

    2010-04-01

    : 200 picograms per milliliter or less is low, and 201 to 350 picograms per milliliter is borderline low. Other tests may be indicated, including plasma homocysteine, serum methylmalonic acid, antiparietal cell and anti-intrinsic factor antibodies, and serum gastrin level. In B12 deficiency dementia with versus without pernicious anemia, there appear to be different manifestations, need for further workup, and responses to treatment. Dementia of the Alzheimer’s type is a compatible diagnosis when B12 deficiency is found, unless it is caused by pernicious anemia. Patients with pernicious anemia generally respond favorably to supplemental B12 treatment, especially if pernicious anemia is diagnosed early in the course of the disease. Some patients without pernicious anemia, but with B12 deficiency and either mild cognitive impairment or mild to moderate dementia, might show some degree of cognitive improvement with supplemental B12 treatment. Evidence that supplemental B12 treatment is beneficial for patients without pernicious anemia, but with B12 deficiency and moderately-severe to severe dementia is scarce. Oral cyanocobalamin is generally favored over intramuscular cyanocobalamin.Keywords: Alzheimer, dementia, cognitive impairment, cognitive dysfunction, cobalamin, cyanocobalamin, B12, homocysteine, hyperhomocysteinemia, homocystinuria

  1. Applied Semantic Web Technologies

    CERN Document Server

    Sugumaran, Vijayan

    2011-01-01

    The rapid advancement of semantic web technologies, along with the fact that they are at various levels of maturity, has left many practitioners confused about the current state of these technologies. Focusing on the most mature technologies, Applied Semantic Web Technologies integrates theory with case studies to illustrate the history, current state, and future direction of the semantic web. It maintains an emphasis on real-world applications and examines the technical and practical issues related to the use of semantic technologies in intelligent information management. The book starts with

  2. Etiologies and risk factors for dementia

    Directory of Open Access Journals (Sweden)

    Sandeep Grover

    2016-01-01

    Full Text Available Dementia is understood as a clinical syndrome characterized by impairment in memory impairment along with cognitive deficits in other domains. Over the years, understanding about the causes of dementias has improved. Broadly, dementias can be classified as irreversible degenerative dementias and reversible dementias. Alzheimer′s disease is the prototype of degenerative dementias and is characterized by the accumulation of beta-amyloid protein (called as amyloid plaques outside the neurons and accumulation of tau protein (called tau tangles inside the neurons. Vascular dementias are characterized by cerebrovascular insults which lead to pathological brain changes that impair cognition. The pathological hallmark of Lewy body dementia is the presence of α-synuclein neuronal inclusions, also known as Lewy bodies, accompanied by neuronal loss. Frontotemporal dementias are characterized by abnormal deposits of the microtubule-associated protein tau, the trans-activation response TAR DNA-binding protein with molecular weight 43 kDa (TDP-43, and the fused in sarcoma protein. Reversible dementias are characterized by the primary illness and may not present with characteristic brain deposits as seen with many degenerative dementias.

  3. Prevalence of major depressive disorder and dementia in psychogeriatric outpatients.

    Science.gov (United States)

    Chinello, A; Grumelli, B; Perrone, C; Annoni, G

    2007-01-01

    The relationship between depression and dementia in the elderly has been widely investigated, but the real interplay between these variables is still not clear. This observational study highlights the influence of some basic variables, such as sex and age, in the development of dementia and major depression. It shows (i) the importance of sex in the age of onset of depression and dementia, (ii) the presence of two types of depressive syndrome, the first linked to the development of dementia, the second as reactive depression; (iii) the need for more attention to depressive symptoms in young-elderly men.

  4. A qualitative study of older and middle-aged adults' perception and attitudes towards dementia and dementia risk reduction.

    Science.gov (United States)

    Kim, Sarang; Sargent-Cox, Kerry A; Anstey, Kaarin J

    2015-07-01

    To investigate perceptions of dementia and dementia risk reduction held by people without dementia. Dementia does not only affect individuals with dementia, but also has an impact on family and friends, society and healthcare professionals. Recent research has identified modifiable risk and protective factors for dementia. However, it is unclear what knowledge people without dementia have about these risk factors and their attitudes towards addressing these risk factors to achieve dementia risk reduction are not known. Qualitative descriptive study using focus group methodology. A focus group study was conducted in February 2011 with 34 older adults aged between 52-90 years. The long-table approach was used to identify themes and categorize data on dementia knowledge, risk and attitudes. Participants correctly identified dementia risk factors as a group. Participants' responses about their perceived likelihood of developing dementia could be classified into three distinctive themes; fear, rational and cynical perceptions. Both fear of developing dementia and the need to improve dementia knowledge were considered major motivators towards adopting healthier lifestyle and health behaviours. Lack of knowledge on risk factors for dementia was identified as a major barrier for behavioural and lifestyle change. These findings can be used to develop effective and personalized interventions that increase motivators and reduce barriers by tailoring interventions to individual's dementia risk reduction literacy and motivations to change behaviours. Greater public-health promotion and education about risk and protective factors for dementia are also necessary to increase dementia health literacy and to reduce overall dementia prevalence. © 2015 John Wiley & Sons Ltd.

  5. Cognitive training for dementia

    Directory of Open Access Journals (Sweden)

    Konta, Brigitte

    2005-12-01

    Full Text Available The aim of the HTA report is to evaluate the effectiveness of cognitive training methods to treat cognitive disorders of dementia and other diseases with cognitive deficits. For this purpose, a systematic literature search was carried out first based on the DIMDI superbase retrieval. The identified publications were judged and selected by two independent, methodically competent experts. 33 publications were included in the report. Based on the studies for a normal cognitive development in old age a theory that healthy older people have a considerable capacity reserve for an improved performance in abstract abilities of thinking can be assumed. The first symptoms for older people at risk for dementia are a reduced cognitive capacity reserve. Cognitive training methods therefore focus abilities of abstract memory. Apart from types of dementia another two groups of diseases with cognitive deficits were included in the HTA report: cerebral lesions and schizophrenic psychoses. Studies with mild as well as forms of dementia heavy forms including the Alzheimer disease were included. The described training methods were very heterogeneous with regard to their contents, the temporal sequence and the outcome parameter. The studies were methodically partly contestable. Approximately a third of the studies of all publications could show improvements in the cognitive achievements by the training. Three studies concerning cognitive training methods in case of cerebral lesions were included. All three studies demonstrated a significant improvement in the training group in some outcome parameters. Special cognitive training methods were used for the treatment of cognitive deficits at schizophrenic psychoses. The neurocognitive training (NET, the "Cognitive Remediation Therapy" as well as the strategic training with coaching proved to be effective. The studies, however, were hardly comparable and very heterogeneous in detail. Summarising the cognitive training

  6. Intelligence related upper alpha desynchronization in a semantic memory task.

    Science.gov (United States)

    Doppelmayr, M; Klimesch, W; Hödlmoser, K; Sauseng, P; Gruber, W

    2005-07-30

    Recent evidence shows that event-related (upper) alpha desynchronization (ERD) is related to cognitive performance. Several studies observed a positive, some a negative relationship. The latter finding, interpreted in terms of the neural efficiency hypothesis, suggests that good performance is associated with a more 'efficient', smaller extent of cortical activation. Other studies found that ERD increases with semantic processing demands and that this increase is larger for good performers. Studies supporting the neural efficiency hypothesis used tasks that do not specifically require semantic processing. Thus, we assume that the lack of semantic processing demands may at least in part be responsible for the reduced ERD. In the present study we measured ERD during a difficult verbal-semantic task. The findings demonstrate that during semantic processing, more intelligent (as compared to less intelligent) subjects exhibited a significantly larger upper alpha ERD over the left hemisphere. We conclude that more intelligent subjects exhibit a more extensive activation in a semantic processing system and suggest that divergent findings regarding the neural efficiency hypotheses are due to task specific differences in semantic processing demands.

  7. Depression associated with dementia.

    Science.gov (United States)

    Gutzmann, H; Qazi, A

    2015-06-01

    Depression and cognitive disorders, including dementia and mild cognitive impairment, are common disorders in old age. Depression is frequent in dementia, causing distress, reducing the quality of life, exacerbating cognitive and functional impairment and increasing caregiver stress. Even mild levels of depression can significantly add to the functional impairment of dementia patients and the severity of psychopathological and neurological impairments increases with increasing severity of depression. Depressive symptoms may be both a risk factor for, as well as a prodrome of dementia. Major depressive syndrome of Alzheimer's disease may be among the most common mood disorders of older adults. Treating depression is therefore a key clinical priority to improve the quality of life both of people with dementia as well as their carergivers. Nonpharmacological approaches and watchful waiting should be attempted first in patients who present with mild to moderate depression and dementia. In cases of severe depression or depression not able to be managed through nonpharmacological means, antidepressant therapy should be considered.

  8. Brain perfusion SPECT with Brodmann areas analysis in differentiating frontotemporal dementia subtypes.

    Science.gov (United States)

    Valotassiou, Varvara; Papatriantafyllou, John; Sifakis, Nikolaos; Tzavara, Chara; Tsougos, Ioannis; Psimadas, Dimitrios; Kapsalaki, Eftychia; Fezoulidis, Ioannis; Hadjigeorgiou, George; Georgoulias, Panagiotis

    2014-01-01

    Despite the known validity of clinical diagnostic criteria, significant overlap of clinical symptoms between Frontotemporal dementia (FTD) subtypes exists in several cases, resulting in great uncertainty of the diagnostic boundaries. We evaluated the perfusion between FTD subtypes using brain perfusion (99m)Tc-HMPAO SPECT with Brodmann areas (BA) mapping. NeuroGam software was applied on single photon emission computed tomographic (SPECT) studies for the semi-quantitative evaluation of perfusion in BA and the comparison with the software's normal database. We studied 91 consecutive FTD patients: 21 with behavioural variants (bvFTD), 39 with language variants (lvFTD) [12 with progressive non-fluent aphasia (PNFA), 27 with semantic dementia (SD)], and 31 patients with progressive supranuclear palsy (PSP)/corticobasal degeneration (CBD). Stepwise logistic regression analyses showed that the BA 28L and 32R could independently differentiate bvFTD from lvFTD, while the BA 8R and 25R could discriminate bvFTD from SD and PNFA, respectively. Additionally, BA 7R and 32R were found to discriminate bvFTD from CBD/PSP. The only BA that could differentiate SD from PNFA was 6L. BA 6R and 20L were found to independently differentiate CBD/PSP from lvFTD. Moreover, BA 20L and 22R could discriminate CBD/PSP from PNFA, while BA 6R, 20L and 45R were found to independently discriminate CBD/PSP from SD. Brain perfusion SPECT with BA mapping can be a useful additional tool in differentiating FTD variants by improving the definition of brain areas that are specifically implicated, resulting in a more accurate differential diagnosis in atypical or uncertain forms of FTD.

  9. Brain perfusion SPECT in dementia syndromes

    International Nuclear Information System (INIS)

    Libus, P.; Stupalova, J.; Kuzelka, I.; Konrad, J.

    2002-01-01

    Aim: Brain perfusion SPECT is used in differential diagnostics of dementia syndromes. First of all the aim is to distinguish vascular dementia from degenerative dementia and to differentiate dementia from delirium, psychiatric syndromes, depression and secondary dementia, which is important in relation to therapy. The purpose of our study was to detect significance of BP SPECT and include it into the diagnostic process in dementia syndromes. Materials and methods: 51 women and 63 men aged 55 - 88 were evaluated in the study. The patients correspond to the general criteria of dementia diagnosis. They were sent to the examination by neurological, internal and psychiatric departments and out-patient departments. All patients were examined by 99mTc ECD SPECT using a double head camera PRISM 200 VP with LEHR collimator. The scintigraphic data were evaluated by the visual and semiquantitative analysis. Results: It was established that most patients in our group had vascular dementia, while Alzheimer's disease was second. In other groups we found out dementia at strategic infarct location, e.g. in gyrus angularis in the dominant hemisphere, frontal temporal lobe dementia and alcoholic dementia. Twenty-four patients had a normal diagnosis. Fifteen of them had a somatic reason of the delirious state and were re-classified into pseudodementia. Nine patients were not diagnostically included and the examination will repeated in four months time. Conclusion: We have found out a good applicability of brain perfusion SPECT in dementia syndromes diagnosis in our work. The best diagnosticable and most specific were the findings in multi-infarct dementia, Alzheimer's disease and frontal temporal lobe dementia. When vascular dementia is concerned we can even distinguish dementia at strategic infarction location, e.g. in thalamus, basal frontal telencefalon, in gyrus angularis of the dominant hemisphere, etc

  10. Impaired imitation of gestures in mild dementia: comparison of dementia with Lewy bodies, Alzheimer's disease and vascular dementia.

    Science.gov (United States)

    Nagahama, Yasuhiro; Okina, Tomoko; Suzuki, Norio

    2015-11-01

    To examine whether imitation of gestures provided useful information to diagnose early dementia in elderly patients. Imitation of finger and hand gestures was evaluated in patients with mild dementia; 74 patients had dementia with Lewy bodies (DLB), 100 with Alzheimer's disease (AD) and 52 with subcortical vascular dementia (SVaD). Significantly, more patients with DLB (32.4%) compared with patients with AD (5%) or SVaD (11.5%) had an impaired ability to imitate finger gestures bilaterally. Also, significantly, more patients with DLB (36.5%) compared with patients with AD (5%) or SVaD (15.4%) had lower mean scores of both hands. In contrast, impairment of the imitation of bimanual gestures was comparable among the three patient groups (DLB 50%, AD 42%, SVaD 42.3%). Our study revealed that imitation of bimanual gestures was impaired non-specifically in about half of the patients with mild dementia, whereas imitation of finger gestures was significantly more impaired in patients with early DLB than in those with AD or SVaD. Although the sensitivity was not high, the imitation tasks may provide additional information for diagnosis of mild dementia, especially for DLB. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. Difference in MRI findings and risk factors between multiple infarction without dementia and multi-infarct dementia

    International Nuclear Information System (INIS)

    Yanagisawa, Masashi; Kaieda, Makoto; Nagatsumi, Atsushi; Terashi, Akiro

    1995-01-01

    MRI findings and risk factors for vascular dementia were evaluated with multi-variate analysis in 96 multi-infarct patients without dementia and 40 multi-infarct patients with dementia (MID). Only subjects with small infarcts in the territory of the perforator artery or deep white matter were studied. The diagnosis of MID was diagnosed according to DMS-III criteria and Hachinski's ischemia score. Location and area of patchy high-intensity areas including small infarcts, the degree of periventricular high intensity (PVH), and the degree of brain atrophy were examined with MR images. Independent variables were: history of hypertension, diabetes mellitus, other complications; systolic and diastolic blood pressure, atherosclerotic index, hematocrit, history of smoking, level of education, and activities of daily life (ADL). Hayashi's quantification method II was used to analyze the data. The most significant correlation was found between history of hypertension and dementia (partial correlation coefficient: 0.39). Significant correlations were also found between ADL and dementia (0.32), between thalamic infarction and dementia (0.31), and between PVH and dementia (0.27). Age, brain atrophy index, and history of diabetes mellitus contributed little to dementia. The contribution to dementia did not differ significantly between right and left patchy high-intensity areas on MR images. Location of infarcts, except for bilateral thalamic infarcts and large PVH, contributed little to dementia. Thus it would be difficult to base a prediction of the prevalence of vascular dementia on MRI findings. However, both hypertention and ADL contribute to vascular dementia and both are treatable, which may be significant for the prevention of dementia. (author)

  12. Contextual Semantic Parsing using Crowdsourced Spatial Descriptions

    OpenAIRE

    Dukes, Kais

    2014-01-01

    We describe a contextual parser for the Robot Commands Treebank, a new crowdsourced resource. In contrast to previous semantic parsers that select the most-probable parse, we consider the different problem of parsing using additional situational context to disambiguate between different readings of a sentence. We show that multiple semantic analyses can be searched using dynamic programming via interaction with a spatial planner, to guide the parsing process. We are able to parse sentences in...

  13. Cognitive profiling of Parkinson disease patients with mild cognitive impairment and dementia.

    Science.gov (United States)

    Biundo, Roberta; Weis, Luca; Facchini, Silvia; Formento-Dojot, Patrizia; Vallelunga, Annamaria; Pilleri, Manuela; Antonini, Angelo

    2014-04-01

    Prevalence of mild cognitive impairment (MCI) and dementia in Parkinson disease (PD) is variable because different classification criteria are applied and there is lack of consensus about neuropsychological tests and cut-off used for cognitive profiling. Given the important therapeutic consequences for patient management, we aimed at identifying suitable diagnostic cognitive tests and respective screening cut-off values for MCI and dementia in PD (PDD). We evaluated 105 PD patients using an extensive neuropsychological battery categorized as PD without cognitive impairment (PD-CNT) (35%), PD-MCI (47%) and PDD (18%) based on established criteria and calculated Receiver Operating Characteristic (ROC) curves. We found different sensitivity and specificity among neuropsychological tests in detecting PD-MCI and PDD. In particular performance in attention/set shifting, verbal memory and language abilities, discriminated both PD-MCI and PDD from PD-CNT. Abilities involved mainly in semantic retrieval mechanisms discriminated PD-CNT from PD-MCI but also PD-MCI from PDD. Finally deficits in executive and visual-spatial abilities were only affected in PDD. Our data point to an independent and different load of each test in defining different PD cognitive statuses. These findings can help selection of appropriate cognitive batteries in longitudinal studies and definition of stage-specific therapeutic targets. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Adventures in semantic publishing: exemplar semantic enhancements of a research article.

    Directory of Open Access Journals (Sweden)

    David Shotton

    2009-04-01

    Full Text Available Scientific innovation depends on finding, integrating, and re-using the products of previous research. Here we explore how recent developments in Web technology, particularly those related to the publication of data and metadata, might assist that process by providing semantic enhancements to journal articles within the mainstream process of scholarly journal publishing. We exemplify this by describing semantic enhancements we have made to a recent biomedical research article taken from PLoS Neglected Tropical Diseases, providing enrichment to its content and increased access to datasets within it. These semantic enhancements include provision of live DOIs and hyperlinks; semantic markup of textual terms, with links to relevant third-party information resources; interactive figures; a re-orderable reference list; a document summary containing a study summary, a tag cloud, and a citation analysis; and two novel types of semantic enrichment: the first, a Supporting Claims Tooltip to permit "Citations in Context", and the second, Tag Trees that bring together semantically related terms. In addition, we have published downloadable spreadsheets containing data from within tables and figures, have enriched these with provenance information, and have demonstrated various types of data fusion (mashups with results from other research articles and with Google Maps. We have also published machine-readable RDF metadata both about the article and about the references it cites, for which we developed a Citation Typing Ontology, CiTO (http://purl.org/net/cito/. The enhanced article, which is available at http://dx.doi.org/10.1371/journal.pntd.0000228.x001, presents a compelling existence proof of the possibilities of semantic publication. We hope the showcase of examples and ideas it contains, described in this paper, will excite the imaginations of researchers and publishers, stimulating them to explore the possibilities of semantic publishing for their own

  15. Pascal Semantics by a Combination of Denotational Semantics and High-level Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Schmidt, Erik Meineche

    1986-01-01

    This paper describes the formal semantics of a subset of PASCAL, by means of a semantic model based on a combination of denotational semantics and high-level Petri nets. It is our intention that the paper can be used as part of the written material for an introductory course in computer science....

  16. Dementia and serious coexisting medical conditions: a double whammy.

    Science.gov (United States)

    Maslow, Katie

    2004-09-01

    Research-based information about the prevalence of other serious medical conditions in people with dementia has become available only recently, and the true prevalence is not known, primarily because many people with dementia do not have a diagnosis. The existing information is sufficient, however, to show that these other conditions are common in people with dementia. It is also clear that coexisting medical conditions increase the use and cost of health care services for people with dementia, and conversely, dementia increases the use and cost of health care services for people with other serious medical conditions. Nurses and other healthcare professionals should expect to see these relationships in their elderly patients. They should know how to recognize possible dementia and assess, or obtain an assessment of, the patient's cognitive status. They should expect the worsening of cognitive and related symptoms in acutely ill people with dementia and try to eliminate factors that cause this worsening, to the extent possible, while assuring the family that the symptoms are likely to improve once the acute phase of illness or treatment is over. Families, nurses, and other health care professionals are challenged by the complex issues involved in caring for a person with both dementia and other serious medical conditions. Greater attention to these issues by informed and thoughtful clinicians will improve outcomes for the people and their family and professional caregivers.

  17. Auditing the Assignments of Top-Level Semantic Types in the UMLS Semantic Network to UMLS Concepts.

    Science.gov (United States)

    He, Zhe; Perl, Yehoshua; Elhanan, Gai; Chen, Yan; Geller, James; Bian, Jiang

    2017-11-01

    The Unified Medical Language System (UMLS) is an important terminological system. By the policy of its curators, each concept of the UMLS should be assigned the most specific Semantic Types (STs) in the UMLS Semantic Network (SN). Hence, the Semantic Types of most UMLS concepts are assigned at or near the bottom (leaves) of the UMLS Semantic Network. While most ST assignments are correct, some errors do occur. Therefore, Quality Assurance efforts of UMLS curators for ST assignments should concentrate on automatically detected sets of UMLS concepts with higher error rates than random sets. In this paper, we investigate the assignments of top-level semantic types in the UMLS semantic network to concepts, identify potential erroneous assignments, define four categories of errors, and thus provide assistance to curators of the UMLS to avoid these assignments errors. Human experts analyzed samples of concepts assigned 10 of the top-level semantic types and categorized the erroneous ST assignments into these four logical categories. Two thirds of the concepts assigned these 10 top-level semantic types are erroneous. Our results demonstrate that reviewing top-level semantic type assignments to concepts provides an effective way for UMLS quality assurance, comparing to reviewing a random selection of semantic type assignments.

  18. Dementia.

    Science.gov (United States)

    Nardone, Raffaele; Golaszewski, Stefan; Trinka, Eugen

    2013-01-01

    Transcranial magnetic stimulation (TMS) has been used extensively to characterize motor system pathophysiology in Alzheimer's disease (AD) and other forms of dementia, as well to monitor the effects of certain pharmacological agents. Among the studies focusing on motor cortical excitability measures, the most consistent finding is a significant reduction of short-latency afferent inhibition (SAI) in AD and other forms of dementia in which the cholinergic system is affected, such as dementia with Lewy bodies. SAI evaluation may thus provide a reliable biomarker of cortical cholinergic dysfunction in dementias. Moreover, most TMS studies have demonstrated cortical hyperexcitability and asymptomatic motor cortex functional reorganization in the early stages of the disease. Integrated approaches utilizing TMS together with high-density EEG have indicated impaired cortical plasticity and functional connectivity across different neural networks in AD. Paired associative stimulation-induced plasticity has also been found to be abnormal in patients with AD. The development of novel noninvasive methods of brain stimulation, in particular repetitive TMS (rTMS) and transcranial direct current stimulation (tDCS), has increased the interest in neuromodulatory techniques as potential therapeutic tools for cognitive rehabilitation in AD. Preliminary studies have revealed that rTMS and tDCS can induce beneficial effects on specific cognitive functions in AD. Future studies are warranted to replicate and extend the initial findings. © 2013 Elsevier B.V. All rights reserved.

  19. Awareness of dementia by family carers of nursing home residents dying with dementia: a post-death study.

    Science.gov (United States)

    Penders, Yolanda W H; Albers, Gwenda; Deliens, Luc; Vander Stichele, Robert; Van den Block, Lieve

    2015-01-01

    High-quality palliative care for people with dementia should be patient-centered, family-focused, and include well-informed and shared decision-making, as affirmed in a recent white paper on dementia from the European Association for Palliative Care. To describe how often family carers of nursing home residents who died with dementia are aware that their relative has dementia, and study resident, family carer, and care characteristics associated with awareness. Post-death study using random cluster sampling. Structured questionnaires were completed by family carers, nursing staff, and general practitioners of deceased nursing home residents with dementia in Flanders, Belgium (2010). Of 190 residents who died with dementia, 53.2% of family carers responded. In 28% of cases, family carers indicated they were unaware their relative had dementia. Awareness by family carers was related to more advanced stages of dementia 1 month before death (odds ratio = 5.4), with 48% of family carers being unaware when dementia was mild and 20% unaware when dementia was advanced. The longer the onset of dementia after admission to a nursing home, the less likely family carers were aware (odds ratio = 0.94). Family carers are often unaware that their relative has dementia, that is, in one-fourth of cases of dementia and one-fifth of advanced dementia, posing considerable challenges for optimal care provision and end-of-life decision-making. Considering that family carers of residents who develop dementia later after admission to a nursing home are less likely to be aware, there is room for improving communication strategies toward family carers of nursing home residents. © The Author(s) 2014.

  20. Two-Level Semantics and Code Generation

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis

    1988-01-01

    A two-level denotational metalanguage that is suitable for defining the semantics of Pascal-like languages is presented. The two levels allow for an explicit distinction between computations taking place at compile-time and computations taking place at run-time. While this distinction is perhaps...... not absolutely necessary for describing the input-output semantics of programming languages, it is necessary when issues such as data flow analysis and code generation are considered. For an example stack-machine, the authors show how to generate code for the run-time computations and still perform the compile...

  1. Distinct perfusion patterns in Alzheimer's disease, frontotemporal dementia and dementia with Lewy bodies

    Energy Technology Data Exchange (ETDEWEB)

    Binnewijzend, Maja A.A.; Wattjes, Mike P.; Berckel, Bart N.M. van; Barkhof, Frederik [VU University Medical Center and Neuroscience Campus Amsterdam, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); Kuijer, Joost P.A. [VU University Medical Center and Neuroscience Campus Amsterdam, Department of Physics and Medical Technology, Amsterdam (Netherlands); Flier, Wiesje M. van der [VU University Medical Center and Neuroscience Campus Amsterdam, Alzheimercenter and Department of Neurology, Amsterdam (Netherlands); VU University Medical Center and Neuroscience Campus Amsterdam, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands); Benedictus, Marije R.; Moeller, Christiane M.; Pijnenburg, Yolande A.L.; Lemstra, Afina W.; Prins, Niels D.; Scheltens, Philip [VU University Medical Center and Neuroscience Campus Amsterdam, Alzheimercenter and Department of Neurology, Amsterdam (Netherlands)

    2014-09-15

    To compare pseudo-continuous arterial spin-labelled (PCASL) magnetic resonance imaging (MRI) measured quantitative cerebral blood flow (CBF) of patients with frontotemporal dementia (FTD), dementia with Lewy Bodies (DLB), Alzheimer's disease (AD) and controls, in a region of interest (ROI) and voxel-wise fashion. We analysed whole-brain 3D fast-spin-echo PCASL images of 20 FTD patients, 14 DLB patients, 48 AD patients and 50 controls from the Amsterdam Dementia Cohort. Regional CBF patterns were compared using analyses of variance for repeated measures. Permutation tests were used for voxel-wise comparisons. Analyses were performed using uncorrected and partial volume corrected (PVC) maps. All analyses were corrected for age and sex. There was an interaction between diagnosis and region (p < 0.001), implying differences in regional CBF changes between diagnostic groups. In AD patients, CBF was decreased in all supratentorial regions, most prominently so in the posterior regions. DLB patients showed lowest CBF values throughout the brain, but temporal CBF was preserved. Supratentorial PVC cortical CBF values were lowest in the frontal lobes in FTD patients, and in the temporal lobes in AD patients. Patients with AD, FTD and DLB display distinct patterns of quantitative regional CBF changes. 3D-PCASL may provide additional value in the workup of dementia patients. (orig.)

  2. Semantic Neighborhood Effects for Abstract versus Concrete Words.

    Science.gov (United States)

    Danguecan, Ashley N; Buchanan, Lori

    2016-01-01

    Studies show that semantic effects may be task-specific, and thus, that semantic representations are flexible and dynamic. Such findings are critical to the development of a comprehensive theory of semantic processing in visual word recognition, which should arguably account for how semantic effects may vary by task. It has been suggested that semantic effects are more directly examined using tasks that explicitly require meaning processing relative to those for which meaning processing is not necessary (e.g., lexical decision task). The purpose of the present study was to chart the processing of concrete versus abstract words in the context of a global co-occurrence variable, semantic neighborhood density (SND), by comparing word recognition response times (RTs) across four tasks varying in explicit semantic demands: standard lexical decision task (with non-pronounceable non-words), go/no-go lexical decision task (with pronounceable non-words), progressive demasking task, and sentence relatedness task. The same experimental stimulus set was used across experiments and consisted of 44 concrete and 44 abstract words, with half of these being low SND, and half being high SND. In this way, concreteness and SND were manipulated in a factorial design using a number of visual word recognition tasks. A consistent RT pattern emerged across tasks, in which SND effects were found for abstract (but not necessarily concrete) words. Ultimately, these findings highlight the importance of studying interactive effects in word recognition, and suggest that linguistic associative information is particularly important for abstract words.

  3. Cardiovascular risk factors and dementia.

    Science.gov (United States)

    Fillit, Howard; Nash, David T; Rundek, Tatjana; Zuckerman, Andrea

    2008-06-01

    Dementias, such as Alzheimer's disease (AD) and vascular dementia, are disorders of aging populations and represent a significant economic burden. Evidence is accumulating to suggest that cardiovascular disease (CVD) risk factors may be instrumental in the development of dementia. The goal of this review was to discuss the relationship between specific CVD risk factors and dementia and how current treatment strategies for dementia should focus on reducing CVD risks. We conducted a review of the literature for the simultaneous presence of 2 major topics, cardiovascular risk factors and dementia (eg, AD). Special emphasis was placed on clinical outcome studies examining the effects of treatments of pharmacologically modifiable CVD risk factors on dementia and cognitive impairment. Lifestyle risk factors for CVD, such as obesity, lack of exercise, smoking, and certain psychosocial factors, have been associated with an increased risk of cognitive decline and dementia. Some evidence suggests that effectively managing these factors may prevent cognitive decline/dementia. Randomized, placebo-controlled trials of antihypertensive medications have found that such therapy may reduce the risk of cognitive decline, and limited data suggest a benefit for patients with AD. Some small open-label and randomized clinical trials of statins have observed positive effects on cognitive function; larger studies of statins in patients with AD are ongoing. Although more research is needed, current evidence indicates an association between CVD risk factors--such as hypertension, dyslipidemia, and diabetes mellitus--and cognitive decline/dementia. From a clinical perspective, these data further support the rationale for physicians to provide effective management of CVD risk factors and for patients to be compliant with such recommendations to possibly prevent cognitive decline/dementia.

  4. Reactive Kripke semantics

    CERN Document Server

    Gabbay, Dov M

    2013-01-01

    This text offers an extension to the traditional Kripke semantics for non-classical logics by adding the notion of reactivity. Reactive Kripke models change their accessibility relation as we progress in the evaluation process of formulas in the model. This feature makes the reactive Kripke semantics strictly stronger and more applicable than the traditional one. Here we investigate the properties and axiomatisations of this new and most effective semantics, and we offer a wide landscape of applications of the idea of reactivity. Applied topics include reactive automata, reactive grammars, rea

  5. Neuropsychiatric symptoms and quality of life in patients in the final phase of dementia.

    Science.gov (United States)

    Koopmans, Raymond T C M; van der Molen, Marloes; Raats, Monique; Ettema, Teake P

    2009-01-01

    To assess neuropsychiatric symptoms and quality of life in a group of patients in the final phase of dementia. All patients with dementia (n = 216) residing on dementia special care units of two Dutch nursing homes were included in the study provided they met the criteria for the final phase of dementia. Neuropsychiatric symptoms were assessed with the Neuropsychiatric Inventory Nursing Home version (NPI-NH) and the Cohen Mansfield Agitation Inventory (CMAI). Quality of life was assessed with the QUALIDEM. Of the 216 dementia patients 39 met the criteria for the final phase of dementia. The patients showed a specific pattern of behaviours with a high prevalence of apathy, agitation and behaviours that were mainly observed during morning care such as making strange noises, grabbing, performing repetitious mannerism, spitting, hitting, screaming and pushing. Overall quality of life of these patients in the final phase of dementia was moderate. In this small sample, patients in the final phase of dementia show specific behavioural problems, that mainly should be addressed with psychosocial interventions. (c) 2008 John Wiley & Sons, Ltd.

  6. Data Cleaning and Semantic Improvement in Biological Databases

    Directory of Open Access Journals (Sweden)

    Apiletti Daniele

    2006-12-01

    Full Text Available Public genomic and proteomic databases can be affected by a variety of errors. These errors may involve either the description or the meaning of data (namely, syntactic or semantic errors. We focus our analysis on the detection of semantic errors, in order to verify the accuracy of the stored information. In particular, we address the issue of data constraints and functional dependencies among attributes in a given relational database. Constraints and dependencies show semantics among attributes in a database schema and their knowledge may be exploited to improve data quality and integration in database design, and to perform query optimization and dimensional reduction.

  7. Hippocampal sclerosis dementia: An amnesic variant of frontotemporal degeneration

    Directory of Open Access Journals (Sweden)

    Chiadi U. Onyike

    Full Text Available ABSTRACT Objective: To describe characteristics of hippocampal sclerosis dementia. Methods: Convenience sample of Hippocampal sclerosis dementia (HSD recruited from the Johns Hopkins University Brain Resource Center. Twenty-four cases with post-mortem pathological diagnosis of hippocampal sclerosis dementia were reviewed for clinical characterization. Results: The cases showed atrophy and neuronal loss localized to the hippocampus, amygdala and entorrhinal cortex. The majority (79.2% had amnesia at illness onset, and many (54.2% showed abnormal conduct and psychiatric disorder. Nearly 42% presented with an amnesic state, and 37.5% presented with amnesia plus abnormal conduct and psychiatric disorder. All eventually developed a behavioral or psychiatric disorder. Disorientation, executive dysfunction, aphasia, agnosia and apraxia were uncommon at onset. Alzheimer disease (AD was the initial clinical diagnosis in 89% and the final clinical diagnosis in 75%. Diagnosis of frontotemporal dementia (FTD was uncommon (seen in 8%. Conclusion: HSD shows pathological characteristics of FTD and clinical features that mimic AD and overlap with FTD. The findings, placed in the context of earlier work, support the proposition that HSD belongs to the FTD family, where it may be identified as an amnesic variant.

  8. Hippocampal sclerosis dementia: an amnesic variant of frontotemporal degeneration

    Science.gov (United States)

    Onyike, Chiadi U.; Pletnikova, Olga; Sloane, Kelly L.; Sullivan, Campbell; Troncoso, Juan C.; Rabins, Peter V.

    2013-01-01

    OBJECTIVE To describe characteristics of hippocampal sclerosis dementia. METHODS Convenience sample of Hippocampal sclerosis dementia (HSD) recruited from the Johns Hopkins University Brain Resource Center. Twenty-four cases with post-mortem pathological diagnosis of hippocampal sclerosis dementia were reviewed for clinical characterization. RESULTS The cases showed atrophy and neuronal loss localized to the hippocampus, amygdala and entorrhinal cortex. The majority (79.2%) had amnesia at illness onset, and many (54.2%) showed abnormal conduct and psychiatric disorder. Nearly 42% presented with an amnesic state, and 37.5% presented with amnesia plus abnormal conduct and psychiatric disorder. All eventually developed a behavioral or psychiatric disorder. Disorientation, executive dysfunction, aphasia, agnosia and apraxia were uncommon at onset. Alzheimer disease (AD) was the initial clinical diagnosis in 89% and the final clinical diagnosis in 75%. Diagnosis of frontotemporal dementia (FTD) was uncommon (seen in 8%). CONCLUSION HSD shows pathological characteristics of FTD and clinical features that mimic AD and overlap with FTD. The findings, placed in the context of earlier work, support the proposition that HSD belongs to the FTD family, where it may be identified as an amnesic variant. PMID:24363834

  9. The Cross-Cultural Dementia Screening (CCD): A new neuropsychological screening instrument for dementia in elderly immigrants.

    Science.gov (United States)

    Goudsmit, Miriam; Uysal-Bozkir, Özgül; Parlevliet, Juliette L; van Campen, Jos P C M; de Rooij, Sophia E; Schmand, Ben

    2017-03-01

    Currently, approximately 3.9% of the European population are non-EU citizens, and a large part of these people are from "non-Western" societies, such as Turkey and Morocco. For various reasons, the incidence of dementia in this group is expected to increase. However, cognitive testing is challenging due to language barriers and low education and/or illiteracy. The newly developed Cross-Cultural Dementia Screening (CCD) can be administered without an interpreter. It contains three subtests that assess memory, mental speed, and executive function. We hypothesized the CCD to be a culture-fair test that could discriminate between demented patients and cognitively healthy controls. To test this hypothesis, 54 patients who had probable dementia were recruited via memory clinics. Controls (N = 1625) were recruited via their general practitioners. All patients and controls were aged 55 years and older and of six different self-defined ethnicities (Dutch, Turkish, Moroccan-Arabic, Moroccan-Berber, Surinamese-Creole, and Surinamese-Hindustani). Exclusion criteria included current or previous conditions that affect cognitive functioning. There were performance differences between the ethnic groups, but these disappeared after correcting for age and education differences between the groups, which supports our central hypothesis that the CCD is a culture-fair test. Receiver-operating characteristic (ROC) and logistic regression analyses showed that the CCD has high predictive validity for dementia (sensitivity: 85%; specificity: 89%). The CCD is a sensitive and culture-fair neuropsychological instrument for dementia screening in low-educated immigrant populations.

  10. Semantic richness and word learning in children with autism spectrum disorder.

    Science.gov (United States)

    Gladfelter, Allison; Goffman, Lisa

    2018-03-01

    Semantically rich learning contexts facilitate semantic, phonological, and articulatory aspects of word learning in children with typical development (TD). However, because children with autism spectrum disorder (ASD) show differences at each of these processing levels, it is unclear whether they will benefit from semantic cues in the same manner as their typical peers. The goal of this study was to track how the inclusion of rich, sparse, or no semantic cues influences semantic, phonological, and articulatory aspects of word learning in children with ASD and TD over time. Twenty-four school-aged children (12 in each group), matched on expressive vocabulary, participated in an extended word learning paradigm. Performance on five measures of learning (referent identification, confrontation naming, defining, phonetic accuracy, and speech motor stability) were tracked across three sessions approximately one week apart to assess the influence of semantic richness on extended learning. Results indicate that children with ASD benefit from semantically rich learning contexts similarly to their peers with TD; however, one key difference between the two groups emerged - the children with ASD showed heightened shifts in speech motor stability. These findings offer insights into common learning mechanisms in children with ASD and TD, as well as pointing to a potentially distinct speech motor learning trajectory in children with ASD, providing a window into the emergence of stereotypic vocalizations in these children. © 2017 John Wiley & Sons Ltd.

  11. Ontology based heterogeneous materials database integration and semantic query

    Science.gov (United States)

    Zhao, Shuai; Qian, Quan

    2017-10-01

    Materials digital data, high throughput experiments and high throughput computations are regarded as three key pillars of materials genome initiatives. With the fast growth of materials data, the integration and sharing of data is very urgent, that has gradually become a hot topic of materials informatics. Due to the lack of semantic description, it is difficult to integrate data deeply in semantic level when adopting the conventional heterogeneous database integration approaches such as federal database or data warehouse. In this paper, a semantic integration method is proposed to create the semantic ontology by extracting the database schema semi-automatically. Other heterogeneous databases are integrated to the ontology by means of relational algebra and the rooted graph. Based on integrated ontology, semantic query can be done using SPARQL. During the experiments, two world famous First Principle Computational databases, OQMD and Materials Project are used as the integration targets, which show the availability and effectiveness of our method.

  12. Hyperthyroid dementia: clinicoradiological findings and response to treatment.

    Science.gov (United States)

    Fukui, T; Hasegawa, Y; Takenaka, H

    2001-02-15

    Dementia associated with hyperthyroidism is less well documented than is hypothyroid dementia. Therapeutic response of hyperthyroid dementia and associated cerebral circulatory and/or metabolic abnormalities has not been elucidated. We described a patient with hyperthyroid dementia and clinicoradiological response to treatment. Single photon emission computed tomographic (SPECT) study was repeated and analyzed semiquantitatively. A 67-year-old man experienced progressive impairments of attention, memory, constructive skills and behavior as well as hand tremor and weight loss of two-year duration. Laboratory findings were compatible with Graves' disease. The initial SPECT showed diffuse tracer uptake defect with an accentuation in the bilateral temporoparietal regions. Clinical and SPECT findings both suggested concurrent "possible" Alzheimer's disease. However, initial treatment with a beta-blocker improved behavior and attention-related cognitive functions as well as tracer uptake in the frontal lobes. Subsequent treatment with additional methimazole then improved memory and constructive abilities when a euthyroid state was established. Uptake defect in the temporoparietal regions also responded gradually to the medication. We suggest that the present patient represent hyperthyroid dementia, which responds favorably to treatment with regard to clinical symptoms and SPECT findings. We also suggest that thyroid function be measured in patients with "possible" Alzheimer's disease because treatable hyperthyroid dementia may not be identified.

  13. Dementia and driving

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000028.htm Dementia and driving To use the sharing features on ... please enable JavaScript. If your loved one has dementia , deciding when they can no longer drive may ...

  14. ABO Blood Group and Dementia Risk--A Scandinavian Record-Linkage Study

    DEFF Research Database (Denmark)

    Vasan, Senthil K; Rostgaard, Klaus; Ullum, Henrik

    2015-01-01

    ,615 cases of Alzheimer's disease, 1,842 cases of vascular dementia, and 9,091 cases of unspecified dementia. Overall, our study showed no association between ABO blood group and risk of Alzheimer's disease, vascular dementia or unspecified dementia. This was also true when analyses were restricted to donors......BACKGROUND: Dementia includes a group of neuro-degenerative disorders characterized by varying degrees of cognitive impairment. Recent data indicates that blood group AB is associated with impaired cognition in elderly patients. To date there are no large-scale studies that have examined...... the relationship between ABO blood group and dementia-related disorders in detail. METHODS: We used data from the SCANDAT2 database that contains information on over 1.6 million blood donors from 1968 in Sweden and 1981 from Denmark. The database was linked with health outcomes data from nationwide patient...

  15. Trajectories of Behavioural Disturbances Across Dementia Types.

    Science.gov (United States)

    Linds, Alexandra B; Kirstein, Alana B; Freedman, Morris; Verhoeff, Nicolaas P L G; Wolf, Uri; Chow, Tiffany W

    2015-11-01

    To replicate a previous finding that the trajectory of the Neuropsychiatric Inventory (NPI) shifts in the sixth year of behavioural variant frontotemporal dementia (bvFTD). We evaluated longitudinal tracking with both the Frontal Behavioural Inventory (FBI) and NPI, comparing bvFTD against other dementias. Chart reviews over two to five years for patients with bvFTD (n=30), primary progressive aphasia (PPA, n=13) and Alzheimer's disease (AD, n=118) at an urban Canadian tertiary clinic specializing in dementia. Linear regressions of the longitudinal data tested predictors of annualized rates of change (ROC) in NPI and FBI total and subscales for apathy and disinhibition among dementia groups. The mode of the overall sample for the most advanced duration of illness observed was 5 years, with the median at 7 years. We did not find a crescendo-decrescendo pattern in scores although, for bvFTD and AD, high initial scores correlated with ensuing downward ROCs on the NPI and FBI. Educational level showed an influence on disinhibition ROCs. The FBI was no more revealing than the NPI for apathy and disinhibition scores in these dementias. A cognitive reserve effect on behavioural disturbance was supported but it may take longer than our 4 years of observing the clinical sample to record inflection points in the behavioural and psychiatric symptoms seen in bvFTD. The current data only imply that both apathy and disinhibition will diminish over the course of dementia.

  16. Semantic web for dummies

    CERN Document Server

    Pollock, Jeffrey T

    2009-01-01

    Semantic Web technology is already changing how we interact with data on the Web. By connecting random information on the Internet in new ways, Web 3.0, as it is sometimes called, represents an exciting online evolution. Whether you're a consumer doing research online, a business owner who wants to offer your customers the most useful Web site, or an IT manager eager to understand Semantic Web solutions, Semantic Web For Dummies is the place to start! It will help you:Know how the typical Internet user will recognize the effects of the Semantic WebExplore all the benefits the data Web offers t

  17. Age-related differences in recall for words using semantics and prosody.

    Science.gov (United States)

    Sober, Jonathan D; VanWormer, Lisa A; Arruda, James E

    2016-01-01

    The positivity effect is a developmental shift seen in older adults to be increasingly influenced by positive information in areas such as memory, attention, and decision-making. This study is the first to examine the age-related differences of the positivity effect for emotional prosody. Participants heard a factorial combination of words that were semantically positive or negative said with either positive or negative intonation. Results showed a semantic positivity effect for older adults, and a prosody positivity effect for younger adults. Additionally, older adults showed a significant decrease in recall for semantically negative words said in an incongruent prosodically positive tone.

  18. The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

    Science.gov (United States)

    Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

    2010-01-01

    The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Subjects engaged in two picture judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line orientation judgments, engaging in semantic categorization judgments increased the proportion of item ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture judgment task manipulations. These results thus demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance. PMID:21058880

  19. Depression and the risk for dementia.

    Science.gov (United States)

    Kessing, Lars Vedel

    2012-11-01

    Depression is associated with increased risk of subsequent development of dementia; however, the nature of the association is still poorly understood. The purpose of the review was based on recent studies to discuss whether depression is a prodromal state of dementia or an independent risk factor for dementia, as well as to discuss how the type of depression, the type of dementia, and antidepressant treatment influence the association. Findings from recent studies suggest that some forms of depressive illness, for example early-onset depression before age 65 years and recurrent depression, may constitute long-term risk factors for development of dementia, whereas the onset of more recent depressive symptoms may reflect a prodromal phase of dementia. It is not clear whether specific subtypes of depression correspond to specific types of dementia. Recent studies suggest that long-term treatment with antidepressants may decrease the risk of developing some types of dementia, depending on the type of depressive disorder. This review has shown that the type of depression and dementia, as well as the effect of drug treatment, has to be considered to improve knowledge on the association between depression and dementia.

  20. Clustering semantics for hypermedia presentation

    NARCIS (Netherlands)

    Alberink, M.J.; Rutledge, L.W.; Hardman, H.L.; Veenstra, M.J.A.

    2004-01-01

    Semantic annotations of media repositories make relationships among the stored media and relevant concepts explicit. However, these relationships and the media they join are not directly presentable as hypermedia. Previous work shows how clustering over the annotations in the repositories can

  1. Incidental Vocabulary Learning: A Semantic Field Approach

    Directory of Open Access Journals (Sweden)

    Parvaneh Khosravizadeh

    2011-10-01

    Full Text Available

    This study is an attempt to explore the difference between acquiring new words with different semantic fields to which they belong. In other words, the purpose of this study is to scrutinize the contribution of semantic field theory in learning new vocabulary items in an EFL setting. Thirty-eight students of three different levels of education took part in this research. They were exposed to some new words from four different semantic fields, and then they were tested on their acquisition of the words meaning. This exposure was through reading texts and the aim of reading was just comprehension, therefore the words were acquired incidentally. The outcome showed significant differences between groups with different levels of education regarding retention of words from different semantic fields.

  2. Putting semantics into the semantic web: how well can it capture biology?

    Science.gov (United States)

    Kazic, Toni

    2006-01-01

    Could the Semantic Web work for computations of biological interest in the way it's intended to work for movie reviews and commercial transactions? It would be wonderful if it could, so it's worth looking to see if its infrastructure is adequate to the job. The technologies of the Semantic Web make several crucial assumptions. I examine those assumptions; argue that they create significant problems; and suggest some alternative ways of achieving the Semantic Web's goals for biology.

  3. Diagnostic and prognostic role of semantic processing in preclinical Alzheimer's disease.

    Science.gov (United States)

    Venneri, Annalena; Jahn-Carta, Caroline; Marco, Matteo De; Quaranta, Davide; Marra, Camillo

    2018-06-13

    Relatively spared during most of the timeline of normal aging, semantic memory shows a subtle yet measurable decline even during the pre-clinical stage of Alzheimer's disease. This decline is thought to reflect early neurofibrillary changes and impairment is detectable using tests of language relying on lexical-semantic abilities. A promising approach is the characterization of semantic parameters such as typicality and age of acquisition of words, and propositional density from verbal output. Seminal research like the Nun Study or the analysis of the linguistic decline of famous writers and politicians later diagnosed with Alzheimer's disease supports the early diagnostic value of semantic processing and semantic memory. Moreover, measures of these skills may play an important role for the prognosis of patients with mild cognitive impairment.

  4. The facilitation effect of associative and semantic relatedness in word recognition

    Directory of Open Access Journals (Sweden)

    Jakić Milena

    2011-01-01

    Full Text Available In this study we addressed three issues concerning semantic and associative relatedness between two words and how they prime each other. The first issue is whether there is a priming effect of semantic relatedness over and above the effect of associative relatedness. The second issue is how difference in semantic overlap between two words affects priming. In order to specify the semantic overlap we introduce five relation types that differ in number of common semantic components. Three relation types (synonyms, antonyms and hyponyms represent semantic relatedness while two relation types represent associative relatedness, with negligible or no semantic relatedness. Finally, the third issue addressed in this study is whether there is a symmetric priming effect if we swap the position of prime and target, i.e. whether the direction of relatedness between two words affects priming. In two lexical decision experiments we presented five types of word pairs. In both experiments we obtained stronger facilitation for pairs that were both semantically and associatively related. Closer inspection showed that larger semantic overlap between words is paralleled by greater facilitation effect. The effects did not change when prime and target swap their position, indicating that the observed facilitation effects are symmetrical. This outcome complies with predictions of distributed models of memory.

  5. Requirements-level semantics and model checking of object-oriented statecharts

    NARCIS (Netherlands)

    Eshuis, H.; Jansen, D.N.; Wieringa, Roelf J.

    2002-01-01

    In this paper we define a requirements-level execution semantics for object-oriented statecharts and show how properties of a system specified by these statecharts can be model checked using tool support for model checkers. Our execution semantics is requirements-level because it uses the perfect

  6. What do children need to know about dementia? The perspectives of children and people with personal experience of dementia.

    Science.gov (United States)

    Baker, Jess R; Jeon, Yun-Hee; Goodenough, Belinda; Low, Lee-Fay; Bryden, Christine; Hutchinson, Karen; Richards, Laura

    2017-10-02

    The vision for dementia-friendly communities is challenged by limited public awareness and stigma about dementia. The study aim was to elicit stakeholder priorities for the message content of an education program to improve dementia awareness among youth; specifically, what do children need to know about dementia? A qualitative inquiry using interviews and focus groups was used. Purposive sampling achieved maximum variation in dementia experience and participant characteristics. Focus groups with Scouts in the community aged 9-12 years old (n = 22) used innovative techniques to explore children's attitudes towards people with dementia. Participants with personal experience of dementia were five people with early-stage dementia; 12 adult primary carers; four non-primary carers; and six grandchildren of a person with dementia. They were asked what is important for children to understand about dementia and what attitudes they may like an education program to confer. Content analysis was performed using NVivo10. Strong themes to emerge were that children need to know the whole truth about dementia; that individuals with dementia are "still people," that it is "not the fault" of the person with dementia; and that dementia is different and typically unpredictable for everyone. Discussions also indicated a need to educate children about ways to relate to a person with dementia, and to appreciate "positives" within a relationship. Children are our future citizens. Developing an education program for children with this message content may be fundamental to de-stigmatizing dementia and laying the foundation to dementia-friendly communities.

  7. Team-Based Interprofessional Competency Training for Dementia Screening and Management.

    Science.gov (United States)

    Tan, Zaldy S; Damron-Rodriguez, JoAnn; Cadogan, Mary; Gans, Daphna; Price, Rachel M; Merkin, Sharon S; Jennings, Lee; Schickedanz, Heather; Shimomura, Sam; Osterweil, Dan; Chodosh, Joshua

    2017-01-01

    As many as 50% of people satisfying diagnostic criteria for dementia are undiagnosed. A team-based training program for dementia screening and management was developed targeting four professions (medicine, nursing, pharmacy, social work) whose scope of practice involves dementia care. An interprofessional group of 10 faculty members was trained to facilitate four interactive competency stations on dementia screening, differential diagnoses, dementia management and team care planning, and screening for and managing caregiver stress. Registrants were organized into teams of five members, with at least one member of each profession per team. The teams rotated through all stations, completing assigned tasks through interprofessional collaboration. A total of 117 professionals (51 physicians, 11 nurses, 20 pharmacists, 24 social workers, 11 others) successfully completed the program. Change scores showed significant improvements in overall competence in dementia assessment and intervention (very low = 1; very high = 5; average change 1.12, P managing medication (average change 0.86, P team-based interprofessional competency training is a team teaching model that can be used to enhance competency in dementia screening and management in medical, nursing, pharmacy, and social work practitioners. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

  8. Language and culture modulate online semantic processing.

    Science.gov (United States)

    Ellis, Ceri; Kuipers, Jan R; Thierry, Guillaume; Lovett, Victoria; Turnbull, Oliver; Jones, Manon W

    2015-10-01

    Language has been shown to influence non-linguistic cognitive operations such as colour perception, object categorization and motion event perception. Here, we show that language also modulates higher level processing, such as semantic knowledge. Using event-related brain potentials, we show that highly fluent Welsh-English bilinguals require significantly less processing effort when reading sentences in Welsh which contain factually correct information about Wales, than when reading sentences containing the same information presented in English. Crucially, culturally irrelevant information was processed similarly in both Welsh and English. Our findings show that even in highly proficient bilinguals, language interacts with factors associated with personal identity, such as culture, to modulate online semantic processing. © The Author (2015). Published by Oxford University Press.

  9. Person- and place-selective neural substrates for entity-specific semantic access.

    Science.gov (United States)

    Fairhall, Scott L; Anzellotti, Stefano; Ubaldi, Silvia; Caramazza, Alfonso

    2014-07-01

    Object-category has a pronounced effect on the representation of objects in higher level visual cortex. However, the influence of category on semantic/conceptual processes is less well characterized. In the present study, we conduct 2 fMRI experiments to investigate the semantic processing of information specific to individual people and places (entities). First, during picture presentation, we determined which brain regions show category-selective increases during access to entity-specific semantic information (i.e., nationality) in comparison to general-category discrimination (person vs. place). In the second experiment, we presented either words or pictures to assess the independence of entity-specific category-selective semantic representations from the processes used to access those representations. Convergent results from these 2 experiments show that brain regions exhibiting a category-selective increase during entity-specific semantic access are the same as those that show a supramodal (word/picture) category-selective response during the same task. These responses were different from classical "perceptual" category-selective responses and were evident in the medial precuneus for people and in the retrosplenial complex as well as anterior/superior sections of the transverse occipital sulcus and parahippocampal gyrus for places. These results reveal the pervasive influence of object-category in cortical organization, which extends to aspects of semantic knowledge arbitrarily related to physical/perceptual properties. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Towards Compatible and Interderivable Semantic Specifications for the Scheme Programming Language, Part I: Denotational Semantics, Natural Semantics, and Abstract Machines

    DEFF Research Database (Denmark)

    Danvy, Olivier

    2008-01-01

    We derive two big-step abstract machines, a natural semantics, and the valuation function of a denotational semantics based on the small-step abstract machine for Core Scheme presented by Clinger at PLDI'98. Starting from a functional implementation of this small-step abstract machine, (1) we fuse...... its transition function with its driver loop, obtaining the functional implementation of a big-step abstract machine; (2) we adjust this big-step abstract machine so that it is in defunctionalized form, obtaining the functional implementation of a second big-step abstract machine; (3) we...... refunctionalize this adjusted abstract machine, obtaining the functional implementation of a natural semantics in continuation style; and (4) we closure-unconvert this natural semantics, obtaining a compositional continuation-passing evaluation function which we identify as the functional implementation...

  11. Temporal Representation in Semantic Graphs

    Energy Technology Data Exchange (ETDEWEB)

    Levandoski, J J; Abdulla, G M

    2007-08-07

    A wide range of knowledge discovery and analysis applications, ranging from business to biological, make use of semantic graphs when modeling relationships and concepts. Most of the semantic graphs used in these applications are assumed to be static pieces of information, meaning temporal evolution of concepts and relationships are not taken into account. Guided by the need for more advanced semantic graph queries involving temporal concepts, this paper surveys the existing work involving temporal representations in semantic graphs.

  12. The Interaction between Semantic Representation and Episodic Memory.

    Science.gov (United States)

    Fang, Jing; Rüther, Naima; Bellebaum, Christian; Wiskott, Laurenz; Cheng, Sen

    2018-02-01

    The experimental evidence on the interrelation between episodic memory and semantic memory is inconclusive. Are they independent systems, different aspects of a single system, or separate but strongly interacting systems? Here, we propose a computational role for the interaction between the semantic and episodic systems that might help resolve this debate. We hypothesize that episodic memories are represented as sequences of activation patterns. These patterns are the output of a semantic representational network that compresses the high-dimensional sensory input. We show quantitatively that the accuracy of episodic memory crucially depends on the quality of the semantic representation. We compare two types of semantic representations: appropriate representations, which means that the representation is used to store input sequences that are of the same type as those that it was trained on, and inappropriate representations, which means that stored inputs differ from the training data. Retrieval accuracy is higher for appropriate representations because the encoded sequences are less divergent than those encoded with inappropriate representations. Consistent with our model prediction, we found that human subjects remember some aspects of episodes significantly more accurately if they had previously been familiarized with the objects occurring in the episode, as compared to episodes involving unfamiliar objects. We thus conclude that the interaction with the semantic system plays an important role for episodic memory.

  13. Semantic Web Technologies for the Adaptive Web

    DEFF Research Database (Denmark)

    Dolog, Peter; Nejdl, Wolfgang

    2007-01-01

    Ontologies and reasoning are the key terms brought into focus by the semantic web community. Formal representation of ontologies in a common data model on the web can be taken as a foundation for adaptive web technologies as well. This chapter describes how ontologies shared on the semantic web...... provide conceptualization for the links which are a main vehicle to access information on the web. The subject domain ontologies serve as constraints for generating only those links which are relevant for the domain a user is currently interested in. Furthermore, user model ontologies provide additional...... means for deciding which links to show, annotate, hide, generate, and reorder. The semantic web technologies provide means to formalize the domain ontologies and metadata created from them. The formalization enables reasoning for personalization decisions. This chapter describes which components...

  14. Enhancing biomedical text summarization using semantic relation extraction.

    Directory of Open Access Journals (Sweden)

    Yue Shang

    Full Text Available Automatic text summarization for a biomedical concept can help researchers to get the key points of a certain topic from large amount of biomedical literature efficiently. In this paper, we present a method for generating text summary for a given biomedical concept, e.g., H1N1 disease, from multiple documents based on semantic relation extraction. Our approach includes three stages: 1 We extract semantic relations in each sentence using the semantic knowledge representation tool SemRep. 2 We develop a relation-level retrieval method to select the relations most relevant to each query concept and visualize them in a graphic representation. 3 For relations in the relevant set, we extract informative sentences that can interpret them from the document collection to generate text summary using an information retrieval based method. Our major focus in this work is to investigate the contribution of semantic relation extraction to the task of biomedical text summarization. The experimental results on summarization for a set of diseases show that the introduction of semantic knowledge improves the performance and our results are better than the MEAD system, a well-known tool for text summarization.

  15. Enhancing biomedical text summarization using semantic relation extraction.

    Science.gov (United States)

    Shang, Yue; Li, Yanpeng; Lin, Hongfei; Yang, Zhihao

    2011-01-01

    Automatic text summarization for a biomedical concept can help researchers to get the key points of a certain topic from large amount of biomedical literature efficiently. In this paper, we present a method for generating text summary for a given biomedical concept, e.g., H1N1 disease, from multiple documents based on semantic relation extraction. Our approach includes three stages: 1) We extract semantic relations in each sentence using the semantic knowledge representation tool SemRep. 2) We develop a relation-level retrieval method to select the relations most relevant to each query concept and visualize them in a graphic representation. 3) For relations in the relevant set, we extract informative sentences that can interpret them from the document collection to generate text summary using an information retrieval based method. Our major focus in this work is to investigate the contribution of semantic relation extraction to the task of biomedical text summarization. The experimental results on summarization for a set of diseases show that the introduction of semantic knowledge improves the performance and our results are better than the MEAD system, a well-known tool for text summarization.

  16. A Simple Semantics and Static Analysis for Stack Inspection

    Directory of Open Access Journals (Sweden)

    Anindya Banerjee

    2013-09-01

    Full Text Available The Java virtual machine and the .NET common language runtime feature an access control mechanism specified operationally in terms of run-time stack inspection. We give a denotational semantics in "eager" form, and show that it is equivalent to the "lazy" semantics using stack inspection. We give a static analysis of safety, i.e., the absence of security errors, that is simpler than previous proposals. We identify several program transformations that can be used to remove run-time checks. We give complete, detailed proofs for safety of the analysis and for the transformations, exploiting compositionality of the eager semantics.

  17. Prevalence and management of pain, by race and dementia among nursing home residents: United States, 2004.

    Science.gov (United States)

    Sengupta, Manisha; Bercovitz, Anita; Harris-Kojetin, Lauren D

    2010-03-01

    Data from the National Nursing Home Survey, 2004. About one-quarter of all nursing home residents reported or showed signs of pain. Nonwhite residents and residents with dementia were less likely to report or show signs of pain compared with white residents and residents without dementia. Nonwhite residents with dementia were least likely, and white residents without dementia were most likely to report or show signs of pain. Forty-four percent of nursing home residents with pain received neither standing orders for pain medication nor special services for pain management (i.e., appropriate pain management). Among residents with dementia and pain, nonwhite residents were more likely than white residents to lack appropriate pain management.

  18. Differential Classification of Dementia

    Directory of Open Access Journals (Sweden)

    E. Mohr

    1995-01-01

    Full Text Available In the absence of biological markers, dementia classification remains complex both in terms of characterization as well as early detection of the presence or absence of dementing symptoms, particularly in diseases with possible secondary dementia. An empirical, statistical approach using neuropsychological measures was therefore developed to distinguish demented from non-demented patients and to identify differential patterns of cognitive dysfunction in neurodegenerative disease. Age-scaled neurobehavioral test results (Wechsler Adult Intelligence Scale—Revised and Wechsler Memory Scale from Alzheimer's (AD and Huntington's (HD patients, matched for intellectual disability, as well as normal controls were used to derive a classification formula. Stepwise discriminant analysis accurately (99% correct distinguished controls from demented patients, and separated the two patient groups (79% correct. Variables discriminating between HD and AD patient groups consisted of complex psychomotor tasks, visuospatial function, attention and memory. The reliability of the classification formula was demonstrated with a new, independent sample of AD and HD patients which yielded virtually identical results (classification accuracy for dementia: 96%; AD versus HD: 78%. To validate the formula, the discriminant function was applied to Parkinson's (PD patients, 38% of whom were classified as demented. The validity of the classification was demonstrated by significant PD subgroup differences on measures of dementia not included in the discriminant function. Moreover, a majority of demented PD patients (65% were classified as having an HD-like pattern of cognitive deficits, in line with previous reports of the subcortical nature of PD dementia. This approach may thus be useful in classifying presence or absence of dementia and in discriminating between dementia subtypes in cases of secondary or coincidental dementia.

  19. Cerebral imaging and dementia

    International Nuclear Information System (INIS)

    Rascol, A.; Celsis, P.; Berry, I.

    1989-01-01

    Modern imaging techniques undoubtedly are of value when applied to the study of dementia. This value, however, varies with the technique utilized, and one must distinguish between acquired and potential knowledge. Morphological imaging with computerized tomography or magnetic resonance detects or confirms certain causes of dementia (tumours, lacunae, hydrocephalus with normal CSF pressure), but it is still not sensitive and specific enough to be very useful in primary dementias. Functional imaging (essentially with emission tomography) has already provided interesting data in the study of degenerative dementia (correlations with neuropsychology, subtyping), but what is most promising is its possibilities in the physiopathological approach of the disease [fr

  20. Cerebral imaging and dementia

    Energy Technology Data Exchange (ETDEWEB)

    Rascol, A.; Celsis, P.; Berry, I.

    1989-02-01

    Modern imaging techniques undoubtedly are of value when applied to the study of dementia. This value, however, varies with the technique utilized, and one must distinguish between acquired and potential knowledge. Morphological imaging with computerized tomography or magnetic resonance detects or confirms certain causes of dementia (tumours, lacunae, hydrocephalus with normal CSF pressure), but it is still not sensitive and specific enough to be very useful in primary dementias. Functional imaging (essentially with emission tomography) has already provided interesting data in the study of degenerative dementia (correlations with neuropsychology, subtyping), but what is most promising is its possibilities in the physiopathological approach of the disease.

  1. SemantEco: a semantically powered modular architecture for integrating distributed environmental and ecological data

    Science.gov (United States)

    Patton, Evan W.; Seyed, Patrice; Wang, Ping; Fu, Linyun; Dein, F. Joshua; Bristol, R. Sky; McGuinness, Deborah L.

    2014-01-01

    We aim to inform the development of decision support tools for resource managers who need to examine large complex ecosystems and make recommendations in the face of many tradeoffs and conflicting drivers. We take a semantic technology approach, leveraging background ontologies and the growing body of linked open data. In previous work, we designed and implemented a semantically enabled environmental monitoring framework called SemantEco and used it to build a water quality portal named SemantAqua. Our previous system included foundational ontologies to support environmental regulation violations and relevant human health effects. In this work, we discuss SemantEco’s new architecture that supports modular extensions and makes it easier to support additional domains. Our enhanced framework includes foundational ontologies to support modeling of wildlife observation and wildlife health impacts, thereby enabling deeper and broader support for more holistically examining the effects of environmental pollution on ecosystems. We conclude with a discussion of how, through the application of semantic technologies, modular designs will make it easier for resource managers to bring in new sources of data to support more complex use cases.

  2. Comparison of Alzheimer's disease with vascular dementia and non-dementia using specific voxel-based Z score maps

    International Nuclear Information System (INIS)

    Ishii, Shirou; Shishido, Fumio; Miyajima, Masayuki; Sakuma, Koutarou; Shigihara, Takeshi; Tameta, Tadanobu; Miyazaki, Makoto; Kuroda, Hiroshi

    2009-01-01

    We investigated the ability to discriminate between Alzheimer's disease (AD) and vascular dementia (VaD), and between AD and non-dementia using the program ''easy Z score imaging system'' (eZIS) developed by Matsuda et al., for the diagnosis of very early AD. Of 201 patients, we investigated 12 patients with AD, 10 with VaD, and 9 with non-dementia, who underwent brain perfusion single-photon emission computed tomography by technetium-99m ethyl cysteinate dimer ( 99m Tc-ECD) between February 2005 and September 2006. The sensitivity and specificity of the indicators of specific volume of interest (VOI) analysis, namely, severity, extent, and ratio were evaluated for the distinction of AD from VaD and non-dementia. There was a significant difference in all the criteria for severity, extent, and ratio between AD and non-dementia cases and in the ratio between AD and VaD. Between AD and non-dementia, the sensitivity and specificity of severity were 100% and 45%, respectively, using the cutoff value of 1.19. When using the cutoff value of 14.2 for extent, the sensitivity and specificity were both 100%. Using the cutoff value of 2.22 for ratio, the sensitivity of 42% and specificity of 100% were demonstrated. When comparing AD with VaD, using the cutoff value of 2.22 for ratio, the sensitivity and specificity were 42% and 100%, respectively. Using the cutoff value of 1.5 for ratio, the sensitivity and specificity between AD and VaD were 92% and 80%, respectively, thereby showing the best results. The specific VOI analysis program of AD using specific voxel-based Z score maps is not influenced by interobserver differences among radiologists and is useful to discriminate AD from VaD and non-dementia. However, the setting of the cutoff value at each institution and comparison with original and eZIS images are suggested to distinguish better AD from VaD. (author)

  3. Semantic Web Primer

    NARCIS (Netherlands)

    Antoniou, Grigoris; Harmelen, Frank van

    2004-01-01

    The development of the Semantic Web, with machine-readable content, has the potential to revolutionize the World Wide Web and its use. A Semantic Web Primer provides an introduction and guide to this still emerging field, describing its key ideas, languages, and technologies. Suitable for use as a

  4. Hierarchical Semantic Model of Geovideo

    Directory of Open Access Journals (Sweden)

    XIE Xiao

    2015-05-01

    Full Text Available The public security incidents were getting increasingly challenging with regard to their new features, including multi-scale mobility, multistage dynamic evolution, as well as spatiotemporal concurrency and uncertainty in the complex urban environment. However, the existing video models, which were used/designed for independent archive or local analysis of surveillance video, have seriously inhibited emergency response to the urgent requirements.Aiming at the explicit representation of change mechanism in video, the paper proposed a novel hierarchical geovideo semantic model using UML. This model was characterized by the hierarchical representation of both data structure and semantics based on the change-oriented three domains (feature domain, process domain and event domain instead of overall semantic description of video streaming; combining both geographical semantics and video content semantics, in support of global semantic association between multiple geovideo data. The public security incidents by video surveillance are inspected as an example to illustrate the validity of this model.

  5. Mapping the Structure of Semantic Memory

    Science.gov (United States)

    Morais, Ana Sofia; Olsson, Henrik; Schooler, Lael J.

    2013-01-01

    Aggregating snippets from the semantic memories of many individuals may not yield a good map of an individual's semantic memory. The authors analyze the structure of semantic networks that they sampled from individuals through a new snowball sampling paradigm during approximately 6 weeks of 1-hr daily sessions. The semantic networks of individuals…

  6. Increased Physical Fitness Is Associated with Higher Executive Functioning in People with Dementia

    Directory of Open Access Journals (Sweden)

    Alice Hollamby

    2017-12-01

    Full Text Available Physical fitness (PF has been associated with improved cognition in older age, but less is known about its effects on different cognitive domains in individuals diagnosed with dementia. We explored the associations between PF and cognitive performance in 40 healthy elderly and 30 individuals with dementia. Participants completed a battery of standardized cognitive tests (Mini-Mental State Exam, Verbal Fluency, Prospective and Retrospective Memory Questionnaire, Clock Drawing, and California Verbal Learning Test and were classified into high versus low levels of PF based on their score on the Physical Fitness Questionnaire. Analyses took into account age, gender, education, occupation, head injury, Internet use, brain training, and past levels of exercise and revealed overall benefits of PF, in particular for the people with dementia. Discriminant analysis showed high accuracy of reclassification, with most errors being due to the misclassification of dementia cases as healthy when they had high PF. The first discriminant function accounted for 83% of the variance. Using individual estimates of this function, which reflected global cognitive performance, confirmed the beneficial role of PF in dementia, even when taking into account age, past level of exercise, and the number of years since the dementia diagnosis. Finally, univariate analyses confirmed the differential sensitivity of the cognitive tests, with MMSE and clock drawing showing reliable interaction effects. This work shows that PF is associated with a reduced level of cognitive deterioration expected with dementia, especially in executive functioning and provides empirical support for the cognitive benefits of interventions promoting PF for individuals with dementia.

  7. Learning Document Semantic Representation with Hybrid Deep Belief Network

    Directory of Open Access Journals (Sweden)

    Yan Yan

    2015-01-01

    it is also an effective way to remove noise from the different document representation type; the DBN can enhance extract abstract of the document in depth, making the model learn sufficient semantic representation. At the same time, we explore different input strategies for semantic distributed representation. Experimental results show that our model using the word embedding instead of single word has better performance.

  8. A review of ethical issues in dementia.

    Science.gov (United States)

    Johnson, Rebecca A; Karlawish, Jason

    2015-10-01

    Dementia raises many ethical issues. The present review, taking note of the fact that the stages of dementia raise distinct ethical issues, focuses on three issues associated with stages of dementia's progression: (1) how the emergence of preclinical and asymptomatic but at-risk categories for dementia creates complex questions about preventive measures, risk disclosure, and protection from stigma and discrimination; (2) how despite efforts at dementia prevention, important research continues to investigate ways to alleviate clinical dementia's symptoms, and requires additional human subjects protections to ethically enroll persons with dementia; and (3) how in spite of research and prevention efforts, persons continue to need to live with dementia. This review highlights two major themes. First is how expanding the boundaries of dementias such as Alzheimer's to include asymptomatic but at-risk persons generate new ethical questions. One promising way to address these questions is to take an integrated approach to dementia ethics, which can include incorporating ethics-related data collection into the design of a dementia research study itself. Second is the interdisciplinary nature of ethical questions related to dementia, from health policy questions about insurance coverage for long-term care to political questions about voting, driving, and other civic rights and privileges to economic questions about balancing an employer's right to a safe and productive workforce with an employee's rights to avoid discrimination on the basis of their dementia risk. The review highlights these themes and emerging ethical issues in dementia.

  9. [Clinical Neuropsychology of Dementia with Lewy Bodies].

    Science.gov (United States)

    Nagahama, Yasuhiro

    2016-02-01

    Dementia with Lewy bodies (DLB) shows lesser memory impairment and more severe visuospatial disability than Alzheimer disease (AD). Although deficits in both consolidation and retrieval underlie the memory impairment, retrieval deficit is predominant in DLB. Visuospatial dysfunctions in DLB are related to the impairments in both ventral and dorsal streams of higher visual information processing, and lower visual processing in V1/V2 may also be impaired. Attention and executive functions are more widely disturbed in DLB than in AD. Imitation of finger gestures is impaired more frequently in DLB than in other mild dementia, and provides additional information for diagnosis of mild dementia, especially for DLB. Pareidolia, which lies between hallucination and visual misperception, is found frequently in DLB, but its mechanism is still under investigation.

  10. Social robots in advanced dementia

    Directory of Open Access Journals (Sweden)

    Meritxell eValentí Soler

    2015-09-01

    Full Text Available Aims: Testing the effect of the experimental robot-based therapeutic sessions for patients with dementia in: a controlled study of parallel groups of nursing home patients comparing the effects of therapy sessions utilizing a humanoid robot (NAO, an animal-shaped robot (PARO, or a trained dog (DOG, with conventional therapy (CONTROL on symptoms of dementia; and an experience for patients who attend a day care center, comparing symptom prevalence and severity before and after sessions utilizing NAO and PARO. Methods: In the nursing home, patients were randomly assigned by blocks, based on dementia severity, to one of the 3 therapeutic groups to compare: CONTROL, PARO and NAO (phase 1 and CONTROL, PARO and DOG (phase 2. In the day care center, all patients received therapy with NAO (phase 1 and PARO (phase 2. Therapy sessions were held 2 days/week for 3 months. Evaluation at baseline and follow-up was carried out by blind raters using: the Global Deterioration Scale (GDS, the Severe Mini Mental State Examination (sMMSE, the Mini Mental State Examination (MMSE, the Neuropsychiatric Inventory (NPI, the Apathy Scale for Institutionalized Patients with Dementia Nursing Home version (APADEM-NH, the Apathy Inventory (AI and the Quality of Life Scale (QUALID. Statistical analysis included descriptive statistics and non parametric tests performed by a blinded investigator. Results: In the nursing home, 101 patients (phase 1 and 110 patients (phase 2 were included. There were no significant differences at baseline. The relevant changes at follow-up were: (phase 1 patients in the robot groups showed an improvement in apathy; patients in NAO group showed a decline in cognition as measured by the MMSE scores, but not the sMMSE; the robot groups showed no significant changes between them; (phase 2 QUALID scores increased in the PARO group. In the day care center, 20 patients (phase 1 and 17 patients (phase 2 were included. The main findings were: (phase 1 imp

  11. Semantic, phonologic, and verb fluency in Huntington's disease

    Directory of Open Access Journals (Sweden)

    Mariana Jardim Azambuja

    Full Text Available Abstract Verbal fluency tasks have been identified as important indicators of executive functioning impairment in patients with frontal lobe dysfunction. Although the usual evaluation of this ability considers phonologic and semantic criteria, there is some evidence that fluency of verbs would be more sensitive in disclosing frontostriatal physiopathology since frontal regions primarily mediate retrieval of verbs. Huntington's disease usually affects these circuitries. Objective: To compare three types of verbal fluency task in the assessment of frontal-striatal dysfunction in HD subjects. Methods: We studied 26 Huntington's disease subjects, divided into two subgroups: mild (11 and moderate (15 along with 26 normal volunteers matched for age, gender and schooling, for three types of verbal fluency: phonologic fluency (F-A-S, semantic fluency and fluency of verbs. Results: Huntington's disease subjects showed a significant reduction in the number of words correctly generated in the three tasks when compared to the normal group. Both controls and Huntington's disease subjects showed a similar pattern of decreasing task performance with the greatest number of words being generated by semantic elicitation followed by verbs and lastly phonologic criteria. We did not find greater production of verbs compared with F-A-S and semantic conditions. Moreover, the fluency of verbs distinguished only the moderate group from controls. Conclusion: Our results indicated that phonologic and semantic fluency can be used to evaluate executive functioning, proving more sensitive than verb fluency. However, it is important to point out that the diverse presentations of Huntington's disease means that an extended sample is necessary for more consistent analysis of this issue.

  12. Semantic Representatives of the Concept

    Directory of Open Access Journals (Sweden)

    Elena N. Tsay

    2013-01-01

    Full Text Available In the article concept as one of the principle notions of cognitive linguistics is investigated. Considering concept as culture phenomenon, having language realization and ethnocultural peculiarities, the description of the concept “happiness” is presented. Lexical and semantic paradigm of the concept of happiness correlates with a great number of lexical and semantic variants. In the work semantic representatives of the concept of happiness, covering supreme spiritual values are revealed and semantic interpretation of their functioning in the Biblical discourse is given.

  13. System semantics of explanatory dictionaries

    Directory of Open Access Journals (Sweden)

    Volodymyr Shyrokov

    2015-11-01

    Full Text Available System semantics of explanatory dictionaries Some semantic properties of the language to be followed from the structure of lexicographical systems of big explanatory dictionaries are considered. The hyperchains and hypercycles are determined as the definite kind of automorphisms of the lexicographical system of explanatory dictionary. Some semantic consequencies following from the principles of lexicographic closure and lexicographic completeness are investigated using the hyperchains and hypercycles formalism. The connection between the hypercyle properties of the lexicographical system semantics and Goedel’s incompleteness theorem is discussed.

  14. Cognition and dementia in older patients with epilepsy

    Science.gov (United States)

    Sen, Arjune; Capelli, Valentina

    2018-01-01

    Abstract With advances in healthcare and an ageing population, the number of older adults with epilepsy is set to rise substantially across the world. In developed countries the highest incidence of epilepsy is already in people over 65 and, as life expectancy increases, individuals who developed epilepsy at a young age are also living longer. Recent findings show that older persons with epilepsy are more likely to suffer from cognitive dysfunction and that there might be an important bidirectional relationship between epilepsy and dementia. Thus some people with epilepsy may be at a higher risk of developing dementia, while individuals with some forms of dementia, particularly Alzheimer’s disease and vascular dementia, are at significantly higher risk of developing epilepsy. Consistent with this emerging view, epidemiological findings reveal that people with epilepsy and individuals with Alzheimer’s disease share common risk factors. Recent studies in Alzheimer’s disease and late-onset epilepsy also suggest common pathological links mediated by underlying vascular changes and/or tau pathology. Meanwhile electrophysiological and neuroimaging investigations in epilepsy, Alzheimer’s disease, and vascular dementia have focused interest on network level dysfunction, which might be important in mediating cognitive dysfunction across all three of these conditions. In this review we consider whether seizures promote dementia, whether dementia causes seizures, or if common underlying pathophysiological mechanisms cause both. We examine the evidence that cognitive impairment is associated with epilepsy in older people (aged over 65) and the prognosis for patients with epilepsy developing dementia, with a specific emphasis on common mechanisms that might underlie the cognitive deficits observed in epilepsy and Alzheimer’s disease. Our analyses suggest that there is considerable intersection between epilepsy, Alzheimer’s disease and cerebrovascular disease raising

  15. Causes of Death According to Death Certificates in Individuals with Dementia: A Cohort from the Swedish Dementia Registry.

    Science.gov (United States)

    Garcia-Ptacek, Sara; Kåreholt, Ingemar; Cermakova, Pavla; Rizzuto, Debora; Religa, Dorota; Eriksdotter, Maria

    2016-11-01

    The causes of death in dementia are not established, particularly in rarer dementias. The aim of this study is to calculate risk of death from specific causes for a broader spectrum of dementia diagnoses. Cohort study. Swedish Dementia Registry (SveDem), 2007-2012. Individuals with incident dementia registered in SveDem (N = 28,609); median follow-up 741 days. Observed deaths were 5,368 (19%). Information on number of deaths and causes of mortality was obtained from death certificates. Odds ratios for the presence of dementia on death certificates were calculated. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox hazards regression for cause-specific mortality, using Alzheimer's dementia (AD) as reference. Hazard ratios for death for each specific cause of death were compared with hazard ratios of death from all causes (P-values from t-tests). The most frequent underlying cause of death in this cohort was cardiovascular (37%), followed by dementia (30%). Dementia and cardiovascular causes appeared as main or contributory causes on 63% of certificates, followed by respiratory (26%). Dementia was mentioned less in vascular dementia (VaD; 57%). Compared to AD, cardiovascular mortality was higher in individuals with VaD than in those with AD (HR = 1.82, 95% CI = 1.64-2.02). Respiratory death was higher in individuals with Lewy body dementia (LBD, including Parkinson's disease dementia and dementia with Lewy bodies, HR = 2.16, 95% CI = 1.71-2.71), and the risk of respiratory death was higher than expected from the risk for all-cause mortality. Participants with frontotemporal dementia were more likely to die from external causes of death than those with AD (HR = 2.86, 95% CI = 1.53-5.32). Dementia is underreported on death certificates as main and contributory causes. Individuals with LBD had a higher risk of respiratory death than those with AD. © 2016 The Authors. The Journal of the American Geriatrics Society published by Wiley

  16. Cross border semantic interoperability for clinical research: the EHR4CR semantic resources and services

    Science.gov (United States)

    Daniel, Christel; Ouagne, David; Sadou, Eric; Forsberg, Kerstin; Gilchrist, Mark Mc; Zapletal, Eric; Paris, Nicolas; Hussain, Sajjad; Jaulent, Marie-Christine; MD, Dipka Kalra

    2016-01-01

    With the development of platforms enabling the use of routinely collected clinical data in the context of international clinical research, scalable solutions for cross border semantic interoperability need to be developed. Within the context of the IMI EHR4CR project, we first defined the requirements and evaluation criteria of the EHR4CR semantic interoperability platform and then developed the semantic resources and supportive services and tooling to assist hospital sites in standardizing their data for allowing the execution of the project use cases. The experience gained from the evaluation of the EHR4CR platform accessing to semantically equivalent data elements across 11 European participating EHR systems from 5 countries demonstrated how far the mediation model and mapping efforts met the expected requirements of the project. Developers of semantic interoperability platforms are beginning to address a core set of requirements in order to reach the goal of developing cross border semantic integration of data. PMID:27570649

  17. Semantic Indexing of Medical Learning Objects: Medical Students' Usage of a Semantic Network.

    Science.gov (United States)

    Tix, Nadine; Gießler, Paul; Ohnesorge-Radtke, Ursula; Spreckelsen, Cord

    2015-11-11

    The Semantically Annotated Media (SAM) project aims to provide a flexible platform for searching, browsing, and indexing medical learning objects (MLOs) based on a semantic network derived from established classification systems. Primarily, SAM supports the Aachen emedia skills lab, but SAM is ready for indexing distributed content and the Simple Knowledge Organizing System standard provides a means for easily upgrading or even exchanging SAM's semantic network. There is a lack of research addressing the usability of MLO indexes or search portals like SAM and the user behavior with such platforms. The purpose of this study was to assess the usability of SAM by investigating characteristic user behavior of medical students accessing MLOs via SAM. In this study, we chose a mixed-methods approach. Lean usability testing was combined with usability inspection by having the participants complete four typical usage scenarios before filling out a questionnaire. The questionnaire was based on the IsoMetrics usability inventory. Direct user interaction with SAM (mouse clicks and pages accessed) was logged. The study analyzed the typical usage patterns and habits of students using a semantic network for accessing MLOs. Four scenarios capturing characteristics of typical tasks to be solved by using SAM yielded high ratings of usability items and showed good results concerning the consistency of indexing by different users. Long-tail phenomena emerge as they are typical for a collaborative Web 2.0 platform. Suitable but nonetheless rarely used keywords were assigned to MLOs by some users. It is possible to develop a Web-based tool with high usability and acceptance for indexing and retrieval of MLOs. SAM can be applied to indexing multicentered repositories of MLOs collaboratively.

  18. The Semantic Web Revisited

    OpenAIRE

    Shadbolt, Nigel; Berners-Lee, Tim; Hall, Wendy

    2006-01-01

    The original Scientific American article on the Semantic Web appeared in 2001. It described the evolution of a Web that consisted largely of documents for humans to read to one that included data and information for computers to manipulate. The Semantic Web is a Web of actionable information--information derived from data through a semantic theory for interpreting the symbols.This simple idea, however, remains largely unrealized. Shopbots and auction bots abound on the Web, but these are esse...

  19. A Quest for Meaning: Hospice Social Workers and Patients with End-Stage Dementia

    Science.gov (United States)

    Sanders, Sara; Swails, Peggy

    2011-01-01

    Research shows that few social workers are interested in working with cognitively impaired older adults, such as those with Alzheimer's disease or a related dementia. As the number of individuals with dementia grows, the demand for social workers to provide services to patients with dementia will increase. Although much attention has been given to…

  20. Semantic Search of Web Services

    Science.gov (United States)

    Hao, Ke

    2013-01-01

    This dissertation addresses semantic search of Web services using natural language processing. We first survey various existing approaches, focusing on the fact that the expensive costs of current semantic annotation frameworks result in limited use of semantic search for large scale applications. We then propose a vector space model based service…

  1. [Study on the change of semantic perspective of schistosomiasis control in China].

    Science.gov (United States)

    Zhou, Li-ying; Liu, Si-yuan; Li, Yu-ye; Deng, Yao; Yang, Kun

    2015-12-01

    To analyze the evolution process, discourse and semantic meaning of schistosomiasis prevention and control, so as to provide suggestions for control work. The official documents and mainstream media reports of schistosomiasis prevention and control were selected at different periods as discourse samples, and the deep social reasons behind the strategy change and the semantic meaning of the utterance were analyzed at different periods. The discourse of schistosomiasis prevention and control experienced the evolution of the political discourse, pluralistic discourse and public discourse, and the semantic connotations showed the authority conflict semantic features, and then transferred to semantic cooperation. The prevention and control of schistosomiasis have different semantic meanings at different periods, and the prevention and control work should correspond to a social practice, seek truth from facts, correctly understand the actual situation, and then establish the effective control policy.

  2. Semantic Barbs and Biorthogonality

    OpenAIRE

    Rathke, J.; Sassone, V.; Sobocinski, P.

    2007-01-01

    We use the framework of biorthogonality to introduce a novel semantic definition of the concept of barb (basic observable) for process calculi. We develop a uniform basic theory of barbs and demonstrate its robustness by showing that it gives rise to the correct observables in specific process calculi which model synchronous, asynchronous and broadcast communication regimes.

  3. Semantic congruence enhances memory of episodic associations: role of theta oscillations.

    Science.gov (United States)

    Atienza, Mercedes; Crespo-Garcia, Maite; Cantero, Jose L

    2011-01-01

    Growing evidence suggests that theta oscillations play a crucial role in episodic encoding. The present study evaluates whether changes in electroencephalographic theta source dynamics mediate the positive influence of semantic congruence on incidental associative learning. Here we show that memory for episodic associations (face-location) is more accurate when studied under semantically congruent contexts. However, only participants showing RT priming effect in a conceptual priming test (priming group) also gave faster responses when recollecting source information of semantically congruent faces as compared with semantically incongruent faces. This improved episodic retrieval was positively correlated with increases in theta power during the study phase mainly in the bilateral parahippocampal gyrus, left superior temporal gyrus, and left lateral posterior parietal lobe. Reconstructed signals from the estimated sources showed higher theta power for congruent than incongruent faces and also for the priming than the nonpriming group. These results are in agreement with the attention to memory model. Besides directing top-down attention to goal-relevant semantic information during encoding, the dorsal parietal lobe may also be involved in redirecting attention to bottom-up-driven memories thanks to connections between the medial-temporal and the left ventral parietal lobe. The latter function can either facilitate or interfere with encoding of face-location associations depending on whether they are preceded by semantically congruent or incongruent contexts, respectively, because only in the former condition retrieved representations related to the cue and the face are both coherent with the person identity and are both associated with the same location.

  4. Influence of dementia on pain

    NARCIS (Netherlands)

    Scherder, E

    2006-01-01

    In the next decades the number of older persons with dementia and with a painful condition will increase. This is an important conclusion since at this moment older persons with dementia and a painful condition receive less analgesic medication than older persons without dementia. One explanation

  5. Diagnostic criteria for vascular dementia

    NARCIS (Netherlands)

    Scheltens, P.; Hijdra, A. H.

    1998-01-01

    The term vascular dementia implies the presence of a clinical syndrome (dementia) caused by, or at least assumed to be caused by, a specific disorder (cerebrovascular disease). In this review, the various sets of criteria used to define vascular dementia are outlined. The various sets of criteria

  6. False recognition correlates with amyloid-beta (1-42) but not with total tau in cerebrospinal fluid of patients with dementia and mild cognitive impairment.

    Science.gov (United States)

    Hildebrandt, Helmut; Haldenwanger, Andreas; Eling, Paul

    2009-01-01

    Severe memory impairment forms the core symptom of Alzheimer's disease (AD), which is present early in the disease course. Recent studies show that AD patients not only suffer from forgetfulness, but also differ in their response bias, when having to decide whether information has been perceived recently, or whether it is only familiar or semantically related to perceived information. Changes in total tau-protein and amyloid-beta (Abeta) (1-42) concentration in cerebrospinal fluid are also features of AD, and they predict conversion from mild cognitive impairment to dementia. In this study we correlated recognition scores with total tau and Abeta (1-42) concentrations in patients with suggested dementia. We studied 40 patients and 21 healthy controls, using an incidental recognition memory task and a neuropsychological test battery. False recognition scores correlated with delayed recall and with Abeta(1-42), and Abeta (1-42) tended to correlate with delayed recall. Total tau, however, did not correlate with memory scores or with neuropsychological performance in general. We suggest that Abeta (1-42) may indicate a reduction in the specificity of the neuronal response in the limbic cortex, due to agglomeration of plaques. This process might be more specific for AD than the increase of tau, and therefore it is stronger correlated with recognition errors.

  7. Activities in dementia care: A comparative assessment of activity types.

    Science.gov (United States)

    Lokon, Elizabeth; Sauer, Philip E; Li, Yue

    2016-12-05

    This exploratory study compares the impact of five activity types on the well-being of institutionalized people with dementia: the intergenerational art program Opening Minds through Art, art and music therapies, creative activities, non-creative activities, and no activities at all. We validated the Scripps Modified Greater Cincinnati Chapter Well-Being Observational Tool, and used that instrument to systematically observe N = 67 people with dementia as they participated in different activity types. People with dementia showed the highest well-being scores during Opening Minds through Art compared to all other activities. No significant well-being differences were found between creative activities led by licensed art/music therapist versus regular activity staff. Furthermore, no significant well-being differences were found between creative and non-creative activities that were both led by regular activity staff. Overall, people with dementia benefit from participating in activities, regardless of the type (creative or non-creative), or who conducts them (licensed therapists or activity staff). However, in order for people with dementia to reach significantly high levels of overall well-being, we recommend that activities are specifically designed for people with dementia and incorporate a 1:1 ratio between people with dementia and well-trained volunteers/staff members. © The Author(s) 2016.

  8. The Rest-Activity Rhythm and Physical Activity in Early-Onset Dementia

    NARCIS (Netherlands)

    Hooghiemstra, A.M.; Eggermont, L.H.P.; Scheltens, P.; van der Flier, W.M.; Scherder, E.J.A.

    2015-01-01

    Background: A substantial part of elderly persons with dementia show rest-activity rhythm disturbances. The rest-activity rhythm is important to study in people with early-onset dementia (EOD) for rest-activity rhythm disturbances are predictive of institutionalization, and caregivers of young

  9. Dementia: sociological and philosophical constructions.

    Science.gov (United States)

    Davis, Daniel H J

    2004-01-01

    This analysis presents a challenge to the biomedical view of dementia as a disease. This view is critiqued from two perspectives: those of sociology and philosophy. Because these domains inform the creation of the medical discourse, their analysis provides an important refinement to the apprehension of the phenomenon of dementia. From the work of Foucault, and in particular his analysis of the historical origins of modern medicine, the sociological construction of dementia is considered. Following this, the philosophical question of Being is discussed, considering particularly the positions of Heidegger and Merleau-Ponty. Lastly aspects of dementia nursing that are damaging to those relatives forced to take on the role of primary carer are isolated, in the context of Kitwood's view that it is possible to maintain personhood at the extremes of this condition. It is suggested that this critique of sociological and philosophical foundations of dementia might offer a way of approaching the dismantling of the self and revise current conceptions of dementia care for the better.

  10. Living better with dementia: strengths-based social work practice and dementia care.

    Science.gov (United States)

    McGovern, Justine

    2015-01-01

    This article first argues that quality of life is possible despite the onset of dementia in late life. It also demonstrates how core concepts of social work practice, such as family systems theory, the strengths perspective, and use of self, can be applied to practice with dementia-affected persons. In addition, it provides practical suggestions for supporting care partners in nurturing "we-ness", focusing on what remains rather than was is lost, and remaining authentic. When strengths-based social work practice is integrated into dementia care protocols, wellbeing can increase. As a result, the more than 40 million persons worldwide who are affected by dementia do not have to resign themselves to the despair, devastation and inevitable demise of quality of life that dominate perception of the illness.

  11. Exploring and linking biomedical resources through multidimensional semantic spaces.

    Science.gov (United States)

    Berlanga, Rafael; Jiménez-Ruiz, Ernesto; Nebot, Victoria

    2012-01-25

    The semantic integration of biomedical resources is still a challenging issue which is required for effective information processing and data analysis. The availability of comprehensive knowledge resources such as biomedical ontologies and integrated thesauri greatly facilitates this integration effort by means of semantic annotation, which allows disparate data formats and contents to be expressed under a common semantic space. In this paper, we propose a multidimensional representation for such a semantic space, where dimensions regard the different perspectives in biomedical research (e.g., population, disease, anatomy and protein/genes). This paper presents a novel method for building multidimensional semantic spaces from semantically annotated biomedical data collections. This method consists of two main processes: knowledge and data normalization. The former one arranges the concepts provided by a reference knowledge resource (e.g., biomedical ontologies and thesauri) into a set of hierarchical dimensions for analysis purposes. The latter one reduces the annotation set associated to each collection item into a set of points of the multidimensional space. Additionally, we have developed a visual tool, called 3D-Browser, which implements OLAP-like operators over the generated multidimensional space. The method and the tool have been tested and evaluated in the context of the Health-e-Child (HeC) project. Automatic semantic annotation was applied to tag three collections of abstracts taken from PubMed, one for each target disease of the project, the Uniprot database, and the HeC patient record database. We adopted the UMLS Meta-thesaurus 2010AA as the reference knowledge resource. Current knowledge resources and semantic-aware technology make possible the integration of biomedical resources. Such an integration is performed through semantic annotation of the intended biomedical data resources. This paper shows how these annotations can be exploited for

  12. The accuracy of family physicians' dementia diagnoses at different stages of dementia: a systematic review

    NARCIS (Netherlands)

    van den Dungen, Pim; van Marwijk, Harm W. M.; van der Horst, Henriëtte E.; Moll van Charante, Eric P.; Macneil Vroomen, Janet; van de Ven, Peter M.; van Hout, Hein P. J.

    2012-01-01

    Objective: Optimising care for dementia patients and their informal carers is imperative in light of the impending dementia epidemic. An important aspect of care is accurate recognition and diagnosis of dementia. The aim of this review was to estimate family physicians' diagnostic accuracy at the

  13. The accuracy of family physicians' dementia diagnoses at different stages of dementia: a systematic review

    NARCIS (Netherlands)

    van den Dungen, P.; van Marwijk, H.W.J.; van der Horst, H.E.; van Charante, E.P.M.; Vroomen, J.M.; van de Ven, P.M.; van Hout, H.P.J.

    2012-01-01

    Objective Optimising care for dementia patients and their informal carers is imperative in light of the impending dementia epidemic. An important aspect of care is accurate recognition and diagnosis of dementia. The aim of this review was to estimate family physicians' diagnostic accuracy at the

  14. Ontology alignment architecture for semantic sensor Web integration.

    Science.gov (United States)

    Fernandez, Susel; Marsa-Maestre, Ivan; Velasco, Juan R; Alarcos, Bernardo

    2013-09-18

    Sensor networks are a concept that has become very popular in data acquisition and processing for multiple applications in different fields such as industrial, medicine, home automation, environmental detection, etc. Today, with the proliferation of small communication devices with sensors that collect environmental data, semantic Web technologies are becoming closely related with sensor networks. The linking of elements from Semantic Web technologies with sensor networks has been called Semantic Sensor Web and has among its main features the use of ontologies. One of the key challenges of using ontologies in sensor networks is to provide mechanisms to integrate and exchange knowledge from heterogeneous sources (that is, dealing with semantic heterogeneity). Ontology alignment is the process of bringing ontologies into mutual agreement by the automatic discovery of mappings between related concepts. This paper presents a system for ontology alignment in the Semantic Sensor Web which uses fuzzy logic techniques to combine similarity measures between entities of different ontologies. The proposed approach focuses on two key elements: the terminological similarity, which takes into account the linguistic and semantic information of the context of the entity's names, and the structural similarity, based on both the internal and relational structure of the concepts. This work has been validated using sensor network ontologies and the Ontology Alignment Evaluation Initiative (OAEI) tests. The results show that the proposed techniques outperform previous approaches in terms of precision and recall.

  15. Ontology Alignment Architecture for Semantic Sensor Web Integration

    Directory of Open Access Journals (Sweden)

    Bernardo Alarcos

    2013-09-01

    Full Text Available Sensor networks are a concept that has become very popular in data acquisition and processing for multiple applications in different fields such as industrial, medicine, home automation, environmental detection, etc. Today, with the proliferation of small communication devices with sensors that collect environmental data, semantic Web technologies are becoming closely related with sensor networks. The linking of elements from Semantic Web technologies with sensor networks has been called Semantic Sensor Web and has among its main features the use of ontologies. One of the key challenges of using ontologies in sensor networks is to provide mechanisms to integrate and exchange knowledge from heterogeneous sources (that is, dealing with semantic heterogeneity. Ontology alignment is the process of bringing ontologies into mutual agreement by the automatic discovery of mappings between related concepts. This paper presents a system for ontology alignment in the Semantic Sensor Web which uses fuzzy logic techniques to combine similarity measures between entities of different ontologies. The proposed approach focuses on two key elements: the terminological similarity, which takes into account the linguistic and semantic information of the context of the entity’s names, and the structural similarity, based on both the internal and relational structure of the concepts. This work has been validated using sensor network ontologies and the Ontology Alignment Evaluation Initiative (OAEI tests. The results show that the proposed techniques outperform previous approaches in terms of precision and recall.

  16. Neural correlates of concreteness in semantic categorization.

    Science.gov (United States)

    Pexman, Penny M; Hargreaves, Ian S; Edwards, Jodi D; Henry, Luke C; Goodyear, Bradley G

    2007-08-01

    In some contexts, concrete words (CARROT) are recognized and remembered more readily than abstract words (TRUTH). This concreteness effect has historically been explained by two theories of semantic representation: dual-coding [Paivio, A. Dual coding theory: Retrospect and current status. Canadian Journal of Psychology, 45, 255-287, 1991] and context-availability [Schwanenflugel, P. J. Why are abstract concepts hard to understand? In P. J. Schwanenflugel (Ed.), The psychology of word meanings (pp. 223-250). Hillsdale, NJ: Erlbaum, 1991]. Past efforts to adjudicate between these theories using functional magnetic resonance imaging have produced mixed results. Using event-related functional magnetic resonance imaging, we reexamined this issue with a semantic categorization task that allowed for uniform semantic judgments of concrete and abstract words. The participants were 20 healthy adults. Functional analyses contrasted activation associated with concrete and abstract meanings of ambiguous and unambiguous words. Results showed that for both ambiguous and unambiguous words, abstract meanings were associated with more widespread cortical activation than concrete meanings in numerous regions associated with semantic processing, including temporal, parietal, and frontal cortices. These results are inconsistent with both dual-coding and context-availability theories, as these theories propose that the representations of abstract concepts are relatively impoverished. Our results suggest, instead, that semantic retrieval of abstract concepts involves a network of association areas. We argue that this finding is compatible with a theory of semantic representation such as Barsalou's [Barsalou, L. W. Perceptual symbol systems. Behavioral & Brain Sciences, 22, 577-660, 1999] perceptual symbol systems, whereby concrete and abstract concepts are represented by similar mechanisms but with differences in focal content.

  17. Reminiscence in dementia: a concept analysis.

    Science.gov (United States)

    Dempsey, Laura; Murphy, Kathy; Cooney, Adeline; Casey, Dympna; O'Shea, Eamon; Devane, Declan; Jordan, Fionnuala; Hunter, Andrew

    2014-03-01

    This paper is a report of an analysis of the concept of reminiscence in dementia and highlights its uses as a therapeutic intervention used on individuals with dementia. No single definition of reminiscence exists in healthcare literature; however, definitions offered have similar components. The term life review is commonly used when discussing reminiscence; however, both terms are quite different in their goals, theory base and content. This concept analysis identified reminiscence as a process which occurs in stages, involving the recalling of early life events and interaction between individuals. The antecedents of reminiscence are age, life transitions, attention span, ability to recall, ability to vocalise and stressful situations. Reminiscence can lead to positive mental health, enhanced self esteem and improved communication skills. It also facilitates preparation for death, increases interaction between people, prepares for the future and evaluates a past life. Reminiscence therapy is used extensively in dementia care and evidence shows when used effectively it helps individuals retain a sense of self worth, identity and individuality.

  18. A longitudinal study of CMRGlu in dementia of Alzheimer type

    Energy Technology Data Exchange (ETDEWEB)

    Kuwabara, Yasuo; Ichiya, Yuichi; Ichimiya, Atsushi; Sasaki, Masayuki; Akashi, Yuko; Yoshida, Tsuyoshi; Fukumura, Toshimitsu; Masuda, Kouji [Kyushu Univ., Fukuoka (Japan). Faculty of Medicine

    1994-10-01

    We studied the serial changes of CMRGlu in 6 patients with dementia of Alzheimer type. All patients demonstrated moderately severe dementia at the initial PET scan. Serial PET scans were performed at an interval of 12 to 24 months. Five of the 6 patients showed a deterioration of clinical symptoms at the second scan. The global CMRGlu serially decreased in all patients. An asymmetry of CMRGlu in both the frontal and parietal regions was observed at the initial PET scan, while the direction of asymmetry was preserved at the second PET scan. The ratios (frontal/parietal and parietal/striatum) of CMRGlu showed no interval change. Therefore, CMRGlu was considered to decrease progressively throughout the entire brain in patients with moderately severe dementia of Alzheimer type. (author).

  19. A longitudinal study of CMRGlu in dementia of Alzheimer type

    International Nuclear Information System (INIS)

    Kuwabara, Yasuo; Ichiya, Yuichi; Ichimiya, Atsushi; Sasaki, Masayuki; Akashi, Yuko; Yoshida, Tsuyoshi; Fukumura, Toshimitsu; Masuda, Kouji

    1994-01-01

    We studied the serial changes of CMRGlu in 6 patients with dementia of Alzheimer type. All patients demonstrated moderately severe dementia at the initial PET scan. Serial PET scans were performed at an interval of 12 to 24 months. Five of the 6 patients showed a deterioration of clinical symptoms at the second scan. The global CMRGlu serially decreased in all patients. An asymmetry of CMRGlu in both the frontal and parietal regions was observed at the initial PET scan, while the direction of asymmetry was preserved at the second PET scan. The ratios (frontal/parietal and parietal/striatum) of CMRGlu showed no interval change. Therefore, CMRGlu was considered to decrease progressively throughout the entire brain in patients with moderately severe dementia of Alzheimer type. (author)

  20. Smart Homes Design for People with Dementia

    OpenAIRE

    Amiribesheli, Mohsen; Bouchachia, Abdelhamid

    2015-01-01

    In this paper, we present a user-centred approach for designing and developing smart homes for people with dementia. In contrast to most of the existing literature related to dementia, the present approach aims at tailoring the system to the specific needs of dementia using a scenario-based methodology. Scenarios are based on typical dementia symptoms which are collected from research literatures and validated by dementia caregivers. They portray the common behaviour of people with dementia. ...

  1. Prognosis of dementia

    NARCIS (Netherlands)

    van de Vorst, IE

    2016-01-01

    Background: In this thesis, we focused on the prognosis of patients with dementia who visited a hospital (inpatient or day clinic care) in the Netherlands. So far, absolute mortality risks for dementia were lacking in the Netherlands, whereas these risks have been available for years for cancer or

  2. LAIR: A Language for Automated Semantics-Aware Text Sanitization based on Frame Semantics

    DEFF Research Database (Denmark)

    Hedegaard, Steffen; Houen, Søren; Simonsen, Jakob Grue

    2009-01-01

    We present \\lair{}: A domain-specific language that enables users to specify actions to be taken upon meeting specific semantic frames in a text, in particular to rephrase and redact the textual content. While \\lair{} presupposes superficial knowledge of frames and frame semantics, it requires on...... with automated redaction of web pages for subjectively undesirable content; initial experiments suggest that using a small language based on semantic recognition of undesirable terms can be highly useful as a supplement to traditional methods of text sanitization.......We present \\lair{}: A domain-specific language that enables users to specify actions to be taken upon meeting specific semantic frames in a text, in particular to rephrase and redact the textual content. While \\lair{} presupposes superficial knowledge of frames and frame semantics, it requires only...... limited prior programming experience. It neither contain scripting or I/O primitives, nor does it contain general loop constructions and is not Turing-complete. We have implemented a \\lair{} compiler and integrated it in a pipeline for automated redaction of web pages. We detail our experience...

  3. Retrograde amnesia for semantic information in Alzheimer's disease

    OpenAIRE

    Meeter, M.; Kollen, A.; Scheltens, P.

    2005-01-01

    Patients with mild to moderate Alzheimer's disease and normal controls were tested on a retrograde amnesia test with semantic content (Neologism and Vocabulary Test, or NVT), consisting of neologisms to be defined. Patients showed a decrement as compared to normal controls, pointing to retrograde amnesia within semantic memory. No evidence for a gradient within this amnesia was found, although one was present on an autobiographic test of retrograde amnesia that had a wider time scale. Several...

  4. The Swedish BioFINDER 2 Study

    Science.gov (United States)

    2018-04-16

    Dementia; Alzheimer Disease; Parkinson Disease; Lewy Body Disease; Parkinson-Dementia Syndrome; Frontotemporal Degeneration; Semantic Dementia; Progressive Nonfluent Aphasia; Progressive Supranuclear Palsy; Corticobasal Degeneration; Multiple System Atrophy; Mild Cognitive Impairment

  5. Clinical-physiologic correlates of Alzheimer's disease and frontal lobe dementia

    International Nuclear Information System (INIS)

    Jagust, W.J.; Reed, B.R.; Seab, J.P.; Kramer, J.H.; Budinger, T.F.

    1989-01-01

    Thirty patients with degenerative dementia underwent clinical evaluation, neuropsychological testing, and single photon emission computed tomography (SPECT) with the blood flow tracer [ 123 I]-N-isopropyl-p-iodoamphetamine. Five of these patients were clinically and psychologically different from the others, demonstrating predominant behavioral disturbances with relative preservation of memory function. These five patients, who were felt to have a frontal lobe dementia (FLD), showed SPECT perfusion patterns which differed from the remaining 25 patients, who were diagnosed as having Alzheimer's disease (AD), and from 16 healthy control subjects. The FLD patients showed diminished perfusion in orbitofrontal, dorsolateral frontal, and temporal cortex relative to controls, while the AD patients showed lower perfusion in temporal and parietal cortex than controls. The FLD patients also showed hypoperfusion in both frontal cortical regions relative to AD patients. The pattern of performance on neuropsychological testing paralleled these differences in regional perfusion. These results suggest that clinical evaluation and physiological imaging may enable the differentiation of groups of degenerative dementia patients during life

  6. Aromatherapy for dementia.

    Science.gov (United States)

    Forrester, Lene Thorgrimsen; Maayan, Nicola; Orrell, Martin; Spector, Aimee E; Buchan, Louise D; Soares-Weiser, Karla

    2014-02-25

    Complementary therapy has received great interest within the field of dementia treatment and the use of aromatherapy and essential oils is increasing. In a growing population where the majority of patients are treated by US Food and Drug Administration (FDA)-approved drugs, the efficacy of treatment is short term and accompanied by negative side effects. Utilisation of complimentary therapies in dementia care settings presents as one of few options that are attractive to practitioners and families as patients often have reduced insight and ability to verbally communicate adverse reactions. Amongst the most distressing features of dementia are the behavioural and psychological symptoms. Addressing this facet has received particular interest in aromatherapy trials, with a shift in focus from reducing cognitive dysfunction to the reduction of behavioural and psychological symptoms in dementia. To assess the efficacy of aromatherapy as an intervention for people with dementia. ALOIS, the Cochrane Dementia and Cognitive Improvement Group Specialized Register, was searched on 26 November 2012 and 20 January 2013 using the terms: aromatherapy, lemon, lavender, rose, aroma, alternative therapies, complementary therapies, essential oils. All relevant randomised controlled trials were considered. A minimum length of a trial and requirements for follow-up were not included, and participants in included studies had a diagnosis of dementia of any type and severity. The review considered all trials using fragrance from plants defined as aromatherapy as an intervention with people with dementia and all relevant outcomes were considered. Titles and abstracts extracted by the searches were screened for their eligibility for potential inclusion in the review. For Burns 2011, continuous outcomes were estimated as the mean difference between groups and its 95% confidence interval using a fixed-effect model. For Ballard 2002, analysis of co-variance was used for all outcomes, with the

  7. The 10/66 Dementia Research Group's fully operationalised DSM-IV dementia computerized diagnostic algorithm, compared with the 10/66 dementia algorithm and a clinician diagnosis: a population validation study

    Directory of Open Access Journals (Sweden)

    Krishnamoorthy ES

    2008-06-01

    Full Text Available Abstract Background The criterion for dementia implicit in DSM-IV is widely used in research but not fully operationalised. The 10/66 Dementia Research Group sought to do this using assessments from their one phase dementia diagnostic research interview, and to validate the resulting algorithm in a population-based study in Cuba. Methods The criterion was operationalised as a computerised algorithm, applying clinical principles, based upon the 10/66 cognitive tests, clinical interview and informant reports; the Community Screening Instrument for Dementia, the CERAD 10 word list learning and animal naming tests, the Geriatric Mental State, and the History and Aetiology Schedule – Dementia Diagnosis and Subtype. This was validated in Cuba against a local clinician DSM-IV diagnosis and the 10/66 dementia diagnosis (originally calibrated probabilistically against clinician DSM-IV diagnoses in the 10/66 pilot study. Results The DSM-IV sub-criteria were plausibly distributed among clinically diagnosed dementia cases and controls. The clinician diagnoses agreed better with 10/66 dementia diagnosis than with the more conservative computerized DSM-IV algorithm. The DSM-IV algorithm was particularly likely to miss less severe dementia cases. Those with a 10/66 dementia diagnosis who did not meet the DSM-IV criterion were less cognitively and functionally impaired compared with the DSMIV confirmed cases, but still grossly impaired compared with those free of dementia. Conclusion The DSM-IV criterion, strictly applied, defines a narrow category of unambiguous dementia characterized by marked impairment. It may be specific but incompletely sensitive to clinically relevant cases. The 10/66 dementia diagnosis defines a broader category that may be more sensitive, identifying genuine cases beyond those defined by our DSM-IV algorithm, with relevance to the estimation of the population burden of this disorder.

  8. A generalized notion of semantic independence

    DEFF Research Database (Denmark)

    Fränzle, Martin; Stengel, Bernhard von; Wittmüss, Arne

    1995-01-01

    For programs represented semantically as relations, a concept of semantic independence is defined that is more general than previously stated notions. It allows for shared input variables and irrelevant interference due to nondeterminism.......For programs represented semantically as relations, a concept of semantic independence is defined that is more general than previously stated notions. It allows for shared input variables and irrelevant interference due to nondeterminism....

  9. The Use of Profanity During Letter Fluency Tasks in Frontotemporal Dementia and Alzheimer's Disease

    Science.gov (United States)

    Ringman, John M.; Kwon, Eunice; Flores, Deborah L.; Rotko, Carol; Mendez, Mario F.; Lu, Po

    2012-01-01

    Objective To assess whether the production of profanity during letter fluency testing distinguishes frontotemporal dementia (FTD) and Alzheimer's disease (AD) patients. Background Alterations in language and social behavior typify FTD spectrum disorders. Nonetheless, in can be difficult to distinguish pathologically-defined frontotemporal lobar degeneration (FTLD) from AD clinically. Assessing verbal fluency by having patients generate as many words as they can beginning with specific letters in a given period of time can yield diverse information of diagnostic utility. Method Words produced during FAS letter fluency testing were reviewed and instances of the use of "f*ck", "*ss", and "sh*t" and other words felt to be inappropriate were sought. The frequency of these words was compared between clinically diagnosed FTD and AD patients using chi-square tests. Results We found that 6/32 (18.8%) patients with FTD generated the word "f*ck" during the "F" trial as opposed to none of 38 patients with AD (p = 0.007). Patients who said "f*ck" had diagnoses of either behavioral variant FTD (3/15), progressive non-fluent aphasia (2/8), or semantic dementia (1/3). Conclusions Though the specific neuropathology in these cases is uncertain, generation of "f*ck" during letter fluency testing appears to have utility in differentiating FTD from AD. PMID:20829665

  10. Anticholinergic drug use is associated with episodic memory decline in older adults without dementia.

    Science.gov (United States)

    Papenberg, Goran; Bäckman, Lars; Fratiglioni, Laura; Laukka, Erika J; Fastbom, Johan; Johnell, Kristina

    2017-07-01

    Anticholinergic drug use is common in older adults and has been related to increased dementia risk. This suggests that users of these drugs may experience accelerated cognitive decline. So far, however, longitudinal data on this topic are absent and the available evidence is inconclusive with respect to effects on specific cognitive domains due to suboptimal control of confounding variables. We investigated whether anticholinergic medication use is associated with cognitive decline over 6 years in a population-based study of older adults (aged 60-90; n = 1473) without dementia. We found that users (n = 29) declined more on episodic memory over 6 years compared to nonusers (n = 1418). These results were independent of age, sex, education, overall drug intake, physical activity, depression, cardiovascular risk burden, and cardiovascular disease. By contrast, anticholinergic drug use was unrelated to performance in processing speed, semantic memory, short-term memory, verbal fluency, and global cognition (the Mini-Mental-State Examination). Our results suggest that effects of anticholinergics may be particularly detrimental to episodic memory in older adults, which supports the assertion that the cholinergic system plays an important role in episodic memory formation. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Professional Caregivers' Perceptions on how Persons with Mild Dementia Might Experience the Usage of a Digital Photo Diary.

    Science.gov (United States)

    Harrefors, Christina; Sävenstedt, Stefan; Lundquist, Anders; Lundquist, Bengt; Axelsson, Karin

    2012-01-01

    Cognitive impairments influence the possibility of persons with dementia to remember daily events and maintain a sense of self. In order to address these problems a digital photo diary was developed to capture information about events in daily life. The device consisted of a wearable digital camera, smart phone with Global Positioning System (GPS) and a home memory station with computer for uploading the photographs and touch screen. The aim of this study was to describe professional caregiver's perceptions on how persons with mild dementia might experience the usage of this digital photo diary from both a situation when wearing the camera and a situation when viewing the uploaded photos, through a questionnaire with 408 respondents. In order to catch the professional caregivers' perceptions a questionnaire with the semantic differential technique was used and the main question was "How do you think Hilda (the fictive person in the questionnaire) feels when she is using the digital photo diary?". The factor analysis revealed three factors; Sense of autonomy, Sense of self-esteem and Sense of trust. An interesting conclusion that can be drawn is that professional caregivers had an overall positive view of the usage of digital photo diary as supporting autonomy for persons with mild dementia. The meaningfulness of each situation when wearing the camera and viewing the uploaded pictures to be used in two different situations and a part of an integrated assistive device has to be considered separately. Individual needs and desires of the person who is living with dementia and the context of each individual has to be reflected on and taken into account before implementing assistive digital devices as a tool in care.

  12. [Memantine as add-on medication to acetylcholinesterase inhibitor therapy for Alzheimer dementia].

    Science.gov (United States)

    Haussmann, R; Donix, M

    2017-01-01

    Currently available data indicate superior therapeutic effects of combination treatment for Alzheimer dementia with memantine and acetylcholine esterase inhibitors in certain clinical contexts. Out of five randomized, placebo-controlled, double-blind trials two showed superior therapeutic effects in comparison to monotherapy with acetylcholinesterase inhibitors regarding various domains. Recently published meta-analyses and cost-benefit analyses also showed positive results. Recently published German guidelines for dementia treatment also take these new data into account and recommend combination treatment in patients with severe dementia on stable donepezil medication. This article gives an overview of current evidence for combination therapy.

  13. Functional connectivity in cortical regions in dementia with Lewy bodies and Alzheimer's disease.

    Science.gov (United States)

    Kenny, Eva R; Blamire, Andrew M; Firbank, Michael J; O'Brien, John T

    2012-02-01

    Using resting-state functional magnetic resonance imaging, spontaneous low-frequency fluctuations in the blood oxygenation level-dependent signal were measured to investigate connectivity between key brain regions hypothesized to be differentially affected in dementia with Lewy bodies compared with Alzheimer's disease and healthy controls. These included connections of the hippocampus, because of its role in learning, and parietal and occipital areas involved in memory, attention and visual processing. Connectivity was investigated in 47 subjects aged 60 years and over: 15 subjects with dementia with Lewy bodies, 16 subjects with Alzheimer's disease and 16 control subjects. Subjects were scanned using a 3 Tesla magnetic resonance imaging system. The mean blood oxygenation level-dependent signal time series was extracted from seed regions in the hippocampus, posterior cingulate cortex, precuneus and primary visual cortex and correlated with all other brain voxels to determine functional connectivity. Both subjects with dementia with Lewy bodies and Alzheimer's disease showed greater connectivity than control subjects. Compared with controls, the dementia with Lewy bodies group had greater connectivity between the right posterior cingulate cortex and other brain areas. In dementia with Lewy bodies, there were no significant differences in hippocampal connectivity compared with controls, but in Alzheimer's disease left hippocampal connectivity was greater compared with controls. There were no significant differences between groups for precuneus or primary visual cortex connectivity. No seed regions showed significantly less connectivity in subjects with dementia with Lewy bodies or Alzheimer's disease compared with controls. We found greater connectivity with the posterior cingulate in dementia with Lewy bodies and with the hippocampus in Alzheimer's disease. Consistent with the known relative preservation of memory in dementia with Lewy bodies compared with Alzheimer

  14. Comparing Refinements for Failure and Bisimulation Semantics

    NARCIS (Netherlands)

    Eshuis, H.; Fokkinga, M.M.

    2002-01-01

    Refinement in bisimulation semantics is defined differently from refinement in failure semantics: in bisimulation semantics refinement is based on simulations between labelled transition systems, whereas in failure semantics refinement is based on inclusions between failure systems. There exist

  15. Varieties of semantic cognition revealed through simultaneous decomposition of intrinsic brain connectivity and behaviour.

    Science.gov (United States)

    Vatansever, Deniz; Bzdok, Danilo; Wang, Hao-Ting; Mollo, Giovanna; Sormaz, Mladen; Murphy, Charlotte; Karapanagiotidis, Theodoros; Smallwood, Jonathan; Jefferies, Elizabeth

    2017-09-01

    Contemporary theories assume that semantic cognition emerges from a neural architecture in which different component processes are combined to produce aspects of conceptual thought and behaviour. In addition to the state-level, momentary variation in brain connectivity, individuals may also differ in their propensity to generate particular configurations of such components, and these trait-level differences may relate to individual differences in semantic cognition. We tested this view by exploring how variation in intrinsic brain functional connectivity between semantic nodes in fMRI was related to performance on a battery of semantic tasks in 154 healthy participants. Through simultaneous decomposition of brain functional connectivity and semantic task performance, we identified distinct components of semantic cognition at rest. In a subsequent validation step, these data-driven components demonstrated explanatory power for neural responses in an fMRI-based semantic localiser task and variation in self-generated thoughts during the resting-state scan. Our findings showed that good performance on harder semantic tasks was associated with relative segregation at rest between frontal brain regions implicated in controlled semantic retrieval and the default mode network. Poor performance on easier tasks was linked to greater coupling between the same frontal regions and the anterior temporal lobe; a pattern associated with deliberate, verbal thematic thoughts at rest. We also identified components that related to qualities of semantic cognition: relatively good performance on pictorial semantic tasks was associated with greater separation of angular gyrus from frontal control sites and greater integration with posterior cingulate and anterior temporal cortex. In contrast, good speech production was linked to the separation of angular gyrus, posterior cingulate and temporal lobe regions. Together these data show that quantitative and qualitative variation in semantic

  16. Profile of clinically-diagnosed dementias in a neuropsychiatric ...

    African Journals Online (AJOL)

    Alzheimer's disease (AD) and Vascular dementia (VaD) were the predominant phenotypes seen in 62 (57.4%) and 18 (16.7%) subjects respectively. Others include mixed dementia (4 cases), frontotemporal dementia (4 cases), Lewy body dementia (3 cases), alcohol-related dementia (3 cases), PD dementia (1 case) and ...

  17. Application of textural features to the objective diagnosis of Alzheimer-type dementia

    International Nuclear Information System (INIS)

    Kodama, Naoki; Shimada, Tetsuo; Kaeriyama, Tomoharu; Kaneko, Tomoyuki; Fukumoto, Ichiro; Kobayashi, Yoshio

    2003-01-01

    In this study, patients with Alzheimer-type dementia were compared with healthy elderly individuals by means of 13 textural features to evaluate the application of these features to the objective diagnosis of the dementia. A statistically significant difference was found in 8 of the 13 textural features between dementia patients and healthy controls. Discriminant analysis using the eight features demonstrated a sensitivity of 91.2% and a specificity of 86.4%, with an overall accuracy of 89.1%. Multiple discriminant analysis using the eight features by dementia stage showed an overall accuracy of 78.2% for discrimination of four stages. These results indicate that quantitative textural feature measurements can be used as an objective diagnostic technique for Alzheimer-type dementia. (author)

  18. Benchmarking semantic web technology

    CERN Document Server

    García-Castro, R

    2009-01-01

    This book addresses the problem of benchmarking Semantic Web Technologies; first, from a methodological point of view, proposing a general methodology to follow in benchmarking activities over Semantic Web Technologies and, second, from a practical point of view, presenting two international benchmarking activities that involved benchmarking the interoperability of Semantic Web technologies using RDF(S) as the interchange language in one activity and OWL in the other.The book presents in detail how the different resources needed for these interoperability benchmarking activities were defined:

  19. Clinical diagnosis by computed tomography on Alzheimer type dementia

    Energy Technology Data Exchange (ETDEWEB)

    Imai, Yukimichi

    1983-09-01

    The relationships of CT findings, intellectual impairment by psychological assessment and severity of dementia by clinical evaluation were studied on 109 patients with clinical diagnosis of Alzheimer type dementia (AD) and 43 controls. CT examinations were carried out on three tomographic sections, that is, a section through anterior and posterior horns of lateral ventricles, a section through cellae mediae of lateral ventricles and a section through cortex with intracranial space of 60-80 cm/sup 2/. In the three tomographic sections, CSF space percent and half width full max (HWFM) in the histogram corresponding to brain tissue were employed as indexes of brain atrophy by CT. Psychological evaluation of dementia was made by using Hasegawa's dementia scale (HDS). The present study revealed the following findings. though CSF% in the sections through lateral ventricles significantly correlated with age, it was more significantly correlated with HDS and CDR(clinical dementia rating) scores, respectively. This finding seems to mean that the effect of dementia is so great as to override the effect of dementia. In the cortex slice, the correlations between CSF% and HDS and CDR scores were very low, though they were significant. HWFM in the same slice, showed the moderate and significant correlations with HDS and CDR scores, respectively, comparing with no relationship between HWFM and age. Concerning mean CSF% and HWFM of each group according to CDR staging, they increased with advancement of dementia. The significant differences between the groups by CDR, however, were not always obtained. According to CT indexes as independent variable, the normal subject were discriminated from the demented subjects in 82.6% of the total by discriminat analysis. (J.P.N.).

  20. Clinical diagnosis by computed tomography on Alzheimer type dementia

    International Nuclear Information System (INIS)

    Imai, Yukimichi

    1983-01-01

    The relationships of CT findings, intellectual impairment by psychological assessment and severity of dementia by clinical evaluation were studied on 109 patients with clinical diagnosis of Alzheimer type dementia (AD) and 43 controls. CT examinations were carried out on three tomographic sections, that is, a section through anterior and posterior horns of lateral ventricles, a section through cellae mediae of lateral ventricles and a section through cortex with intracranial space of 60-80 cm 2 . In the three tomographic sections, CSF space percent and half width full max (HWFM) in the histogram corresponding to brain tissue were employed as indexes of brain atrophy by CT. Psychological evaluation of dementia was made by using Hasegawa's dementia scale (HDS). The present study revealed the following findings. though CSF% in the sections through lateral ventricles significantly correlated with age, it was more significantly correlated with HDS and CDR(clinical dementia rating) scores, respectively. This finding seems to mean that the effect of dementia is so great as to override the effect of dementia. In the cortex slice, the correlations between CSF% and HDS and CDR scores were very low, though they were significant. HWFM in the same slice, showed the moderate and significant correlations with HDS and CDR scores, respectively, comparing with no relationship between HWFM and age. Concerning mean CSF% and HWFM of each group according to CDR staging, they increased with advancement of dementia. The significant differences between the groups by CDR, however, were not always obtained. According to CT indexes as independent variable, the normal subject were discriminated from the demented subjects in 82.6% of the total by discriminat analysis. (J.P.N.)

  1. Information adaptation the interplay between Shannon information and semantic information in cognition

    CERN Document Server

    Haken, Hermann

    2015-01-01

    This monograph demonstrates the interplay between Shannon information and semantic information in cognition. It shows that Shannon’s information acts as driving force for the formation of semantic information; and vice versa, namely, that semantic information participates in the formation of Shannonian information. The authors show that in cognition, Shannonian and semantic information are interrelated as two aspects of a cognitive process termed as information adaptation. In the latter the mind/brain adapts to the environment by the deflating and/or inflating of the information conveyed by the environment. In the process of information adaptation, quantitative variations in Shannon’s information entail different meanings while different meanings affect the quantity of information. The book illustrates the above conceptually and mathematically by reference to three cognitive processes: pattern recognition, face learning and the recognition of a moving object.

  2. Semantic Web and Contextual Information: Semantic Network Analysis of Online Journalistic Texts

    Science.gov (United States)

    Lim, Yon Soo

    This study examines why contextual information is important to actualize the idea of semantic web, based on a case study of a socio-political issue in South Korea. For this study, semantic network analyses were conducted regarding English-language based 62 blog posts and 101 news stories on the web. The results indicated the differences of the meaning structures between blog posts and professional journalism as well as between conservative journalism and progressive journalism. From the results, this study ascertains empirical validity of current concerns about the practical application of the new web technology, and discusses how the semantic web should be developed.

  3. Senile dementia of the Binswanger type: a vascular form of dementia in the elderly

    International Nuclear Information System (INIS)

    Roman, G.C.

    1987-01-01

    Computed tomography and magnetic resonance imaging in the elderly have demonstrated the common occurrence of deep white-matter lesions in the aging brain. These radiologic lesions (leukoaraiosis) may represent an early marker of dementia. At autopsy, an ischemic periventricular leukoencephalopathy (Binswanger's disease) has been found in most cases. The clinical spectrum of Binswanger's disease appears to range from asymptomatic radiologic lesions to dementia with focal deficits, frontal signs, pseudobulbar palsy, gait difficulties, and urinary incontinence. The name senile dementia of the Binswanger type (SDBT) is proposed for this poorly recognized, vascular form of subcortical dementia. The SDBT probably results from cortical disconnections most likely caused by hypoperfusion. In contrast, multi-infarct dementia is correlated with multiple large and small strokes that cause a loss of over 50 to 100 mL of brain volume. The periventricular white matter is a watershed area irrigated by long, penetrating medullary arteries. Risk factors for SDBT are small-artery diseases, such as hypertension and amyloid angiopathy, impaired autoregulation of cerebral blood flow in the elderly, and periventricular hypoperfusion due to cardiac failure, arrhythmias, and hypotension. The SDBT may be a potentially preventable and treatable form of dementia

  4. Semantic Keys and Reading

    Directory of Open Access Journals (Sweden)

    Zev bar-Lev

    2016-12-01

    Full Text Available Semantic Keys are elements (word-parts of written language that give an iconic, general representation of the whole word’s meaning. In written Sino-Japanese the “radical” or semantic components play this role. For example, the character meaning ‘woman, female’ is the Semantic Key of the character for Ma ‘Mama’ (alongside the phonetic component Ma, which means ‘horse’ as a separate character. The theory of semantic Keys in both graphic and phonemic aspects is called qTheory or nanosemantics. The most innovative aspect of the present article is the hypothesis that, in languages using alphabetic writing systems, the role of Semantic Key is played by consonants, more specifically the first consonant. Thus, L meaning ‘LIFT’ is the Semantic Key of English Lift, Ladle, Lofty, aLps, eLevator, oLympus; Spanish Leva, Lecantarse, aLto, Lengua; Arabic aLLah, and Hebrew① ªeL-ºaL ‘upto-above’ (the Israeli airline, Polish Lot ‘flight’ (the Polish airline; Hebrew ªeL, ªeLohim ‘God’, and haLLeluyah ‘praise-ye God’ (using Parallels, ‘Lift up God’. Evidence for the universality of the theory is shown by many examples drawn from various languages, including Indo-European Semitic, Chinese and Japanese. The theory reveals hundreds of relationships within and between languages, related and unrelated, that have been “Hiding in Plain Sight”, to mention just one example: the Parallel between Spanish Pan ‘bread’ and Mandarin Fan ‘rice’.

  5. Interpreting semantic clustering effects in free recall.

    Science.gov (United States)

    Manning, Jeremy R; Kahana, Michael J

    2012-07-01

    The order in which participants choose to recall words from a studied list of randomly selected words provides insights into how memories of the words are represented, organised, and retrieved. One pervasive finding is that when a pair of semantically related words (e.g., "cat" and "dog") is embedded in the studied list, the related words are often recalled successively. This tendency to successively recall semantically related words is termed semantic clustering (Bousfield, 1953; Bousfield & Sedgewick, 1944; Cofer, Bruce, & Reicher, 1966). Measuring semantic clustering effects requires making assumptions about which words participants consider to be similar in meaning. However, it is often difficult to gain insights into individual participants' internal semantic models, and for this reason researchers typically rely on standardised semantic similarity metrics. Here we use simulations to gain insights into the expected magnitudes of semantic clustering effects given systematic differences between participants' internal similarity models and the similarity metric used to quantify the degree of semantic clustering. Our results provide a number of useful insights into the interpretation of semantic clustering effects in free recall.

  6. A Diagnostic Model for Dementia in Clinical Practice-Case Methodology Assisting Dementia Diagnosis.

    Science.gov (United States)

    Londos, Elisabet

    2015-04-02

    Dementia diagnosis is important for many different reasons. Firstly, to separate dementia, or major neurocognitive disorder, from MCI (mild cognitive impairment), mild neurocognitive disorder. Secondly, to define the specific underlying brain disorder to aid treatment, prognosis and decisions regarding care needs and assistance. The diagnostic method of dementias is a puzzle of different data pieces to be fitted together in the best possible way to reach a clinical diagnosis. Using a modified case methodology concept, risk factors affecting cognitive reserve and symptoms constituting the basis of the brain damage hypothesis, can be visualized, balanced and reflected against test results as well as structural and biochemical markers. The model's origin is the case method initially described in Harvard business school, here modified to serve dementia diagnostics.

  7. The Determinants of Quality of Life of Nursing Home Residents with Young-Onset Dementia and the Differences between Dementia Subtypes

    NARCIS (Netherlands)

    Appelhof, Britt; Bakker, C.; Van Duinen-van den Ijssel, Jeannette C L; Zwijsen, Sandra A; Smalbrugge, Martin; Verhey, Frans R. J.; de Vugt, Marjolein E; Zuidema, Sytse U.; Koopnnans, Raymond T. C. M.

    Aims: The aims of this study are to (1) explore the determinants of quality of life (QoL) in nursing home residents with young-onset dementia (YOD), (2) investigate whether there are differences between dementia subtypes (Alzheimer dementia, vascular/mixed dementia, frontotemporal dementia, other)

  8. Snapshots for Semantic Maps

    National Research Council Canada - National Science Library

    Nielsen, Curtis W; Ricks, Bob; Goodrich, Michael A; Bruemmer, David; Few, Doug; Walton, Miles

    2004-01-01

    .... Semantic maps are a relatively new approach to information presentation. Semantic maps provide more detail about an environment than typical maps because they are augmented by icons or symbols that provide meaning for places or objects of interest...

  9. Towards Compatible and Interderivable Semantic Specifications for the Scheme Programming Language, Part I: Denotational Semantics, Natural Semantics, and Abstract Machines

    DEFF Research Database (Denmark)

    Danvy, Olivier

    2009-01-01

    We derive two big-step abstract machines, a natural semantics, and the valuation function of a denotational semantics based on the small-step abstract machine for Core Scheme presented by Clinger at PLDI'98. Starting from a functional implementation of this small-step abstract machine, (1) we fus...

  10. ABO Blood Group and Dementia Risk--A Scandinavian Record-Linkage Study.

    Directory of Open Access Journals (Sweden)

    Senthil K Vasan

    Full Text Available Dementia includes a group of neuro-degenerative disorders characterized by varying degrees of cognitive impairment. Recent data indicates that blood group AB is associated with impaired cognition in elderly patients. To date there are no large-scale studies that have examined the relationship between ABO blood group and dementia-related disorders in detail.We used data from the SCANDAT2 database that contains information on over 1.6 million blood donors from 1968 in Sweden and 1981 from Denmark. The database was linked with health outcomes data from nationwide patient and cause of death registers to investigate the relationship between blood groups and risk of different types of dementia. The incident rate ratios were estimated using log-linear Poisson regression models.Among 1,598,294 donors followed over 24 million person-years of observation we ascertained 3,615 cases of Alzheimer's disease, 1,842 cases of vascular dementia, and 9,091 cases of unspecified dementia. Overall, our study showed no association between ABO blood group and risk of Alzheimer's disease, vascular dementia or unspecified dementia. This was also true when analyses were restricted to donors aged 70 years or older except for a slight, but significantly decreased risk of all dementia combined in subjects with blood group A (IRR, 0.93; 95% confidence interval [CI], 0.88-0.98, compared to those with blood group O.Our results provide no evidence that ABO blood group influences the risk of dementia.

  11. Comparison of cognitive and neuropsychiatric profiles in hospitalised elderly medical patients with delirium, dementia and comorbid delirium–dementia

    Science.gov (United States)

    Leonard, Maeve; McInerney, Shane; McFarland, John; Condon, Candice; Awan, Fahad; O'Connor, Margaret; Reynolds, Paul; Meaney, Anna Maria; Adamis, Dimitrios; Dunne, Colum; Cullen, Walter; Trzepacz, Paula T; Meagher, David J

    2016-01-01

    Objectives Differentiation of delirium and dementia is a key diagnostic challenge but there has been limited study of features that distinguish these conditions. We examined neuropsychiatric and neuropsychological symptoms in elderly medical inpatients to identify features that distinguish major neurocognitive disorders. Setting University teaching hospital in Ireland. Participants and measures 176 consecutive elderly medical inpatients (mean age 80.6±7.0 years (range 60–96); 85 males (48%)) referred to a psychiatry for later life consultation-liaison service with Diagnostic and Statistical Manual of Mental Disorders (DSM) IV delirium, dementia, comorbid delirium–dementia and cognitively intact controls. Participants were assessed cross-sectionally with comparison of scores (including individual items) for the Revised Delirium Rating Scale (DRS-R98), Cognitive Test for Delirium (CTD) and Neuropsychiatric Inventory (NPI-Q). Results The frequency of neurocognitive diagnoses was delirium (n=50), dementia (n=32), comorbid delirium–dementia (n=62) and cognitively intact patients (n=32). Both delirium and comorbid delirium–dementia groups scored higher than the dementia group for DRS-R98 and CTD total scores, but all three neurocognitively impaired groups scored similarly in respect of total NPI-Q scores. For individual DRS-R98 items, delirium groups were distinguished from dementia groups by a range of non-cognitive symptoms, but only for impaired attention of the cognitive items. For the CTD, attention (p=0.002) and vigilance (p=0.01) distinguished between delirium and dementia. No individual CTD item distinguished between comorbid delirium–dementia and delirium. For the NPI-Q, there were no differences between the three neurocognitively impaired groups for any individual item severity. Conclusions The neurocognitive profile of delirium is similar with or without comorbid dementia and differs from dementia without delirium. Simple tests of attention and

  12. Internet-based screening for dementia risk.

    Science.gov (United States)

    Brandt, Jason; Sullivan, Campbell; Burrell, Larry E; Rogerson, Mark; Anderson, Allan

    2013-01-01

    The Dementia Risk Assessment (DRA) is an online tool consisting of questions about known risk factors for dementia, a novel verbal memory test, and an informant report of cognitive decline. Its primary goal is to educate the public about dementia risk factors and encourage clinical evaluation where appropriate. In Study 1, more than 3,000 anonymous persons over age 50 completed the DRA about themselves; 1,000 people also completed proxy reports about another person. Advanced age, lower education, male sex, complaints of severe memory impairment, and histories of cerebrovascular disease, Parkinson's disease, and brain tumor all contributed significantly to poor memory performance. A high correlation was obtained between proxy-reported decline and actual memory test performance. In Study 2, 52 persons seeking first-time evaluation at dementia clinics completed the DRA prior to their visits. Their responses (and those of their proxy informants) were compared to the results of independent evaluation by geriatric neuropsychiatrists. The 30 patients found to meet criteria for probable Alzheimer's disease, vascular dementia, or frontotemporal dementia differed on the DRA from the 22 patients without dementia (most other neuropsychiatric conditions). Scoring below criterion on the DRA's memory test had moderately high predictive validity for clinically diagnosed dementia. Although additional studies of larger clinical samples are needed, the DRA holds promise for wide-scale screening for dementia risk.

  13. Classification with an edge: Improving semantic image segmentation with boundary detection

    Science.gov (United States)

    Marmanis, D.; Schindler, K.; Wegner, J. D.; Galliani, S.; Datcu, M.; Stilla, U.

    2018-01-01

    We present an end-to-end trainable deep convolutional neural network (DCNN) for semantic segmentation with built-in awareness of semantically meaningful boundaries. Semantic segmentation is a fundamental remote sensing task, and most state-of-the-art methods rely on DCNNs as their workhorse. A major reason for their success is that deep networks learn to accumulate contextual information over very large receptive fields. However, this success comes at a cost, since the associated loss of effective spatial resolution washes out high-frequency details and leads to blurry object boundaries. Here, we propose to counter this effect by combining semantic segmentation with semantically informed edge detection, thus making class boundaries explicit in the model. First, we construct a comparatively simple, memory-efficient model by adding boundary detection to the SEGNET encoder-decoder architecture. Second, we also include boundary detection in FCN-type models and set up a high-end classifier ensemble. We show that boundary detection significantly improves semantic segmentation with CNNs in an end-to-end training scheme. Our best model achieves >90% overall accuracy on the ISPRS Vaihingen benchmark.

  14. Behavioural and magnetoencephalographic evidence for the interaction between semantic and episodic memory in healthy elderly subjects.

    Science.gov (United States)

    La Corte, Valentina; Dalla Barba, Gianfranco; Lemaréchal, Jean-Didier; Garnero, Line; George, Nathalie

    2012-10-01

    The relationship between episodic and semantic memory systems has long been debated. Some authors argue that episodic memory is contingent on semantic memory (Tulving 1984), while others postulate that both systems are independent since they can be selectively damaged (Squire 1987). The interaction between these memory systems is particularly important in the elderly, since the dissociation of episodic and semantic memory defects characterize different aging-related pathologies. Here, we investigated the interaction between semantic knowledge and episodic memory processes associated with faces in elderly subjects using an experimental paradigm where the semantic encoding of famous and unknown faces was compared to their episodic recognition. Results showed that the level of semantic awareness of items affected the recognition of those items in the episodic memory task. Event-related magnetic fields confirmed this interaction between episodic and semantic memory: ERFs related to the old/new effect during the episodic task were markedly different for famous and unknown faces. The old/new effect for famous faces involved sustained activities maximal over right temporal sensors, showing a spatio-temporal pattern partly similar to that found for famous versus unknown faces during the semantic task. By contrast, an old/new effect for unknown faces was observed on left parieto-occipital sensors. These findings suggest that the episodic memory for famous faces activated the retrieval of stored semantic information, whereas it was based on items' perceptual features for unknown faces. Overall, our results show that semantic information interfered markedly with episodic memory processes and suggested that the neural substrates of these two memory systems overlap.

  15. [Creative therapy options for patients with dementia--a systematic review].

    Science.gov (United States)

    Schmitt, B; Frölich, L

    2007-12-01

    The specifics of creative therapies aim at activating the creative potential of the patients in the sense of acceptance, orientation and coping with their illness "dementia" and at improving their quality of life. Creative therapies in the treatment of dementia offer the advantage of working with these patients, whose cognition and often also verbal communication skills are affected in a nonverbal way. This article presents a systematic review of studies and case studies, which could be found on the subject of the implementation of active creative therapies "music-, art-, drama- and dance-therapy" within the following databases (05/05): Medline, Psyndex Plus, PsychInfo and Cochrane. The search terms used were: "Creativ* and therapy and dementia and (stud*)", "Dance therapy and dementia", "Music therapy and dementia", "Drama therapy and dementia" and "Art therapy and dementia". As a result of this search we found seven quantitative evaluated controlled studies, three prae-post comparisons and three qualitative evaluated studies which have been finished since 1998. All of these studies included groups of at least three participants. Further reviews are mentioned in this article. This survey of studies on creative therapies for patients with dementia shows positive effects like the improvement of interaction skills. The data supplied thus supports the approach of using creative therapies in order to help patients accept dementia as their illness and finally to cope with it. The methodical approach to the registration of the therapies' effects and process-orientated contents of the therapy create a field of tension, leading to the request for a further development and validation of instruments, which allow the quantitative evaluation of parameters like liveliness, agility and interaction skills.

  16. Examining lateralized semantic access using pictures.

    Science.gov (United States)

    Lovseth, Kyle; Atchley, Ruth Ann

    2010-03-01

    A divided visual field (DVF) experiment examined the semantic processing strategies employed by the cerebral hemispheres to determine if strategies observed with written word stimuli generalize to other media for communicating semantic information. We employed picture stimuli and vary the degree of semantic relatedness between the picture pairs. Participants made an on-line semantic relatedness judgment in response to sequentially presented pictures. We found that when pictures are presented to the right hemisphere responses are generally more accurate than the left hemisphere for semantic relatedness judgments for picture pairs. Furthermore, consistent with earlier DVF studies employing words, we conclude that the RH is better at accessing or maintaining access to information that has a weak or more remote semantic relationship. We also found evidence of faster access for pictures presented to the LH in the strongly-related condition. Overall, these results are consistent with earlier DVF word studies that argue that the cerebral hemispheres each play an important and separable role during semantic retrieval. Copyright 2009 Elsevier Inc. All rights reserved.

  17. WEATHER FORECAST DATA SEMANTIC ANALYSIS IN F-LOGIC

    Directory of Open Access Journals (Sweden)

    Ana Meštrović

    2007-06-01

    Full Text Available This paper addresses the semantic analysis problem in a spoken dialog system developed for the domain of weather forecasts. The main goal of semantic analysis is to extract the meaning from the spoken utterances and to transform it into a domain database format. In this work a semantic database for the domain of weather forecasts is represented using the F-logic formalism. Semantic knowledge is captured through semantic categories a semantic dictionary using phrases and output templates. Procedures for semantic analysis of Croatian weather data combine parsing techniques for Croatian language and slot filling approach. Semantic analysis is conducted in three phases. In the first phase the main semantic category for the input utterance is determined. The lattices are used for hierarchical semantic relation representation and main category derivation. In the second phase semantic units are analyzed and knowledge slots in the database are filled. Since some slot values of input data are missing in the third phase, incomplete data is updated with missing values. All rules for semantic analysis are defined in the F-logic and implemented using the FLORA-2 system. The results of semantic analysis evaluation in terms of frame and slot error rates are presented.

  18. CASL The Common Algebraic Specification Language Semantics

    DEFF Research Database (Denmark)

    Haxthausen, Anne

    1998-01-01

    This is version 1.0 of the CASL Language Summary, annotated by the CoFI Semantics Task Group with the semantics of constructs. This is the first complete but possibly imperfect version of the semantics. It was compiled prior to the CoFI workshop at Cachan in November 1998.......This is version 1.0 of the CASL Language Summary, annotated by the CoFI Semantics Task Group with the semantics of constructs. This is the first complete but possibly imperfect version of the semantics. It was compiled prior to the CoFI workshop at Cachan in November 1998....

  19. Cognitive Profiles in Patients with Multi-Infarct Dementia: An Omani Study

    Directory of Open Access Journals (Sweden)

    Samir Al-Adawi

    2014-07-01

    Full Text Available Background: Studies on neurocognitive impairment among patients presenting with multi-infarct dementia (MID have received little attention from non-Western societies, and the Arab world is no exception. To our knowledge, this is the first study to characterize neurocognitive, affective and vegetative functioning in patients with MID in Oman. Methods: In this study, we recruited 20 Omani patients presenting with MID and age- and gender-matched controls at the outpatient clinic of the Department of Behavioral Medicine, Sultan Qaboos University Hospital, Sultan Qaboos University, Muscat, Oman. In addition to the collection of clinical and demographic information, various cognitive batteries were administered to the consenting participants, including those indexing nonverbal reasoning abilities, working memory (attention, concentration and recall and executive functioning. Questionnaires that elicit the affective range and the quality of sleep were also administered. Results: Compared with the matched healthy subjects, the patients diagnosed with MID significantly differed in the presently operationalized indices of visuospatial function, semantic memory and affective and vegetative functioning. In contrast, episodic memory and some attentional capacities were not significantly different compared with the control subjects. Conclusions: The present study was explorative and clinically designed to describe neurocognitive functioning in patients with MID seeking consultation at a tertiary care center in Oman. Our data are necessary for planning and setting up community services and health care programs for demented patients in a society where dementia is a growing silent epidemic. © 2014 S. Karger AG, Basel

  20. Semantic Web status model

    CSIR Research Space (South Africa)

    Gerber, AJ

    2006-06-01

    Full Text Available Semantic Web application areas are experiencing intensified interest due to the rapid growth in the use of the Web, together with the innovation and renovation of information content technologies. The Semantic Web is regarded as an integrator across...

  1. Interdependence of episodic and semantic memory: evidence from neuropsychology.

    Science.gov (United States)

    Greenberg, Daniel L; Verfaellie, Mieke

    2010-09-01

    Tulving's (1972) theory of memory draws a distinction between general knowledge (semantic memory) and memory for events (episodic memory). Neuropsychological studies have generally examined each type of memory in isolation, but theorists have long argued that these two forms of memory are interdependent. Here we review several lines of neuropsychological research that have explored the interdependence of episodic and semantic memory. The studies show that these forms of memory can affect each other both at encoding and at retrieval. We suggest that theories of memory should be revised to account for all of the interdependencies between episodic and semantic memory; they should also incorporate forms of memory that do not fit neatly into either category.

  2. The Semantic Web: From Representation to Realization

    Science.gov (United States)

    Thórisson, Kristinn R.; Spivack, Nova; Wissner, James M.

    A semantically-linked web of electronic information - the Semantic Web - promises numerous benefits including increased precision in automated information sorting, searching, organizing and summarizing. Realizing this requires significantly more reliable meta-information than is readily available today. It also requires a better way to represent information that supports unified management of diverse data and diverse Manipulation methods: from basic keywords to various types of artificial intelligence, to the highest level of intelligent manipulation - the human mind. How this is best done is far from obvious. Relying solely on hand-crafted annotation and ontologies, or solely on artificial intelligence techniques, seems less likely for success than a combination of the two. In this paper describe an integrated, complete solution to these challenges that has already been implemented and tested with hundreds of thousands of users. It is based on an ontological representational level we call SemCards that combines ontological rigour with flexible user interface constructs. SemCards are machine- and human-readable digital entities that allow non-experts to create and use semantic content, while empowering machines to better assist and participate in the process. SemCards enable users to easily create semantically-grounded data that in turn acts as examples for automation processes, creating a positive iterative feedback loop of metadata creation and refinement between user and machine. They provide a holistic solution to the Semantic Web, supporting powerful management of the full lifecycle of data, including its creation, retrieval, classification, sorting and sharing. We have implemented the SemCard technology on the semantic Web site Twine.com, showing that the technology is indeed versatile and scalable. Here we present the key ideas behind SemCards and describe the initial implementation of the technology.

  3. Using semantic memory to boost 'episodic' recall in a case of developmental amnesia.

    Science.gov (United States)

    Brandt, Karen R; Gardiner, John M; Vargha-Khadem, Faraneh; Baddeley, Alan D; Mishkin, Mortimer

    2006-07-17

    We report two experiments that investigated factors that might boost 'episodic' recall for Jon, a developmental amnesic whose episodic memory is gravely impaired but whose semantic memory seems relatively normal. Experiment 1 showed that Jon's recall improved following a semantic study task compared with a non-semantic study task, as well as following four repeated study trials compared with only one. Experiment 2 additionally revealed that Jon's recall improved after acting compared with reading action phrases at study, but only if the phrases were well integrated semantically. The results provide some support for the hypothesis that Jon's 'episodic' recall depends on the extent to which he is able to retrieve events using semantic memory.

  4. Complement activation in chromosome 13 dementias

    DEFF Research Database (Denmark)

    Rostagno, A.; Revesz, T.; Lashley, T.

    2002-01-01

    Chromosome 13 dementias, familial British dementia (FBD) and familial Danish dementia (FDD), are associated with neurodegeneration and cerebrovascular amyloidosis, with striking neuropathological similarities to Alzheimer's disease (AD). Despite the structural differences among the amyloid subunits...

  5. Dementia: Diagnosis and Tests

    Science.gov (United States)

    ... our e-newsletter! Aging & Health A to Z Dementia Diagnosis & Tests If you or someone you care ... To determine whether an older adult might have dementia, a healthcare professional will: Ask about the person’s ...

  6. Minimally inconsistent reasoning in Semantic Web.

    Science.gov (United States)

    Zhang, Xiaowang

    2017-01-01

    Reasoning with inconsistencies is an important issue for Semantic Web as imperfect information is unavoidable in real applications. For this, different paraconsistent approaches, due to their capacity to draw as nontrivial conclusions by tolerating inconsistencies, have been proposed to reason with inconsistent description logic knowledge bases. However, existing paraconsistent approaches are often criticized for being too skeptical. To this end, this paper presents a non-monotonic paraconsistent version of description logic reasoning, called minimally inconsistent reasoning, where inconsistencies tolerated in the reasoning are minimized so that more reasonable conclusions can be inferred. Some desirable properties are studied, which shows that the new semantics inherits advantages of both non-monotonic reasoning and paraconsistent reasoning. A complete and sound tableau-based algorithm, called multi-valued tableaux, is developed to capture the minimally inconsistent reasoning. In fact, the tableaux algorithm is designed, as a framework for multi-valued DL, to allow for different underlying paraconsistent semantics, with the mere difference in the clash conditions. Finally, the complexity of minimally inconsistent description logic reasoning is shown on the same level as the (classical) description logic reasoning.

  7. Features of the Japanese national dementia strategy in comparison with international dementia policies: How should a national dementia policy interact with the public health- and social-care systems?

    Science.gov (United States)

    Nakanishi, Miharu; Nakashima, Taeko

    2014-07-01

    The Ministry of Health, Labour, and Welfare of the Japanese national government announced a "Five-Year Plan for Promotion of Measures Against Dementia (Orange Plan)" in September 2012. This article described features of the Japanese dementia strategy in comparison with international dementia policies. An international comparative study was implemented on national dementia policies to seek suggestions for Japanese national strategy. The study consisted of a bibliographical survey, a field survey, and an online case vignette survey in several countries. The Japanese health- and social-care system had multiple access points in the dementia care pathway, as did Australia, France, South Korea, and the Netherlands. Contrary to Japan, a simplified access point was observed in Denmark, England, and Sweden. The Orange Plan aimed to establish specific health-care services, social-care services, and the coordination of agencies for persons with dementia. However, fragmentation remains in the dementia care pathway. The national government should examine fundamental revisions in health, social-care services, and advocacy in joint initiatives with Alzheimer's Association Japan to improve the national dementia strategy. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  8. Dementia caregivers' responses to 2 Internet-based intervention programs.

    Science.gov (United States)

    Marziali, Elsa; Garcia, Linda J

    2011-02-01

    The aim of this study was to examine the impact on dementia caregivers' experienced stress and health status of 2 Internet-based intervention programs. Ninety-one dementia caregivers were given the choice of being involved in either an Internet-based chat support group or an Internet-based video conferencing support group. Pre-post outcome measures focused on distress, health status, social support, and service utilization. In contrast to the Chat Group, the Video Group showed significantly greater improvement in mental health status. Also, for the Video Group, improvements in self-efficacy, neuroticism, and social support were associated with lower stress response to coping with the care recipient's cognitive impairment and decline in function. The results show that, of 2 Internet-based intervention programs for dementia caregivers, the video conferencing intervention program was more effective in improving mental health status and improvement in personal characteristics were associated with lower caregiver stress response.

  9. Hippocampal activation during retrieval of spatial context from episodic and semantic memory.

    Science.gov (United States)

    Hoscheidt, Siobhan M; Nadel, Lynn; Payne, Jessica; Ryan, Lee

    2010-10-15

    The hippocampus, a region implicated in the processing of spatial information and episodic memory, is central to the debate concerning the relationship between episodic and semantic memory. Studies of medial temporal lobe amnesic patients provide evidence that the hippocampus is critical for the retrieval of episodic but not semantic memory. On the other hand, recent neuroimaging studies of intact individuals report hippocampal activation during retrieval of both autobiographical memories and semantic information that includes historical facts, famous faces, and categorical information, suggesting that episodic and semantic memory may engage the hippocampus during memory retrieval in similar ways. Few studies have matched episodic and semantic tasks for the degree to which they include spatial content, even though spatial content may be what drives hippocampal activation during semantic retrieval. To examine this issue, we conducted a functional magnetic resonance imaging (fMRI) study in which retrieval of spatial and nonspatial information was compared during an episodic and semantic recognition task. Results show that the hippocampus (1) participates preferentially in the retrieval of episodic memories; (2) is also engaged by retrieval of semantic memories, particularly those that include spatial information. These data suggest that sharp dissociations between episodic and semantic memory may be overly simplistic and that the hippocampus plays a role in the retrieval of spatial content whether drawn from a memory of one's own life experiences or real-world semantic knowledge. Published by Elsevier B.V.

  10. Depression and the risk for dementia

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel

    2012-01-01

    Depression is associated with increased risk of subsequent development of dementia; however, the nature of the association is still poorly understood. The purpose of the review was based on recent studies to discuss whether depression is a prodromal state of dementia or an independent risk factor...... for dementia, as well as to discuss how the type of depression, the type of dementia, and antidepressant treatment influence the association....

  11. Two books on dementia care: Risk Assessment and management for living well with dementia, and Key issues in evolving dementia care

    Directory of Open Access Journals (Sweden)

    Gillian Manthorpe

    2013-05-01

    Full Text Available Risk Assessment and Management for Living Well with Dementia. Charlotte L. Clarke, Heather Wilkinson, John Keady and Catherine E. Gibb. Foreword by Murna Downs. Part of the Bradford Dementia Group Good Practice Guides series. London: Jessica Kingsley Publishers, 2011, pp. 128, ISBN: 978-1-84905-005-0Key Issues in Evolving Dementia Care. International Theory-based Policy and Practice. Edited by Anthea Innes, Fiona Kelly and Louise McCabe. Foreword by Professor June Andrews. London: Jessica Kingsley Publishers, 2012, pp. 264, ISBN: 978-1-84905-242-9

  12. A Denotational Semantics for Communicating Unstructured Code

    Directory of Open Access Journals (Sweden)

    Nils Jähnig

    2015-03-01

    Full Text Available An important property of programming language semantics is that they should be compositional. However, unstructured low-level code contains goto-like commands making it hard to define a semantics that is compositional. In this paper, we follow the ideas of Saabas and Uustalu to structure low-level code. This gives us the possibility to define a compositional denotational semantics based on least fixed points to allow for the use of inductive verification methods. We capture the semantics of communication using finite traces similar to the denotations of CSP. In addition, we examine properties of this semantics and give an example that demonstrates reasoning about communication and jumps. With this semantics, we lay the foundations for a proof calculus that captures both, the semantics of unstructured low-level code and communication.

  13. A Semantics for Distributed Execution of Statemate

    DEFF Research Database (Denmark)

    Fränzle, Martin; Niehaus, Jürgen; Metzner, Alexander

    2003-01-01

    We present a semantics for the statechart variant implemented in the Statemate product of i-Logix. Our semantics enables distributed code generation for Statemate models in the context of rapid prototyping for embedded control applications. We argue that it seems impossible to efficiently generate......, the changes made regarding the interaction of distributed model parts are similar to the interaction between the model and its environment in the original semantics, thus giving designers a familiar execution model. The semantics has been implemented in Grace, a framework for rapid prototyping code generation...... distributed code using the original Statemate semantics. The new, distributed semantics has the advantages that, first, it enables the generation of efficient distributed code, second, it preserves many aspects of the original semantics for those parts of a model that are not distributed, and third...

  14. Inter-deriving Semantic Artifacts for Object-Oriented Programming

    DEFF Research Database (Denmark)

    Danvy, Olivier; Johannsen, Jacob

    2008-01-01

    .e., big-step operational semantics) specified in Abadi and Cardelli's monograph. This abstract machine therefore embodies the soundness of Abadi and Cardelli's reduction semantics and natural semantics relative to each other. To move closer to actual implementations, which use environments rather than......We present a new abstract machine for Abadi and Cardelli's untyped calculus of objects. What is special about this semantic artifact (i.e., man-made construct) is that is mechanically corresponds to both the reduction semantics (i.e., small-step operational semantics) and the natural semantics (i...... actual substitutions, we then represent object methods as closures and in the same inter-derivational spirit, we present three new semantic artifacts: a reduction semantics for a version of Abadi and Cardelli's untyped calculus of objects with explicit substitutions, an environment-based abstract machine...

  15. Antioxidants and Dementia Risk: Consideration through a Cerebrovascular Perspective

    Directory of Open Access Journals (Sweden)

    Virginie Lam

    2016-12-01

    Full Text Available A number of natural and chemical compounds that exert anti-oxidative properties are demonstrated to be beneficial for brain and cognitive function, and some are reported to reduce the risk of dementia. However, the detailed mechanisms by which those anti-oxidative compounds show positive effects on cognition and dementia are still unclear. An emerging body of evidence suggests that the integrity of the cerebrovascular blood-brain barrier (BBB is centrally involved in the onset and progression of cognitive impairment and dementia. While recent studies revealed that some anti-oxidative agents appear to be protective against the disruption of BBB integrity and structure, few studies considered the neuroprotective effects of antioxidants in the context of cerebrovascular integrity. Therefore, in this review, we examine the mechanistic insights of antioxidants as a pleiotropic agent for cognitive impairment and dementia through a cerebrovascular axis by primarily focusing on the current available data from physiological studies. Conclusively, there is a compelling body of evidence that suggest antioxidants may prevent cognitive decline and dementia by protecting the integrity and function of BBB and, indeed, further studies are needed to directly examine these effects in addition to underlying molecular mechanisms.

  16. I-123 iodoamphetamine brain SPECT of leukoencephalopathy in dementia

    International Nuclear Information System (INIS)

    Kramer, E.L.; George, A.E.; Sanger, J.J.; De Leon, M.J.

    1987-01-01

    Six elderly patients with dementia underwent I-123 iodoamphetamine (IMP) SPECT and CT or MR imaging of the brain. In five of six, CT or MR imaging showed changes in the temporal lobes consistent with Alzheimer disease (AD). IMP scans in these five showed temporal and parietal defects. In five of six, CT or MR imaging showed white-matter lucencies and/or basal ganglia infarcts. In these, IMP defects corresponded to focal CT abnormalities but were more extensive and also involved structural normal adjacent cortex. IMP demonstrates the deficits of AD and leukoencephalopathy and may help clarify the contribution of small-vessel disease to dementia in the elderly

  17. Quality of semantic standards

    NARCIS (Netherlands)

    Folmer, Erwin Johan Albert

    2012-01-01

    Little scientific literature addresses the issue of quality of semantic standards, albeit a problem with high economic and social impact. Our problem survey, including 34 semantic Standard Setting Organizations (SSOs), gives evidence that quality of standards can be improved, but for improvement a

  18. Teaching Mands to Older Adults with Dementia

    Science.gov (United States)

    Oleson, Chelsey R.; Baker, Jonathan C.

    2014-01-01

    Millions of Americans are diagnosed with dementia, and that number is only expected to rise. The diagnosis of dementia comes with impairments, especially in language. Furthermore, dementia-related functional declines appear to be moderated by environmental variables (Alzheimer's Association, "Alzheimer's & Dementia: The Journal of the…

  19. Beyond competence: advance directives in dementia research

    NARCIS (Netherlands)

    K.R. Jongsma (Karin); S. van de Vathorst (Suzanne)

    2015-01-01

    textabstractDementia is highly prevalent and incurable. The participation of dementia patients in clinical research is indispensable if we want to find an effective treatment for dementia. However, one of the primary challenges in dementia research is the patients’ gradual loss of the capacity to

  20. Dementia RED (Respect Empathy Dignity): Collaborating to build dementia supportive communities in North Wales--reporting on a pilot project (innovative practice).

    Science.gov (United States)

    Chalk, Annabel; Page, Sean

    2016-03-01

    There is increasing interest in developing dementia supportive communities world wide. Dementia RED (Respect Empathy Dignity) is a unique example from North Wales which is based on the twin concepts of people living with dementia as citizens in their community and developing 'bottom up' rather than 'top down' approaches to dementia supportive communities. Most people with dementia prefer to live at home thus making community connectivity key to maintaining healthy relationships and wellbeing. For those living with dementia, the community plays a pivotal role in providing value, meaning, purpose and acceptance. Building dementia supportive communities helps to raise awareness about dementia in the community through engagement and from identifying champions in the locality to voice issues. Dementia RED is an initiative and service which helps to develop such a philosophy in creating a dementia supportive community. © The Author(s) 2014.

  1. Morphological Cues for Lexical Semantics

    National Research Council Canada - National Science Library

    Light, Marc

    1996-01-01

    Most natural language processing tasks require lexical semantic information such as verbal argument structure and selectional restrictions, corresponding nominal semantic class, verbal aspectual class...

  2. Dementia in middle-aged patients with schizophrenia.

    Science.gov (United States)

    Nicolas, Gaël; Beherec, Laurène; Hannequin, Didier; Opolczynski, Gaëlle; Rothärmel, Maud; Wallon, David; Véra, Pierre; Martinaud, Olivier; Guillin, Olivier; Campion, Dominique

    2014-01-01

    Although numerous studies have assessed cognitive dysfunction in patients with schizophrenia, very few have focused on the diagnosis of dementia. Our objectives were to accurately diagnose dementia in a cohort of middle-aged patients with schizophrenia and to assess the type of dementia. 96 patients with schizophrenia (46 inpatients and 50 outpatients), aged 50 to 70 years, underwent a psychiatric, neurological, and neuropsychological evaluation at baseline and after a 20-month follow-up. We established a 3-step procedure: 1) diagnose dementia according to the DSM-IV criteria, using the Mattis Dementia Rating and Activities of Daily Living scales; 2) characterize dementia using brain imaging, perfusion by 99mTc-ECD-SPECT and laboratory tests including Alzheimer's disease cerebrospinal fluid biomarkers; and 3) search for genetic determinants. Fourteen patients fulfilled the diagnostic criteria of dementia. Four were diagnosed with possible or probable behavioral-variant frontotemporal dementia (bvFTD), two with probable Alzheimer's disease, two with probable vascular dementia (including one due to CADASIL), one with CNS inflammatory disease, and six could not be fully characterized. The diagnosis of dementia in middle-aged patients with schizophrenia is challenging but possible, using a multistep procedure. The most frequent condition, bvFTD, could reflect the presence of an evolutive neurodegenerative process in some patients.

  3. Longitudinal Association of Dementia and Depression.

    Science.gov (United States)

    Snowden, Mark B; Atkins, David C; Steinman, Lesley E; Bell, Janice F; Bryant, Lucinda L; Copeland, Catherine; Fitzpatrick, Annette L

    2015-09-01

    Depression is an important precursor to dementia, but less is known about the role dementia plays in altering the course of depression. We examined whether depression prevalence, incidence, and severity are higher in those with dementia versus those with mild cognitive impairment (MCI), or normal cognition. Prospective cohort study using the longitudinal Uniform Data Set of the National Alzheimer's Coordinating Center (2005-2013). 34 Alzheimer Disease research centers. 27,776 subjects with dementia, MCI, or normal cognition. Depression status was determined by a clinical diagnosis of depression within the prior 2 years and by a Geriatric Depression Scale-Short Form score >5. Rates of depression were significantly higher in subjects with MCI and dementia compared with those with normal cognition at index visit. Controlling for demographics and common chronic conditions, logistic regression analysis revealed elevated depression in those with MCI (OR: 2.40 [95% CI: 2.25, 2.56]) or dementia (OR: 2.64 [95% CI: 2.43, 2.86]) relative to those with normal cognition. In the subjects without depression at the index visit (N = 18,842), those with MCI and dementia had higher probabilities of depression diagnosis 2 years post index visit than those with normal cognition: MCI = 21.7%, dementia = 24.7%, normal cognition = 10.5%. MCI and dementia were associated with significantly higher rates of depression in concurrent as well as prospective analyses. These findings suggest that efforts to effectively engage and treat older adults with dementia will need also to address co-occurring depression. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  4. Arbitrary and semantic associations in subjective memory impairment and amnestic mild cognitive impairment among Taiwanese individuals: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Hsin-Te Chang

    2018-05-01

    Full Text Available Background/Purpose: Researchers have recently proposed a preclinical stage of dementia of Alzheimer's type (DAT, referred to as subjective memory impairment (SMI, with the aim of developing methods for the early detection of DAT and subsequent intervention. It has been proposed that the objective memory functions of individuals with SMI are normal; however, arbitrary and semantic associations are both used to describe the processes of memory. No previous studies have investigated these processes among individuals with SMI. Methods: Cross-sectional analysis was used to compare the memory function of individuals with SMI, amnestic mild cognitive impairment (aMCI, or DAT. One hundred and eighty-three participants were recruited from the Memory Clinic of National Taiwan University Hospital and communities in northern Taiwan, including individuals with no memory complaints (HC, n = 30 and individuals with SMI (n = 61, aMCI-single domain (n = 24, aMCI-multiple domain (n = 33, or DAT (n = 35. The Word Sequence Learning Test (WSLT was used to assess the formation of arbitrary associations and the Logical Memory subtest of the Wechsler Memory Scale-Third Edition was used to assess the formation of semantic associations. Results: Compared to the HC group, the SMI group performed poorly only on the WSLT, whereas the other groups performed poorly on both of the memory tasks. This study demonstrated that SMI individuals tend to perform poorly in the formation of arbitrary associations. Conclusion: Our findings suggest that tasks requiring arbitrary associations may provide greater sensitivity in the detection cognitive changes associated with preclinical DAT. Keywords: Alzheimer's disease, Mild cognitive impairment, Neuropsychology, Dementia

  5. Dementia quality of life instrument--construct and concurrent validity in patients with mild to moderate dementia.

    NARCIS (Netherlands)

    Voigt-Radloff, S.; Leonhart, R.; Schutzwohl, M.; Jurjanz, L.; Reuster, T.; Gerner, A.; Marschner, K.; Nes, F. van; Graff, M.J.; Vernooij-Dassen, M.J.F.J.; Olde Rikkert, M.G.; Holthoff, V.; Hull, M.

    2012-01-01

    BACKGROUND AND PURPOSE: To translate the Dementia quality of life instrument (DQoL) into German and assess its construct and concurrent validity in community-dwelling people with mild to moderate dementia. METHODS: Dementia quality of life instrument data of two pooled samples (n=287) were analysed

  6. Dementia quality of life instrument - construct and concurrent validity in patients with mild to moderate dementia

    NARCIS (Netherlands)

    Voigt-Radloff, S.; Leonhart, R.; Schutzwohl, M.; Jurjanz, L.; Reuster, T.; Gerner, A.; Marschner, K.; van Nes, F.A.; Graff, M.; Vernooij-Dassen, M.; Olde Rikkert, M.G.M.; Holthoff, V.; Hull, M.

    2012-01-01

    Background and purpose: To translate the Dementia quality of life instrument (DQoL) into German and assess its construct and concurrent validity in community-dwelling people with mild to moderate dementia. Methods: Dementia quality of life instrument data of two pooled samples (n=287) were analysed

  7. Survival in the pre-senile dementia frontotemporal lobar degeneration with TDP-43 proteinopathy: effects of genetic, demographic and neuropathological variables

    Directory of Open Access Journals (Sweden)

    Richard A. Armstrong

    2016-06-01

    Full Text Available Factors associated with survival were studied in 84 neuropathologically documented cases of the pre-senile dementia frontotemporal dementia lobar degeneration (FTLD with transactive response (TAR DNA-binding protein of 43 kDa (TDP-43 proteinopathy (FTLD-TDP. Kaplan-Meier survival analysis estimated mean survival as 7.9 years (range: 1-19 years, SD = 4.64. Familial and sporadic cases exhibited similar survival, including progranulin (GRN gene mutation cases. No significant differences in survival were associated with sex, disease onset, Braak disease stage, or disease subtype, but higher survival was associated with lower post-mortem brain weight. Survival was significantly reduced in cases with associated motor neuron disease (FTLD-MND but increased with Alzheimer’s disease (AD or hippocampal sclerosis (HS co-morbidity. Cox regression analysis suggested that reduced survival was associated with increased densities of neuronal cytoplasmic inclusions (NCI while increased survival was associated with greater densities of enlarged neurons (EN in the frontal and temporal lobes. The data suggest that: (1 survival in FTLD-TDP is more prolonged than typical in pre-senile dementia but shorter than some clinical subtypes such as the semantic variant of primary progressive aphasia (svPPA, (2 MND co-morbidity predicts poor survival, and (3 NCI may develop early and EN later in the disease. The data have implications for both neuropathological characterization and subtyping of FTLD-TDP.

  8. Clinical features and multidisciplinary approaches to dementia care

    Directory of Open Access Journals (Sweden)

    Gr

    2011-05-01

    Full Text Available Jacob HG Grand¹, Sienna Caspar², Stuart WS MacDonald11Department of Psychology, University of Victoria, Victoria, BC, Canada; 2Interdisciplinary Graduate Studies, University of British Columbia, Vancouver, BC, CanadaAbstract: Dementia is a clinical syndrome of widespread progressive deterioration of cognitive abilities and normal daily functioning. These cognitive and behavioral impairments pose considerable challenges to individuals with dementia, along with their family members and caregivers. Four primary dementia classifications have been defined according to clinical and research criteria: 1 Alzheimer’s disease; 2 vascular dementias; 3 frontotemporal dementias; and 4 dementia with Lewy bodies/Parkinson’s disease dementia. The cumulative efforts of multidisciplinary healthcare teams have advanced our understanding of dementia beyond basic descriptions, towards a more complete elucidation of risk factors, clinical symptoms, and neuropathological correlates. The characterization of disease subtypes has facilitated targeted management strategies, advanced treatments, and symptomatic care for individuals affected by dementia. This review briefly summarizes the current state of knowledge and directions of dementia research and clinical practice. We provide a description of the risk factors, clinical presentation, and differential diagnosis of dementia. A summary of multidisciplinary team approaches to dementia care is outlined, including management strategies for the treatment of cognitive impairments, functional deficits, and behavioral and psychological symptoms of dementia. The needs of individuals with dementia are extensive, often requiring care beyond traditional bounds of medical practice, including pharmacologic and non-pharmacologic management interventions. Finally, advanced research on the early prodromal phase of dementia is reviewed, with a focus on change-point models, trajectories of cognitive change, and threshold models of

  9. What do people with dementia and their carers want to know about neuroimaging for dementia?

    Science.gov (United States)

    Featherstone, Hannah; Butler, Marie-Louise; Ciblis, Aurelia; Bokde, Arun L; Mullins, Paul G; McNulty, Jonathan P

    2017-05-01

    Neuroimaging forms an important part of dementia diagnosis. Provision of information on neuroimaging to people with dementia and their carers may aid understanding of the pathological, physiological and psychosocial changes of the disease, and increase understanding of symptoms. This qualitative study aimed to investigate participants' knowledge of the dementia diagnosis pathway, their understanding of neuroimaging and its use in diagnosis, and to determine content requirements for a website providing neuroimaging information. Structured interviews and a focus group were conducted with carers and people with dementia. The findings demonstrate an unmet need for information on neuroimaging both before and after the examination. Carers were keen to know about neuroimaging at a practical and technical level to help avoid diagnosis denial. People with dementia requested greater information, but with a caveat to avoid overwhelming detail, and were less likely to favour an Internet resource.

  10. Sexuality, aging, and dementia.

    Science.gov (United States)

    Benbow, Susan Mary; Beeston, Derek

    2012-07-01

    Sexuality in later life and its relationship to dementia is a neglected topic: greater understanding of the area has the potential to contribute to the quality of life of people with dementia, their family members, and formal carers. We review current knowledge about sexuality, aging, and dementia. We undertook a review of the recent literature to examine of the following areas: what is known about sexuality and aging, and about attitudes to sexuality and aging; what is known about the relevance of sexuality and aging to people living with dementia and their care; and the management of sexual behaviors causing concern to others. Sexual activity decreases in frequency with increasing age but many older people remain sexually active; there is no age limit to sexual responsiveness; and sexuality is becoming more important to successive cohorts of older people, including people living with dementia and gay, lesbian, bisexual, and transgendered elderly people. Attitudes and beliefs toward sexuality and aging are strongly influenced by stereotypes and myths, not only among the general public but also among those working in health and social care. Professional bodies should include sexuality, aging, and dementia in their training curricula. More work is needed on the impact of environmental issues, particularly in group living situations, on older adults' sexuality, and on consent issues. Ethical decision-making frameworks can be useful in practice. Organizations should investigate how to support staff in avoiding a problem-orientated approach and focus on providing holistic person-centered care.

  11. Measurement of semantic similarity for land use and land cover classification systems

    Science.gov (United States)

    Deng, Dongpo

    2008-12-01

    Land use and land cover (LULC) data is essential to environmental and ecological research. However, semantic heterogeneous of land use and land cover classification are often resulted from different data resources, different cultural contexts, and different utilities. Therefore, there is need to develop a method to measure, compare and integrate between land cover categories. To understand the meaning and the use of terminology from different domains, the common ontology approach is used to acquire information regarding the meaning of terms, and to compare two terms to determine how they might be related. Ontology is a formal specification of a shared conceptualization of a domain of interest. LULC classification system is a ontology. The semantic similarity method is used to compare to entities of three LULC classification systems: CORINE (European Environmental Agency), Oregon State, USA), and Taiwan. The semantic properties and relations firstly have been extracted from their definitions of LULC classification systems. Then semantic properties and relations of categories in three LULC classification systems are mutually compared. The visualization of semantic proximity is finally presented to explore the similarity or dissimilarity of data. This study shows the semantic similarity method efficiently detect semantic distance in three LULC classification systems and find out the semantic similar objects.

  12. Semantic Query Processing : Estimating Relational Purity

    NARCIS (Netherlands)

    Kalo, Jan-Christoph; Lofi, C.; Maseli, René Pascal; Balke, Wolf-Tilo; Leyer, M.

    2017-01-01

    The use of semantic information found in structured knowledge bases has become an integral part of the processing pipeline of modern intelligent in-
    formation systems. However, such semantic information is frequently insuffi-cient to capture the rich semantics demanded by the applications, and

  13. Comparison of cognitive and neuropsychiatric profiles in hospitalised elderly medical patients with delirium, dementia and comorbid delirium-dementia.

    Science.gov (United States)

    Leonard, Maeve; McInerney, Shane; McFarland, John; Condon, Candice; Awan, Fahad; O'Connor, Margaret; Reynolds, Paul; Meaney, Anna Maria; Adamis, Dimitrios; Dunne, Colum; Cullen, Walter; Trzepacz, Paula T; Meagher, David J

    2016-03-08

    Differentiation of delirium and dementia is a key diagnostic challenge but there has been limited study of features that distinguish these conditions. We examined neuropsychiatric and neuropsychological symptoms in elderly medical inpatients to identify features that distinguish major neurocognitive disorders. University teaching hospital in Ireland. 176 consecutive elderly medical inpatients (mean age 80.6 ± 7.0 years (range 60-96); 85 males (48%)) referred to a psychiatry for later life consultation-liaison service with Diagnostic and Statistical Manual of Mental Disorders (DSM) IV delirium, dementia, comorbid delirium-dementia and cognitively intact controls. Participants were assessed cross-sectionally with comparison of scores (including individual items) for the Revised Delirium Rating Scale (DRS-R98), Cognitive Test for Delirium (CTD) and Neuropsychiatric Inventory (NPI-Q). The frequency of neurocognitive diagnoses was delirium (n=50), dementia (n=32), comorbid delirium-dementia (n=62) and cognitively intact patients (n=32). Both delirium and comorbid delirium-dementia groups scored higher than the dementia group for DRS-R98 and CTD total scores, but all three neurocognitively impaired groups scored similarly in respect of total NPI-Q scores. For individual DRS-R98 items, delirium groups were distinguished from dementia groups by a range of non-cognitive symptoms, but only for impaired attention of the cognitive items. For the CTD, attention (p=0.002) and vigilance (p=0.01) distinguished between delirium and dementia. No individual CTD item distinguished between comorbid delirium-dementia and delirium. For the NPI-Q, there were no differences between the three neurocognitively impaired groups for any individual item severity. The neurocognitive profile of delirium is similar with or without comorbid dementia and differs from dementia without delirium. Simple tests of attention and vigilance can help to distinguish between delirium and other presentations

  14. Integrated Semantics Service Platform for the Internet of Things: A Case Study of a Smart Office

    Science.gov (United States)

    Ryu, Minwoo; Kim, Jaeho; Yun, Jaeseok

    2015-01-01

    The Internet of Things (IoT) allows machines and devices in the world to connect with each other and generate a huge amount of data, which has a great potential to provide useful knowledge across service domains. Combining the context of IoT with semantic technologies, we can build integrated semantic systems to support semantic interoperability. In this paper, we propose an integrated semantic service platform (ISSP) to support ontological models in various IoT-based service domains of a smart city. In particular, we address three main problems for providing integrated semantic services together with IoT systems: semantic discovery, dynamic semantic representation, and semantic data repository for IoT resources. To show the feasibility of the ISSP, we develop a prototype service for a smart office using the ISSP, which can provide a preset, personalized office environment by interpreting user text input via a smartphone. We also discuss a scenario to show how the ISSP-based method would help build a smart city, where services in each service domain can discover and exploit IoT resources that are wanted across domains. We expect that our method could eventually contribute to providing people in a smart city with more integrated, comprehensive services based on semantic interoperability. PMID:25608216

  15. Integrated Semantics Service Platform for the Internet of Things: A Case Study of a Smart Office

    Directory of Open Access Journals (Sweden)

    Minwoo Ryu

    2015-01-01

    Full Text Available The Internet of Things (IoT allows machines and devices in the world to connect with each other and generate a huge amount of data, which has a great potential to provide useful knowledge across service domains. Combining the context of IoT with semantic technologies, we can build integrated semantic systems to support semantic interoperability. In this paper, we propose an integrated semantic service platform (ISSP to support ontological models in various IoT-based service domains of a smart city. In particular, we address three main problems for providing integrated semantic services together with IoT systems: semantic discovery, dynamic semantic representation, and semantic data repository for IoT resources. To show the feasibility of the ISSP, we develop a prototype service for a smart office using the ISSP, which can provide a preset, personalized office environment by interpreting user text input via a smartphone. We also discuss a scenario to show how the ISSP-based method would help build a smart city, where services in each service domain can discover and exploit IoT resources that are wanted across domains. We expect that our method could eventually contribute to providing people in a smart city with more integrated, comprehensive services based on semantic interoperability.

  16. Integrated semantics service platform for the Internet of Things: a case study of a smart office.

    Science.gov (United States)

    Ryu, Minwoo; Kim, Jaeho; Yun, Jaeseok

    2015-01-19

    The Internet of Things (IoT) allows machines and devices in the world to connect with each other and generate a huge amount of data, which has a great potential to provide useful knowledge across service domains. Combining the context of IoT with semantic technologies, we can build integrated semantic systems to support semantic interoperability. In this paper, we propose an integrated semantic service platform (ISSP) to support ontological models in various IoT-based service domains of a smart city. In particular, we address three main problems for providing integrated semantic services together with IoT systems: semantic discovery, dynamic semantic representation, and semantic data repository for IoT resources. To show the feasibility of the ISSP, we develop a prototype service for a smart office using the ISSP, which can provide a preset, personalized office environment by interpreting user text input via a smartphone. We also discuss a scenario to show how the ISSP-based method would help build a smart city, where services in each service domain can discover and exploit IoT resources that are wanted across domains. We expect that our method could eventually contribute to providing people in a smart city with more integrated, comprehensive services based on semantic interoperability.

  17. Interdependence of episodic and semantic memory: Evidence from neuropsychology

    OpenAIRE

    GREENBERG, DANIEL L.; VERFAELLIE, MIEKE

    2010-01-01

    Tulving's (1972) theory of memory draws a distinction between general knowledge (semantic memory) and memory for events (episodic memory). Neuropsychological studies have generally examined each type of memory in isolation, but theorists have long argued that these two forms of memory are interdependent. Here we review several lines of neuropsychological research that have explored the interdependence of episodic and semantic memory. The studies show that these forms of memory can affect each...

  18. Pragmatics for formal semantics

    DEFF Research Database (Denmark)

    Danvy, Olivier

    2011-01-01

    This tech talk describes how to write and how to inter-derive formal semantics for sequential programming languages. The progress reported here is (1) concrete guidelines to write each formal semantics to alleviate their proof obligations, and (2) simple calculational tools to obtain a formal...

  19. A reasonable Semantic Web

    NARCIS (Netherlands)

    Hitzler, Pascal; Van Harmelen, Frank

    2010-01-01

    The realization of Semantic Web reasoning is central to substantiating the Semantic Web vision. However, current mainstream research on this topic faces serious challenges, which forces us to question established lines of research and to rethink the underlying approaches. We argue that reasoning for

  20. Episodic memory, semantic memory, and amnesia.

    Science.gov (United States)

    Squire, L R; Zola, S M

    1998-01-01

    Episodic memory and semantic memory are two types of declarative memory. There have been two principal views about how this distinction might be reflected in the organization of memory functions in the brain. One view, that episodic memory and semantic memory are both dependent on the integrity of medial temporal lobe and midline diencephalic structures, predicts that amnesic patients with medial temporal lobe/diencephalic damage should be proportionately impaired in both episodic and semantic memory. An alternative view is that the capacity for semantic memory is spared, or partially spared, in amnesia relative to episodic memory ability. This article reviews two kinds of relevant data: 1) case studies where amnesia has occurred early in childhood, before much of an individual's semantic knowledge has been acquired, and 2) experimental studies with amnesic patients of fact and event learning, remembering and knowing, and remote memory. The data provide no compelling support for the view that episodic and semantic memory are affected differently in medial temporal lobe/diencephalic amnesia. However, episodic and semantic memory may be dissociable in those amnesic patients who additionally have severe frontal lobe damage.