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Sample records for age perceptual attribute

  1. Perceptual and Social Attributes Underlining Age-Related Preferences for Faces

    Science.gov (United States)

    Kiiski, Hanni S. M.; Cullen, Brendan; Clavin, Sarah L.; Newell, Fiona N.

    2016-01-01

    Although aesthetic preferences are known to be important in person perception and can play a significant role in everyday social decisions, the effect of the age of the observer on aesthetic preferences for faces of different ages has not yet been fully investigated. In the present study we investigated whether aesthetic preferences change with aging, with an age-related bias in favoring faces from one’s own age group. In addition, we examined the role of age on both the perceptual qualities and the social attributes of faces that may influence these aesthetic judgements. Both younger and older adult observers provided ratings to images of younger, middle-aged and older unfamiliar faces. As well as attractiveness, the rating dimensions included other perceptual (distinctiveness, familiarity) and social (competence, trustworthiness and dominance) factors. The results suggested a consistent aesthetic preference for youthful faces across all ages of the observers but, surprisingly, no evidence for an age-related bias in attractiveness ratings. Older adults tended to provide higher ratings of attractiveness, competence and trustworthiness to the unfamiliar faces, consistent with the positivity effect previously reported. We also tested whether perceptual factors such as face familiarity or distinctiveness affected aesthetic ratings. Only ratings of familiarity, but not distinctiveness, were positively associated with the attractiveness of the faces. Moreover, ratings of familiarity decreased with increasing age of the face. With regard to the social characteristics of the faces, we found that the age of the face negatively correlated with ratings of trustworthiness provided by all observers, but with the competence ratings of older observers only. Interestingly, older adults provided higher ratings of perceived competence and trustworthiness to younger than older faces. However, our results also suggest that higher attractiveness ratings, together with older aged

  2. Multiattribute perceptual mapping with idiosyncratic brand and attribute sets

    NARCIS (Netherlands)

    Bijmolt, Tammo H. A.; van de Velden, Michel

    2012-01-01

    This article proposes an extremely flexible procedure for perceptual mapping based on multiattribute ratings, such that the respondent freely generates sets of both brands and attributes. Therefore, the brands and attributes are known and relevant to each participant. Collecting and analyzing such i

  3. Multiattribute perceptual mapping with idiosyncratic brand and attribute sets

    NARCIS (Netherlands)

    T.H.A. Bijmolt (Tammo); M. van de Velden (Michel)

    2012-01-01

    textabstractThis article proposes an extremely flexible procedure for perceptual mapping based on multiattribute ratings, such that the respondent freely generates sets of both brands and attributes. Therefore, the brands and attributes are known and relevant to each participant. Collecting and anal

  4. Multiattribute perceptual mapping with idiosyncratic brand and attribute sets

    OpenAIRE

    Bijmolt, Tammo; Velden, Michel

    2012-01-01

    textabstractThis article proposes an extremely flexible procedure for perceptual mapping based on multiattribute ratings, such that the respondent freely generates sets of both brands and attributes. Therefore, the brands and attributes are known and relevant to each participant. Collecting and analyzing such idiosyncratic datasets can be challenging. Therefore, this study proposes a modification of generalized canonical correlation analysis to support the analysis of the complex data structu...

  5. Memory's aging echo: age-related decline in neural reactivation of perceptual details during recollection.

    Science.gov (United States)

    McDonough, Ian M; Cervantes, Sasha N; Gray, Stephen J; Gallo, David A

    2014-09-01

    Episodic memory decline is a hallmark of normal cognitive aging. Here, we report the first event-related fMRI study to directly investigate age differences in the neural reactivation of qualitatively rich perceptual details during recollection. Younger and older adults studied pictures of complex scenes at different presentation durations along with descriptive verbal labels, and these labels subsequently were used during fMRI scanning to cue picture recollections of varying perceptual detail. As expected from prior behavioral work, the two age groups subjectively rated their recollections as containing similar amounts of perceptual detail, despite objectively measured recollection impairment in older adults. In both age groups, comparisons of retrieval trials that varied in recollected detail revealed robust activity in brain regions previously linked to recollection, including hippocampus and both medial and lateral regions of the prefrontal and posterior parietal cortex. Critically, this analysis also revealed recollection-related activity in visual processing regions that were active in an independent picture-perception task, and these regions showed age-related reductions in activity during recollection that cannot be attributed to age differences in response criteria. These fMRI findings provide new evidence that aging reduces the absolute quantity of perceptual details that are reactivated from memory, and they help to explain why aging reduces the reliability of subjective memory judgments. PMID:24828546

  6. Memory’s Aging Echo: Age-related Decline in Neural Reactivation of Perceptual Details During Recollection

    Science.gov (United States)

    McDonough, Ian M.; Cervantes, Sasha N.; Gray, Stephen J.; Gallo, David A.

    2014-01-01

    Episodic memory decline is a hallmark of normal cognitive aging. Here, we report the first event-related fMRI study to directly investigate age differences in the neural reactivation of qualitatively rich perceptual details during recollection. Younger and older adults studied pictures of complex scenes at different presentation durations along with descriptive verbal labels, and these labels subsequently were used during fMRI scanning to cue picture recollections of varying perceptual detail. As expected from prior behavioral work, the two groups subjectively rated their recollections as containing similar amounts of perceptual detail, despite objectively measured recollection impairment in older adults. In both age groups, comparisons of retrieval trials that varied in recollected detail revealed robust activity in brain regions previously linked to recollection, including hippocampus and both medial and lateral regions of the prefrontal and posterior parietal cortex. Critically, this analysis also revealed recollection-related activity in visual processing regions that were active in an independent picture-perception task, and these regions showed age-related reductions in activity during recollection that cannot be attributed to age differences in response criteria. These fMRI findings provide new evidence that aging reduces the absolute quantity of perceptual details that are reactivated from memory, and they help to explain why aging reduces the reliability of subjective memory judgments. PMID:24828546

  7. Relative Attribute SVM+ Learning for Age Estimation.

    Science.gov (United States)

    Wang, Shengzheng; Tao, Dacheng; Yang, Jie

    2016-03-01

    When estimating age, human experts can provide privileged information that encodes the facial attributes of aging, such as smoothness, face shape, face acne, wrinkles, and bags under-eyes. In automatic age estimation, privileged information is unavailable to test images. To overcome this problem, we hypothesize that asymmetric information can be explored and exploited to improve the generalizability of the trained model. Using the learning using privileged information (LUPI) framework, we tested this hypothesis by carefully defining relative attributes for support vector machine (SVM+) to improve the performance of age estimation. We term this specific setting as relative attribute SVM+ (raSVM+), in which the privileged information enables separation of outliers from inliers at the training stage and effectively manipulates slack variables and age determination errors during model training, and thus guides the trained predictor toward a generalizable solution. Experimentally, the superiority of raSVM+ was confirmed by comparing it with state-of-the-art algorithms on the face and gesture recognition research network (FG-NET) and craniofacial longitudinal morphological face aging databases. raSVM+ is a promising development that improves age estimation, with the mean absolute error reaching 4.07 on FG-NET. PMID:25850101

  8. Age effects on visual-perceptual processing and confrontation naming.

    Science.gov (United States)

    Gutherie, Audrey H; Seely, Peter W; Beacham, Lauren A; Schuchard, Ronald A; De l'Aune, William A; Moore, Anna Bacon

    2010-03-01

    The impact of age-related changes in visual-perceptual processing on naming ability has not been reported. The present study investigated the effects of 6 levels of spatial frequency and 6 levels of contrast on accuracy and latency to name objects in 14 young and 13 older neurologically normal adults with intact lexical-semantic functioning. Spatial frequency and contrast manipulations were made independently. Consistent with the hypotheses, variations in these two visual parameters impact naming ability in young and older subjects differently. The results from the spatial frequency-manipulations revealed that, in general, young vs. older subjects are faster and more accurate to name. However, this age-related difference is dependent on the spatial frequency on the image; differences were only seen for images presented at low (e.g., 0.25-1 c/deg) or high (e.g., 8-16 c/deg) spatial frequencies. Contrary to predictions, the results from the contrast manipulations revealed that overall older vs. young adults are more accurate to name. Again, however, differences were only seen for images presented at the lower levels of contrast (i.e., 1.25%). Both age groups had shorter latencies on the second exposure of the contrast-manipulated images, but this possible advantage of exposure was not seen for spatial frequency. Category analyses conducted on the data from this study indicate that older vs. young adults exhibit a stronger nonliving-object advantage for naming spatial frequency-manipulated images. Moreover, the findings suggest that bottom-up visual-perceptual variables integrate with top-down category information in different ways. Potential implications on the aging and naming (and recognition) literature are discussed. PMID:19670050

  9. Perceptual Accent Rating and Attribution in Psychogenic FAS: Some Further Evidence Challenging Whitaker's Operational Definition.

    Science.gov (United States)

    Keulen, Stefanie; Verhoeven, Jo; Bastiaanse, Roelien; Mariën, Peter; Jonkers, Roel; Mavroudakis, Nicolas; Paquier, Philippe

    2016-01-01

    A 40-year-old, non-aphasic, right-handed, and polyglot (L1: French, L2: Dutch, and L3: English) woman with a 12-year history of addiction to opiates and psychoactive substances, and clear psychiatric problems, presented with a foreign accent of sudden onset in L1. Speech evolved toward a mostly fluent output, despite a stutter-like behavior and a marked grammatical output disorder. The psychogenic etiology of the accent foreignness was construed based on the patient's complex medical history and psychodiagnostic, neuropsychological, and neurolinguistic assessments. The presence of a foreign accent was affirmed by a perceptual accent rating and attribution experiment. It is argued that this patient provides additional evidence demonstrating the outdatedness of Whitaker's (1982) definition of foreign accent syndrome, as only one of the four operational criteria was unequivocally applicable to our patient: her accent foreignness was not only recognized by her relatives and the medical staff but also by a group of native French-speaking laymen. However, our patient defied the three remaining criteria, as central nervous system damage could not conclusively be demonstrated, psychodiagnostic assessment raised the hypothesis of a conversion disorder, and the patient was a polyglot whose newly gained accent was associated with a range of foreign languages, which exceeded the ones she spoke. PMID:26973488

  10. The Effects of Age and Expertise upon Perceptual Skill Development in a Racquet Sport.

    Science.gov (United States)

    Abernethy, Bruce

    1988-01-01

    Data from this study of skilled and unskilled badminton players aged 10 to adult indicated the presence of systematic differences which transcend developmental age between the perceptual skills of expert and novice players. (JD)

  11. Detecting age differences in inhibition processes with a test of perceptual and motor inhibition

    OpenAIRE

    Jennings, J. Richard; Mendelson, David N.; Redfern, Mark S.; Nebes, Robert D.

    2011-01-01

    We asked whether different forms of inhibition are altered differently by aging using a Motor and Perceptual Inhibition Test (MAPIT) based on Nassauer and Halperin (Nassauer & Halperin, 2003). Ninety-eight individuals participating in studies of balance and attention were separated into younger (mean age 25 years) and older participants (mean age 73). Older participants showed less Perceptual and Motor Inhibition than younger participant with moderation of this effect by gender. The two score...

  12. ATTRIBUTE BASED PERCEPTUAL MAPPING USING DISCRIMINANT ANALYSIS REGARDING SELECTED BRANDS OF MOBILE HANDSETS: AN EMPIRICAL INVESTIGATION IN HARYANA

    Directory of Open Access Journals (Sweden)

    Dr. Ashutosh Nigam

    2012-09-01

    Full Text Available Indian mobile handset industry has seen explosive growth backed by liberalization and heavy investment in the telecommunication infrastructure. With growth it becomes extremely important for mobile handset brands to position their brands properly. This paperattempts to know how customers perceive different brands of mobile handset in the light of attributes considered by consumers in making purchase decision. A questionnaire survey of 300 respondents was collected in Haryana. Discriminant analysis is used to draw perceptual maps showing selected mobile handset companies. The results showed that selected mobile handset brands do not differsignificantly with regard to given attributes.

  13. Differential Effects of Intelligence, Perceptual Speed and Age on Growth in Attentional Speed and Accuracy

    Science.gov (United States)

    Goldhammer, Frank; Rauch, Wolfgang A.; Schweizer, Karl; Moosbrugger, Helfried

    2010-01-01

    The study investigates the effects of intelligence, perceptual speed and age on intraindividual growth in attentional speed and attentional accuracy over the course of a 6-minute testing session. A sample of 193 subjects completed the Advanced Progressive Matrices and the Vienna Matrices Test representing intelligence, the tests Alertness and…

  14. Reduction in the retinotopic early visual cortex with normal aging and magnitude of perceptual learning

    Science.gov (United States)

    Chang, Li-Hung; Yotsumoto, Yuko; Salat, David H.; Andersen, George J.; Watanabe, Takeo; Sasaki, Yuka

    2014-01-01

    While normal aging is known to reduce cortical structures globally, the effects of aging on local structures and functions of early visual cortex are less understood. Here, using standard retinotopic mapping and magnetic resonance imaging (MRI) morphological analyses, we investigated whether aging affects areal size of the early visual cortex, which were retinotopically localized, and whether those morphological measures were associated with individual performance on visual perceptual learning. First, significant age-associated reduction was found in the areal size of V1, V2, and V3. Second, individual ability of visual perceptual learning was significantly correlated with areal size of V3 in older adults. These results demonstrate that aging changes local structures of the early visual cortex and the degree of change may be associated with individual visual plasticity. PMID:25277041

  15. Perceptual attributes of poultry and other meat products: a repertory grid application.

    Science.gov (United States)

    Michel, L Martínez; Punter, P H; Wismer, W V

    2011-04-01

    Increased demand for processed poultry products through the growth of home meal replacements and ready to eat products, present an opportunity for the development of new value-added poultry products. Repertory grid interviews were conducted to generate insight into consumer driven product development of these products. Procrustes analysis revealed that healthiness, nutrition, convenience, and processing attributes were most important parameters for discriminating amongst 24 meat and meat alternatives. "White meat", "healthier", "leaner", "good source of protein", "easy to cook" and "convenient", were found to positively influence consumer preferences for unprocessed chicken products, eggs and salmon while price did not appear to be important for differentiating the products. Traditional processed fish and poultry products, such as chicken nuggets, represented undesirable composition, processing and quality concerns. Identification of consumer attributes for discriminating poultry products among other meat alternatives can guide the development of competitive value-added poultry products. PMID:21146327

  16. Perceptual discrimination across contexts and contrasts in preschool-aged children

    Science.gov (United States)

    BYUN, Tara McALLISTER

    2015-01-01

    This paper investigates a proposed phonetically-based account of developmental phonological patterns that lack counterparts in adult typology. Adult listeners perceive some phonemic contrasts more accurately than others, and these differences in perceptual recoverability are posited to represent one influence on phonological typology. One hypothesis suggests that children and adults could differ in their patterns of relative perceptual sensitivity, and these differences could form the basis for some child-specific phonological patterns in production. However, there has been a lack of empirical evidence to support this claim. This study used a nonword discrimination task to investigate differences in perceptual recoverability across contrasts and contexts in typically-developing preschool children. Participants heard nonwords that were identical or differed by a single segment in initial or final position. Results revealed general agreement between child and adult listeners in the relative discriminability of different featural contrasts. For certain contrasts, discrimination accuracy was significantly greater in initial than final position, mirroring an asymmetry seen in adults. Overall, these results suggest that perceptual discrimination in preschool-aged children is broadly congruent with patterns of relative sensitivity observed in adult listeners. These findings suggest that factors other than perceptual recoverability should be explored to account for child-specific phonological patterns. PMID:26213418

  17. Age-related effects on perceptual and semantic encoding in memory.

    Science.gov (United States)

    Kuo, M C C; Liu, K P Y; Ting, K H; Chan, C C H

    2014-03-01

    This study examined the age-related subsequent memory effect (SME) in perceptual and semantic encoding using event-related potentials (ERPs). Seventeen younger adults and 17 older adults studied a series of Chinese characters either perceptually (by inspecting orthographic components) or semantically (by determining whether the depicted object makes sounds). The two tasks had similar levels of difficulty. The participants made studied or unstudied judgments during the recognition phase. Younger adults performed better in both conditions, with significant SMEs detected in the time windows of P2, N3, P550, and late positive component (LPC). In the older group, SMEs were observed in the P2 and N3 latencies in both conditions but were only detected in the P550 in the semantic condition. Between-group analyses showed larger frontal and central SMEs in the younger sample in the LPC latency regardless of encoding type. Aging effect appears to be stronger on influencing perceptual than semantic encoding processes. The effects seem to be associated with a decline in updating and maintaining representations during perceptual encoding. The age-related decline in the encoding function may be due in part to changes in frontal lobe function. PMID:24374080

  18. Perceptual restoration of degraded speech is preserved with advancing age.

    Science.gov (United States)

    Saija, Jefta D; Akyürek, Elkan G; Andringa, Tjeerd C; Başkent, Deniz

    2014-02-01

    Cognitive skills, such as processing speed, memory functioning, and the ability to divide attention, are known to diminish with aging. The present study shows that, despite these changes, older adults can successfully compensate for degradations in speech perception. Critically, the older participants of this study were not pre-selected for high performance on cognitive tasks, but only screened for normal hearing. We measured the compensation for speech degradation using phonemic restoration, where intelligibility of degraded speech is enhanced using top-down repair mechanisms. Linguistic knowledge, Gestalt principles of perception, and expectations based on situational and linguistic context are used to effectively fill in the inaudible masked speech portions. A positive compensation effect was previously observed only with young normal hearing people, but not with older hearing-impaired populations, leaving the question whether the lack of compensation was due to aging or due to age-related hearing problems. Older participants in the present study showed poorer intelligibility of degraded speech than the younger group, as expected from previous reports of aging effects. However, in conditions that induce top-down restoration, a robust compensation was observed. Speech perception by the older group was enhanced, and the enhancement effect was similar to that observed with the younger group. This effect was even stronger with slowed-down speech, which gives more time for cognitive processing. Based on previous research, the likely explanations for these observations are that older adults can overcome age-related cognitive deterioration by relying on linguistic skills and vocabulary that they have accumulated over their lifetime. Alternatively, or simultaneously, they may use different cerebral activation patterns or exert more mental effort. This positive finding on top-down restoration skills by the older individuals suggests that new cognitive training methods

  19. Perceptual Accent Rating and Attribution in Psychogenic FAS: Some Further Evidence Challenging Whitaker’s Operational Definition

    Science.gov (United States)

    Keulen, Stefanie; Verhoeven, Jo; Bastiaanse, Roelien; Mariën, Peter; Jonkers, Roel; Mavroudakis, Nicolas; Paquier, Philippe

    2016-01-01

    A 40-year-old, non-aphasic, right-handed, and polyglot (L1: French, L2: Dutch, and L3: English) woman with a 12-year history of addiction to opiates and psychoactive substances, and clear psychiatric problems, presented with a foreign accent of sudden onset in L1. Speech evolved toward a mostly fluent output, despite a stutter-like behavior and a marked grammatical output disorder. The psychogenic etiology of the accent foreignness was construed based on the patient’s complex medical history and psychodiagnostic, neuropsychological, and neurolinguistic assessments. The presence of a foreign accent was affirmed by a perceptual accent rating and attribution experiment. It is argued that this patient provides additional evidence demonstrating the outdatedness of Whitaker’s (1982) definition of foreign accent syndrome, as only one of the four operational criteria was unequivocally applicable to our patient: her accent foreignness was not only recognized by her relatives and the medical staff but also by a group of native French-speaking laymen. However, our patient defied the three remaining criteria, as central nervous system damage could not conclusively be demonstrated, psychodiagnostic assessment raised the hypothesis of a conversion disorder, and the patient was a polyglot whose newly gained accent was associated with a range of foreign languages, which exceeded the ones she spoke. PMID:26973488

  20. Perceptual accent rating and attribution in psychogenic FAS: some further evidence challenging Whitaker’s operational definition.

    Directory of Open Access Journals (Sweden)

    Stefanie eKeulen

    2016-03-01

    Full Text Available A 40-year-old, non-aphasic, right-handed, and polyglot (L1: French, L2: Dutch, L3: English woman with a 12 year history of addiction to opiates and psychoactive substances, and clear psychiatric problems, presented with a foreign accent of sudden onset in L1. Speech evolved towards a mostly fluent output, despite a stutter-like behavior and a marked grammatical output disorder. The psychogenic etiology of the accent foreignness was construed based upon the patient’s complex medical history, and psychodiagnostic, neuropsychological, and neurolinguistic assessments. The presence of a foreign accent was affirmed by a perceptual accent rating and attribution experiment. It is argued that this patient provides additional evidence demonstrating the outdatedness of Whitaker’s (1982 definition of Foreign Accent Syndrome, as only one of the four operational criteria was unequivocally applicable to our patient: her accent foreignness was not only recognized by her relatives and the medical staff, but also by a group of native French-speaking laymen. However, our patient defied the three remaining criteria, as central nervous system damage could not conclusively be demonstrated, psychodiagnostic assessment raised the hypothesis of a conversion disorder, and the patient was a polyglot whose newly gained accent was associated with a range of foreign languages, which exceeded the ones she spoke.

  1. I can see clearly now: The effects of age and perceptual load on inattentional blindness

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    Anna Remington

    2014-04-01

    Full Text Available Attention and awareness are known to be linked (e.g. see Lavie, Beck, & Konstantinou, 2014, for a review. However the extent to which this link changes over development is not fully understood. Most research concerning the development of attention has investigated the effects of attention on distraction, visual search and spatial orienting, typically using reaction time measures which cannot directly support conclusions about conscious awareness. Here we used Lavie’s Load Theory of Attention and Cognitive Control to examine the development of attention effects on awareness. According to Load Theory awareness levels are determined by the availability of attentional capacity. We hypothesised that attentional capacity develops with age, and consequently that awareness rates should increase with development due to the enhanced capacity. Thus we predicted that greater rates of inattentional blindness (IB would be found at a younger age, and that lower levels of perceptual load will be sufficient to exhaust capacity and cause IB in children but not adults. We tested this hypothesis using an IB paradigm with adults and children aged 7-8, 9-10, 11-12 and 13 years old. Participants performed a line-length judgment task (indicating which arm of a cross is longer and on the last trial were asked to report whether they noticed an unexpected task-irrelevant stimulus (a small square in the display. Perceptual load was varied by changing the line-length difference (with a smaller difference in the conditions of higher load. The results supported our hypothesis: levels of awareness increased with age, and a moderate increase in the perceptual load of the task led to greater IB for children but not adults. These results extended across both peripheral and central presentations of the task stimuli. Overall, these findings establish the development of capacity for awareness and demonstrate the critical role of the perceptual load in the attended task.

  2. Age-related face processing bias in infancy: evidence of perceptual narrowing for adult faces.

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    Macchi Cassia, Viola; Bulf, Hermann; Quadrelli, Ermanno; Proietti, Valentina

    2014-02-01

    Recent data demonstrate a perceptual processing advantage for adult faces in both adults and young children, suggesting that face representation is shaped by visual experience accumulated with different face-age groups. As for species and race, this age bias may emerge during the first year of life as part of the general process of perceptual narrowing, given the extensive amount of social and perceptual experience accumulated with caregivers and/or other adult individuals. Using infant-controlled habituation and visual-paired comparison at test, two experiments were carried out to examine 3- and 9-month-olds' ability to discriminate within adult and infant faces. Results showed that, when they are provided with adequate time to visually compare the stimuli during test trials (Experiment 2), 3-month-olds exhibit above-chance discrimination of adult and infant faces. Instead, 9-month-olds discriminate adult faces but not infant faces (Experiments 1 and 2). Results provide the first evidence of age-related face processing biases in infancy, and show that by 9 months face representations tune to adult human faces. PMID:24374735

  3. Aging into perceptual control: A Dynamic Causal Modeling for fMRI study of bistable perception

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    Ehsan eDowlati

    2016-03-01

    Full Text Available Aging is accompanied by stereotyped changes in functional brain activations, for example a cortical shift in activity patterns from posterior to anterior regions is one hallmark revealed by functional magnetic resonance imaging (fMRI of aging cognition. Whether these neuronal effects of aging could potentially contribute to an amelioration of or resistance to the cognitive symptoms associated with psychopathology remains to be explored. We used a visual illusion paradigm to address whether aging affects the cortical control of perceptual beliefs and biases. Our aim was to understand the effective connectivity associated with volitional control of ambiguous visual stimuli and to test whether greater top-down control of early visual networks emerged with advancing age. Using a bias training paradigm for ambiguous images we found that older participants (n = 16 resisted experimenter-induced visual bias compared to a younger cohort (n = 14 and that this resistance was associated with greater activity in prefrontal and temporal cortices. By applying Dynamic Causal Models for fMRI we uncovered a selective recruitment of top-down connections from the middle temporal to lingual gyrus by the older cohort during the perceptual switch decision following bias training. In contrast, our younger cohort did not exhibit any consistent connectivity effects but instead showed a loss of driving inputs to orbitofrontal sources following training. These findings suggest that perceptual beliefs are more readily controlled by top-down strategies in older adults and introduce age-dependent neural mechanisms that may be important for understanding aberrant belief states associated with psychopathology.

  4. Well-Being Affects Changes in Perceptual Speed in Advanced Old Age: Longitudinal Evidence for a Dynamic Link

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    Gerstorf, Denis; Lovden, Martin; Rocke, Christina; Smith, Jacqui; Lindenberger, Ulman

    2007-01-01

    This study examined competing hypotheses about dynamic cross-domain associations between perceptual speed and well-being in advanced old age. We applied the bivariate dual change score model (J. J. McArdle & F. Hamagami, 2001) to 13-year incomplete longitudinal data from the Berlin Aging Study (P. B. Baltes & K. U. Mayer, 1999; N = 516, 70-103…

  5. Normative perceptual estimates for 91 healthy subjects age 60–75: impact of age, education, employment, physical exercise, alcohol, and video gaming

    OpenAIRE

    Wilms, Inge L.; Nielsen, Simon

    2014-01-01

    Visual perception serves as the basis for much of the higher level cognitive processing as well as human activity in general. Here we present normative estimates for the following components of visual perception: the visual perceptual threshold, the visual short-term memory (VSTM) capacity and the visual perceptual encoding/decoding speed (processing speed) of VSTM based on an assessment of 91 healthy subjects aged 60–75. The estimates were modeled from input from a whole-report assessment ba...

  6. Perceptual learning and Aging: Improved performance for low contrast motion discrimination

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    GeorgeJAndersen

    2013-02-01

    Full Text Available Previous research has shown age related differences in discriminating motion at different levels of contrast (Betts, Sekuler, & Bennett, 2009; 2012; Betts, Taylor, Sekuler & Bennett, 2005. A surprising result of this research is that older as compared to younger observers showed improved performance in detecting motion of large high contrast stimuli suggesting age-related differences in center-surround antagonism. In the present study we examined whether perceptual learning methods could be used to improve motion discrimination performance for older individuals under high- and low-contrast conditions. The stimuli were centrally presented Gaussian filtered sine-wave gratings (Gabors that were either 5 or 0.7 degree diameter with contrast of 0.92, 0.22, or 0.028. Older and younger participants received 3 days of training. The task was to identify if the motion direction was leftward or rightward. Duration thresholds for motion discrimination were derived using two randomly interleaved staircases and compared between pre-/post- test sessions. Both older and younger subjects showed lower duration thresholds as a result of training. The improved performance, for older subjects, due to training was observed for all size and contrast conditions, with training with small low-contrast stimuli resulting in a 23% improvement in motion discrimination performance. Older observers, as compared to younger observers, did show evidence of decreased spatial suppression across all contrast levels. These results suggest that perceptual learning techniques are effective for improving motion discrimination performance, especially for conditions that are difficult for older individuals.

  7. False Memory in Ageing: Comparing False Recognition to Semantically and Perceptually Similar Words

    OpenAIRE

    Mackay, Sophie

    2012-01-01

    Older adults are more susceptible to gist-based false memories. According to Koutstaal et als’ (2003) semantic categorisation account this is because, in situations where both semantic and perceptual information is present i.e. conceptually related picture recognition, older adults tend to focus on the semantic information at the expense of the perceptual. It was unclear, however, whether this would apply to a situation, such as word lists, where the processing of precise perceptual informati...

  8. Auditory perceptual learning in adults with and without age-related hearing loss

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    Hanin eKarawani

    2016-02-01

    Full Text Available Introduction: Speech recognition in adverse listening conditions becomes more difficult as we age, particularly for individuals with age-related hearing loss (ARHL. Whether these difficulties can be eased with training remains debated, because it is not clear whether the outcomes are sufficiently general to be of use outside of the training context. The aim of the current study was to compare training-induced learning and generalization between normal-hearing older adults and those with ARHL.Methods: 56 listeners (60-72 y/o, 35 participants with ARHL and 21 normal hearing adults participated in the study. The study design was a cross over design with three groups (immediate-training, delayed-training and no-training group. Trained participants received 13 sessions of home-based auditory training over the course of 4 weeks. Three adverse listening conditions were targeted: (1 Speech-in-noise (2 time compressed speech and (3 competing speakers, and the outcomes of training were compared between normal and ARHL groups. Pre- and post-test sessions were completed by all participants. Outcome measures included tests on all of the trained conditions as well as on a series of untrained conditions designed to assess the transfer of learning to other speech and non-speech conditions. Results: Significant improvements on all trained conditions were observed in both ARHL and normal-hearing groups over the course of training. Normal hearing participants learned more than participants with ARHL in the speech-in-noise condition, but showed similar patterns of learning in the other conditions. Greater pre- to post-test changes were observed in trained than in untrained listeners on all trained conditions. In addition, the ability of trained listeners from the ARHL group to discriminate minimally different pseudowords in noise also improved with training. Conclusions: ARHL did not preclude auditory perceptual learning but there was little generalization to

  9. More Attention to Attention? An Eye-Tracking Investigation of Selection of Perceptual Attributes during a Task Switch

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    Longman, Cai S.; Lavric, Aureliu; Monsell, Stephen

    2013-01-01

    Switching tasks prolongs response times, an effect reduced but not eliminated by active preparation. To explore the role of attentional selection of the relevant stimulus attribute in these task-switch costs, we measured eye fixations in participants cued to identify either a face or a letter displayed on its forehead. With only 200 ms between cue…

  10. Atypical perceptual narrowing in prematurely born infants is associated with compromised language acquisition at 2 years of age

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    Suominen Kalervo

    2010-07-01

    Full Text Available Abstract Background Early auditory experiences are a prerequisite for speech and language acquisition. In healthy children, phoneme discrimination abilities improve for native and degrade for unfamiliar, socially irrelevant phoneme contrasts between 6 and 12 months of age as the brain tunes itself to, and specializes in the native spoken language. This process is known as perceptual narrowing, and has been found to predict normal native language acquisition. Prematurely born infants are known to be at an elevated risk for later language problems, but it remains unclear whether these problems relate to early perceptual narrowing. To address this question, we investigated early neurophysiological phoneme discrimination abilities and later language skills in prematurely born infants and in healthy, full-term infants. Results Our follow-up study shows for the first time that perceptual narrowing for non-native phoneme contrasts found in the healthy controls at 12 months was not observed in very prematurely born infants. An electric mismatch response of the brain indicated that whereas full-term infants gradually lost their ability to discriminate non-native phonemes from 6 to 12 months of age, prematurely born infants kept on this ability. Language performance tested at the age of 2 years showed a significant delay in the prematurely born group. Moreover, those infants who did not become specialized in native phonemes at the age of one year, performed worse in the communicative language test (MacArthur Communicative Development Inventories at the age of two years. Thus, decline in sensitivity to non-native phonemes served as a predictor for further language development. Conclusion Our data suggest that detrimental effects of prematurity on language skills are based on the low degree of specialization to native language early in development. Moreover, delayed or atypical perceptual narrowing was associated with slower language acquisition. The

  11. Normative perceptual estimates for 91 healthy subjects age 60-75: impact of age, education, employment, physical exercise, alcohol, and video gaming.

    Science.gov (United States)

    Wilms, Inge L; Nielsen, Simon

    2014-01-01

    Visual perception serves as the basis for much of the higher level cognitive processing as well as human activity in general. Here we present normative estimates for the following components of visual perception: the visual perceptual threshold, the visual short-term memory (VSTM) capacity and the visual perceptual encoding/decoding speed (processing speed) of VSTM based on an assessment of 91 healthy subjects aged 60-75. The estimates were modeled from input from a whole-report assessment based on a theory of visual attention. In addition to the estimates themselves, we present correlational data, and multiple regression analyses between the estimates and self-reported demographic data and lifestyle variables. The regression statistics suggest that education level, video gaming activity, and employment status may significantly impact the encoding/decoding speed of VTSM but not the capacity of VSTM nor the visual perceptual threshold. The estimates will be useful for future studies into the effects of various types of intervention and training on cognition in general and visual attention in particular. PMID:25339932

  12. Neuroanatomical and cognitive correlates of adult age differences in acquisition of a perceptual-motor skill.

    Science.gov (United States)

    Raz, N; Williamson, A; Gunning-Dixon, F; Head, D; Acker, J D

    2000-10-01

    The objective of this study was to examine age differences in procedural learning and performance in conjunction with differential aging of central nervous system (CNS) structures. Sixty-eight healthy volunteers (age 22-80) performed a pursuit rotor task (four blocks of 20 15-second trials each). Volumes of the cerebellar hemispheres, neostriatum, prefrontal cortex, and hippocampus were measured from Magnetic Resonance (MR) images. Improvement in pursuit rotor performance was indexed by increase in time on target (TOT). A general improvement trend was evident across the blocks of trials. Overall, younger participants showed significantly longer TOT. The rate of improvement was age-invariant during the initial stages of skill acquisition but became greater in middle-aged participants as the practice progressed. When the influences of regional brain volumes were taken into account, the direct age effect on mean TOT measured during the first day of practice disappeared. Instead, reduced volumes of the cerebellar hemispheres and the putamen and poorer performance on nonverbal working memory tasks predicted shorter TOT. In contrast, neither the volume of the caudate and the hippocampus, nor verbal working memory showed association with motor performance. Pursuit rotor performance at the later stages of practice was unrelated to the reduction in putamen volume and was affected directly by age, cerebellar volume, and nonverbal working memory proficiency. We conclude that in a healthy population showing no clinical signs of extrapyramidal disease, age-related declines in procedural learning are associated with reduced volume of the cerebellar hemispheres and lower nonverbal working memory scores. During initial stages of skill acquisition, reduced volume of the putamen is also predictive of poorer performance. PMID:11002356

  13. Influence of dose and age of radiation exposure on attributable risk in mice

    International Nuclear Information System (INIS)

    The present study was aimed to clarify influence of the dose and age of radiation exposure on attributable risk, relative cumulative hazard and expression pattern of the lethal diseases. The attributable risk, relative cumulative hazard and excess cumulative hazard were estimated with the age-specific mortalities. Experimental data using female B6C3F1 mice were made subject of analysis. In this experiment mice were irradiated at day 14, 17 or 18 prenatal age or day 0, 7, 35, 105, 240 or 365 postnatal age with doses ranging from 0.95 to 5.7 Gy of 137Cs γ-rays and were allowed to live out their entire life spans under a specific pathogen free condition. Among mice irradiated at day 0 postnatal period the attributable risk and relative cumulative hazard were 38 % and 1.61, respectively; whereas, shortening of the mean life span was 7 %. Shape of dose-response relationship for the attributable risk was downward concave and that for the relative cumulative hazard was upward concave. The relative cumulative hazards in mice irradiated during neonatal or juvenile period were apparently higher than that irradiated during adulthood. Latent period for expression of radiation-induced lethal diseases in mice irradiated during the prenatal or early postnatal period was longer than that in mice exposed during adult period. Susceptibility of mice in the late fetal period to induction of late-occurring lethal diseases was lower than neonatal mice and was almost similar to young adult mice. The relative cumulative hazard did not increase with statistically significant difference when mice were irradiated at day 14 prenatal age with 0.95 Gy. (author)

  14. Application of Text Mining to Extract Hotel Attributes and Construct Perceptual Map of Five Star Hotels from Online Review: Study of Jakarta and Singapore Five-Star Hotels

    Directory of Open Access Journals (Sweden)

    Arga Hananto

    2015-12-01

    Full Text Available The use of post-purchase online consumer review in hotel attributes study was still scarce in the literature. Arguably, post purchase online review data would gain more accurate attributes thatconsumers actually consider in their purchase decision. This study aims to extract attributes from two samples of five-star hotel reviews (Jakarta and Singapore with text mining methodology. In addition,this study also aims to describe positioning of five-star hotels in Jakarta and Singapore based on the extracted attributes using Correspondence Analysis. This study finds that reviewers of five star hotels in both cities mentioned similar attributes such as service, staff, club, location, pool and food. Attributes derived from text mining seem to be viable input to build fairly accurate positioning map of hotels. This study has demonstrated the viability of online review as a source of data for hotel attribute and positioning studies.

  15. Normative perceptual estimates for 91 healthy subjects age 60-75

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; Nielsen, Simon

    2014-01-01

    of Visual Attention (TVA). In addition to the estimates themselves, we present correlational data on between the estimates and self-reported demographic data and activities of daily living. The correlates suggests that age, video gaming activity and employment status may significantly impact the encoding...

  16. Application of Text Mining to Extract Hotel Attributes and Construct Perceptual Map of Five Star Hotels from Online Review: Study of Jakarta and Singapore Five-Star Hotels

    OpenAIRE

    Arga Hananto

    2015-01-01

    The use of post-purchase online consumer review in hotel attributes study was still scarce in the literature. Arguably, post purchase online review data would gain more accurate attributes thatconsumers actually consider in their purchase decision. This study aims to extract attributes from two samples of five-star hotel reviews (Jakarta and Singapore) with text mining methodology. In addition,this study also aims to describe positioning of five-star hotels in Jakarta and Singapore based on t...

  17. Event-related potentials dissociate perceptual from response-related age effects in visual search

    DEFF Research Database (Denmark)

    Wiegand, Iris; Müller, Hermann J.; Finke, Kathrin;

    2013-01-01

    measures with lateralized event-related potentials of younger and older adults performing a compound-search task, in which the target-defining dimension of a pop-out target (color/shape) and the response-critical target feature (vertical/horizontal stripes) varied independently across trials. Slower...... responses in older participants were associated with age differences in all analyzed event-related potentials from perception to response, indicating that behavioral slowing originates from multiple stages within the information-processing stream. Furthermore, analyses of carry-over effects from one trial...

  18. Mortality Attributable to Obesity among Middle-Aged Adults in the United States

    OpenAIRE

    Mehta, Neil K; Chang, Virginia W.

    2009-01-01

    Obesity is considered a major cause of premature mortality and a potential threat to the longstanding secular decline in mortality in the United States. We measure relative and attributable risks associated with obesity among middle-aged adults using data from the Health and Retirement Study (1992–2004). Although class II/III obesity (BMI ≥ 35.0 kg/m2) increases mortality by 40% in females and 62% in males compared with normal BMI (BMI = 18.5–24.9), class I obesity (BMI = 30.0–34.9) and being...

  19. Dynamic perceptual mapping

    OpenAIRE

    Greenacre, Michael

    2009-01-01

    Perceptual maps have been used for decades by market researchers to illuminate them about the similarity between brands in terms of a set of attributes, to position consumers relative to brands in terms of their preferences, or to study how demographic and psychometric variables relate to consumer choice. Invariably these maps are two-dimensional and static. As we enter the era of electronic publishing, the possibilities for dynamic graphics are opening up. We demonstrate the u...

  20. Phase shift in leaf movements of xanthium attributed to age and rhythm patterns.

    Science.gov (United States)

    Koukkari, W L; Hobbs, L C; Salisbury, F B

    1992-04-01

    Leaves of cockelbur (Xanthium strumarium L.) have been reported to be in either an upright or downward position during the dark span (night) of a 24-hour cycle. Results from our studies clearly indicate that such differences in leaf position are not related to differences in ecotypes but can be attributed to age of the leaf, pattern of the waveform of the rhythm at various stages of the light-dark synchronizer regimen, and the statistical model used for the analysis of the waveform. Younger leaves reached a maximum upright position closer to the middle of the dark span, whereas older leaves reached this position closer to the end of the dark span. A phase shift of up to 6 to 10 hours may occur as the leaf ages. Results from the examination of the pattern of the waveform at four different times showed that the pattern of a younger leaf was different from that of an older leaf during the middle of the dark span, during the light-to-dark transition, and during the middle of the light span, but not during the dark-to-light transition. Linear regression, statistical analyses, and the fitting of harmonics clearly indicate that it is the trough, more than the peak, that differs with the age of the leaf. PMID:16668803

  1. MECHANISMS OF PERCEPTUAL LEARNING

    OpenAIRE

    Lu, Zhong-Lin; Dosher, Barbara Anne

    2009-01-01

    What is learned in perceptual learning? How does perceptual learning change the perceptual system? We investigate these questions using a systems analysis of the perceptual system during the course of perceptual learning using psychophysical methods and models of the observer. Effects of perceptual learning on an observer’s performance are characterized by external noise tests within the framework of noisy observer models. We find evidence that two independent mechanisms, external noise exclu...

  2. Visual Perceptual Learning

    OpenAIRE

    Lu, Zhong-Lin; Hua, Tianmiao; Huang, Chang-Bing; Zhou, Yifeng; Dosher, Barbara Anne

    2010-01-01

    Perceptual learning refers to the phenomenon that practice or training in perceptual tasks often substantially improves perceptual performance. Often exhibiting stimulus or task specificities, perceptual learning differs from learning in the cognitive or motor domains. Research on perceptual learning reveals important plasticity in adult perceptual systems, and as well as the limitations in the information processing of the human observer. In this article, we review the behavioral results, me...

  3. Personality Attributes of Malaysian Youth: Age Differences in Big Five Domains From 15 To 39

    OpenAIRE

    2012-01-01

    The present study investigated age and gender differences in Big Five in a Malay speaking Malaysian youth (N=1036). Participants ranging in age from 15 to 39 years completed Big Five Inventory (BFI). Age differences were found suggesting that mean levels of Neuroticism are negatively associated with age, whereas Agreeableness, Conscientiousness and Extraversion are positively associated. Openness to experience demonstrated a curvilinear associated with age with highest mean levels in middle a...

  4. Risks of alcohol-attributable hospitalisation and death in Australia over time: Evidence of divergence by region, age and sex.

    Directory of Open Access Journals (Sweden)

    Richard Pascal

    2013-03-01

    Full Text Available BackgroundPast reports on trends of alcohol consumption and related harm have generally been descriptive in nature and have not provided evidence of whether changes over time are significant.AimsWe investigated whether: (i the risk of alcohol-attributable hospitalisation and death between 1994 and 2005 for three different age groups changed significantly across all Australian jurisdictions; and (ii the relative rates of hospitalisation for males and females changed over time.MethodEstimates of alcohol-attributable hospitalisations and deaths were calculated using the aetiologic fraction method. Hospitalisations and deaths were grouped by age: 15-29 years, 30-44 years and 45+ years. Risk estimates and risk differences were analysed using Poisson regression.ResultsRisk of alcohol-attributable hospital separations increased nationally and across most jurisdictions throughout the study period. Male and female rates converged over time. Alcohol-attributable deaths decreased nationally across the three age groups and across several jurisdictions beginning in the mid-1990s.ConclusionNationally, alcohol-attributable deaths declined while hospitalisations rose. However, states with higher population density tended to drive national rates, with considerable variation by jurisdiction. The conditions which dominated hospitalisations (e.g. alcohol dependence, falls differed substantially from those underlying alcoholattributable deaths (e.g. alcoholic liver cirrhosis, road crashes. Jurisdictional variation in death and hospitalisations rates as well as changes over time may be partly due to differences in: regulation of alcohol supply; patterns and levels of alcohol consumption; the nature and effectiveness of law enforcement; demographic characteristics of general and sub-populations; and medical health services and screening for chronic conditions.

  5. Measures of Job Perceptions: Gender and Age of Current Incumbents, Suitability, and Job Attributes.

    Science.gov (United States)

    Macan, Therese Hoff; And Others

    1994-01-01

    Compares two ways of examining the gender and age stereotypes of jobs, using characteristics of incumbents and potential suitability. Seventy female and 66 male college students provided gender and age perceptions for 58 jobs. Results support conceptual and empirical distinctions between perceived incumbent job perceptions and suitability ratings…

  6. Perceptual Scale-Space and Its application

    OpenAIRE

    Yizhou Wang; Siavosh Bahrami; Song-Chun Zhu

    2005-01-01

    When an image is viewed at decreasing resolutions in a Gaussian pyramid, information is lost gradually. Amid continuous intensity changes across scales, there are “quantumjumps” or “perceptual transitions” in our inner representation. In this paper, we study a representational paradigm called the perceptual scale-space which augments the Gaussian pyramid in traditional image scale-space theory by constructing a so-called sketch pyramid. Each level of the sketch pyramid is a generic attribute ...

  7. Aging affects both perceptual and lexical/semantic components of word stem priming: An event-related MRI study

    NARCIS (Netherlands)

    Daselaar, S.M.; Veltman, D.J.; Rombouts, S.A.R.B.; Raaijmakers, J.G.W.; Jonker, C.

    2005-01-01

    In this event-related fMRI study, brain activity patterns were compared in extensive groups of young (N = 25) and older (N = 38) adults, while they were performing a word stem completion priming task. Based on behavioral findings, we tested the hypothesis that aging affects only the lexical/semantic

  8. engAGE in Community: Using Mixed Methods to Mobilize Older People to Elucidate the Age-Friendly Attributes of Urban and Rural Places.

    Science.gov (United States)

    John, Deborah H; Gunter, Katherine

    2016-10-01

    The growing numbers of older adults in the United States will have a significant impact on community resources, which will affect the ability of residents to live and thrive in their local community regardless of age. For this study, we applied explanatory sequential mixed methods and community-based participatory research (CBPR) to discover how attributes of the physical, social, and service environments determine residents' perceptions of community age-friendliness and conditions for aging-in-place. A population survey measuring county residents' (n = 387) perceptions and importance of community resources that support community livability are explained by thematic results of the CBPR, that is, emergent proximal and distal age-friendly factors. Our qualitative approach engaged local people (n = 237) in participatory processes to study and share perceptions of environmental attributes in six communities in one Oregon county. Findings are integrated to explain similarities and differences in older residents' lived experience of rural and urban settings with regard to age-friendly foci. PMID:25608869

  9. Effect of hot-attribute aged ginger tea on chinese medical pulse condition of healthy young humans.

    Science.gov (United States)

    Chao, Dan-Ping; Tyan, Chu-Chang; Chen, Jian-Jung; Hsieh, Ching-Liang; Sheen, Lee-Yan

    2011-10-01

    Young individuals typically have a dry-heat ( zào rè) constitution and feel overly stimulated. This study observes specialties on the right-bar ( yòu guān) section of the radial-arterial pulse of healthy young subjects, and investigates pulse variations induced by different attribute foods. Chinese medical doctors grouped thirty subjects into heat and non-heat constitutions. Each subject took water, aged ginger tea, and coconut water, well recognized as neutral, hot, and cold drinks, on different visits. The current study observed physiological signals induced by the samples using novel noninvasive sphygmography and a blood pressure monitor. As the baseline bigger percussion wave, dicrotic wave, and area in the sphygmogram of the non-heat constitution subjects, this work suggests that blood vessels of these subjects may be more relaxed than that of the heat constitution ones. Stroke volume increased and pulse pressure decreased in the non-heat constitution subjects after taking aged ginger tea, which may elevate arterial compliance corresponding to maintaining an estimated radial-arterial diameter in our study. However, the percussion wave widened and the valley increased in the heat constitution subjects after taking aged ginger tea. This corresponds to the markedly reduced radial-arterial diameter, indicating tighter blood vessels than the baseline status. Accordingly, this study confirms that selecting foods with attributes opposite to personal constitutions is important for reestablishing a healthy cold-heat balance within the human body. Moreover, novel noninvasive sphygmography may be a useful instrument to classify scientifically the heat personal constitution and the responses to different attribute foods. PMID:24716108

  10. The Role of Visual Perceptual Stress in Primary Mental Ability Aging%视知觉压力在基本心理能力老化中的作用

    Institute of Scientific and Technical Information of China (English)

    毛晓飞; 彭华茂

    2015-01-01

    信息降格说认为,感觉功能老化使认知系统难以获得良好的信息输入,并必须牺牲有限的认知资源获得更好的刺激信息,使能用于认知加工的资源不足,造成认知老化。为探讨感觉功能对基本心理能力老化的作用,该研究采用2(年龄组:年轻、老年组)×4(视知觉压力水平:高、中、低、无噪音)的混合设计,考察年轻、老年组在相同视知觉压力下基本心理能力的年龄差异。结果发现和无噪音条件相比,相同视知觉压力下基本心理能力(数字能力、归纳推理能力)的年龄差异减小,甚至消失,一定程度上支持信息降格说。视觉功能衰退可能是影响基本心理能力老化的重要因素,但这种作用受认知资源的调节。%Sensory function is considered a basic resource for the aging of cognition. According to the information- degradation hypothesis (Schneider & Pichora-Fuller, 2000), the decline of sensory function reduces the input of peripheral stimulating information to the central neural system of older adults, and so more attention resources are demanded to process the limited quality sensory information. With the result of fewer resources being left for cognitive processing, older adults have worse cognitive performance than younger adults. The present study adopted a 2 (age: old and young) × 4 (visual perceptual stress: high, medium, low, no-noise) mixed design, with age as a between-subject variable and visual perceptual stress as a within-subject variable, to examine the role of visual function on cognitive aging. Three primary mental abilities (PMA), spatial orientation ability, numerical ability and inductive reasoning ability, were used as the indexes of cognitive functions. Allcognitive tests were displayed under four different levels of visual perceptual stress by standardized programs on the computer. The visual perceptual stress was created by covering stimuli with Gaussian

  11. Perceptual maps: the good, the bad and the ugly

    OpenAIRE

    Gower, John; Groenen, Patrick; Velden, Michel; Vines, Karen

    2010-01-01

    textabstractPerceptual maps are often used in marketing to visually study relations between two or more attributes. However, in many perceptual maps published in the recent literature it remains unclear what is being shown and how the relations between the points in the map can be interpreted or even what a point represents. The term perceptual map refers to plots obtained by a series of different techniques, such as principal component analysis, (multiple) correspondence analysis, and multid...

  12. How age and linguistic competence alter the interplay of perceptual and cognitive factors when listening to conversations in a noisy environment.

    Science.gov (United States)

    Avivi-Reich, Meital; Daneman, Meredyth; Schneider, Bruce A

    2014-01-01

    Multi-talker conversations challenge the perceptual and cognitive capabilities of older adults and those listening in their second language (L2). In older adults these difficulties could reflect declines in the auditory, cognitive, or linguistic processes supporting speech comprehension. The tendency of L2 listeners to invoke some of the semantic and syntactic processes from their first language (L1) may interfere with speech comprehension in L2. These challenges might also force them to reorganize the ways in which they perceive and process speech, thereby altering the balance between the contributions of bottom-up vs. top-down processes to speech comprehension. Younger and older L1s as well as young L2s listened to conversations played against a babble background, with or without spatial separation between the talkers and masker, when the spatial positions of the stimuli were specified either by loudspeaker placements (real location), or through use of the precedence effect (virtual location). After listening to a conversation, the participants were asked to answer questions regarding its content. Individual hearing differences were compensated for by creating the same degree of difficulty in identifying individual words in babble. Once compensation was applied, the number of questions correctly answered increased when a real or virtual spatial separation was introduced between babble and talkers. There was no evidence that performance differed between real and virtual locations. The contribution of vocabulary knowledge to dialog comprehension was found to be larger in the virtual conditions than in the real whereas the contribution of reading comprehension skill did not depend on the listening environment but rather differed as a function of age and language proficiency. The results indicate that the acoustic scene and the cognitive and linguistic competencies of listeners modulate how and when top-down resources are engaged in aid of speech comprehension. PMID

  13. Perceptual maps: the good, the bad and the ugly

    NARCIS (Netherlands)

    J.C. Gower (John); P.J.F. Groenen (Patrick); M. van de Velden (Michel); K. Vines (Karen)

    2010-01-01

    textabstractPerceptual maps are often used in marketing to visually study relations between two or more attributes. However, in many perceptual maps published in the recent literature it remains unclear what is being shown and how the relations between the points in the map can be interpreted or eve

  14. Perceptually-Inspired Computing

    OpenAIRE

    Ming Lin

    2015-01-01

    Human sensory systems allow individuals to see, hear, touch, and interact with the surrounding physical environment. Understanding human perception and its limit enables us to better exploit the psychophysics of human perceptual systems to design more efficient, adaptive algorithms and develop perceptually-inspired computational models. In this talk, I will survey some of recent efforts on perceptually-inspired computing with applications to crowd simulation and multimodal interaction. In par...

  15. Processing of Perceptual Information Is More Robust than Processing of Conceptual Information in Preschool-Age Children: Evidence from Costs of Switching

    Science.gov (United States)

    Fisher, Anna V.

    2011-01-01

    Is processing of conceptual information as robust as processing of perceptual information early in development? Existing empirical evidence is insufficient to answer this question. To examine this issue, 3- to 5-year-old children were presented with a flexible categorization task, in which target items (e.g., an open red umbrella) shared category…

  16. ViA: a perceptual visualization assistant

    Science.gov (United States)

    Healey, Chris G.; St. Amant, Robert; Elhaddad, Mahmoud S.

    2000-05-01

    This paper describes an automated visualized assistant called ViA. ViA is designed to help users construct perceptually optical visualizations to represent, explore, and analyze large, complex, multidimensional datasets. We have approached this problem by studying what is known about the control of human visual attention. By harnessing the low-level human visual system, we can support our dual goals of rapid and accurate visualization. Perceptual guidelines that we have built using psychophysical experiments form the basis for ViA. ViA uses modified mixed-initiative planning algorithms from artificial intelligence to search of perceptually optical data attribute to visual feature mappings. Our perceptual guidelines are integrated into evaluation engines that provide evaluation weights for a given data-feature mapping, and hints on how that mapping might be improved. ViA begins by asking users a set of simple questions about their dataset and the analysis tasks they want to perform. Answers to these questions are used in combination with the evaluation engines to identify and intelligently pursue promising data-feature mappings. The result is an automatically-generated set of mappings that are perceptually salient, but that also respect the context of the dataset and users' preferences about how they want to visualize their data.

  17. Language and perceptual categorisation

    OpenAIRE

    Davidoff, Jules B.

    2001-01-01

    In a pioneering set of experiments, Rosch investigated the colour processing of a remote traditional culture. It was concluded that colours form universally natural and salient categories. However, our own cross-cultural research, backed up by neuropsychological data and interference studies, indicates that perceptual categories are derived from the words in the speaker's language. The new data support a rather strong version of the Whorfian view that perceptual categories are organized by th...

  18. Perceptual Development of phoneme contrasts in adults and children

    NARCIS (Netherlands)

    Heeren, W.F.L.

    2006-01-01

    The two main questions this dissertation is concerned with are (i) How does perceptual sensitivity develop along a dimension that contrasts two unknown speech sounds, and (ii) Does perceptual development vary with the learner's age? With respect to the first question, two hypotheses were tested. One

  19. Notebook Positioning by Perceptual Map and Laddering Method

    Directory of Open Access Journals (Sweden)

    Mehdi Zaribaf

    2012-01-01

    Full Text Available The purpose of this applied paper is to determine positioning of laptops by perceptual map and laddering method. Data collection method was survey using questionnaire. First by using the views of computer experts of selected brands, including Sony, Acer, Asus, Dell and Msi, 5 among 20 attributes, which were considered more important, were selected through application of factor analysis technique. Then, after classification of these features by laddering technique, they were analyzed by using another questionnaire to determine the position of each brand in the perceptual map. We try to show factors and laptop brands position with regard two factors of price and quality in the resulted perceptual map.

  20. Perceptually-Inspired Computing

    Directory of Open Access Journals (Sweden)

    Ming Lin

    2015-08-01

    Full Text Available Human sensory systems allow individuals to see, hear, touch, and interact with the surrounding physical environment. Understanding human perception and its limit enables us to better exploit the psychophysics of human perceptual systems to design more efficient, adaptive algorithms and develop perceptually-inspired computational models. In this talk, I will survey some of recent efforts on perceptually-inspired computing with applications to crowd simulation and multimodal interaction. In particular, I will present data-driven personality modeling based on the results of user studies, example-guided physics-based sound synthesis using auditory perception, as well as perceptually-inspired simplification for multimodal interaction. These perceptually guided principles can be used to accelerating multi-modal interaction and visual computing, thereby creating more natural human-computer interaction and providing more immersive experiences. I will also present their use in interactive applications for entertainment, such as video games, computer animation, and shared social experience. I will conclude by discussing possible future research directions.

  1. Adolescents' Self-Attributed Moral Emotions Following a Moral Transgression: Relations with Delinquency, Confidence in Moral Judgment and Age

    Science.gov (United States)

    Krettenauer, Tobias; Eichler, Dana

    2006-01-01

    The study investigates adolescents' self-attributed moral emotions following a moral transgression by expanding research with children on the happy-victimizer phenomenon. In a sample of 200 German adolescents from Grades 7, 9, 11, and 13 (M=16.18 years, SD=2.41), participants were confronted with various scenarios describing different moral rule…

  2. Discrete representation of perceptual structure underlying consonant confusions.

    Science.gov (United States)

    Soli, S D; Arabie, P; Carroll, J D

    1986-03-01

    The perceptual representation of speech is generally assumed to be discrete rather than continuous, pointing to the need for general discrete analytic models to represent observed perceptual similarities among speech sounds. The INDCLUS (INdividual Differences CLUStering) model and algorithm [J.D. Carroll and P. Arabie, Psychometrika 48, 157-169 (1983)] can provide this generality, representing symmetric three-way similarity data (stimuli X stimuli X conditions) as an additive combination of overlapping, and generally not hierarchial, clusters whose weights (which are numerical values gauging the importance of the clusters) vary both as a function of the cluster and condition being considered. INDCLUS was used to obtain a discrete representation of underlying perceptual structure in the Miller and Nicely consonant confusion data [G.A. Miller and P.E. Nicely, J. Acoust. Soc. Am. 27, 338-352 (1955)]. A 14-cluster solution accounted for 82.9% of total variance across the 17 listening conditions. The cluster composition and the variations in cluster weights as a function of stimulus degradation were interpreted in terms of the common and unique perceptual attributes of the consonants within each cluster. Low-pass filtering and noise masking selectively degraded unique attributes, especially the cues for place of articulation, while high-pass filtering degraded both unique and common attributes. The clustering results revealed that perceptual similarities among consonants are accurately modeled by additive combinations of their specific and discrete acoustic attributes whose weights are determined by the nature of the stimulus degradation. PMID:3958325

  3. Adaptation and perceptual norms

    Science.gov (United States)

    Webster, Michael A.; Yasuda, Maiko; Haber, Sara; Leonard, Deanne; Ballardini, Nicole

    2007-02-01

    We used adaptation to examine the relationship between perceptual norms--the stimuli observers describe as psychologically neutral, and response norms--the stimulus levels that leave visual sensitivity in a neutral or balanced state. Adapting to stimuli on opposite sides of a neutral point (e.g. redder or greener than white) biases appearance in opposite ways. Thus the adapting stimulus can be titrated to find the unique adapting level that does not bias appearance. We compared these response norms to subjectively defined neutral points both within the same observer (at different retinal eccentricities) and between observers. These comparisons were made for visual judgments of color, image focus, and human faces, stimuli that are very different and may depend on very different levels of processing, yet which share the property that for each there is a well defined and perceptually salient norm. In each case the adaptation aftereffects were consistent with an underlying sensitivity basis for the perceptual norm. Specifically, response norms were similar to and thus covaried with the perceptual norm, and under common adaptation differences between subjectively defined norms were reduced. These results are consistent with models of norm-based codes and suggest that these codes underlie an important link between visual coding and visual experience.

  4. Changes in taste compounds, breaking properties, and sensory attributes during dry aging of beef from Japanese black cattle.

    Science.gov (United States)

    Iida, Fumiko; Miyazaki, Yuki; Tsuyuki, Risako; Kato, Kenichi; Egusa, Ai; Ogoshi, Hiro; Nishimura, Toshihide

    2016-02-01

    Analysis of the quality of highly marbled beef during dry aging for 60days after slaughter showed that the changes in some qualities differed from those of conventional meat. The tenderness of these meats did not change during aging for 50days but then gradually increased until day 60. The juiciness of these meats, as determined by sensory evaluation, did not change during aging for 60days, except for a decrease on day 20. The umami intensity of these meats in the sensory evaluation and the value calculated by Glu and IMP quantification were highest on day 40. This high umami intensity was induced by the synergistic effect of umami compounds such as Glu and IMP. These results for tenderness, juiciness, umami intensity, and flavor intensity suggested that the best duration of dry aging for highly marbled beef was 40days. PMID:26519608

  5. Development of the perceptual span in reading: A longitudinal study.

    Science.gov (United States)

    Sperlich, Anja; Meixner, Johannes; Laubrock, Jochen

    2016-06-01

    The perceptual span is a standard measure of parafoveal processing, which is considered highly important for efficient reading. Is the perceptual span a stable indicator of reading performance? What drives its development? Do initially slower and faster readers converge or diverge over development? Here we present the first longitudinal data on the development of the perceptual span in elementary school children. Using the moving window technique, eye movements of 127 German children in three age groups (Grades 1, 2, and 3 in Year 1) were recorded at two time points (T1 and T2) 1year apart. Introducing a new measure of the perceptual span, nonlinear mixed-effects modeling was used to separate window size effects from asymptotic reading performance. Cross-sectional differences were well replicated longitudinally. Asymptotic reading rate increased monotonously with grade, but in a decelerating fashion. A significant change in the perceptual span was observed only between Grades 2 and 3. Together with results from a cross-lagged panel model, this suggests that the perceptual span increases as a consequence of relatively well-established word reading. Stabilities of observed and predicted reading rates were high after Grade 1, whereas the perceptual span was only moderately stable for all grades. Comparing faster and slower readers as assessed at T1, in general, a pattern of stable between-group differences emerged rather than a compensatory pattern; second and third graders even showed a Matthew effect in reading rate and the perceptual span, respectively. PMID:26950508

  6. Perceptual learning and human expertise

    Science.gov (United States)

    Kellman, Philip J.; Garrigan, Patrick

    2009-06-01

    We consider perceptual learning: experience-induced changes in the way perceivers extract information. Often neglected in scientific accounts of learning and in instruction, perceptual learning is a fundamental contributor to human expertise and is crucial in domains where humans show remarkable levels of attainment, such as language, chess, music, and mathematics. In Section 2, we give a brief history and discuss the relation of perceptual learning to other forms of learning. We consider in Section 3 several specific phenomena, illustrating the scope and characteristics of perceptual learning, including both discovery and fluency effects. We describe abstract perceptual learning, in which structural relationships are discovered and recognized in novel instances that do not share constituent elements or basic features. In Section 4, we consider primary concepts that have been used to explain and model perceptual learning, including receptive field change, selection, and relational recoding. In Section 5, we consider the scope of perceptual learning, contrasting recent research, focused on simple sensory discriminations, with earlier work that emphasized extraction of invariance from varied instances in more complex tasks. Contrary to some recent views, we argue that perceptual learning should not be confined to changes in early sensory analyzers. Phenomena at various levels, we suggest, can be unified by models that emphasize discovery and selection of relevant information. In a final section, we consider the potential role of perceptual learning in educational settings. Most instruction emphasizes facts and procedures that can be verbalized, whereas expertise depends heavily on implicit pattern recognition and selective extraction skills acquired through perceptual learning. We consider reasons why perceptual learning has not been systematically addressed in traditional instruction, and we describe recent successful efforts to create a technology of perceptual

  7. Epidemiological pathology of dementia: attributable-risks at death in the medical research council cognitive function and ageing study

    OpenAIRE

    Matthew, F.E.; Brayne, C; Lowe, J; McKeith, I; Wharton, S.B.; Ince, P.

    2009-01-01

    Editors' Summary Background Losing one's belongings and forgetting people's names is often a normal part of aging. But increasing forgetfulness can also be a sign of dementia, a group of symptoms caused by several disorders that affect the structure of the brain. The commonest form of dementia is Alzheimer disease. In this, protein clumps called plaques and neurofibrillary tangles form in the brain and cause its degeneration. Vascular dementia, in which problems with blood circulation deprive...

  8. Influence of Diet and Postmortem Ageing on Oxidative Stability of Lipids, Myoglobin and Myofibrillar Proteins and Quality Attributes of Gluteus Medius Muscle in Goats

    OpenAIRE

    Adeyemi, Kazeem Dauda; Shittu, Rafiat Morolayo; Sabow, Azad Behnan; Ebrahimi, Mahdi; Sazili, Awis Qurni

    2016-01-01

    This study appraised the effects of dietary blend of 80% canola oil and 20% palm oil and postmortem ageing on oxidative stability, fatty acids and quality attributes of gluteus medius (GM) muscle in goats. Twenty-four Boer bucks were randomly allotted to diet supplemented with 0, 4 and 8% oil blend, fed for 100 days and slaughtered, and the GM muscle was subjected to a 7 d chill storage (4±1°C). Diet had no effect (P> 0.05) on the colour, drip loss, thiobarbituric acid-reactive substances (TB...

  9. Atypicalities in perceptual adaptation in autism do not extend to perceptual causality.

    Directory of Open Access Journals (Sweden)

    Themelis Karaminis

    Full Text Available A recent study showed that adaptation to causal events (collisions in adults caused subsequent events to be less likely perceived as causal. In this study, we examined if a similar negative adaptation effect for perceptual causality occurs in children, both typically developing and with autism. Previous studies have reported diminished adaptation for face identity, facial configuration and gaze direction in children with autism. To test whether diminished adaptive coding extends beyond high-level social stimuli (such as faces and could be a general property of autistic perception, we developed a child-friendly paradigm for adaptation of perceptual causality. We compared the performance of 22 children with autism with 22 typically developing children, individually matched on age and ability (IQ scores. We found significant and equally robust adaptation aftereffects for perceptual causality in both groups. There were also no differences between the two groups in their attention, as revealed by reaction times and accuracy in a change-detection task. These findings suggest that adaptation to perceptual causality in autism is largely similar to typical development and, further, that diminished adaptive coding might not be a general characteristic of autism at low levels of the perceptual hierarchy, constraining existing theories of adaptation in autism.

  10. Perceptual grouping enhances visual plasticity

    OpenAIRE

    T. Mastropasqua; Turatto, M.

    2013-01-01

    Visual perceptual learning, a manifestation of neural plasticity, refers to improvements in performance on a visual task achieved by training. Attention is known to play an important role in perceptual learning, given that the observer's discriminative ability improves only for those stimulus feature that are attended. However, the distribution of attention can be severely constrained by perceptual grouping, a process whereby the visual system organizes the initial retinal input into candidat...

  11. Sensory Underdetermination and Perceptual Constancy

    OpenAIRE

    Crockett, Damon

    2015-01-01

    This project has as its focus a pair of related phenomena central to human perception. The first is the underdetermination of perceptual content by sensor input, and the second is a class of mechanisms designed to transform impoverished sensor input into useful perceptual content, mechanisms commonly called `perceptual constancies'. The goal of this project is to discuss a particularly difficult form of sensory underdetermination I call \\textit{stacking}, a \\textit{co-local} sensory conflatio...

  12. Attributes that best describe Successful Leaders: A Perceptual Analysis

    OpenAIRE

    Spears M.C.; Parker D.F.

    2013-01-01

    Periods with visible examples of organizational failure focus and renew attention on efforts to define successful leadership. As the world economy struggles to recover from the Great Recession, there is often an expression of disappointment or disgust with the leadership of leading businesses and institutions. Are the organizations that were too big to fail also too big to lead? Or instead did our problems arise from a failure of leadership? In the wake of financial collapse and reported mana...

  13. Rheumatic Heart Disease-Attributable Mortality at Ages 5-69 Years in Fiji: A Five-Year, National, Population-Based Record-Linkage Cohort Study.

    Directory of Open Access Journals (Sweden)

    Tom Parks

    Full Text Available Rheumatic heart disease (RHD is considered a major public health problem in developing countries, although scarce data are available to substantiate this. Here we quantify mortality from RHD in Fiji during 2008-2012 in people aged 5-69 years.Using 1,773,999 records derived from multiple sources of routine clinical and administrative data, we used probabilistic record-linkage to define a cohort of 2,619 persons diagnosed with RHD, observed for all-cause mortality over 11,538 person-years. Using relative survival methods, we estimated there were 378 RHD-attributable deaths, almost half of which occurred before age 40 years. Using census data as the denominator, we calculated there were 9.9 deaths (95% CI 9.8-10.0 and 331 years of life-lost (YLL, 95% CI 330.4-331.5 due to RHD per 100,000 person-years, standardised to the portion of the WHO World Standard Population aged 0-69 years. Valuing life using Fiji's per-capita gross domestic product, we estimated these deaths cost United States Dollar $6,077,431 annually. Compared to vital registration data for 2011-2012, we calculated there were 1.6-times more RHD-attributable deaths than the number reported, and found our estimate of RHD mortality exceeded all but the five leading reported causes of premature death, based on collapsed underlying cause-of-death diagnoses.Rheumatic heart disease is a leading cause of premature death as well as an important economic burden in this setting. Age-standardised death rates are more than twice those reported in current global estimates. Linkage of routine data provides an efficient tool to better define the epidemiology of neglected diseases.

  14. Snapshots of Children's Changing Biases during Language Development: Differential Weighting of Perceptual and Linguistic Factors Predicts Noun Age of Acquisition

    Science.gov (United States)

    Ramey, Christopher H.; Chrysikou, Evangelia G.; Reilly, Jamie

    2013-01-01

    Word learning is a lifelong activity constrained by cognitive biases that people possess at particular points in development. Age of acquisition (AoA) is a psycholinguistic variable that may prove useful toward gauging the relative weighting of different phonological, semantic, and morphological factors at different phases of language acquisition…

  15. Aging affects both perceptual and lexical/semantic components of word stem priming: An event-related fMRI study

    NARCIS (Netherlands)

    S.M. Daselaar; D.J. Veltman; S. Rombouts; J.G.W. Raaijmakers; C. Jonker

    2005-01-01

    In this event-related fMRI study, brain activity patterns were compared in extensive groups of young (N=25) and older (N=38) adults, while they were performing a word stem completion priming task. Based on behavioral findings, we tested the hypothesis that aging affects only the lexical/semantic, bu

  16. Perceptual learning in speech

    OpenAIRE

    D. Norris; McQueen, J; Cutler, A.

    2003-01-01

    This study demonstrates that listeners use lexical knowledge in perceptual learning of speech sounds. Dutch listeners first made lexical decisions on Dutch words and nonwords. The final fricative of 20 critical words had been replaced by an ambiguous sound, between [f] and [s]. One group of listeners heard ambiguous [f]-final words (e.g., [WI tlo?], from witlof, chicory) and unambiguous [s]-final words (e.g., naaldbos, pine forest). Another group heard the reverse (e.g., ambiguous [na:ldbo?],...

  17. Perceptual Audio Hashing Functions

    Directory of Open Access Journals (Sweden)

    Emin Anarım

    2005-07-01

    Full Text Available Perceptual hash functions provide a tool for fast and reliable identification of content. We present new audio hash functions based on summarization of the time-frequency spectral characteristics of an audio document. The proposed hash functions are based on the periodicity series of the fundamental frequency and on singular-value description of the cepstral frequencies. They are found, on one hand, to perform very satisfactorily in identification and verification tests, and on the other hand, to be very resilient to a large variety of attacks. Moreover, we address the issue of security of hashes and propose a keying technique, and thereby a key-dependent hash function.

  18. Moderating effects of age, gender and education on the associations of perceived neighborhood environment attributes with accelerometer-based physical activity

    DEFF Research Database (Denmark)

    Van Dyck, Delfien; Cerin, Ester; De Bourdeaudhuij, Ilse;

    2015-01-01

    The study's purpose was to examine age, gender, and education as potential moderators of the associations of perceived neighborhood environment variables with accelerometer-based moderate-to-vigorous physical activity (MVPA). Data were from 7273 adults from 16 sites (11 countries) that were part of...... MVPA in men, and curvilinearly in women. Perceived crime safety was related to MVPA only in women. No moderating relationships were found for education. Overall the associations of adults' perceptions of environmental attributes with MVPA were largely independent of the socio-demographic factors...... examined. These findings are encouraging, suggesting that efforts to optimize the perceived built and social environment may act in a socially-equitable manner to facilitate MVPA....

  19. A study on some motoric and anthropometric attributes of competitive and non - competitive taekwondo athletes between the age group 9 - 12 years

    Directory of Open Access Journals (Sweden)

    Duygu SEVİNÇ

    2015-08-01

    Full Text Available Aim: The aim of this study is to examine some motoric and antrophometric attributes of competitive and non - competitive taekwondo athletes within the age group 9 - 12 years and to det ermine the difference between those two groups. Material and method: 31 competitive and 29 non - competitive licensed taekwondo athletes voluntarily participated in the study. The average ages, heights and weight of competitive and non - competitive athletes w ere 11,16±,93 year, 150,58±17,14 cm and 43,80± 13,97 kg, 9,62±,82 year, 137,31±8,80 cm and 35,24±8,28 kg respectively. Both groups have been practising regularly taekwondo for 2,5 years, 2 days a week and two hours a day. Flamingo balance test, test of dis k touching, sit and reach flexibility test, long jump while standing still, 30 sec sit - up test, bent arm pull - up test and 10x5m push up run, right and left hand grip strength test and 20 m shuttle run of the Eurofit test battery were used. Body fat percen t, body fat mass, fat free mass, body mass index values were measured. Such antrophometric attributes as hand length, calf and femur circumference, arm length, biceps circumference in flexion, arm span length were measured. Results: Results of statistical analyses showed a significant difference between two groups in terms of motoric scores (p<0,01, p<0,001, antrophometric characteristics ( p<0,01, p<0,001, and fat free mass ( p<0,001 in favor of the competitive group. Conclusion: Compared with the no n - competitive group, significant differences in competitive group can be explained by their active participation in competitions.

  20. Perceptual inference and autistic traits

    DEFF Research Database (Denmark)

    Skewes, Joshua; Jegindø, Else-Marie Elmholdt; Gebauer, Line

    2015-01-01

    Autistic people are better at perceiving details. Major theories explain this in terms of bottom-up sensory mechanisms, or in terms of top-down cognitive biases. Recently, it has become possible to link these theories within a common framework. This framework assumes that perception is implicit...... neural inference, combining sensory evidence with prior perceptual knowledge. Within this framework, perceptual differences may occur because of enhanced precision in how sensory evidence is represented, or because sensory evidence is weighted much higher than prior perceptual knowledge...

  1. Moderating effects of age, gender and education on the associations of perceived neighborhood environment attributes with accelerometer-based physical activity: The IPEN adult study.

    Science.gov (United States)

    Van Dyck, Delfien; Cerin, Ester; De Bourdeaudhuij, Ilse; Salvo, Deborah; Christiansen, Lars B; Macfarlane, Duncan; Owen, Neville; Mitas, Josef; Troelsen, Jens; Aguinaga-Ontoso, Ines; Davey, Rachel; Reis, Rodrigo; Sarmiento, Olga L; Schofield, Grant; Conway, Terry L; Sallis, James F

    2015-11-01

    The study's purpose was to examine age, gender, and education as potential moderators of the associations of perceived neighborhood environment variables with accelerometer-based moderate-to-vigorous physical activity (MVPA). Data were from 7273 adults from 16 sites (11 countries) that were part of a coordinated multi-country cross-sectional study. Age moderated the associations of perceived crime safety, and perceiving no major physical barriers to walking, with MVPA: positive associations were only found in older adults. Perceived land use mix-access was linearly (positive) associated with MVPA in men, and curvilinearly in women. Perceived crime safety was related to MVPA only in women. No moderating relationships were found for education. Overall the associations of adults' perceptions of environmental attributes with MVPA were largely independent of the socio-demographic factors examined. These findings are encouraging, suggesting that efforts to optimize the perceived built and social environment may act in a socially-equitable manner to facilitate MVPA. PMID:26454247

  2. Avoidance of Emotionally Arousing Stimuli Predicts Social-Perceptual Impairment in Asperger's Syndrome

    Science.gov (United States)

    Corden, Ben; Chilvers, Rebecca; Skuse, David

    2008-01-01

    We combined eye-tracking technology with a test of facial affect recognition and a measure of self-reported social anxiety in order to explore the aetiology of social-perceptual deficits in Asperger's syndrome (AS). Compared to controls matched for age, IQ and visual-perceptual ability, we found a group of AS adults was impaired in their…

  3. Influência do contexto silábico da palavra no julgamento perceptivo-auditivo do ceceio produzido por pré-escolares Influence of syllabic context in auditory-perceptual ratings of lisping in school age children

    Directory of Open Access Journals (Sweden)

    Viviane Cristina de Castro Marino

    2012-01-01

    Full Text Available OBJETIVOS: investigar a ocorrência do ceceio em fricativas produzidas por crianças com alterações oclusais e analisar a influência do contexto silábico da fricativa no julgamento auditivo do ceceio. M ÉTODO: estudo prospectivo, em que as gravações de 428 palavras, produzidas por 15 crianças (idade média de 5 anos e 1 mês foram julgadas auditivamente por três fonoaudiólogos com experiência no julgamento de alterações de fala. As palavras utilizadas foram constituídas pelas consoantes fricativas não vozeadas, alveolar e pós-alveolar, inseridas em posição tônica, precedida das vogais [i, a, u]. Obteve-se concordância intra-juiz (quase perfeita e inter-juiz (total, 100% previamente à análise dos aspectos de interesse. RESULTADOS: embora presente na fala de todas as crianças, identificou-se ceceio em 25,23% do total das palavras. Houve aumento significante do ceceio para: (a fricativa alveolar em ataque inicial, (b fricativa alveolar em ataque inicial em relação à coda medial (p=0,001 e (c fricativa alveolar em relação à fricativa pós- alveolar (pPURPOSES: to investigate the occurrence of lisping during fricative sounds produced by children with malocclusal and to analyze the influence of the syllabic context of the fricative in the perceptual judgment of lisping. METHOD: this prospective study involved auditory perceptual identification of lisping by three experienced speech-language pathologists who judged 428 recorded words produced by 15 children (mean age of 5y1m. The words included alveolar and post-alveolar unvoiced fricative consonants, produced in initial word position followed by [i, a, u] vowels in the stressed position. Intra (almost perfect and inter (total, 100% judgments were obtained before analyzing the data. RESULTS: although all studied children presented lisping at least during one fricative production, it was identified in 25,23% of the recording analyzed words. A significant increase in lisping

  4. New U-Pb ages and lithochemical attributes of the Ediacaran Rio Doce magmatic arc, Araçuaí confined orogen, southeastern Brazil

    Science.gov (United States)

    Gonçalves, Leonardo; Farina, Federico; Lana, Cristiano; Pedrosa-Soares, Antônio C.; Alkmim, Fernando; Nalini, Hermínio A.

    2014-07-01

    The Araçuaí orogen of southeastern Brazil, together with its counterpart located in Africa, the West Congo belt, formed through closure of a gulf connected to the Adamastor Ocean by the end of the Ediacaran and beginning of the Cambrian. Convergence of the margins of the gulf led to the development of the Rio Doce magmatic arc between 630 Ma and 580 Ma on a continental basement mostly composed of Rhyacian orthogneisses. The Rio Doce arc mainly consists of tonalite-granodiorite batholiths, generally crowded with mafic to dioritic enclaves, and minor gabbronorite-enderbite-charnockite plutons, suggesting mixing processes involving crustal and mantle sources. We investigate the basement, magma sources and emplacement ages of the Rio Doce arc. Our data suggest the arc comprises three main granitic rock groups: i) Opx-bearing rocks mostly of enderbite to charnockite composition; ii) enclave-rich tonalite-granodiorite (ETG); and iii) enclave-poor granite-granodiorite with minor tonalite (GT). The Opx-bearing rocks are magnesian, calc-alkalic to alkali-calcic and metaluminous. Together, the ETG and GT rock groups range in composition from tonalite to granite, are metaluminous to slightly peraluminous, show a predominantly medium- to high-K, expanded calc-alkaline signature, and other geochemical and isotopic attributes typical of a pre-collisional volcanic arc formed on a continental margin setting. Mineralogical, chemical, and geochronological data suggest the involvement of HT-melting of granulitic (H2O-depleted) sources of Rhyacian age for the generation of Opx-bearing granitic rocks, additionally to magma mixing and fractional crystallization processes. In conclusion, the studied rock groups of the Rio Doce arc were likely formed by interactions of mantle and crustal processes, in an active continental margin setting. These processes involved ascent of mantle magmas that induced partial melting on the continental basement represented by the Rhyacian gneisses.

  5. Influence of Diet and Postmortem Ageing on Oxidative Stability of Lipids, Myoglobin and Myofibrillar Proteins and Quality Attributes of Gluteus Medius Muscle in Goats.

    Science.gov (United States)

    Adeyemi, Kazeem Dauda; Shittu, Rafiat Morolayo; Sabow, Azad Behnan; Ebrahimi, Mahdi; Sazili, Awis Qurni

    2016-01-01

    This study appraised the effects of dietary blend of 80% canola oil and 20% palm oil and postmortem ageing on oxidative stability, fatty acids and quality attributes of gluteus medius (GM) muscle in goats. Twenty-four Boer bucks were randomly allotted to diet supplemented with 0, 4 and 8% oil blend, fed for 100 days and slaughtered, and the GM muscle was subjected to a 7 d chill storage (4±1°C). Diet had no effect (P> 0.05) on the colour, drip loss, thiobarbituric acid-reactive substances (TBARS) value, free thiol, carbonyl, myoglobin and metmyoglobin contents, metmyoglobin reducing activity (MRA), antioxidant enzyme activities and abundance of myosin heavy chain (MHC) and actin in the GM muscle in goats. The meat from goats fed 4 and 8% oil blend had higher (Pdiet did not affect (Pdiet, the free thiol and myoglobin contents, concentration of tocopherol and total carotenoids, MHC and MRA in the GM muscle decreased (P< 0.05) while carbonyl content, TBARS, drip loss and metmyoglobin content increased over storage. Dietary blend of 80% canola oil and 20% palm oil beneficially altered tissue lipids without hampering the oxidative stability of chevon. PMID:27138001

  6. Acoustic and Perceptual Cues to Contrastive Stress in Dysarthria

    Science.gov (United States)

    Patel, Rupal; Campellone, Pamela

    2009-01-01

    Purpose: In this study, the authors sought to understand acoustic and perceptual cues to contrastive stress in speakers with dysarthria (DYS) and healthy controls (HC). Method: The production experiment examined the ability of 12 DYS (9 male, 3 female; M = 39 years of age) and 12 age- and gender-matched HC (9 male, 3 female; M = 37.5 years of age)…

  7. The effect of generation on long-term repetition priming in auditory and visual perceptual identification.

    Science.gov (United States)

    Mulligan, Neil W

    2011-05-01

    Perceptual implicit memory is typically most robust when the perceptual processing at encoding matches the perceptual processing required during retrieval. A consistent exception is the robust priming that semantic generation produces on the perceptual identification test (Masson & MacLeod, 2002), a finding which has been attributed to either (1) conceptual influences in this nominally perceptual task, or (2) covert orthographic processing during generative encoding. The present experiments assess these possibilities using both auditory and visual perceptual identification, tests in which participants identify auditory words in noise or rapidly-presented visual words. During the encoding phase of the experiments, participants generated some words and perceived others in an intermixed study list. The perceptual control condition was visual (reading) or auditory (hearing), and varied across participants. The reading and hearing conditions exhibited the expected modality-specificity, producing robust intra-modal priming and non-significant cross-modal priming. Priming in the generate condition depended on the perceptual control condition. With a read control condition, semantic generation produced robust visual priming but no auditory priming. With a hear control condition, the results were reversed: semantic generation produced robust auditory priming but not visual priming. This set of results is not consistent with a straightforward application of either the conceptual-influence or covert-orthography account, and implies that the nature of encoding in the generate condition is influenced by the broader list context. PMID:21388613

  8. Notebook Positioning by Perceptual Map and Laddering Method

    OpenAIRE

    Mehdi Zaribaf; Nora Shameli

    2012-01-01

    The purpose of this applied paper is to determine positioning of laptops by perceptual map and laddering method. Data collection method was survey using questionnaire. First by using the views of computer experts of selected brands, including Sony, Acer, Asus, Dell and Msi, 5 among 20 attributes, which were considered more important, were selected through application of factor analysis technique. Then, after classification of these features by laddering technique, they were analyzed by using ...

  9. Influence of Diet and Postmortem Ageing on Oxidative Stability of Lipids, Myoglobin and Myofibrillar Proteins and Quality Attributes of Gluteus Medius Muscle in Goats.

    Directory of Open Access Journals (Sweden)

    Kazeem Dauda Adeyemi

    Full Text Available This study appraised the effects of dietary blend of 80% canola oil and 20% palm oil and postmortem ageing on oxidative stability, fatty acids and quality attributes of gluteus medius (GM muscle in goats. Twenty-four Boer bucks were randomly allotted to diet supplemented with 0, 4 and 8% oil blend, fed for 100 days and slaughtered, and the GM muscle was subjected to a 7 d chill storage (4±1°C. Diet had no effect (P> 0.05 on the colour, drip loss, thiobarbituric acid-reactive substances (TBARS value, free thiol, carbonyl, myoglobin and metmyoglobin contents, metmyoglobin reducing activity (MRA, antioxidant enzyme activities and abundance of myosin heavy chain (MHC and actin in the GM muscle in goats. The meat from goats fed 4 and 8% oil blend had higher (P< 0.05 concentration of α and γ-tocopherol and abundance of troponin T compared with that from the control goats. The GM muscle from the oil-supplemented goats had lower (P< 0.05 concentration of C16:0 and greater (P< 0.05 concentration of C18:1n-9, C18:3n-3 and C20:5n-3 compared with that from the control goats. Nonetheless, diet did not affect (P< 0.05 the total fatty acid in the GM muscle in goats. Regardless of the diet, the free thiol and myoglobin contents, concentration of tocopherol and total carotenoids, MHC and MRA in the GM muscle decreased (P< 0.05 while carbonyl content, TBARS, drip loss and metmyoglobin content increased over storage. Dietary blend of 80% canola oil and 20% palm oil beneficially altered tissue lipids without hampering the oxidative stability of chevon.

  10. Influence of Diet and Postmortem Ageing on Oxidative Stability of Lipids, Myoglobin and Myofibrillar Proteins and Quality Attributes of Gluteus Medius Muscle in Goats

    Science.gov (United States)

    Adeyemi, Kazeem Dauda; Shittu, Rafiat Morolayo; Sabow, Azad Behnan; Ebrahimi, Mahdi; Sazili, Awis Qurni

    2016-01-01

    This study appraised the effects of dietary blend of 80% canola oil and 20% palm oil and postmortem ageing on oxidative stability, fatty acids and quality attributes of gluteus medius (GM) muscle in goats. Twenty-four Boer bucks were randomly allotted to diet supplemented with 0, 4 and 8% oil blend, fed for 100 days and slaughtered, and the GM muscle was subjected to a 7 d chill storage (4±1°C). Diet had no effect (P> 0.05) on the colour, drip loss, thiobarbituric acid-reactive substances (TBARS) value, free thiol, carbonyl, myoglobin and metmyoglobin contents, metmyoglobin reducing activity (MRA), antioxidant enzyme activities and abundance of myosin heavy chain (MHC) and actin in the GM muscle in goats. The meat from goats fed 4 and 8% oil blend had higher (P< 0.05) concentration of α and γ-tocopherol and abundance of troponin T compared with that from the control goats. The GM muscle from the oil-supplemented goats had lower (P< 0.05) concentration of C16:0 and greater (P< 0.05) concentration of C18:1n-9, C18:3n-3 and C20:5n-3 compared with that from the control goats. Nonetheless, diet did not affect (P< 0.05) the total fatty acid in the GM muscle in goats. Regardless of the diet, the free thiol and myoglobin contents, concentration of tocopherol and total carotenoids, MHC and MRA in the GM muscle decreased (P< 0.05) while carbonyl content, TBARS, drip loss and metmyoglobin content increased over storage. Dietary blend of 80% canola oil and 20% palm oil beneficially altered tissue lipids without hampering the oxidative stability of chevon. PMID:27138001

  11. Listening natively across perceptual domains?

    Science.gov (United States)

    Langus, Alan; Seyed-Allaei, Shima; Uysal, Ertuğrul; Pirmoradian, Sahar; Marino, Caterina; Asaadi, Sina; Eren, Ömer; Toro, Juan M; Peña, Marcela; Bion, Ricardo A H; Nespor, Marina

    2016-07-01

    Our native tongue influences the way we perceive other languages. But does it also determine the way we perceive nonlinguistic sounds? The authors investigated how speakers of Italian, Turkish, and Persian group sequences of syllables, tones, or visual shapes alternating in either frequency or duration. We found strong native listening effects with linguistic stimuli. Speakers of Italian grouped the linguistic stimuli differently from speakers of Turkish and Persian. However, speakers of all languages showed the same perceptual biases when grouping the nonlinguistic auditory and the visual stimuli. The shared perceptual biases appear to be determined by universal grouping principles, and the linguistic differences caused by prosodic differences between the languages. Although previous findings suggest that acquired linguistic knowledge can either enhance or diminish the perception of both linguistic and nonlinguistic auditory stimuli, we found no transfer of native listening effects across auditory domains or perceptual modalities. (PsycINFO Database Record PMID:26820498

  12. Clinical characteristics of patients with persistent postural-perceptual dizziness

    Directory of Open Access Journals (Sweden)

    Roseli Saraiva Moreira Bittar

    2015-06-01

    Full Text Available INTRODUCTION: Persistent postural-perceptual dizziness is the dizziness that lasts for over three months with no clinical explanation for its persistence. The patient's motor response pattern presents changes and most patients manifest significant anxiety. OBJECTIVE: To evaluate the clinical characteristics of patients with persistent postural and perceptual dizziness. METHODS: statistical analysis of clinical aspects of patients with persistent postural-perceptual dizziness. RESULTS: 81 patients, average age: 50.06 ± 12.16 years; female/male ratio: 5.7/1; main reasons for dizziness: visual stimuli (74%, body movements (52%, and sleep deprivation (38%. The most prevalent comorbidities were hypercholesterolemia (31%, migraine headaches (26%, carbohydrate metabolism disorders (22% and cervical syndrome (21%. DHI, State-Trait Anxiety Inventory - Trait, Beck Depression Inventory, and Hospital Anxiety and Depression Scale questionnaires were statistically different (p < 0.05 when compared to controls. 68% demonstrated clinical improvement after treatment with serotonin reuptake inhibitors. CONCLUSION: Persistent postural-perceptual dizziness affects more women than men, with a high associated prevalence of metabolic disorders and migraine. Questionnaires help to identify the predisposition to persistent postural-perceptual dizziness. The prognosis is good with adequate treatment.

  13. Perceptual centres in speech - an acoustic analysis

    Science.gov (United States)

    Scott, Sophie Kerttu

    Perceptual centres, or P-centres, represent the perceptual moments of occurrence of acoustic signals - the 'beat' of a sound. P-centres underlie the perception and production of rhythm in perceptually regular speech sequences. P-centres have been modelled both in speech and non speech (music) domains. The three aims of this thesis were toatest out current P-centre models to determine which best accounted for the experimental data bto identify a candidate parameter to map P-centres onto (a local approach) as opposed to the previous global models which rely upon the whole signal to determine the P-centre the final aim was to develop a model of P-centre location which could be applied to speech and non speech signals. The first aim was investigated by a series of experiments in which a) speech from different speakers was investigated to determine whether different models could account for variation between speakers b) whether rendering the amplitude time plot of a speech signal affects the P-centre of the signal c) whether increasing the amplitude at the offset of a speech signal alters P-centres in the production and perception of speech. The second aim was carried out by a) manipulating the rise time of different speech signals to determine whether the P-centre was affected, and whether the type of speech sound ramped affected the P-centre shift b) manipulating the rise time and decay time of a synthetic vowel to determine whether the onset alteration was had more affect on P-centre than the offset manipulation c) and whether the duration of a vowel affected the P-centre, if other attributes (amplitude, spectral contents) were held constant. The third aim - modelling P-centres - was based on these results. The Frequency dependent Amplitude Increase Model of P-centre location (FAIM) was developed using a modelling protocol, the APU GammaTone Filterbank and the speech from different speakers. The P-centres of the stimuli corpus were highly predicted by attributes of

  14. Accuracy and qualities of real and suggested memories: nonspecific age differences.

    Science.gov (United States)

    Karpel, M E; Hoyer, W J; Toglia, M P

    2001-03-01

    This study examined adult age differences in the accuracy, confidence ratings, and vividness ratings of veridical and suggested memories. After seeing either one or two exposures of a vignette depicting a theft, young adults (M = 19 years) and older adults (M = 73 years) were given misleading information that suggested the presence of particular objects in the episode. Memory accuracy was higher for younger adults than for older adults, and the frequency of falsely reporting the presence of suggested objects was greater for older adults than for young adults. Further, levels of confidence and vividness ratings of the perceptual attributes (colors, locations) of falsely recognized items were higher for older adults than for young adults. Both young adults and older adults used more perceptual references when describing veridical memories than when describing suggested memories. Age differences in the suggestibility of memory were attributed to nonspecific or nondissociated memory aging effects. PMID:11245357

  15. Perceptual Representation : Content, Constancies and Phenomenal Consciousness

    OpenAIRE

    2013-01-01

    Do perceptual constancies and phenomenal consciousness help provide an account of how subjects perceive things in the world? In particular, how can they help make sense of the idea that perceptual content is given in the perspective of a subject? In this essay I work towards understanding, in a scientifically grounded way, how perceptual constancies and phenomenal consciousness - jointly - can make sense of this idea in a very precise way. I discuss Tyler Burge's account of perceptual rep...

  16. Perceptual factors that influence use of computer enhanced visual displays

    Science.gov (United States)

    Littman, David; Boehm-Davis, Debbie

    1993-01-01

    This document is the final report for the NASA/Langley contract entitled 'Perceptual Factors that Influence Use of Computer Enhanced Visual Displays.' The document consists of two parts. The first part contains a discussion of the problem to which the grant was addressed, a brief discussion of work performed under the grant, and several issues suggested for follow-on work. The second part, presented as Appendix I, contains the annual report produced by Dr. Ann Fulop, the Postdoctoral Research Associate who worked on-site in this project. The main focus of this project was to investigate perceptual factors that might affect a pilot's ability to use computer generated information that is projected into the same visual space that contains information about real world objects. For example, computer generated visual information can identify the type of an attacking aircraft, or its likely trajectory. Such computer generated information must not be so bright that it adversely affects a pilot's ability to perceive other potential threats in the same volume of space. Or, perceptual attributes of computer generated and real display components should not contradict each other in ways that lead to problems of accommodation and, thus, distance judgments. The purpose of the research carried out under this contract was to begin to explore the perceptual factors that contribute to effective use of these displays.

  17. Perceptual Learning, Cognition, and Expertise

    Science.gov (United States)

    Kellman, Philip J.; Massey, Christine M.

    2013-01-01

    Recent research indicates that perceptual learning (PL)--experience-induced changes in the way perceivers extract information--plays a larger role in complex cognitive tasks, including abstract and symbolic domains, than has been understood in theory or implemented in instruction. Here, we describe the involvement of PL in complex cognitive tasks…

  18. A role of the human thalamus in predicting the perceptual consequences of eye movements

    Directory of Open Access Journals (Sweden)

    Florian Ostendorf

    2013-04-01

    Full Text Available Internal monitoring of oculomotor commands may help to anticipate and keep track of changes in perceptual input imposed by our eye movements. Neurophysiological studies in non-human primates identified corollary discharge signals of oculomotor commands that are conveyed via thalamus to frontal cortices. We tested whether disruption of these monitoring pathways on the thalamic level impairs the perceptual matching of visual input before and after an eye movement in human subjects. Fourteen patients with focal thalamic stroke and twenty healthy control subjects performed a task requiring a perceptual judgment across eye movements. Subjects reported the apparent displacement of a target cue that jumped unpredictably in sync with a saccadic eye movement. In a critical condition of this task, six patients exhibited clearly asymmetric perceptual performance for rightward versus leftward saccade direction. Furthermore, perceptual judgments in seven patients systematically depended on oculomotor targeting errors, with self-generated targeting errors erroneously attributed to external stimulus jumps. Voxel-based lesion-symptom mapping identified an area in right central thalamus as critical for the perceptual matching of visual space across eye movements. Our findings suggest that trans-thalamic corollary discharge transmission decisively contributes to a correct prediction of the perceptual consequences of oculomotor actions.

  19. Referenceless Prediction of Perceptual Fog Density and Perceptual Image Defogging.

    Science.gov (United States)

    Choi, Lark Kwon; You, Jaehee; Bovik, Alan Conrad

    2015-11-01

    We propose a referenceless perceptual fog density prediction model based on natural scene statistics (NSS) and fog aware statistical features. The proposed model, called Fog Aware Density Evaluator (FADE), predicts the visibility of a foggy scene from a single image without reference to a corresponding fog-free image, without dependence on salient objects in a scene, without side geographical camera information, without estimating a depth-dependent transmission map, and without training on human-rated judgments. FADE only makes use of measurable deviations from statistical regularities observed in natural foggy and fog-free images. Fog aware statistical features that define the perceptual fog density index derive from a space domain NSS model and the observed characteristics of foggy images. FADE not only predicts perceptual fog density for the entire image, but also provides a local fog density index for each patch. The predicted fog density using FADE correlates well with human judgments of fog density taken in a subjective study on a large foggy image database. As applications, FADE not only accurately assesses the performance of defogging algorithms designed to enhance the visibility of foggy images, but also is well suited for image defogging. A new FADE-based referenceless perceptual image defogging, dubbed DEnsity of Fog Assessment-based DEfogger (DEFADE) achieves better results for darker, denser foggy images as well as on standard foggy images than the state of the art defogging methods. A software release of FADE and DEFADE is available online for public use: http://live.ece.utexas.edu/research/fog/index.html. PMID:26186784

  20. Linking perceptual learning with identical stimuli to imagery perceptual learning

    OpenAIRE

    Grzeczkowski, Lukasz; Tartaglia, Elisa; Mast, Fred W.; Herzog, Michael

    2015-01-01

    Perceptual learning is usually thought to be exclusively driven by the stimuli presented during training (and the underlying synaptic learning rules). In some way, we are slaves of our visual experiences. However, learning can occur even when no stimuli are presented at all. For example, Gabor contrast detection improves when only a blank screen is presented and observers are asked to imagine Gabor patches. Likewise, performance improves when observers are asked to imagine the non-existing ce...

  1. Early word meanings: perceptually or functionally based?

    Science.gov (United States)

    Tomikawa, S A; Dodd, D H

    1980-12-01

    The issue of whether early word meaning is based on perceptual (Eve Clark) or functional (Katherine Nelson) features has not been satisfactorily resolved by previous research. The present experiments addressed this issue by presenting young children (2- and 3-year-olds) with novel objects in which perceptual and functional features varied independently. Given choices of how to sort novel artificial objects varying in both aspects, children in experiments 1 and 2 chose perceptual features with few exceptions. Experiments 3 and 4 presented the same objects to children in a concept-learning task, where nonsense labels were to be learned for perceptually or functionally based categories; the latter were much more difficult. Experiment 5 was an extension of the first 2 experiments, except that more familiar objects were employed; comparable results were found. All of the results support 1 conclusion: early conceptualizations and word meanings are perceptually based when perceptual and functional features are independently available. PMID:7471919

  2. How does Learning Impact Development in Infancy? The Case of Perceptual Organization

    OpenAIRE

    Bhatt, Ramesh S.; Quinn, Paul C.

    2011-01-01

    Pattern perception and organization are critical functions of the visual cognition system. Many organizational processes are available early in life, such that infants as young 3 months of age are able to readily utilize a variety of cues to organize visual patterns. However, other processes are not readily evident in young infants, and their development involves perceptual learning. We describe a theoretical framework that addresses perceptual learning in infancy and the manner in which it a...

  3. Broad-based visual benefits from training with an integrated perceptual-learning video game

    OpenAIRE

    Deveau, Jenni; Lovcik, Gary; Aaron R Seitz

    2014-01-01

    Perception is the window through which we understand all information about our environment, and therefore deficits in perception due to disease, injury, stroke or aging can have significant negative impacts on individuals’ lives. Research in the field of perceptual learning has demonstrated that vision can be improved in both normally seeing and visually impaired individuals, however, a limitation of most perceptual learning approaches is their emphasis on isolating particular mechanisms. In ...

  4. Young Drivers Perceptual Learning Styles Preferences and Traffic Accidents

    OpenAIRE

    Čičević, Svetlana; Tubić, Vladan; Nešić, Milkica; Čubranić-Dobrodolac, Marjana

    2011-01-01

    Young drivers are over-represented in crash and fatality statistics. One way of dealing with this problem is to achieve primary prevention through driver education and training. Factors of traffic accidents related to gender, age, driving experience, and self-assessments of safety and their relationship to perceptual learning styles (LS) preferences have been analyzed in this study. The results show that auditory is the most prominent LS. Drivers in general, as well as drivers without traffic...

  5. Perceptual learning, roving and the unsupervised bias

    OpenAIRE

    Herzog, Michael H.; Aberg, Kristoffer C.; Frémaux, Nicolas; Gerstner, Wulfram; Sprekeler, Henning

    2012-01-01

    Perceptual learning improves perception through training. Perceptual learning improves with most stimulus types but fails when certain stimulus types are mixed during training (roving). This result is surprising because classical supervised and unsupervised neural network models can cope easily with roving conditions. What makes humans so inferior compared to these models? As experimental and conceptual work has shown, human perceptual learning is neither supervised nor unsupervised but rewar...

  6. Learning to perceptually organize speech signals in native fashion.

    Science.gov (United States)

    Nittrouer, Susan; Lowenstein, Joanna H

    2010-03-01

    The ability to recognize speech involves sensory, perceptual, and cognitive processes. For much of the history of speech perception research, investigators have focused on the first and third of these, asking how much and what kinds of sensory information are used by normal and impaired listeners, as well as how effective amounts of that information are altered by "top-down" cognitive processes. This experiment focused on perceptual processes, asking what accounts for how the sensory information in the speech signal gets organized. Two types of speech signals processed to remove properties that could be considered traditional acoustic cues (amplitude envelopes and sine wave replicas) were presented to 100 listeners in five groups: native English-speaking (L1) adults, 7-, 5-, and 3-year-olds, and native Mandarin-speaking adults who were excellent second-language (L2) users of English. The L2 adults performed more poorly than L1 adults with both kinds of signals. Children performed more poorly than L1 adults but showed disproportionately better performance for the sine waves than for the amplitude envelopes compared to both groups of adults. Sentence context had similar effects across groups, so variability in recognition was attributed to differences in perceptual organization of the sensory information, presumed to arise from native language experience. PMID:20329861

  7. Stereotype threat prevents perceptual learning

    OpenAIRE

    Rydell, Robert J.; Shiffrin, Richard M.; Boucher, Kathryn L.; Van Loo, Katie; Rydell, Michael T.

    2010-01-01

    Stereotype threat (ST) refers to a situation in which a member of a group fears that her or his performance will validate an existing negative performance stereotype, causing a decrease in performance. For example, reminding women of the stereotype “women are bad at math” causes them to perform more poorly on math questions from the SAT and GRE. Performance deficits can be of several types and be produced by several mechanisms. We show that ST prevents perceptual learning, defined in our task...

  8. Effect of breed and ageing time on meat quality and sensory attributes of veal calves of the "Ternera de Aliste" Quality Label.

    Science.gov (United States)

    Revilla, I; Vivar-Quintana, A M

    2006-06-01

    The effect of breed, sex and ageing time on carcass, meat and eating quality were examined in 32 calves of the "Ternera de Aliste" Spanish Quality Label. Swiss Brown×Alistano-Sanabresa heifers were mated with Charolais or Limousin bulls in order to study the effect of breed. Bull and heifer calves were slaughtered when they were 6-7 months old. Samples of the M. longissimus dorsi were aged for 3, 5 or 7 days and chemical and sensory analyses were done. The results showed no differences due to sex but Charolais sires produced meat which was more tender, juicier and had more odour intensity with a darker colour than meat of the Limousin sired animals. Ageing influenced both sensory and instrumental hardness, colour and odour intensity. After seven days of maturation the meat from such young animals achieved a high quality. PMID:22062288

  9. Test Review No. 16: Test of Perceptual Organization

    Science.gov (United States)

    Proger, Barton B.

    1974-01-01

    Reviewed is the Test of Perceptual Organization, a screening device for difficulties in cognitive functioning, perceptual functioning, perceptual motor ability, and emotional adjustment, which requires that adolescents follow 10 detailed instructions on a street map. (MC)

  10. Attribution of Causes of Weight Loss and Weight Gain to 3-Year Mortality in Older Adults : Results From the Longitudinal Aging Study Amsterdam

    NARCIS (Netherlands)

    Wijnhoven, Hanneke A. H.; van Zon, Sander K. R.; Twisk, Jos; Visser, Marjolein

    2014-01-01

    Background. Weight loss is associated with a higher mortality risk in old age, but the underlying cause may impact this association. We examined associations between causes of intentional and unintentional weight loss and weight gain and mortality. Methods. We used data of five triannual examination

  11. Dynamics of individual perceptual decisions.

    Science.gov (United States)

    Merfeld, Daniel M; Clark, Torin K; Lu, Yue M; Karmali, Faisal

    2016-01-01

    Perceptual decision making is fundamental to a broad range of fields including neurophysiology, economics, medicine, advertising, law, etc. Although recent findings have yielded major advances in our understanding of perceptual decision making, decision making as a function of time and frequency (i.e., decision-making dynamics) is not well understood. To limit the review length, we focus most of this review on human findings. Animal findings, which are extensively reviewed elsewhere, are included when beneficial or necessary. We attempt to put these various findings and data sets, which can appear to be unrelated in the absence of a formal dynamic analysis, into context using published models. Specifically, by adding appropriate dynamic mechanisms (e.g., high-pass filters) to existing models, it appears that a number of otherwise seemingly disparate findings from the literature might be explained. One hypothesis that arises through this dynamic analysis is that decision making includes phasic (high pass) neural mechanisms, an evidence accumulator and/or some sort of midtrial decision-making mechanism (e.g., peak detector and/or decision boundary). PMID:26467513

  12. Collapse models and perceptual processes

    Science.gov (United States)

    Carlo Ghirardi, Gian; Romano, Raffaele

    2014-04-01

    Theories including a collapse mechanism have been presented various years ago. They are based on a modification of standard quantum mechanics in which nonlinear and stochastic terms are added to the evolution equation. Their principal merits derive from the fact that they are mathematically precise schemes accounting, on the basis of a unique universal dynamical principle, both for the quantum behavior of microscopic systems as well as for the reduction associated to measurement processes and for the classical behavior of macroscopic objects. Since such theories qualify themselves not as new interpretations but as modifications of the standard theory they can be, in principle, tested against quantum mechanics. Recently, various investigations identifying possible crucial test have been discussed. In spite of the extreme difficulty to perform such tests it seems that recent technological developments allow at least to put precise limits on the parameters characterizing the modifications of the evolution equation. Here we will simply mention some of the recent investigations in this direction, while we will mainly concentrate our attention to the way in which collapse theories account for definite perceptual process. The differences between the case of reductions induced by perceptions and those related to measurement procedures by means of standard macroscopic devices will be discussed. On this basis, we suggest a precise experimental test of collapse theories involving conscious observers. We make plausible, by discussing in detail a toy model, that the modified dynamics can give rise to quite small but systematic errors in the visual perceptual process.

  13. Collapse models and perceptual processes

    International Nuclear Information System (INIS)

    Theories including a collapse mechanism have been presented various years ago. They are based on a modification of standard quantum mechanics in which nonlinear and stochastic terms are added to the evolution equation. Their principal merits derive from the fact that they are mathematically precise schemes accounting, on the basis of a unique universal dynamical principle, both for the quantum behavior of microscopic systems as well as for the reduction associated to measurement processes and for the classical behavior of macroscopic objects. Since such theories qualify themselves not as new interpretations but as modifications of the standard theory they can be, in principle, tested against quantum mechanics. Recently, various investigations identifying possible crucial test have been discussed. In spite of the extreme difficulty to perform such tests it seems that recent technological developments allow at least to put precise limits on the parameters characterizing the modifications of the evolution equation. Here we will simply mention some of the recent investigations in this direction, while we will mainly concentrate our attention to the way in which collapse theories account for definite perceptual process. The differences between the case of reductions induced by perceptions and those related to measurement procedures by means of standard macroscopic devices will be discussed. On this basis, we suggest a precise experimental test of collapse theories involving conscious observers. We make plausible, by discussing in detail a toy model, that the modified dynamics can give rise to quite small but systematic errors in the visual perceptual process.

  14. Extraction of auditory features and elicitation of attributes for the assessment of multi-channel reproduced sound

    DEFF Research Database (Denmark)

    Choisel, Sylvain; Wickelmaier, Florian

    2005-01-01

    The identification of relevant auditory attributes is pivotal in sound quality evaluation. Two fundamentally different psychometric methods were employed to uncover perceptually relevant auditory features of multi-channel reproduced sound. In the first method, called Repertory Grid Technique (RGT...

  15. Enhanced Perceptual Processing of Speech in Autism

    Science.gov (United States)

    Jarvinen-Pasley, Anna; Wallace, Gregory L.; Ramus, Franck; Happe, Francesca; Heaton, Pamela

    2008-01-01

    Theories of autism have proposed that a bias towards low-level perceptual information, or a featural/surface-biased information-processing style, may compromise higher-level language processing in such individuals. Two experiments, utilizing linguistic stimuli with competing low-level/perceptual and high-level/semantic information, tested…

  16. Reactance and Intentionality Attributions as Determinants of the Intent to File a Grievance.

    Science.gov (United States)

    Gordon, Michael E.; Bowlby, Roger L.

    1989-01-01

    Experimental studies were conducted in two unions to examine the effects of perceptual variables--reactance and intentionality attributions--on the intent to seek redress from management action. Based on participants' responses to a series of vignettes, both studies demonstrated that greater threat and dispositional attributions provoked stronger…

  17. Effects of Protein Restriction on Perceptual-Motor Development, Habituation and Learning.

    Science.gov (United States)

    Elias, Marjorie F.

    Perceptual motor development, habituation, and learning in squirrel monkeys were studied under controlled rearing and diet history conditions to determine whether the animal's level of behavioral development was similar to well-nourished animals of his own age (agemates) or his own size (sizemates). From birth to 8 weeks of age, the animals were…

  18. Causal Attribution of Mood in the Climacterium.

    Science.gov (United States)

    Lyon, Bernadette M.

    1985-01-01

    Examined attributions used by pre- and postmenopausal women (N=105) to explain mood. After reading a diary written by a middle-aged woman, participants rated menopausal symptoms, environment, and age as likely causes of the woman's mood. Menopausal symptoms were rated as a salient source of attribution for negative mood. (NRB)

  19. Facilitation of visual target detection by pre-perceptual processing of negative emotion driven by simple geometric shapes.

    Science.gov (United States)

    Takeshima, Yasuhiro; Gyoba, Jiro

    2016-02-01

    Emotional processing that occurs partially in advance of perceptual processing is known as pre-perceptual emotional processing. The facilitation of sensory processing due to pre-perceptual emotional processing can be observed in visual search and attentional blink tasks. However, previous event-related potential studies have suggested that pre-perceptual emotional processing affects the lower-order range of sensory processing, which differs from the processing involved in visual search and attentional blink tasks. Therefore, we investigated the facilitation of earlier visual processing due to pre-perceptual emotional processing using simple geometric shapes. We found that the target detection sensitivity for a negative emotional stimulus was higher than that for a neutral stimulus. Moreover, this higher sensitivity was not attributed to attentional bias within the visual field or to object novelty. These results suggest that negative emotion induced by simple geometric shapes facilitates visual target detection due to pre-perceptual emotional processing. Furthermore, it was suggested that the facilitation of visual perception by pre-perceptual processing occurs at various stages, from early to later stage. PMID:26537960

  20. A minimalist approach to perceptual interactions

    Directory of Open Access Journals (Sweden)

    Charles Lenay

    2012-05-01

    Starting from our earlier work on perceptual crossing we present a new experiment on the mechanisms of reciprocal recognition of the perceptual intentionality of the other subject: the emergent collective dynamics of the perceptual crossing can be appropriated by each subject. We then present an experimental study of opaque imitation (when the subjects cannot see what they themselves are doing. This study makes it possible to characterize what a properly interactionist approach to imitation might be. In conclusion, we draw on these results, to show how an interactionist approach can contribute to a fully social approach to social cognition.

  1. Speed of perceptual grouping in acquired brain injury.

    Science.gov (United States)

    Kurylo, Daniel D; Larkin, Gabriella Brick; Waxman, Richard; Bukhari, Farhan

    2014-09-01

    Evidence exists that damage to white matter connections may contribute to reduced speed of information processing in traumatic brain injury and stroke. Damage to such axonal projections suggests a particular vulnerability to functions requiring integration across cortical sites. To test this prediction, measurements were made of perceptual grouping, which requires integration of stimulus components. A group of traumatic brain injury and cerebral vascular accident patients and a group of age-matched healthy control subjects viewed arrays of dots and indicated the pattern into which stimuli were perceptually grouped. Psychophysical measurements were made of perceptual grouping as well as processing speed. The patient group showed elevated grouping thresholds as well as extended processing time. In addition, most patients showed progressive slowing of processing speed across levels of difficulty, suggesting reduced resources to accommodate increased demands on grouping. These results support the prediction that brain injury results in a particular vulnerability to functions requiring integration of information across the cortex, which may result from dysfunction of long-range axonal connection. PMID:24820289

  2. Validity and rater reliability of Persian version of the Consensus Auditory Perceptual Evaluation of Voice

    Directory of Open Access Journals (Sweden)

    Nazila Salary Majd

    2014-08-01

    Full Text Available Background and Aim: Auditory-perceptual assessment of voice a main approach in the diagnosis and therapy improvement of voice disorders. Despite, there are few Iranian studies about auditory-perceptual assessment of voice. The aim of present study was development and determination of validity and rater reliability of Persian version of the Consensus Auditory Perceptual Evaluation of Voice (CAPE -V.Methods: The qualitative content validity was detected by collecting 10 questionnaires from 9 experienced speech and language pathologists and a linguist. For reliability purposes, the voice samples of 40 dysphonic (neurogenic, functional with and without laryngeal lesions adults (20-45 years of age and 10 normal healthy speakers were recorded. The samples included sustain of vowels and reading the 6 sentences of Persian version of the consensus auditory perceptual evaluation of voice called the ATSHA.Results: The qualitative content validity was proved for developed Persian version of the consensus auditory perceptual evaluation of voice. Cronbach’s alpha was high (0.95. Intra-rater reliability coefficients ranged from 0.86 for overall severity to 0.42 for pitch; inter-rater reliability ranged from 0.85 for overall severity to 0.32 for pitch (p<0.05.Conclusion: The ATSHA can be used as a valid and reliable Persian scale for auditory perceptual assessment of voice in adults.

  3. Perceptual Training Strongly Improves Visual Motion Perception in Schizophrenia

    Science.gov (United States)

    Norton, Daniel J.; McBain, Ryan K.; Ongur, Dost; Chen, Yue

    2011-01-01

    Schizophrenia patients exhibit perceptual and cognitive deficits, including in visual motion processing. Given that cognitive systems depend upon perceptual inputs, improving patients' perceptual abilities may be an effective means of cognitive intervention. In healthy people, motion perception can be enhanced through perceptual learning, but it…

  4. Data Collection and Analysis Techniques for Evaluating the Perceptual Qualities of Auditory Stimuli

    Energy Technology Data Exchange (ETDEWEB)

    Bonebright, T.L.; Caudell, T.P.; Goldsmith, T.E.; Miner, N.E.

    1998-11-17

    This paper describes a general methodological framework for evaluating the perceptual properties of auditory stimuli. The framework provides analysis techniques that can ensure the effective use of sound for a variety of applications including virtual reality and data sonification systems. Specifically, we discuss data collection techniques for the perceptual qualities of single auditory stimuli including identification tasks, context-based ratings, and attribute ratings. In addition, we present methods for comparing auditory stimuli, such as discrimination tasks, similarity ratings, and sorting tasks. Finally, we discuss statistical techniques that focus on the perceptual relations among stimuli, such as Multidimensional Scaling (MDS) and Pathfinder Analysis. These methods are presented as a starting point for an organized and systematic approach for non-experts in perceptual experimental methods, rather than as a complete manual for performing the statistical techniques and data collection methods. It is our hope that this paper will help foster further interdisciplinary collaboration among perceptual researchers, designers, engineers, and others in the development of effective auditory displays.

  5. Fostering perceptual skills in medical diagnosis

    NARCIS (Netherlands)

    Jarodzka, Halszka; Balslev, Thomas; Holmqvist, Kenneth; Nyström, Marcus; Scheiter, Katharina; Gerjets, Peter; Eika, Berit

    2011-01-01

    Jarodzka, H., Balslev, T., Holmqvist, K., Nyström, M., Scheiter, K., Gerjets, P., & Eika, B. (2011, April). Fostering perceptual skills in medical diagnosis. Meeting of the American Educational Research Association, New Orleans, USA.

  6. The Perceptual Cues that Reshape Expert Reasoning

    Science.gov (United States)

    Harré, Michael; Bossomaier, Terry; Snyder, Allan

    2012-07-01

    The earliest stages in our perception of the world have a subtle but powerful influence on later thought processes; they provide the contextual cues within which our thoughts are framed and they adapt to many different environments throughout our lives. Understanding the changes in these cues is crucial to understanding how our perceptual ability develops, but these changes are often difficult to quantify in sufficiently complex tasks where objective measures of development are available. Here we simulate perceptual learning using neural networks and demonstrate fundamental changes in these cues as a function of skill. These cues are cognitively grouped together to form perceptual templates that enable rapid `whole scene' categorisation of complex stimuli. Such categories reduce the computational load on our capacity limited thought processes, they inform our higher cognitive processes and they suggest a framework of perceptual pre-processing that captures the central role of perception in expertise.

  7. Towards Perceptual Quality Evaluation of Dynamic Meshes

    OpenAIRE

    Torkhani, Fakhri; Wang, Kai; Montanvert, Annick

    2011-01-01

    In practical applications, it is common that a 3D mesh undergoes some lossy operations. Since the end users of 3D meshes are often human beings, it is thus important to derive metrics that can faithfully assess the perceptual distortions induced by these operations. Like in the case of image quality assessment, metrics based on mesh geometric distances (e.g. Hausdorff distance and root mean squared error) cannot correctly predict the visual quality degradation. Recently, several perceptually-...

  8. Perceptual Mapping Using Ordered Logit Analysis

    OpenAIRE

    Hotaka Katahira

    1990-01-01

    This study is to present a new method for constructing a perceptual map based on logit analysis. This is an extension of the explosion logit model of an individual choice to a problem of perceptual mapping giving rise to advantages over existing methods in various aspects. Firstly, input data format is flexible and user-friendly. Unlike traditional methods which typically requires a total dissimilarity ordering on all the pairs of the objects, it allows a partial ordering to any rank depth an...

  9. Perceptual Contrast Enhancement with Dynamic Range Adjustment

    OpenAIRE

    Zhang, Hong; Li, Yuecheng; Chen, Hao; Yuan, Ding; Sun, Mingui

    2013-01-01

    Recent years, although great efforts have been made to improve its performance, few Histogram equalization (HE) methods take human visual perception (HVP) into account explicitly. The human visual system (HVS) is more sensitive to edges than brightness. This paper proposes to take use of this nature intuitively and develops a perceptual contrast enhancement approach with dynamic range adjustment through histogram modification. The use of perceptual contrast connects the image enhancement prob...

  10. Cognitive Penetration, Perceptual Learning and Neural Plasticity

    OpenAIRE

    Cecchi, Ariel Sebastianos

    2014-01-01

    Cognitive penetration of perception, broadly understood, is the influence that the cognitive system has on a perceptual system (e.g., visual, auditory, haptic). The paper shows a form of cognitive penetration in the visual system (defined as early vision) which I call ‘architectural’. Architectural cognitive penetration is the process whereby the behaviour or the structure of the perceptual system is influenced by the cognitive system, which consequently may have an impact on the content of t...

  11. Aging.

    Science.gov (United States)

    Park, Dong Choon; Yeo, Seung Geun

    2013-09-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  12. Enhanced cognitive and perceptual processing: A computational basis for the musician advantage in speech learning

    Directory of Open Access Journals (Sweden)

    Kirsten eSmayda

    2015-05-01

    Full Text Available Long-term music training can positively impact speech processing. A recent framework developed to explain such cross-domain plasticity posits that music training-related advantages in speech processing are due to shared cognitive and perceptual processes between music and speech. Although perceptual and cognitive processing advantages due to music training have been independently demonstrated, to date no study has examined perceptual and cognitive processing within the context of a single task. The present study examines the impact of long-term music training on speech learning from a rigorous, computational perspective derived from signal detection theory. Our computational models provide independent estimates of cognitive and perceptual processing in native English-speaking musicians (n=15, mean age= 25 years and non-musicians (n=15, mean age= 23 years learning to categorize non-native lexical pitch patterns (Mandarin tones. Musicians outperformed non-musicians in this task. Model-based analyses suggested that musicians shifted from simple unidimensional decision strategies to more optimal multidimensional decision strategies sooner than non-musicians. In addition, musicians used optimal decisional strategies more often than non-musicians. However, musicians and non-musicians who used multidimensional strategies showed no difference in performance. We estimated parameters that quantify the magnitude of perceptual variability along two dimensions that are critical for tone categorization: pitch height and pitch direction. Both musicians and non-musicians showed a decrease in perceptual variability along the pitch height dimension, but only musicians showed a significant reduction in perceptual variability along the pitch direction dimension. Notably, these advantages persisted during a generalization phase, when no feedback was provided. These results provide an insight into the mechanisms underlying the musician advantage observed in non

  13. Evaluative pressure overcomes perceptual load effects.

    Science.gov (United States)

    Normand, Alice; Autin, Frédérique; Croizet, Jean-Claude

    2015-06-01

    Perceptual load has been found to be a powerful bottom-up determinant of distractibility, with high perceptual load preventing distraction by any irrelevant information. However, when under evaluative pressure, individuals exert top-down attentional control by giving greater weight to task-relevant features, making them more distractible from task-relevant distractors. One study tested whether the top-down modulation of attention under evaluative pressure overcomes the beneficial bottom-up effect of high perceptual load on distraction. Using a response-competition task, we replicated previous findings that high levels of perceptual load suppress task-relevant distractor response interference, but only for participants in a control condition. Participants under evaluative pressure (i.e., who believed their intelligence was assessed) showed interference from task-relevant distractor at all levels of perceptual load. This research challenges the assumptions of the perceptual load theory and sheds light on a neglected determinant of distractibility: the self-relevance of the performance situation in which attentional control is solicited. PMID:25233881

  14. Perceptually adapted MPEG video encoding

    Science.gov (United States)

    Bordes, Philippe; Guillotel, Philippe

    2000-06-01

    In picture quality assessment, the amount of distortion perceived by a human observer differs from one region to another according to its particular local content. This subjective perception can be explained/predicted by considering some simple psychovisual properties (masking) of the Human Visual System (HVS). We have implemented a HVS model based on a pyramid decomposition for extracting the spatial frequencies, associated with a multi-resolution motion representation. Then the visibility of the decoded errors is computed by exploiting the Kelly's contrast sensitivity spatio-velocity model. The resulting data is called a 'Quality-map.' Special attention has been paid to temporal/moving effects since, in the case of video sequences, motion strongly influences the subjective quality assessment. The quality of the motion information is thus preponderant. In the second part, two possible uses of these psychovisual properties for improving MPEG video encoding performances are depicted: (1) The pre-processing of the pictures to remove non-visible information using a motion adapted filtering. This process is efficient in term of bits saved and degradation is not significant especially on consumer electronic TV sets. (2) A perceptual quantizer based on a local adaptation scheme in order to obtain Quality-maps as uniform as possible (homogeneous perceived distortion), at constant bit-rate. Further improvements have been considered, especially when the viewer is tracking a moving object in the scene.

  15. Uranium Measurements and Attributes

    International Nuclear Information System (INIS)

    It may be necessary to find the means to determine unclassified attributes of uranium in nuclear weapons or their components for future transparency initiatives. We briefly describe the desired characteristics of attribute measurement systems for transparency. The determination of uranium attributes; in particular, by passive gamma-ray detection is a formidable challenge

  16. Healthy Older Observers Show Equivalent Perceptual-Cognitive Training Benefits to Young Adults for Multiple Object Tracking

    OpenAIRE

    Legault, Isabelle; Allard, Rémy; Faubert, Jocelyn

    2013-01-01

    The capacity to process complex dynamic scenes is of critical importance in real life. For instance, traveling through a crowd while avoiding collisions and maintaining orientation and good motor control requires fluent and continuous perceptual-cognitive processing. It is well documented that effects of healthy aging can influence perceptual-cognitive processes (Faubert, 2002) and that the efficiency of such processes can improve with training even for older adults (Richards et al., 2006). H...

  17. Frequent video game players resist perceptual interference.

    Directory of Open Access Journals (Sweden)

    Aaron V Berard

    Full Text Available Playing certain types of video games for a long time can improve a wide range of mental processes, from visual acuity to cognitive control. Frequent gamers have also displayed generalized improvements in perceptual learning. In the Texture Discrimination Task (TDT, a widely used perceptual learning paradigm, participants report the orientation of a target embedded in a field of lines and demonstrate robust over-night improvement. However, changing the orientation of the background lines midway through TDT training interferes with overnight improvements in overall performance on TDT. Interestingly, prior research has suggested that this effect will not occur if a one-hour break is allowed in between the changes. These results have suggested that after training is over, it may take some time for learning to become stabilized and resilient against interference. Here, we tested whether frequent gamers have faster stabilization of perceptual learning compared to non-gamers and examined the effect of daily video game playing on interference of training of TDT with one background orientation on perceptual learning of TDT with a different background orientation. As a result, we found that non-gamers showed overnight performance improvement only on one background orientation, replicating previous results with the interference in TDT. In contrast, frequent gamers demonstrated overnight improvements in performance with both background orientations, suggesting that they are better able to overcome interference in perceptual learning. This resistance to interference suggests that video game playing not only enhances the amplitude and speed of perceptual learning but also leads to faster and/or more robust stabilization of perceptual learning.

  18. Pupil size tracks perceptual content and surprise.

    Science.gov (United States)

    Kloosterman, Niels A; Meindertsma, Thomas; van Loon, Anouk M; Lamme, Victor A F; Bonneh, Yoram S; Donner, Tobias H

    2015-04-01

    Changes in pupil size at constant light levels reflect the activity of neuromodulatory brainstem centers that control global brain state. These endogenously driven pupil dynamics can be synchronized with cognitive acts. For example, the pupil dilates during the spontaneous switches of perception of a constant sensory input in bistable perceptual illusions. It is unknown whether this pupil dilation only indicates the occurrence of perceptual switches, or also their content. Here, we measured pupil diameter in human subjects reporting the subjective disappearance and re-appearance of a physically constant visual target surrounded by a moving pattern ('motion-induced blindness' illusion). We show that the pupil dilates during the perceptual switches in the illusion and a stimulus-evoked 'replay' of that illusion. Critically, the switch-related pupil dilation encodes perceptual content, with larger amplitude for disappearance than re-appearance. This difference in pupil response amplitude enables prediction of the type of report (disappearance vs. re-appearance) on individual switches (receiver-operating characteristic: 61%). The amplitude difference is independent of the relative durations of target-visible and target-invisible intervals and subjects' overt behavioral report of the perceptual switches. Further, we show that pupil dilation during the replay also scales with the level of surprise about the timing of switches, but there is no evidence for an interaction between the effects of surprise and perceptual content on the pupil response. Taken together, our results suggest that pupil-linked brain systems track both the content of, and surprise about, perceptual events. PMID:25754528

  19. PERCEPTUAL CONSTANCY AND CONTEXTUAL ENHANCEMENT CONSTANCIA PERCEPTUAL Y MEJORAMIENTO CONTEXTUAL

    Directory of Open Access Journals (Sweden)

    HERIBERTO AVELINO

    2010-01-01

    Full Text Available The perception of the acoustic world surrounding us very often is different from its physical properties. Our mental representation of the sounds that we are exposed to are not in a one to one correspondence with the sounds we sense. Auditory objects and their environments are categorized and loaded in memory so that recognition of complex dynamic scenes are perceived optimally. Precise identification of voices and linguistic objects are crucial for effective communication. However, the normal context of hearing contains multiple, competing and noisy sources. In such disadvantageous conditions the identity of the percepts is more efficient if they are stored in memory. The results of the present study offer experimental evidence that high-level cognitive processes might constrain basic auditory mechanisms involved in identifying phonemic tone to guarantee perceptual constancy. The results showing a better identification of tones in contexts that are inveresely proportional to their frequency support the idea that peripheral auditory processing enhances the identification of the tones by a general function of contextual contrast.La percepción del mundo acústico que nos rodea es a menudo diferente de sus propiedades físicas. Nuestra representación mental de los sonidos a los que estamos expuestos no están en una correspondencia unívoca con los sonidos que sentimos. Los objetos auditivos y sus contextos son categorizados y acumulados en la memoria de forma tal que el reconocimiento de escenas dinámicas complejas son percibidas óptimamente. La identificación precisa de voces y objetos lingüísticos son cruciales para la comunicación efectiva. Sin embargo, el contexto normal de la escucha contiene fuentes múltiples, con ruido y en competencia. En estas condiciones de desventaja la identidad de los perceptos es más eficiente si son almacenados en la memoria. Los resultados del presente estudio ofrecen evidencia experimental de que

  20. What Matters in Implicit Task Sequence Learning: Perceptual Stimulus Features, Task Sets, or Correlated Streams of Information?

    Science.gov (United States)

    Weiermann, Brigitte; Cock, Josephine; Meier, Beat

    2010-01-01

    Implicit task sequence learning may be attributed to learning the order of perceptual stimulus features associated with the task sequence, learning a series of automatic task set activations, or learning an integrated sequence that derives from 2 correlated streams of information. In the present study, our purpose was to distinguish among these 3…

  1. An Acoustic and Perceptual Study of Final Stops Produced by Profoundly Hearing Impaired Adolescents

    Science.gov (United States)

    Khouw, Edward; Ciocca, Valter

    2006-01-01

    Purpose: This study investigated formant frequencies for their role as acoustic and perceptual correlates to the place of articulation of Cantonese final stops produced by profoundly hearing impaired speakers. Method: Speakers were 10 Cantonese adolescents (mean age = 13;5 [years;months]) who were profoundly hearing impaired (HI). Control speakers…

  2. Perceptual Sensitivity and Conceptual Coordination in Children and Younger and Older Adults.

    Science.gov (United States)

    West, Robin L.; And Others

    1978-01-01

    Studies the effects of perceptual salience on performance in problems requiring the coordination of information. Subjects were groups of children, younger adults, and older adults. For each of the age groups, those problems containing the most salient information were solved faster and more accurately than problems containing the least salient…

  3. Perceptual Development on the Rorschach

    Science.gov (United States)

    O'Neill, Patrick; And Others

    1976-01-01

    The Rorschach was given to 60 school children in two designs: chronological age (CA) and mental age (MA) orthogonal and CA=MA. Responses were scored for Form Accuracy, Complexity, Movement and Friedman's Developmental Level (DL) Scoring System. The results suggest that the DL system does assess MA independently of CA. (Author/DEP)

  4. An Exploration of EFL Teachers' Attributions

    Science.gov (United States)

    Ghonsooly, Behzad; Ghanizadeh, Afsaneh; Ghazanfari, Mohammad; Ghabanchi, Zargham

    2015-01-01

    The present study investigated English as a foreign language (EFL) teachers' attributions of success and failure. It also set out to investigate whether these attributions vary by teachers' age, teaching experience, gender and educational level. To do so, 200 EFL teachers were selected according to convenience sampling among EFL teachers teaching…

  5. Adductor spasmodic dysphonia: Relationships between acoustic indices and perceptual judgments

    Science.gov (United States)

    Cannito, Michael P.; Sapienza, Christine M.; Woodson, Gayle; Murry, Thomas

    2003-04-01

    This study investigated relationships between acoustical indices of spasmodic dysphonia and perceptual scaling judgments of voice attributes made by expert listeners. Audio-recordings of The Rainbow Passage were obtained from thirty one speakers with spasmodic dysphonia before and after a BOTOX injection of the vocal folds. Six temporal acoustic measures were obtained across 15 words excerpted from each reading sample, including both frequency of occurrence and percent time for (1) aperiodic phonation, (2) phonation breaks, and (3) fundamental frequency shifts. Visual analog scaling judgments were also obtained from six voice experts using an interactive computer interface to quantify four voice attributes (i.e., overall quality, roughness, brokenness, breathiness) in a carefully psychoacoustically controlled environment, using the same reading passages as stimuli. Number and percent aperiodicity and phonation breaks correlated significanly with perceived overall voice quality, roughness, and brokenness before and after the BOTOX injection. Breathiness was correlated with aperidocity only prior to injection, while roughness also correlated with frequency shifts following injection. Factor analysis reduced perceived attributes to two principal components: glottal squeezing and breathiness. The acoustic measures demonstrated a strong regression relationship with perceived glottal squeezing, but no regression relationship with breathiness was observed. Implications for an analysis of pathologic voices will be discussed.

  6. Broad-based visual benefits from training with an integrated perceptual-learning video game.

    Science.gov (United States)

    Deveau, Jenni; Lovcik, Gary; Seitz, Aaron R

    2014-06-01

    Perception is the window through which we understand all information about our environment, and therefore deficits in perception due to disease, injury, stroke or aging can have significant negative impacts on individuals' lives. Research in the field of perceptual learning has demonstrated that vision can be improved in both normally seeing and visually impaired individuals, however, a limitation of most perceptual learning approaches is their emphasis on isolating particular mechanisms. In the current study, we adopted an integrative approach where the goal is not to achieve highly specific learning but instead to achieve general improvements to vision. We combined multiple perceptual learning approaches that have individually contributed to increasing the speed, magnitude and generality of learning into a perceptual-learning based video-game. Our results demonstrate broad-based benefits of vision in a healthy adult population. Transfer from the game includes; improvements in acuity (measured with self-paced standard eye-charts), improvement along the full contrast sensitivity function, and improvements in peripheral acuity and contrast thresholds. The use of this type of this custom video game framework built up from psychophysical approaches takes advantage of the benefits found from video game training while maintaining a tight link to psychophysical designs that enable understanding of mechanisms of perceptual learning and has great potential both as a scientific tool and as therapy to help improve vision. PMID:24406157

  7. Well-Founded Belief and Perceptual Justification

    DEFF Research Database (Denmark)

    Broncano-Berrocal, Fernando

    2016-01-01

    According to Alan Millar, justified beliefs are well-founded beliefs. Millar cashes out the notion of well-foundedness in terms of having an adequate reason to believe something and believing it for that reason. To make his account of justified belief compatible with perceptual justification he...... appeals to the notion of recognitional ability. It is argued that, due to the fact that Millar's is a knowledge-first view, his appeal to recognitional abilities fails to offer an explanatory account of familiar cases in the literature and, as a consequence, of the notion of perceptual justification....

  8. Perceptual and Cognitive Impairments and Driving

    Science.gov (United States)

    Korner-Bitensky, Nicol; Coopersmith, Henry; Mayo, Nancy; Leblanc, Ginette; Kaizer, Franceen

    1990-01-01

    Perceptual and cognitive disorders that frequently accompany stroke and head injury influence an individual's ability to drive a motor vehicle. Canadian physicians are legally responsible for identifying patients who are potentially unsafe to drive and, if they fail to do so, may be held liable in a civil action suit. The authors review the guidelines for physicians evaluating a patient's fitness to drive after brain injury. They also examine the actions a physician should take when a patient with perceptual and cognitive problems wants to drive. Ultimately, by taking these actions, physicians will help to prevent driving accidents. PMID:21234047

  9. Attributing illness to food

    DEFF Research Database (Denmark)

    Batz, M. B.; Doyle, M. P.; Morris, J. G.;

    2005-01-01

    the Food Attribution Data Workshop in October 2003 to discuss the virtues and limitations of these approaches and to identify future options for collecting food attribution data in the United States. We summarize workshop discussions and identify challenges that affect progress in this critical......Identification and prioritization of effective food safety interventions require an understanding of the relationship between food and pathogen from farm to consumption. Critical to this cause is food attribution, the capacity to attribute cases of foodborne disease to the food vehicle or other...... source responsible for illness. A wide variety of food attribution approaches and data are used around the world including the analysis of outbreak data, case-control studies, microbial subtyping and source tracking methods, and expert judgment, among others. The Food Safety Research Consortium sponsored...

  10. Valuation, categories and attributes.

    Directory of Open Access Journals (Sweden)

    Inna Galperin

    Full Text Available Existing research on categories has only examined indirectly the value associated with being a member of a category relative to the value of the set of attributes that determine membership in that category. This study uses survey data to analyze consumers' preferences for the "organic" label versus for the attributes underlying that label. We found that consumers generally preferred products with the category label to those with the attributes required for the organic label but without the label. We also found that the value accorded to the organic label increased with the number of attributes that an individual associated with the category. Category membership nevertheless still had greater value than even that of the sum of the attributes associated with it.

  11. Perceptual Object Extraction Based on Saliency and Clustering

    OpenAIRE

    Qiaorong Zhang; Yafeng Zheng; Haibo Liu; Jing Shen; Guochang Gu

    2010-01-01

    Object-based visual attention has received an increasing interest in recent years. Perceptual object is the basic attention unit of object-based visual attention. The definition and extraction of perceptual objects is one of the key technologies in object-based visual attention computation model. A novel perceptual object definition and extraction method is proposed in this paper. Based on Gestalt theory and visual feature integration theory, perceptual object is defined using homogeneity reg...

  12. The attribute measurement technique

    International Nuclear Information System (INIS)

    Any verification measurement performed on potentially classified nuclear material must satisfy two seemingly contradictory constraints. First and foremost, no classified information can be released. At the same time, the monitoring party must have confidence in the veracity of the measurement. An information barrier (IB) is included in the measurement system to protect the potentially classified information while allowing sufficient information transfer to occur for the monitoring party to gain confidence that the material being measured is consistent with the host's declarations, concerning that material. The attribute measurement technique incorporates an IB and addresses both concerns by measuring several attributes of the nuclear material and displaying unclassified results through green (indicating that the material does possess the specified attribute) and red (indicating that the material does not possess the specified attribute) lights. The attribute measurement technique has been implemented in the AVNG, an attribute measuring system described in other presentations at this conference. In this presentation, we will discuss four techniques used in the AVNG: (1) the 1B, (2) the attribute measurement technique, (3) the use of open and secure modes to increase confidence in the displayed results, and (4) the joint design as a method for addressing both host and monitor needs.

  13. Paroxysmal Perceptual Alteration: Drug-Induced Phenomenon or Schizophrenic Psychopathology?

    Science.gov (United States)

    Praharaj, Samir Kumar; Kongasseri, Sreejayan; Acharya, Mahima

    2016-01-01

    Brief and repetitive episodes of perceptual changes, termed paroxysmal perceptual alteration (PPA), have been described in association with antipsychotic treatment. We report a case of paranoid schizophrenia who had such perceptual changes akin to PPA for 15 years, which was not related to antipsychotic treatment. There was a rapid resolution of PPA after treatment with low-dose clonazepam. PMID:26954463

  14. Reading Speed in the peripheral visual field of older adults: Does it benefit from perceptual learning?

    OpenAIRE

    Yu, Deyue; Cheung, Sing-Hang; Legge, Gordon E.; Chung, Susana T. L.

    2010-01-01

    Enhancing reading ability in peripheral vision is important for the rehabilitation of people with central-visual-field loss from age-related macular degeneration (AMD). Previous research has shown that perceptual learning, based on a trigram letter-recognition task, improved peripheral reading speed among normally-sighted young adults (Chung, Legge, & Cheung, 2004). Here we ask whether the same happens in older adults in an age range more typical of the onset of AMD. Eighteen normally-sighted...

  15. The Mirage of the Perceptually Handicapped Syndrome

    Science.gov (United States)

    West, Malcolm

    1970-01-01

    Emphasize the importance of a positive diagnosis of perceptual handicap, rather than a wastebasket" diagnosis. The tendency to separate the child's handicap from his feelings about it is reflected in the treatment process. There exists little concern with the totality of the child's development in his total environment. (Author)

  16. Infant Memory for Primitive Perceptual Features.

    Science.gov (United States)

    Adler, Scott A.

    Textons are elongated blobs of specific color, angular orientation, ends of lines, and crossings of line segments that are proposed to be the perceptual building blocks of the visual system. A study was conducted to explore the relative memorability of different types and arrangements of textons, exploring the time course for the discrimination…

  17. Perceptual and performance biases in action selection

    NARCIS (Netherlands)

    A. Wilson; E. van Bergen; L. van Swieten; S. Kent; M. Mon-Williams

    2008-01-01

    When we see an object in the world, there may be a large number of different ways to interact with that object. This large 'visuomotor space' can be constrained through affordances (perceptually available object properties defining potential uses), task demands and the actor's intentions. The effect

  18. Perceptual evaluation of different image fusion schemes

    NARCIS (Netherlands)

    Toet, A.; IJspeert, J.K.

    2001-01-01

    Human perceptual performance was tested with images of nighttime outdoor scenes. The scenes were registered both with a dual band (visual and near infrared) image intensified low-light CCD camera (DII) and with a thermal middle wavelength band (3-5 μm) infrared (IR) camera. Fused imagery was produce

  19. Stimulus Coding Rules for Perceptual Learning

    OpenAIRE

    Yotsumoto, Yuko; Watanabe, Takeo

    2008-01-01

    Takeo Watanabe and Yuko Yotsumoto explore the implications of a new study that shows that for perceptual learning of visual features involving multiple stimuli to occur, the brain needs to temporally "tag" the features, a learning process that requires paying attention.

  20. Reliability in perceptual analysis of voice quality.

    Science.gov (United States)

    Bele, Irene Velsvik

    2005-12-01

    This study focuses on speaking voice quality in male teachers (n = 35) and male actors (n = 36), who represent untrained and trained voice users, because we wanted to investigate normal and supranormal voices. In this study, both substantial and methodologic aspects were considered. It includes a method for perceptual voice evaluation, and a basic issue was rater reliability. A listening group of 10 listeners, 7 experienced speech-language therapists, and 3 speech-language therapist students evaluated the voices by 15 vocal characteristics using VA scales. Two sets of voice signals were investigated: text reading (2 loudness levels) and sustained vowel (3 levels). The results indicated a high interrater reliability for most perceptual characteristics. Connected speech was evaluated more reliably, especially at the normal level, but both types of voice signals were evaluated reliably, although the reliability for connected speech was somewhat higher than for vowels. Experienced listeners tended to be more consistent in their ratings than did the student raters. Some vocal characteristics achieved acceptable reliability even with a smaller panel of listeners. The perceptual characteristics grouped in 4 factors reflected perceptual dimensions. PMID:16301102

  1. Late Maturation of Auditory Perceptual Learning

    Science.gov (United States)

    Huyck, Julia Jones; Wright, Beverly A.

    2011-01-01

    Adults can improve their performance on many perceptual tasks with training, but when does the response to training become mature? To investigate this question, we trained 11-year-olds, 14-year-olds and adults on a basic auditory task (temporal-interval discrimination) using a multiple-session training regimen known to be effective for adults. The…

  2. Perceptual Learning via Decoded-EEG Neurofeedback

    NARCIS (Netherlands)

    Brandmeyer, A.; Sadakata, M.; Spyrou, L.; McQueen, J.M.; Desain, P.W.M.

    2013-01-01

    An experiment was conducted to determine whether decoding auditory evoked potentials during passive listening and providing the classifier output as a neurofeedback signal leads to the enhancement of auditory perceptual discrimination and/or brain responses related to auditory perception. Results in

  3. Physical and perceptual aspects of percussive timbre

    OpenAIRE

    Brent, William

    2010-01-01

    This dissertation explores relationships between perceptual dimensions of percussive timbres and measurements produced by several signal analysis algorithms. The literature of psychophysical timbre experiments since 1941 is reviewed with respect to two contrasting approaches. The earliest attempts at unraveling the interdependent aspects of timbre perception employed multiple adjective scales intended to describe various sonic features. Following developments in the technique of multidimensio...

  4. Fusion of perceptions for perceptual robotics

    NARCIS (Netherlands)

    Ciftcioglu, O.; Bittermann, M.S.; Sariyildiz, I.S.

    2006-01-01

    Fusion of perception information for perceptual robotics is described. The visual perception is mathematically modelled as a probabilistic process obtaining and interpreting visual data from an environment. The visual data is processed in a multiresolutional form via wavelet transform and optimally

  5. Perceptual-cognitive expertise of handball coaches in their young and middle adult years.

    Science.gov (United States)

    Fischer, Lennart; Baker, Joseph; Rienhoff, Rebecca; Strauß, Bernd; Tirp, Judith; Büsch, Dirk; Schorer, Jörg

    2016-09-01

    There is little research investigating the maintenance of perceptual-cognitive expertise in general and even less comparing coaches of different ages. The aim of this study was to test for perceptual-cognitive differences between age groups, licence levels, and their interaction. This study investigated differences in skilled performance between young and middle-aged coaches of three different skill levels. Participants performed an accuracy-oriented pattern recall (mean distance in pixel) and a time-oriented flicker test (mean detection time in ms). There were some significant differences between age groups and between skill groups for both tests, but no interactions. For the pattern recall test, the effect sizes were larger for skill level differences, while for the flicker test effects were larger for ageing. These results suggest coaches are able to maintain accuracy skills better than reaction timed tasks. This is in line with findings on speeded performance in general populations, which show declines with age. Moreover, results also support findings on perceptual expertise in skills where accuracy was important. PMID:26735929

  6. Attribute coordination in organizations

    OpenAIRE

    Yingyi Qian; Gerard Roland; Chenggang Xu

    2001-01-01

    We study coordination in organizations with a variety of organizational forms. Coordination in organization is modeled as the adjustment of attributes and capacities of tasks when facing external shocks. An M-form (U-form) organization groups complementary (substitutable) tasks together in one unit. In the presence of only attribute shocks, particularly when gains from specialization are small, communication is poor, or shocks are more likely, the expected payoff of the decentralized M-form i...

  7. Perceptual importance analysis for H.264/AVC bit allocation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The existing H.264/AVC rate control schemes rarely include the perceptual considerations. As a result, the improvements in visual quality are hardly comparable to those in peak signal-to-noise ratio (PSNR). In this paper, we propose a perceptual importance analysis scheme to accurately abstract the spatial and temporal perceptual characteristics of video contents. Then we perform bit allocation at macroblock (MB) level by adopting a perceptual mode decision scheme, which adaptively updates the Lagrangian multiplier for mode decision according to the perceptual importance of each MB. Simulation results show that the proposed scheme can efficiently reduce bit rates without visual quality degradation.

  8. Musically cued gait-training improves both perceptual and motor timing in Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Charles-Etienne eBenoit

    2014-07-01

    Full Text Available It is well established that auditory cueing improves gait in patients with Idiopathic Parkinson’s Disease (IPD. Disease-related reductions in speed and step length can be improved by providing rhythmical auditory cues via a metronome or music. However, effects on cognitive aspects of motor control have yet to be thoroughly investigated. If synchronization of movement to an auditory cue relies on a supramodal timing system involved in perceptual, motor and sensorimotor integration, auditory cueing can be expected to affect both motor and perceptual timing. Here we tested this hypothesis by assessing perceptual and motor timing in 15 IPD patients before and after a four-week music training program with rhythmic auditory cueing. Long-term effects were assessed one month after the end of the training. Perceptual and motor timing was evaluated with the Battery for the Assessment of Auditory Sensorimotor and Timing Abilities (BAASTA and compared to that of age-, gender-, and education-matched healthy controls. Prior to training, IPD patients exhibited impaired perceptual and motor timing. Training improved patients’ performance in tasks requiring synchronization with isochronous sequences, and enhanced their ability to adapt to durational changes in a sequence in hand tapping tasks. Benefits of cueing extended to time perception (duration discrimination and detection of misaligned beats in musical excerpts. The current results demonstrate that auditory cueing leads to benefits beyond gait and support the idea that coupling gait to rhythmic auditory cues in IPD patients relies on a neuronal network engaged in both perceptual and motor timing.

  9. Maturation of social attribution skills in typically developing children: An investigation using the social attribution task

    OpenAIRE

    Chan Raymond CK; Hu Zhouyi; McAlonan Grainne M

    2010-01-01

    Abstract Background The assessment of social attribution skills in children can potentially identify and quantify developmental difficulties related to autism spectrum disorders and related conditions. However, relatively little is known about how these skills develop in typically developing children. Therefore the present study aimed to map the trajectory of social attribution skill acquisition in typically developing children from a young age. Methods In the conventional social attribution ...

  10. Population attribute compression

    Science.gov (United States)

    White, James M.; Faber, Vance; Saltzman, Jeffrey S.

    1995-01-01

    An image population having a large number of attributes is processed to form a display population with a predetermined smaller number of attributes that represent the larger number of attributes. In a particular application, the color values in an image are compressed for storage in a discrete look-up table (LUT). Color space containing the LUT color values is successively subdivided into smaller volumes until a plurality of volumes are formed, each having no more than a preselected maximum number of color values. Image pixel color values can then be rapidly placed in a volume with only a relatively few LUT values from which a nearest neighbor is selected. Image color values are assigned 8 bit pointers to their closest LUT value whereby data processing requires only the 8 bit pointer value to provide 24 bit color values from the LUT.

  11. Morphosemantic Attributes of Meetei Proverbs

    Directory of Open Access Journals (Sweden)

    Lourembam Surjit Singh

    2015-06-01

    Full Text Available This study proposes to investigate the functions of morphosemantic in Meetei proverbs, particularly the attribution of different meanings of the lexical items in Meetei Proverbial verbs. Meetei society has been using proverbs in the all ages, stages of development, social changes, and cultural diversifications to mark their wisdom of social expertise. Meetei used proverbs as an important aspect of verbal discourses within the socio-cultural and ethno-civilization contexts in which skills, knowledge, ideas, emotion, and experiences are communicating. The language used in proverbs reflects the Meetei’s status of life, food habits, belief systems, philosophy, cultural and social orientations. At the same time, various meanings attribute in Meetei proverbs in the forms of figurative, witty, pithy, didactic etc. The construction of these forms are grammatically insightful thereby creating spaces for a whole range of possibilities for investigating the features, functions and structure of verbal inflectional markers occurred in Meetei proverbial sentences.Keywords: Proverbs, morphosemantics, features of lexical items, attributes of meanings and language

  12. Implementation aspects of data visualization based on map of attributes

    Directory of Open Access Journals (Sweden)

    Tomasz Rzeźniczak

    2012-12-01

    Full Text Available The aim of this study is to present an original data visualization method with greatest focus on selected aspects of its implementation. The proposed method is designed for visualization of multidimensional data sets consisting of objects described by nominal attributes. The goal of the visualization is to facilitate objects recognition and remembering based on human perceptual capabilities. The expected result for a given input data set is a twodimensional map of all attributes. Arrangement of the attributes on the map allows visualization of individual objects as, so called, good figures. The study is focused on the algorithm, which searches for the optimal maps; implementation aspects and overall complexity of the problem are also explored.

  13. The role of culture in perceptual learning styles

    Directory of Open Access Journals (Sweden)

    حسینی فاطمی ، پیشقدم حسینی فاطمی ، پیشقدم

    2009-01-01

    Full Text Available The major aim of this article is to determine the role of culture in perceptual learning style (PLS preferences of Iranian English learners, in order to minimize teacher-student style conflict in the classroom. To do this, 400 university students from different fields of study were selected from Allameh Tabatabaee University in Tehran, Ferdowsi University of Mashhad and Mashhad University of Medical Sciences. The subjects were asked to answer Reid’s questionnaire (1987 which was designed to specify 6 types of learning styles including: visual, auditory, tactile, kinesthetic, individual and group. The results indicated that: (a the subjects mostly drew on tactile and kinesthetic styles and had the least preference for the individual style of learning. (b No meaningful association was found between gender, age, proficiency and preference for certain style.

  14. Enhancing Cognitive Function Using Perceptual-Cognitive Training.

    Science.gov (United States)

    Parsons, Brendan; Magill, Tara; Boucher, Alexandra; Zhang, Monica; Zogbo, Katrine; Bérubé, Sarah; Scheffer, Olivier; Beauregard, Mario; Faubert, Jocelyn

    2016-01-01

    Three-dimensional multiple object tracking (3D-MOT) is a perceptual-cognitive training system based on a 3D virtual environment. This is the first study to examine the effects of 3D-MOT training on attention, working memory, and visual information processing speed as well as using functional brain imaging on a normative population. Twenty university-aged students were recruited and divided into a training (NT) and nonactive control (CON) group. Cognitive functions were assessed using neuropsychological tests, and correlates of brain functions were assessed using quantitative electroencephalography (qEEG). Results indicate that 10 sessions of 3D-MOT training can enhance attention, visual information processing speed, and working memory, and also leads to quantifiable changes in resting-state neuroelectric brain function. PMID:25550444

  15. Decoding perceptual thresholds from MEG/EEG

    OpenAIRE

    Bekhti, Yousra; Zilber, Nicolas; Pedregosa, Fabian; Ciuciu, Philippe; van Wassenhove, Virginie; Gramfort, Alexandre

    2014-01-01

    Magnetoencephalography (MEG) can map brain activity by recording the electromagnetic fields generated by the electrical currents in the brain during a perceptual or cognitive task. This technique offers a very high temporal resolution that allows noninvasive brain exploration at a millisecond (ms) time scale. Decoding, a.k.a. brain reading, consists in predicting from neuroimaging data the subject's behavior and/or the parameters of the perceived stimuli. This is facilitated by the use of sup...

  16. Progressive Perceptual Audio Rendering of Complex Scenes

    OpenAIRE

    Moeck, Thomas; Bonneel, Nicolas; Tsingos, Nicolas; Drettakis, George; Viaud-Delmon, Isabelle; Aloza, David

    2007-01-01

    Despite recent advances, including sound source clustering and perceptual auditory masking, high quality rendering of complex virtual scenes with thousands of sound sources remains a challenge. Two major bottlenecks appear as the scene complexity increases: the cost of clustering itself, and the cost of pre-mixing source signals within each cluster. In this paper, we first propose an improved hierarchical clustering algorithm that remains efficient for large numbers of sources and clusters wh...

  17. Perceptual uniformity of commonly used color spaces

    Science.gov (United States)

    Avanaki, Ali; Espig, Kathryn; Kimpe, Tom; Xthona, Albert; Marchessoux, Cedric; Rostang, Johan; Piepers, Bastian

    2014-03-01

    Use of color images in medical imaging has increased significantly the last few years. Color information is essential for applications such as ophthalmology, dermatology and clinical photography. Use of color at least brings benefits for other applications such as endoscopy, laparoscopy and digital pathology. Remarkably, as of today, there is no agreed standard on how color information needs to be visualized for medical applications. This lack of standardization results in large variability of how color images are visualized and it makes quality assurance a challenge. For this reason FDA and ICC recently organized a joint summit on color in medical imaging (CMI). At this summit, one of the suggestions was that modalities such as digital pathology could benefit from using a perceptually uniform color space (T. Kimpe, "Color Behavior of Medical Displays," CMI presentation, May 2013). Perceptually uniform spaces have already been used for many years in the radiology community where the DICOM GSDF standard provides linearity in luminance but not in color behavior. In this paper we quantify perceptual uniformity, using CIE's ΔE2000 as a color distance metric, of several color spaces that are typically used for medical applications. We applied our method to theoretical color spaces Gamma 1.8, 2.0, & 2.2, standard sRGB, and DICOM (correction LUT for gray applied to all primaries). In addition, we also measured color spaces (i.e., native behavior) of a high-end medical display (Barco Coronis Fusion 6MP DL, MDCC-6130), and a consumer display (Dell 1907FP). Our results indicate that sRGB & the native color space on the Barco Coronis Fusion exhibit the least non-uniformity within their group. However, the remaining degree of perceptual non-uniformity is still significant and there is room for improvement.

  18. Action-Specific Disruption of Perceptual Confidence

    OpenAIRE

    Stephen M. Fleming; Maniscalco, Brian; Ko, Yoshiaki; Amendi, Namema; Ro, Tony; Lau, Hakwan

    2015-01-01

    Theoretical models of perception assume that confidence is related to the quality or strength of sensory processing. Counter to this intuitive view, we showed in the present research that the motor system also contributes to judgments of perceptual confidence. In two experiments, we used transcranial magnetic stimulation (TMS) to manipulate response-specific representations in the premotor cortex, selectively disrupting postresponse confidence in visual discrimination judgments. Specifically,...

  19. Dynamic Perceptual Changes in Audiovisual Simultaneity

    OpenAIRE

    Kanai, Ryota; Sheth, Bhavin R.; Verstraten, Frans A J; Shimojo, Shinsuke

    2007-01-01

    Background: The timing at which sensory input reaches the level of conscious perception is an intriguing question still awaiting an answer. It is often assumed that both visual and auditory percepts have a modality specific processing delay and their difference determines perceptual temporal offset. Methodology/Principal Findings: Here, we show that the perception of audiovisual simultaneity can change flexibly and fluctuates over a short period of time while subjects observe a constant ...

  20. Perceptual and Cognitive Impairments and Driving

    OpenAIRE

    Korner-Bitensky, Nicol; Coopersmith, Henry; Mayo, Nancy; Leblanc, Ginette; Kaizer, Franceen

    1990-01-01

    Perceptual and cognitive disorders that frequently accompany stroke and head injury influence an individual's ability to drive a motor vehicle. Canadian physicians are legally responsible for identifying patients who are potentially unsafe to drive and, if they fail to do so, may be held liable in a civil action suit. The authors review the guidelines for physicians evaluating a patient's fitness to drive after brain injury. They also examine the actions a physician should take when a patient...

  1. Perceptual digital imaging methods and applications

    CERN Document Server

    Lukac, Rastislav

    2012-01-01

    Visual perception is a complex process requiring interaction between the receptors in the eye that sense the stimulus and the neural system and the brain that are responsible for communicating and interpreting the sensed visual information. This process involves several physical, neural, and cognitive phenomena whose understanding is essential to design effective and computationally efficient imaging solutions. Building on advances in computer vision, image and video processing, neuroscience, and information engineering, perceptual digital imaging greatly enhances the capabilities of tradition

  2. Fusion of perceptions for perceptual robotics

    OpenAIRE

    Ciftcioglu, O.; Bittermann, M.S.; Sariyildiz, I.S.

    2006-01-01

    Fusion of perception information for perceptual robotics is described. The visual perception is mathematically modelled as a probabilistic process obtaining and interpreting visual data from an environment. The visual data is processed in a multiresolutional form via wavelet transform and optimally estimated via extended Kalman filtering in each resolution level and the outcomes are fused for each data block. The measurement involves visual perception in the virtual reality which has direct i...

  3. Advances in visual perceptual learning and plasticity

    OpenAIRE

    Sasaki, Yuka; Nanez, Jose E.; Watanabe, Takeo

    2009-01-01

    Visual perceptual learning (VPL) is defined as a long-term improvement in performance on a visual task. In recent years, the idea that conscious effort is necessary for VPL to occur has been challenged by research suggesting the involvement of more implicit processing mechanisms, such as reinforcement-driven processing and consolidation. In addition, we have learnt much about the neural substrates of VPL and it has become evident that changes in visual areas and regions beyond the visual cort...

  4. Adaptive Criterion Setting in Perceptual Decision Making

    OpenAIRE

    Stüttgen, Maik C.; Yildiz, Ali; Güntürkün, Onur

    2011-01-01

    Pigeons responded in a perceptual categorization task with six different stimuli (shades of gray), three of which were to be classified as “light” or “dark”, respectively. Reinforcement probability for correct responses was varied from 0.2 to 0.6 across blocks of sessions and was unequal for correct light and dark responses. Introduction of a new reinforcement contingency resulted in a biphasic process of adjustment: First, choices were strongly biased towards the favored alternative, which w...

  5. Stimulus coding rules for perceptual learning.

    OpenAIRE

    Jun-Yun Zhang; Shu-Guang Kuai; Lu-Qi Xiao; Klein, Stanley A.; Levi, Dennis M.; Cong Yu

    2008-01-01

    Perceptual learning of visual features occurs when multiple stimuli are presented in a fixed sequence (temporal patterning), but not when they are presented in random order (roving). This points to the need for proper stimulus coding in order for learning of multiple stimuli to occur. We examined the stimulus coding rules for learning with multiple stimuli. Our results demonstrate that: (1) stimulus rhythm is necessary for temporal patterning to take effect during practice; (2) learning conso...

  6. Analysis of Clinicians' Perceptual Cough Evaluation.

    Science.gov (United States)

    Laciuga, Helena; Brandimore, Alexandra E; Troche, Michelle S; Hegland, Karen W

    2016-08-01

    This study examined the relationships between subjective descriptors and objective airflow measures of cough. We hypothesized that coughs with specific airflow characteristics would share common subjective perceptual descriptions. Thirty clinicians (speech-language pathologists, otolaryngologists, and neurologists) perceptually evaluated ten cough audio samples with specific airflow characteristics determined by peak expiratory flow rate, cough expired volume, cough duration, and number of coughs in the cough epoch. Participants rated coughs by strength, duration, quality, quantity, and overall potential effectiveness for airway protection. Perception of cough strength and effectiveness was determined by the combination of presence of pre-expulsive compression phase, short peak expiratory airflow rate rise time, high peak expiratory flow rates, and high cough volume acceleration. Perception of cough abnormality was defined predominantly by descriptors of breathiness and strain. Breathiness was characteristic for coughs with either absent compression phases and relatively high expiratory airflow rates or coughs with significantly low expired volumes and reduced peak flow rates. In contrast, excessive strain was associated with prolonged compression phases and low expiratory airflow rates or the absence of compression phase with high peak expiratory rates. The study participants reached greatest agreement in distinguishing between single and multiple coughs. Their assessment of cough strength and effectiveness was less consistent. Finally, the least agreement was shown in determining the quality categories. Modifications of cough airflow can influence perceptual cough evaluation outcomes. However, the inconsistency of cough ratings among our participants suggests that a uniform cough rating system is required. PMID:27115759

  7. Perceptual asymmetries and handedness: A neglected link?

    Directory of Open Access Journals (Sweden)

    DanieleMarzoli

    2014-02-01

    Full Text Available Healthy individuals tend to weigh in more the left than the right side of visual space in a variety of contexts, ranging from pseudoneglect to perceptual asymmetries for faces. Among the common explanations proposed for the attentional and perceptual advantages of the left visual field, a link with the prevalence of right-handedness in humans has never been suggested, although some evidence seems to converge in favor of a bias of spatial attention towards the region most likely coincident with another person’s right hand during a face-to-face interaction. Such a bias might imply an increased efficiency in monitoring both communicative and aggressive acts, the right limb being more used than the left in both types of behaviour. Although attentional and perceptual asymmetries could be linked to right-handedness at the level of phylogeny because of the evolutionarily advantage of directing attention towards the region where others’ dominant hand usually operates, it is also legitimate to question whether, at the ontogenetic level, frequent exposure to right-handed individuals may foster leftward biases. These views are discussed in the light of extant literature, and a number of tests are proposed in order to assess our hypotheses.

  8. Space and time in perceptual causality

    Directory of Open Access Journals (Sweden)

    Benjamin Straube

    2010-04-01

    Full Text Available Inferring causality is a fundamental feature of human cognition that allows us to theorize about and predict future states of the world. Michotte suggested that humans automatically perceive causality based on certain perceptual features of events. However, individual differences in judgments of perceptual causality cast doubt on Michotte’s view. To gain insights in the neural basis of individual difference in the perception of causality, our participants judged causal relationships in animations of a blue ball colliding with a red ball (a launching event while fMRI-data were acquired. Spatial continuity and temporal contiguity were varied parametrically in these stimuli. We did not find consistent brain activation differences between trials judged as caused and those judged as non-caused, making it unlikely that humans have universal instantiation of perceptual causality in the brain. However, participants were slower to respond to and showed greater neural activity for violations of causality, suggesting that humans are biased to expect causal relationships when moving objects appear to interact. Our participants demonstrated considerable individual differences in their sensitivity to spatial and temporal characteristics in perceiving causality. These qualitative differences in sensitivity to time or space in perceiving causality were instantiated in individual differences in activation of the left basal ganglia or right parietal lobe, respectively. Thus, the perception that the movement of one object causes the movement of another is triggered by elemental spatial and temporal sensitivities, which themselves are instantiated in specific distinct neural networks.

  9. Significant Attributes of Documents.

    Science.gov (United States)

    Armstrong, Frances T.

    The purpose of this paper is to describe a method of finding the significant attributes of documents established during the course of research on the automatic classification of documents. The problem was first approached by examining the way in which an existing hierarchical classification system classifies things. The study of biological…

  10. Attribution of Library Costs

    Science.gov (United States)

    Drake, Miriam A.

    1977-01-01

    Universities conduct a variety of cost-allocation studies that require the collection and analysis of the library cost-data. Cost accounting methods are used in most studies; however, costs are attributed to library user groups in a variety of ways. Cost accounting studies are reviewed and allocation methods are discussed. (Author)

  11. Age, Personality, and the Holtzman Inkblot Technique.

    Science.gov (United States)

    Costa, Paul T., Jr.; McCrae, Robert R.

    1986-01-01

    Investigated age changes and differences in personality as measured by the Holtzman Inkblot Technique (HIT). Concluded that the HIT measures perceptual-cognitive variables that are moderately stable in adulthood. (Author/ABB)

  12. Monocular viewing prolongs reversal interval of perceptual rival figure

    Science.gov (United States)

    Tanahashi, Shigehito; Segawa, Kaori; Zheng, Meihong; Kuze, Junko; Ukai, Kazuhiko

    2012-09-01

    The authors examined whether the perceptual reversal rate changes under monocular versus binocular viewing conditions. Our results suggest that the perceptual reversal interval increases during monocular viewing. The ratio of the reversal rate (1/interval) for the two viewing conditions (binocular/monocular) was 1.28 over a wide range of pattern luminance levels. The quoted ratio was 1.40 when the luminance was high. Such a ratio parallels the value of a well-known binocular summation index (sqrt 2 ), which was derived from the signal detection theory. The binocular summation index shows that the strength of an input signal is enhanced by binocular viewing. However, how the binocular summation shortens the perceptual reversal interval is unclear. This issue can be resolved if the perceptual reversal is derived by integrating the strength of an unconscious image signal. Thus, we discussed the mechanism of perceptual switch by associating two classical, well-studied phenomena, binocular summation and perceptual switch.

  13. Reliability attributes. Survey

    International Nuclear Information System (INIS)

    Starting from an integral system technical concept, the paper gives a survey concerning the treatment of risks relating to reliability by means of the VDI-manual 'Technical Reliability'. Various kinds of reliability characteristics necessary for the determination of risks are explained. Assumed aspects for the evaluation and influencing of attributed risks relating to reliability are stated. Herewith, the formation and application of reliability factors are prepared, which are described on page 2 to 4 of this guideline. (orig./HP)

  14. Auditory-perceptual analysis of voice in abused children and adolescents

    OpenAIRE

    Luciene Stivanin; Fernanda Pontes dos Santos; Christian César Cândido de Oliveira; Bernardo dos Santos; Simone Tozzini Ribeiro; Sandra Scivoletto

    2015-01-01

    Introduction: Abused children and adolescents are exposed to factors that can trigger vocal changes. Objective: This study aimed to analyze the prevalence of vocal changes in abused children and adolescents, through auditory-perceptual analysis of voice and the study of the association between vocal changes, communication disorders, psychiatric disorders, and global functioning. Methods: This was an observational and transversal study of 136 children and adolescents (mean age 10.2 years, 78 m...

  15. Cognitive, perceptual and motor decline as predictors of risky street-crossing decisions in older pedestrians

    OpenAIRE

    LANGEVIN, S; DOMMES, A; CAVALLO, V; Oxley, J; Vienne, F.

    2011-01-01

    Older pedestrians are well known to be over-involved in road crashes compared to younger pedestrians. This study investigates the extent to which risky street-crossing decisions in older pedestrians can be explained by agerelated declines of cognitive, perceptual and physical abilities. Three age groups of participants (young, young-old, old-old) were evaluated in a street-crossing task and performed a series of functional tests. The results showed that agerelated slowing in walking speed as ...

  16. Clinical characteristics of patients with persistent postural-perceptual dizziness

    OpenAIRE

    Roseli Saraiva Moreira Bittar; Eliane Maria Dias von Söhsten Lins

    2015-01-01

    INTRODUCTION: Persistent postural-perceptual dizziness is the dizziness that lasts for over three months with no clinical explanation for its persistence. The patient's motor response pattern presents changes and most patients manifest significant anxiety. OBJECTIVE: To evaluate the clinical characteristics of patients with persistent postural and perceptual dizziness. METHODS: statistical analysis of clinical aspects of patients with persistent postural-perceptual dizziness. RESULTS: 81 pati...

  17. On the Use of Perceptual Properties for Melody Estimation

    OpenAIRE

    Liao, Wei-Hsiang; Su, Alvin. Wen-Yu; Yeh, Chunghsin; Roebel, Axel

    2011-01-01

    This paper is about the use of perceptual principles for melody estimation. The melody stream is understood as generated by the most dominant source. Since the source with the strongest energy may not be perceptually the most dominant one, it is proposed to study the perceptual properties for melody estimation: loudness, masking effect and timbre similarity. The related criteria are integrated into a melody estimation system and their respective contributions are evaluated. The effectiveness ...

  18. Category and Perceptual Learning in Subjects with Treated Wilson's Disease

    OpenAIRE

    Xu, Pengjing; Lu, Zhong-Lin; Wang, Xiaoping; Dosher, Barbara; Zhou, Jiangning; Zhang, Daren; Zhou, Yifeng

    2010-01-01

    To explore the relationship between category and perceptual learning, we examined both category and perceptual learning in patients with treated Wilson's disease (WD), whose basal ganglia, known to be important in category learning, were damaged by the disease. We measured their learning rate and accuracy in rule-based and information-integration category learning, and magnitudes of perceptual learning in a wide range of external noise conditions, and compared the results with those of normal...

  19. Maturation of social attribution skills in typically developing children: an investigation using the social attribution task

    Directory of Open Access Journals (Sweden)

    Chan Raymond CK

    2010-02-01

    Full Text Available Abstract Background The assessment of social attribution skills in children can potentially identify and quantify developmental difficulties related to autism spectrum disorders and related conditions. However, relatively little is known about how these skills develop in typically developing children. Therefore the present study aimed to map the trajectory of social attribution skill acquisition in typically developing children from a young age. Methods In the conventional social attribution task (SAT participants ascribe feelings to moving shapes and describe their interaction in social terms. However, this format requires that participants understand both, that an inanimate shape is symbolic, and that its action is social in nature. This may be challenging for young children, and may be a potential confounder in studies of children with developmental disorders. Therefore we developed a modified SAT (mSAT using animate figures (e.g. animals to simplify the task. We used the SAT and mSAT to examine social attribution skill development in 154 healthy children (76 boys, 78 girls, ranging in age from 6 to 13 years and investigated the relationship between social attribution ability and executive function. Results The mSAT revealed a steady improvement in social attribution skills from the age of 6 years, and a significant advantage for girls compared to boys. In contrast, children under the age of 9 years performed at baseline on the conventional format and there were no gender differences apparent. Performance on neither task correlated with executive function after controlling for age and verbal IQ, suggesting that social attribution ability is independent of cognitive functioning. The present findings indicate that the mSAT is a sensitive measure of social attribution skills from a young age. This should be carefully considered when choosing assessments for young children and those with developmental disorders.

  20. Is it me or not me? Modulation of perceptual-motor awareness and visuomotor performance by mindfulness meditation

    OpenAIRE

    Naranjo José; Schmidt Stefan

    2012-01-01

    Abstract Background Attribution of agency involves the ability to distinguish our own actions and their sensory consequences which are self-generated from those generated by external agents. There are several pathological cases in which motor awareness is dramatically impaired. On the other hand, awareness-enhancement practices like tai-chi and yoga are shown to improve perceptual-motor awareness. Meditation is known to have positive impacts on perception, attention and consciousness itself, ...

  1. Heterogeneity in Perceptual Category Learning by High Functioning Children with Autism Spectrum Disorder

    Directory of Open Access Journals (Sweden)

    Eduardo Mercado

    2015-06-01

    Full Text Available Previous research suggests that high functioning children with Autism Spectrum Disorder (ASD sometimes have problems learning categories, but often appear to perform normally in categorization tasks. The deficits that individuals with ASD show when learning categories have been attributed to executive dysfunction, general deficits in implicit learning, atypical cognitive strategies, or abnormal perceptual biases and abilities. Several of these psychological explanations for category learning deficits have been associated with neural abnormalities such as cortical underconnectivity. The present study evaluated how well existing neurally-based theories account for atypical perceptual category learning shown by high functioning children with ASD across multiple category learning tasks involving novel, abstract shapes. Consistent with earlier results, children’s performances revealed two distinct patterns of learning and generalization associated with ASD: one was indistinguishable from performance in typically developing children; the other revealed dramatic impairments. These two patterns were evident regardless of training regimen or stimulus set. Surprisingly, some children with ASD showed both patterns. Simulations of perceptual category learning could account for the two observed patterns in terms of differences in neural plasticity. However, no current psychological or neural theory adequately explains why a child with ASD might show such large fluctuations in category learning ability across training conditions or stimulus sets.

  2. Perceptual dimensions of style in paintings

    Directory of Open Access Journals (Sweden)

    Marković Slobodan

    2007-01-01

    Full Text Available The main purpose of this study is to specify the basic perceptual dimensions underlying the judgments of the physical features which define the style in paintings (e.g. salient form, colorful surface, oval contours etc.. The other aim of the study is to correlate these dimensions with the subjective (affective dimensions of the experience of paintings. In the preliminary study a set of 25 pairs of elementary perceptual descriptors were empirically specified, and a set of 25 bipolar scales were made (e.g. uncolored-multicolored. In the experiment 30 subjects judged 24 paintings (paintings were taken from the study of Radonjić and Marković, 2004 on 25 scales. Factor analysis revealed the four factors: form (scales: precise, neat, salient form etc., color (color contrast, lightness contrast, vivid colors, space (voluminosity, depth and oval contours and complexity (multicolored, ornate, detailed. Obtained factors reflected the nature of the phenomenological and neural segregation of form, color, depth processing, and partially of complexity processing (e.g. spatial frequency processing within both the form and color subsystem. The aim of the next step of analysis was to specify the correlations between two groups of judgments: (a mean judgments of 24 paintings on perceptual factors and (b mean judgments of the same set of 24 paintings on subjective (affective experience factors, i.e. regularity, attraction, arousal and relaxation (judgments taken from Radonjić and Marković, 2005. The following significant correlations were obtained: regularity-form, regularity-space, attraction-form and arousal-complexity (negative correlation. The reasons for the unexpected negative correlation between arousal and complexity should be specified in further studies.

  3. False Memories Lack Perceptual Detail: Evidence from Implicit Word-Stem Completion and Perceptual Identification Tests

    Science.gov (United States)

    Hicks, J.L.; Starns, J.J.

    2005-01-01

    We used implicit measures of memory to ascertain whether false memories for critical nonpresented items in the DRM paradigm (Deese, 1959; Roediger & McDermott, 1995) contain structural and perceptual detail. In Experiment 1, we manipulated presentation modality in a visual word-stem-completion task. Critical item priming was significant and…

  4. Neuropsychological correlates of school achievement in young children: longitudinal findings with a construct valid perceptual processing instrument.

    Science.gov (United States)

    Melamed, L E; Rugle, L

    1989-10-01

    A form discrimination and a form copying test developed using constructs from basic research in form perception were administered to first-, second-, and third-grade children. Relationships between performance on these tests and achievement scores were investigated both concurrently and over a 2-year follow-up period. These analyses demonstrated the relevance of visual-perceptual factors to academic achievement at all grade levels. Additionally, the pattern of relationships obtained substantiated the existence of age trends in the relationship between perceptual processing factors and academic achievement as has been hypothesized in the child neuropsychology literature. PMID:2808662

  5. Space-restricted attribute grammars

    DEFF Research Database (Denmark)

    Schmidt, Erik Meineche

    1980-01-01

    Restricting the size of attribute values, relative to the length of the string under consideration, leads to a model of attribute grammars in which grammars with both inherited and synthesized attributes can be significantly more economical than grammars with synthesized attributes only....

  6. Moral development and perceptual role-taking egocentrism: their development and interrelationship across the life-span.

    Science.gov (United States)

    Del Vento Bielby, D; Papalia, D E

    1975-01-01

    Moral judgments and perceptual role taking egocentrism were assessed in seventy-two middle-class people whose age range encompassed a significant portion of the life span. Findings support the anticipated curvilinear relationship between moral development and age, and egocentrism and age. However, the close conceptual development and age, and egocentrism and age. However, the close conceptual relationship between moral development and egocentrism throughout life received only slight statistical support, which attained significance only in the fifteen- to nineteen-year-old age group. The existence of "self-involving" egocentrism was postulated to be an important determinant or moral development during adulthood. PMID:1221055

  7. Perceptual organization at attended and unattended locations

    Institute of Scientific and Technical Information of China (English)

    HAN Shihui; Glyn W. Humphreys

    2005-01-01

    This study examined the effects of attention on forming perceptual units by proximity grouping and by uniform connectedness (UC). In Experiment 1 a row of three global letters defined by either proximity or UC was presented at the center of the visual field. Participants were asked to identify the letter in the middle of stimulus arrays while ignoring the flankers. The stimulus onset asynchrony (SOA) between stimulus arrays and masks varied between 180 and 500 ms. We found that responses to targets defined by proximity grouping were slower than to those defined by UC at median SOAs but there were no differences at short or long SOAs. Incongruent flankers slowed responses to targets and this flanker compatibility effect was larger for UC than for proximity-defined flankers. Experiment 2 examined the effects of spatial precueing on discrimination responses to proximity- and UC-defined targets. The advantage for targets defined by UC over targets defined by proximity grouping was greater at uncued relative to cued locations. The results suggest that the advantage for UC over proximity grouping in forming perceptual units is contingent on the stimuli not being fully attended, and that paying attention to the stimuli differentially benefits proximity grouping.

  8. Revisiting the empirical case against perceptual modularity

    Science.gov (United States)

    Masrour, Farid; Nirshberg, Gregory; Schon, Michael; Leardi, Jason; Barrett, Emily

    2015-01-01

    Some theorists hold that the human perceptual system has a component that receives input only from units lower in the perceptual hierarchy. This thesis, that we shall here refer to as the encapsulation thesis, has been at the center of a continuing debate for the past few decades. Those who deny the encapsulation thesis often rely on the large body of psychological findings that allegedly suggest that perception is influenced by factors such as the beliefs, desires, goals, and the expectations of the perceiver. Proponents of the encapsulation thesis, however, often argue that, when correctly interpreted, these psychological findings are compatible with the thesis. In our view, the debate over the significance and the correct interpretation of these psychological findings has reached an impasse. We hold that this impasse is due to the methodological limitations over psychophysical experiments, and it is very unlikely that such experiments, on their own, could yield results that would settle the debate. After defending this claim, we argue that integrating data from cognitive neuroscience resolves the debate in favor of those who deny the encapsulation thesis. PMID:26583001

  9. What is automatized during perceptual categorization?

    Science.gov (United States)

    Roeder, Jessica L; Ashby, F Gregory

    2016-09-01

    An experiment is described that tested whether stimulus-response associations or an abstract rule are automatized during extensive practice at perceptual categorization. Twenty-seven participants each completed 12,300 trials of perceptual categorization, either on rule-based (RB) categories that could be learned explicitly or information-integration (II) categories that required procedural learning. Each participant practiced predominantly on a primary category structure, but every third session they switched to a secondary structure that used the same stimuli and responses. Half the stimuli retained their same response on the primary and secondary categories (the congruent stimuli) and half switched responses (the incongruent stimuli). Several results stood out. First, performance on the primary categories met the standard criteria of automaticity by the end of training. Second, for the primary categories in the RB condition, accuracy and response time (RT) were identical on congruent and incongruent stimuli. In contrast, for the primary II categories, accuracy was higher and RT was lower for congruent than for incongruent stimuli. These results are consistent with the hypothesis that rules are automatized in RB tasks, whereas stimulus-response associations are automatized in II tasks. A cognitive neuroscience theory is proposed that accounts for these results. PMID:27232521

  10. General perceptual contributions to lexical tone normalization.

    Science.gov (United States)

    Huang, Jingyuan; Holt, Lori L

    2009-06-01

    Within tone languages that use pitch variations to contrast meaning, large variability exists in the pitches produced by different speakers. Context-dependent perception may help to resolve this perceptual challenge. However, whether speakers rely on context in contour tone perception is unclear; previous studies have produced inconsistent results. The present study aimed to provide an unambiguous test of the effect of context on contour lexical tone perception and to explore its underlying mechanisms. In three experiments, Mandarin listeners' perception of Mandarin first and second (high-level and mid-rising) tones was investigated with preceding speech and non-speech contexts. Results indicate that the mean fundamental frequency (f0) of a preceding sentence affects perception of contour lexical tones and the effect is contrastive. Following a sentence with a higher-frequency mean f0, the following syllable is more likely to be perceived as a lower frequency lexical tone and vice versa. Moreover, non-speech precursors modeling the mean spectrum of f0 also elicit this effect, suggesting general perceptual processing rather than articulatory-based or speaker-identity-driven mechanisms. PMID:19507980

  11. Implicit Recognition Based on Lateralized Perceptual Fluency

    Directory of Open Access Journals (Sweden)

    Iliana M. Vargas

    2012-02-01

    Full Text Available In some circumstances, accurate recognition of repeated images in an explicit memory test is driven by implicit memory. We propose that this “implicit recognition” results from perceptual fluency that influences responding without awareness of memory retrieval. Here we examined whether recognition would vary if images appeared in the same or different visual hemifield during learning and testing. Kaleidoscope images were briefly presented left or right of fixation during divided-attention encoding. Presentation in the same visual hemifield at test produced higher recognition accuracy than presentation in the opposite visual hemifield, but only for guess responses. These correct guesses likely reflect a contribution from implicit recognition, given that when the stimulated visual hemifield was the same at study and test, recognition accuracy was higher for guess responses than for responses with any level of confidence. The dramatic difference in guessing accuracy as a function of lateralized perceptual overlap between study and test suggests that implicit recognition arises from memory storage in visual cortical networks that mediate repetition-induced fluency increments.

  12. Motivation and intelligence drive auditory perceptual learning.

    Directory of Open Access Journals (Sweden)

    Sygal Amitay

    Full Text Available BACKGROUND: Although feedback on performance is generally thought to promote perceptual learning, the role and necessity of feedback remain unclear. We investigated the effect of providing varying amounts of positive feedback while listeners attempted to discriminate between three identical tones on learning frequency discrimination. METHODOLOGY/PRINCIPAL FINDINGS: Using this novel procedure, the feedback was meaningless and random in relation to the listeners' responses, but the amount of feedback provided (or lack thereof affected learning. We found that a group of listeners who received positive feedback on 10% of the trials improved their performance on the task (learned, while other groups provided either with excess (90% or with no feedback did not learn. Superimposed on these group data, however, individual listeners showed other systematic changes of performance. In particular, those with lower non-verbal IQ who trained in the no feedback condition performed more poorly after training. CONCLUSIONS/SIGNIFICANCE: This pattern of results cannot be accounted for by learning models that ascribe an external teacher role to feedback. We suggest, instead, that feedback is used to monitor performance on the task in relation to its perceived difficulty, and that listeners who learn without the benefit of feedback are adept at self-monitoring of performance, a trait that also supports better performance on non-verbal IQ tests. These results show that 'perceptual' learning is strongly influenced by top-down processes of motivation and intelligence.

  13. Neurological Evidence Linguistic Processes Precede Perceptual Simulation in Conceptual Processing

    Directory of Open Access Journals (Sweden)

    MaxLouwerse

    2012-10-01

    Full Text Available There is increasing evidence from response time experiments that language statistics and perceptual simulations both play a role in conceptual processing. In an EEG experiment we compared neural activity in cortical regions commonly associated with linguistic processing and visual perceptual processing to determine to what extent symbolic and embodied accounts of cognition applied. Participants were asked to determine the semantic relationship of word pairs (e.g., sky – ground or to determine their iconic relationship (i.e., if the presentation of the pair matched their expected physical relationship. A linguistic bias was found towards the semantic judgment task and a perceptual bias was found towards the iconicity judgment task. More importantly, conceptual processing involved activation in brain regions associated with both linguistic and perceptual processes. When comparing the relative activation of linguistic cortical regions with perceptual cortical regions, the effect sizes for linguistic cortical regions were larger than those for the perceptual cortical regions early in a trial with the reverse being true later in a trial. These results map upon findings from other experimental literature and provide further evidence that processing of concept words relies both on language statistics and on perceptual simulations, whereby linguistic processes precede perceptual simulation processes.

  14. Selective Attention to Perceptual Dimensions and Switching between Dimensions

    Science.gov (United States)

    Meiran, Nachshon; Dimov, Eduard; Ganel, Tzvi

    2013-01-01

    In the present experiments, the question being addressed was whether switching attention between perceptual dimensions and selective attention to dimensions are processes that compete over a common resource? Attention to perceptual dimensions is usually studied by requiring participants to ignore a never-relevant dimension. Selection failure…

  15. The Perceptual Abilities Project. Technical Report No. 1988-4.

    Science.gov (United States)

    Bethscheider, Janine K.

    An experimental test battery designed to measure several perceptual abilities was administered to 1,368 (51.8% male) paying clients of the Johnson O'Connor Research Foundation (JOCRF) in an effort to identify and measure three perceptual abilities: (1) flexibility of closure; (2) speed of closure; and (3) spatial scanning. Subjects, who ranged in…

  16. Diagnosis of Auditory Perceptual Disorders in Previously Undiagnosed Adults.

    Science.gov (United States)

    Hasbrouck, Jon M.

    1983-01-01

    Twenty-four adult patients who presented to a number of hospital services with complaints related to difficulty in hearing, understanding, remembering, or writing were examined for auditory perceptual disorders. Results support the desirability of examining auditory perceptual abilities in adults even though the tools available are designed…

  17. Mental imagery of speech implicates two mechanisms of perceptual reactivation.

    Science.gov (United States)

    Tian, Xing; Zarate, Jean Mary; Poeppel, David

    2016-04-01

    Sensory cortices can be activated without any external stimuli. Yet, it is still unclear how this perceptual reactivation occurs and which neural structures mediate this reconstruction process. In this study, we employed fMRI with mental imagery paradigms to investigate the neural networks involved in perceptual reactivation. Subjects performed two speech imagery tasks: articulation imagery (AI) and hearing imagery (HI). We found that AI induced greater activity in frontal-parietal sensorimotor systems, including sensorimotor cortex, subcentral (BA 43), middle frontal cortex (BA 46) and parietal operculum (PO), whereas HI showed stronger activation in regions that have been implicated in memory retrieval: middle frontal (BA 8), inferior parietal cortex and intraparietal sulcus. Moreover, posterior superior temporal sulcus (pSTS) and anterior superior temporal gyrus (aSTG) was activated more in AI compared with HI, suggesting that covert motor processes induced stronger perceptual reactivation in the auditory cortices. These results suggest that motor-to-perceptual transformation and memory retrieval act as two complementary mechanisms to internally reconstruct corresponding perceptual outcomes. These two mechanisms can serve as a neurocomputational foundation for predicting perceptual changes, either via a previously learned relationship between actions and their perceptual consequences or via stored perceptual experiences of stimulus and episodic or contextual regularity. PMID:26889603

  18. Perceptual Learning and Dynamic Changes in Primary Visual Cortex

    OpenAIRE

    Carmel, David; Carrasco, Marisa

    2008-01-01

    Perceptual learning is the improved performance that follows practice in a perceptual task. In this issue of Neuron, Yotsumoto et al. use fMRI to show that stimuli presented at the location used in training initially evoke greater activation in primary visual cortex than stimuli presented elsewhere, but this difference disappears once learning asymptotes.

  19. Perceptual Organization of Visual Structure Requires a Flexible Learning Mechanism

    Science.gov (United States)

    Aslin, Richard N.

    2011-01-01

    Bhatt and Quinn (2011) provide a compelling and comprehensive review of empirical evidence that supports the operation of principles of perceptual organization in young infants. They also have provided a comprehensive list of experiences that could serve to trigger the learning of at least some of these principles of perceptual organization, and…

  20. FEATURES OF LATERALISATION DURING THE PERCEPTION OF EMOTIONAL SPEECH INTONATION OVER THE COURSE OF PERCEPTUAL LEARNING

    Directory of Open Access Journals (Sweden)

    E.S. Dmitrieva

    2013-02-01

    Full Text Available The peculiarities of lateralisation of perception during emotional speech intonation over the course of perceptual learning in adult listeners were studied. Subjects were required to recognise and identify test stimuli in a changing acoustical environment; either a “white noise” background or without noise. The sample consisted of 38 adults (23 females and 15 males with a mean age of 21.1 ± 0.4 years. The reaction time (RT and accuracy of recognition (AR for each subject were recorded in two sequential sessions of trials, after which a generalising index was calculated: relative recognition efficiency (RRE: RRE=AR/RT. An analysis of variance revealed that session sequence was highly significant for RRE. Lateralisation during emotional speech tone recognition over the course of perceptual learning in adults was found to depend on the valence of the emotional intonation and the acoustical environment. These findings confirm the dynamic behaviour of functional asymmetry.

  1. Attributes for Improved Attributes: A Multi-Task Network for Attribute Classification

    OpenAIRE

    Hand, Emily M.; Chellappa, Rama

    2016-01-01

    Attributes, or semantic features, have gained popularity in the past few years in domains ranging from activity recognition in video to face verification. Improving the accuracy of attribute classifiers is an important first step in any application which uses these attributes. In most works to date, attributes have been considered to be independent. However, we know this not to be the case. Many attributes are very strongly related, such as heavy makeup and wearing lipstick. We propose to tak...

  2. Extraction of auditory features and elicitation of attributes for the assessment of multi-channel reproduced sound

    DEFF Research Database (Denmark)

    Choisel, Sylvain; Wickelmaier, Florian Maria

    2005-01-01

    The identification of relevant auditory attributes is pivotal in sound quality evaluation. Two fundamentally different psychometric methods were employed to uncover perceptually relevant auditory features of multichannel reproduced sound. In the first method, called Repertory Grid Technique (RGT)...... sufficient consistency, a lattice representation-as frequently used in Formal Concept Analysis (FCA)-can be derived to depict the structure of auditory features...

  3. Chromatic Perceptual Learning but No Category Effects without Linguistic Input

    Science.gov (United States)

    Grandison, Alexandra; Sowden, Paul T.; Drivonikou, Vicky G.; Notman, Leslie A.; Alexander, Iona; Davies, Ian R. L.

    2016-01-01

    Perceptual learning involves an improvement in perceptual judgment with practice, which is often specific to stimulus or task factors. Perceptual learning has been shown on a range of visual tasks but very little research has explored chromatic perceptual learning. Here, we use two low level perceptual threshold tasks and a supra-threshold target detection task to assess chromatic perceptual learning and category effects. Experiment 1 investigates whether chromatic thresholds reduce as a result of training and at what level of analysis learning effects occur. Experiment 2 explores the effect of category training on chromatic thresholds, whether training of this nature is category specific and whether it can induce categorical responding. Experiment 3 investigates the effect of category training on a higher level, lateralized target detection task, previously found to be sensitive to category effects. The findings indicate that performance on a perceptual threshold task improves following training but improvements do not transfer across retinal location or hue. Therefore, chromatic perceptual learning is category specific and can occur at relatively early stages of visual analysis. Additionally, category training does not induce category effects on a low level perceptual threshold task, as indicated by comparable discrimination thresholds at the newly learned hue boundary and adjacent test points. However, category training does induce emerging category effects on a supra-threshold target detection task. Whilst chromatic perceptual learning is possible, learnt category effects appear to be a product of left hemisphere processing, and may require the input of higher level linguistic coding processes in order to manifest. PMID:27252669

  4. PERUMUSAN STRATEGI BERSAING JAHE INSTAN PRODUK CV. INTRAFOOD SURAKARTA MENGGUNAKAN PERCEPTUAL MAPPING

    Directory of Open Access Journals (Sweden)

    Mohd. Harisudin

    2013-11-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui posisi bersaing jahe instan produk CV. Intrafood dan strategi bersaing yang dapat direkomendasikan untuk meraih keberasilannya. Metode dasar yang digunakan adalah analisis deskriptif. Penentuan lokasi penelitian ditentukan dengan metode purposive, yaitu CV. Intrafood Surakarta. Jenis data yang digunakan dalam penelitian ini adalah data primer dan data sekunder. Metode analisis data menggunakan analisis Perceptual Mapping. Dari hasil penelitian diperoleh informasi bahwa jahe instan produk CV Intrafood berada pada peringkat ke-2 dari produk empat jahe instan yang diperbandingkan. Atribut yang dapat dijadikan kekuatan utama dalam meningkatkan pemasaran jahe instan produk CV. Intrafood adalah manfaat produk. Sisi yang paling lemah adalah atribut desain kemasan dan kinerja produk dalam kemasan. Abstract This study aims to determine the competitive position of the product instant ginger CV. Intrafood and competitive strategy can be recommended to achieve success. The basic method used is descriptive analysis. Determining the location of the study are determined by purposive method, namely CV. Intrafood Surakarta. Data used in this study is primary data and secondary data. Method analyzed using Perceptual Mapping. From the results of the study concluded that instant ginger of CV Intrafood product ranks second of four instant ginger products are compared. Attributes that can be used as a major force in improving product marketing instant ginger CV. Intrafood is the benefits of the product. The weakest side is the packaging design and performance attributes of the product in the packaging.

  5. Atypicalities in Perceptual Adaptation in Autism Do Not Extend to Perceptual Causality

    OpenAIRE

    Themelis Karaminis; Marco Turi; Louise Neil; Badcock, Nicholas A.; David Burr; Elizabeth Pellicano

    2015-01-01

    A recent study showed that adaptation to causal events (collisions) in adults caused subsequent events to be less likely perceived as causal. In this study, we examined if a similar negative adaptation effect for perceptual causality occurs in children, both typically developing and with autism. Previous studies have reported diminished adaptation for face identity, facial configuration and gaze direction in children with autism. To test whether diminished adaptive coding exten...

  6. Perceptual and behavioral adjustments after action inhibition.

    Science.gov (United States)

    Kirsch, Wladimir; Kunde, Wilfried

    2015-10-01

    Inhibiting a motor action typically prompts a more cautious action mode, leaning toward accuracy rather than speed. In the present study, we explored whether action inhibition is also accompanied by changes of visual perception. Our participants performed goal-directed hand movements from a start to a target position and then judged the start-target distance. On a proportion of the trials, movement execution had to be stopped before the target position was reached. The results of two experiments revealed smaller start-target distance estimates after interrupted than after unrestricted movements. Moreover, movement amplitudes were decreased in movements that followed interrupted ones. In line with the predictions of action-specific accounts of perception, this outcome indicates that subjective perceptual changes might inform us how to plan future actions. PMID:25504460

  7. Corrigendum: Exogenous Attention Enables Perceptual Learning.

    Science.gov (United States)

    2016-04-01

    Szpiro, S. F. A., & Carrasco, M. (2015). Exogenous attention enables perceptual learning.Psychological Science, 26, 1854-1862. (Original DOI:10.1177/0956797615598976)In the second paragraph of the Testing Sessions section of this article, thetvalue for the between-group difference in spatial-frequency differences was incorrectly reported as 9.49,p> .1, rather than 0.95,p> .1. The sentence should read as follows:There was no significant difference between groups for the orientation differences,t(12) = 1.51,p> .1, or for the spatial-frequency differences,t(12) = 0.95,p> .1.Thus, the conclusion regarding the lack of significance remains the same. PMID:26935483

  8. What is the Bandwidth of Perceptual Experience?

    Science.gov (United States)

    Cohen, Michael A; Dennett, Daniel C; Kanwisher, Nancy

    2016-05-01

    Although our subjective impression is of a richly detailed visual world, numerous empirical results suggest that the amount of visual information observers can perceive and remember at any given moment is limited. How can our subjective impressions be reconciled with these objective observations? Here, we answer this question by arguing that, although we see more than the handful of objects, claimed by prominent models of visual attention and working memory, we still see far less than we think we do. Taken together, we argue that these considerations resolve the apparent conflict between our subjective impressions and empirical data on visual capacity, while also illuminating the nature of the representations underlying perceptual experience. PMID:27105668

  9. Asymmetric transfer of auditory perceptual learning

    Directory of Open Access Journals (Sweden)

    SygalAmitay

    2012-11-01

    Full Text Available Perceptual skills can improve dramatically even with minimal practice. A major and practical benefit of learning, however, is in transferring the improvement on the trained task to untrained tasks or stimuli, yet the mechanisms underlying this process are still poorly understood. Reduction of internal noise has been proposed as a mechanism of perceptual learning, and while we have evidence that frequency discrimination (FD learning is due to a reduction of internal noise, the source of that noise was not determined. In this study, we examined whether reducing the noise associated with neural phase locking to tones can explain the observed improvement in behavioural thresholds. We compared FD training between two tone durations (15 and 100 ms that straddled the temporal integration window of auditory nerve fibers upon which computational modeling of phase locking noise was based. Training on short tones resulted in improved FD on probe tests of both the long and short tones. Training on long tones resulted in improvement only on the long tones. Simulations of FD learning, based on the computational model and on signal detection theory, were compared with the behavioral FD data. We found that improved fidelity of phase locking accurately predicted transfer of learning from short to long tones, but also predicted transfer from long to short tones. The observed lack of transfer from long to short tones suggests the involvement of a second mechanism. Training may have increased the temporal integration window which could not transfer because integration time for the short tone is limited by its duration. Current learning models assume complex relationships between neural populations that represent the trained stimuli. In contrast, we propose that training-induced enhancement of the signal-to-noise ratio offers a parsimonious explanation of learning and transfer that easily accounts for asymmetric transfer of learning.

  10. Strictness Analysis for Attribute Grammars

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    1992-01-01

    Attribute grammars may be seen as a (rather specialised) lazy or demand-driven programming language. The ``programs'' in this language take text or parse trees as input and return values of the synthesised attributes to the root as output. From this observation we establish a framework for abstract...... interpretation of attribute grammars. The framework is used to construct a strictness analysis for attribute grammars. Results of the analysis enable us to transform an attribute grammar such that attributes are evaluated during parsing, if possible. The analysis is proved correct by relating it to a fixpoint...... semantics for attribute grammars. An implementation of the analysis is discussed and some extensions to the analysis are mentioned....

  11. Mining Attribute-structure Correlated Patterns in Large Attributed Graphs

    CERN Document Server

    Silva, Arlei; Zaki, Mohammed J

    2012-01-01

    In this work, we study the correlation between attribute sets and the occurrence of dense subgraphs in large attributed graphs, a task we call structural correlation pattern mining. A structural correlation pattern is a dense subgraph induced by a particular attribute set. Existing methods are not able to extract relevant knowledge regarding how vertex attributes interact with dense subgraphs. Structural correlation pattern mining combines aspects of frequent itemset and quasi-clique mining problems. We propose statistical significance measures that compare the structural correlation of attribute sets against their expected values using null models. Moreover, we evaluate the interestingness of structural correlation patterns in terms of size and density. An efficient algorithm that combines search and pruning strategies in the identification of the most relevant structural correlation patterns is presented. We apply our method for the analysis of three real-world attributed graphs: a collaboration, a music, a...

  12. Individual differences in attention influence perceptual decision making

    Directory of Open Access Journals (Sweden)

    Michael Dawson Nunez

    2015-02-01

    Full Text Available Sequential sampling decision-making models have been successful in accounting for reactiontime (RT and accuracy data in two-alternative forced choice tasks. These models have beenused to describe the behavior of populations of participants, and explanatory structures havebeen proposed to account for between individual variability in model parameters. In this studywe show that individual differences in behavior from a novel perceptual decision making taskcan be attributed to 1 differences in evidence accumulation rates, 2 differences in variability ofevidence accumulation within trials, and 3 differences in non-decision times across individuals.Using electroencephalography (EEG, we demonstrate that these differences in cognitivevariables, in turn, can be explained by attentional differences as measured by phase-lockingof steady-state visual evoked potential (SSVEP responses to the signal and noise componentsof the visual stimulus. Parameters of a cognitive model (a diffusion model were obtained fromaccuracy and RT distributions and related to phase-locking indices (PLIs of SSVEPs with asingle step in a hierarchical Bayesian framework. Participants who were able to suppress theSSVEP response to visual noise in high frequency bands were able to accumulate correctevidence faster and had shorter non-decision times (preprocessing or motor response times,leading to more accurate responses and faster response times. We show that the combinationof cognitive modeling and neural data in a hierarchical Bayesian framework relates physiologicalprocesses to the cognitive processes of participants, and that a model with a new (out-of-sample participant’s neural data can predict that participant’s behavior more accurately thanmodels without physiological data.

  13. Development of a perceptually calibrated objective metric of noise

    Science.gov (United States)

    Keelan, Brian W.; Jin, Elaine W.; Prokushkin, Sergey

    2011-01-01

    A system simulation model was used to create scene-dependent noise masks that reflect current performance of mobile phone cameras. Stimuli with different overall magnitudes of noise and with varying mixtures of red, green, blue, and luminance noises were included in the study. Eleven treatments in each of ten pictorial scenes were evaluated by twenty observers using the softcopy ruler method. In addition to determining the quality loss function in just noticeable differences (JNDs) for the average observer and scene, transformations for different combinations of observer sensitivity and scene susceptibility were derived. The psychophysical results were used to optimize an objective metric of isotropic noise based on system noise power spectra (NPS), which were integrated over a visual frequency weighting function to yield perceptually relevant variances and covariances in CIE L*a*b* space. Because the frequency weighting function is expressed in terms of cycles per degree at the retina, it accounts for display pixel size and viewing distance effects, so application-specific predictions can be made. Excellent results were obtained using only L* and a* variances and L*a* covariance, with relative weights of 100, 5, and 12, respectively. The positive a* weight suggests that the luminance (photopic) weighting is slightly narrow on the long wavelength side for predicting perceived noisiness. The L*a* covariance term, which is normally negative, reflects masking between L* and a* noise, as confirmed in informal evaluations. Test targets in linear sRGB and rendered L*a*b* spaces for each treatment are available at http://www.aptina.com/ImArch/ to enable other researchers to test metrics of their own design and calibrate them to JNDs of quality loss without performing additional observer experiments. Such JND-calibrated noise metrics are particularly valuable for comparing the impact of noise and other attributes, and for computing overall image quality.

  14. Perceptual learning in Williams syndrome: looking beyond averages.

    Directory of Open Access Journals (Sweden)

    Patricia Gervan

    Full Text Available Williams Syndrome is a genetically determined neurodevelopmental disorder characterized by an uneven cognitive profile and surprisingly large neurobehavioral differences among individuals. Previous studies have already shown different forms of memory deficiencies and learning difficulties in WS. Here we studied the capacity of WS subjects to improve their performance in a basic visual task. We employed a contour integration paradigm that addresses occipital visual function, and analyzed the initial (i.e. baseline and after-learning performance of WS individuals. Instead of pooling the very inhomogeneous results of WS subjects together, we evaluated individual performance by expressing it in terms of the deviation from the average performance of the group of typically developing subjects of similar age. This approach helped us to reveal information about the possible origins of poor performance of WS subjects in contour integration. Although the majority of WS individuals showed both reduced baseline and reduced learning performance, individual analysis also revealed a dissociation between baseline and learning capacity in several WS subjects. In spite of impaired initial contour integration performance, some WS individuals presented learning capacity comparable to learning in the typically developing population, and vice versa, poor learning was also observed in subjects with high initial performance levels. These data indicate a dissociation between factors determining initial performance and perceptual learning.

  15. Perceptual Learning in Williams Syndrome: Looking Beyond Averages

    Science.gov (United States)

    Gervan, Patricia; Gombos, Ferenc; Kovacs, Ilona

    2012-01-01

    Williams Syndrome is a genetically determined neurodevelopmental disorder characterized by an uneven cognitive profile and surprisingly large neurobehavioral differences among individuals. Previous studies have already shown different forms of memory deficiencies and learning difficulties in WS. Here we studied the capacity of WS subjects to improve their performance in a basic visual task. We employed a contour integration paradigm that addresses occipital visual function, and analyzed the initial (i.e. baseline) and after-learning performance of WS individuals. Instead of pooling the very inhomogeneous results of WS subjects together, we evaluated individual performance by expressing it in terms of the deviation from the average performance of the group of typically developing subjects of similar age. This approach helped us to reveal information about the possible origins of poor performance of WS subjects in contour integration. Although the majority of WS individuals showed both reduced baseline and reduced learning performance, individual analysis also revealed a dissociation between baseline and learning capacity in several WS subjects. In spite of impaired initial contour integration performance, some WS individuals presented learning capacity comparable to learning in the typically developing population, and vice versa, poor learning was also observed in subjects with high initial performance levels. These data indicate a dissociation between factors determining initial performance and perceptual learning. PMID:22792262

  16. [Mother's attributions regarding children's behavior and maltreatment].

    Science.gov (United States)

    Nakaya, Namiko

    2016-04-01

    This study aimed to compare maltreating mothers and non-maltreating mothers on attributions and affects related to child behaviors. It also assessed how attributions predict affective and behavioral reactions to child behaviors. The study population comprised of a community-based sample of mothers with children aged 2 to 4 years (n = 238). Mothers' attributions and affect were assessed using vignettes of child behavior. They also answered questions about their maltreating parenting behaviors and demographic factors such as childcare environments. Results highlighted that, as compared with non-maltreating mothers, maltreating mothers made more intentional and stable attributions to negative child behavior, and to report more anger and aversion. They also had a tendency to report less happiness toward positive child behavior. Additionally, path analyses documented a pattern of thinking-feeling-action linkages. It was revealed that attributions regarding children's behavior influenced negative affect and that negative affect in turn predicted maltreatment. Finally, the usefulness of a cognitive approach to maltreating mothers, and the implications of the findings as a model for intervention are discussed. PMID:27180512

  17. Elicitation of attributes for the evaluation of audio-on audio-interference

    DEFF Research Database (Denmark)

    Francombe, Jon; Mason, R.; Dewhirst, M.;

    2014-01-01

    An experiment to determine the perceptual attributes of the experience of listening to a target audio program in the presence of an audio interferer was performed. The first stage was a free elicitation task in which a total of 572 phrases were produced. In the second stage, a consensus vocabulary......, annoyance, balance and blend, and confusion. Ratings using these attributes were collected in the fourth stage, and a principal component analysis performed. This suggested two dimensions underlying the perception of an audio-on-audio interference situation: The first dimension was labeled “distraction” and...

  18. Relationship between aggressive and interpersonal attribution among students aged nine to twelve%小学高年级学生攻击行为与人际归因关系

    Institute of Scientific and Technical Information of China (English)

    杨奕; 余毅震; 孙艳; 罗贻雪

    2011-01-01

    Objective To explore the factors which influence the students' aggressive behaviors and the features of interpersonal attribution of students, and the relationship between aggressive behaviors and interpersonal attribution, then to provide the foundation for the prevention of aggression. Methods A stratified random cluster sample of 7 008 pupils in urban China were asked to complete the Buss-Warren Aggression Questionnaire and The Multidimentional-Multiattributional Causality Scale. Results The students whose father with a higher educational background ( P<0.05) had lower aggression score, and the students who had strict discipline and higher anticipation from parent ( P<0.001 ) get lower aggression score. The result showed that the students who had good relationship with their teachers and friends had lower score( P<0.001 ). The students who lived in a better social conduct had weak aggressive behaviors( P<0. 001 ). Third, there was an obvious correlation of the outer control of interpersonal attribution with aggressive behaviors ( r=0.4, P<0. 01 ), and the more extroversion in interpersonal attribution, the stronger aggression in behavior. Conclusion Im prove the situation of family, school and society, and help students recognize themselves and improve the relationship with others can better prevent and intervene the aggression of students.%目的 探讨小学生攻击行为与人际归因的关系,对预防攻击行为提供依据.方法 采用多阶段分层整群抽样方法,在安徽、云南、广东、黑龙江、湖北等5省15个大、中、小城市抽取7008名小学生进行攻击行为问卷和人际归因策略调查.结果 父亲文化程度高(P<0.05)、父母管教方式严格、对孩子期望值高(P<0.001)的学生攻击性低;与老师和同学有较好的关系、成绩优良、居住地社会风气较好(P<0.001)的学生攻击得分明显低于其他学生;人际关系外倾性归因与攻击行为有显著相关(r=0.4,P<0.01),

  19. Causal evidence for frontal cortex organization for perceptual decision making.

    Science.gov (United States)

    Rahnev, Dobromir; Nee, Derek Evan; Riddle, Justin; Larson, Alina Sue; D'Esposito, Mark

    2016-05-24

    Although recent research has shown that the frontal cortex has a critical role in perceptual decision making, an overarching theory of frontal functional organization for perception has yet to emerge. Perceptual decision making is temporally organized such that it requires the processes of selection, criterion setting, and evaluation. We hypothesized that exploring this temporal structure would reveal a large-scale frontal organization for perception. A causal intervention with transcranial magnetic stimulation revealed clear specialization along the rostrocaudal axis such that the control of successive stages of perceptual decision making was selectively affected by perturbation of successively rostral areas. Simulations with a dynamic model of decision making suggested distinct computational contributions of each region. Finally, the emergent frontal gradient was further corroborated by functional MRI. These causal results provide an organizational principle for the role of frontal cortex in the control of perceptual decision making and suggest specific mechanistic contributions for its different subregions. PMID:27162349

  20. Role and Development of Perceptual Skills in Medical Education

    OpenAIRE

    Jarodzka, Halszka; Balslev, Thomas; Holmqvist, Kenneth; Nyström, Marcus; Scheiter, Katharina; Gerjets, Peter; Eika, Berit

    2011-01-01

    Jarodzka, H., Balslev, T., Holmqvist, K., Nyström, M., Scheiter, K., Gerjets, P., & Eika, B. (2010, May). Role and Development of Perceptual Skills in Medical Education. The Scandinavian Workshop on Applied Eye-Tracking (SWAET), Lund, Sweden.

  1. Perceptual task induces saccadic adaptation by target selection

    Directory of Open Access Journals (Sweden)

    Alexander Christian Schütz

    2015-10-01

    We replicated our finding that a perceptual task can drive adaptation of saccades. Adaptation showed no effect of feedback reliability, nor an effect of the perceptual task beyond target selection. Adaptation was induced by a top-down signal since it was absent when there was no target selection instruction and no perceptual task. The immediate error correction was larger for the difficult than for the easy condition, suggesting that task difficulty affects mainly voluntary saccade targeting. In addition, the repetition of experiments one week later increased the magnitude of the gradual error correction. The results dissociate two distinct components of adaptation: an immediate and a gradual error correction. We conclude that perceptual-task induced adaptation is most likely due to top-down target selection within a larger object.

  2. Perceptual representations in false recognition and priming of pictures.

    Science.gov (United States)

    Weinstein, Yana; Shanks, David R

    2008-12-01

    Using a new procedure, we investigate whether imagination can induce false memory by creating a perceptual representation. Participants studied pictures and words with and without an imagery task and at test performed both a direct recognition test and an indirect perceptual identification test on pictorial stimuli. Corrected false recognition rates were 7% for pictures studied in word form (Experiment 1), 26% for pictures imagined once (Experiment 2), and 48% for pictures imagined multiple times (Experiment 3), although on the indirect test, no priming was found for these items. Furthermore, a perceptual/conceptual imagery manipulation did not affect the tendency to claim that imagined items had been studied as pictures (Experiment 4). These results suggest that the false memories reported on direct tests are not driven by perceptual representations. PMID:19015501

  3. Perceptual advertisement by the prey of stalking or ambushing predators

    OpenAIRE

    Broom, M.; Ruxton, G.D

    2012-01-01

    There has been previous theoretical explorations of the stability of signals by prey that they have detected a stalking or ambush predator, where such perceptual advertisement dissuades the predator from attacking. Here we use a game theoretical model to extend the theory to consider some empirically-motivated complexities: (i) many perceptual advertisement signals appear to have the potential to vary in intensity, (ii) higher intensity signals are likely to be most costly to produce, and (ii...

  4. Bayesian natural selection and the evolution of perceptual systems.

    OpenAIRE

    Geisler, Wilson S.; Diehl, Randy L.

    2002-01-01

    In recent years, there has been much interest in characterizing statistical properties of natural stimuli in order to better understand the design of perceptual systems. A fruitful approach has been to compare the processing of natural stimuli in real perceptual systems with that of ideal observers derived within the framework of Bayesian statistical decision theory. While this form of optimization theory has provided a deeper understanding of the information contained in natural stimuli as w...

  5. Neurological Evidence Linguistic Processes Precede Perceptual Simulation in Conceptual Processing

    OpenAIRE

    MaxLouwerse

    2012-01-01

    There is increasing evidence from response time experiments that language statistics and perceptual simulations both play a role in conceptual processing. In an EEG experiment we compared neural activity in cortical regions commonly associated with linguistic processing and visual perceptual processing to determine to what extent symbolic and embodied accounts of cognition applied. Participants were asked to determine the semantic relationship of word pairs (e.g., sky – ground) or to determin...

  6. The rapid emergence of stimulus specific perceptual learning

    OpenAIRE

    ZahraHussain; AllisonBSekuler

    2012-01-01

    Is stimulus specific perceptual learning the result of extended practice or does it emerge early in the time course of learning? We examined this issue by manipulating the amount of practice given on a face identification task on Day 1, and altering the familiarity of stimuli on Day 2. We found that a small number of trials was sufficient to produce stimulus specific perceptual learning of faces: on Day 2, response accuracy decreased by the same amount for novel stimuli regardless of whether ...

  7. High Resolution, High Capacity, Spatial Specificity in Perceptual Learning

    OpenAIRE

    Le Dantec, Christophe C.; Seitz, Aaron R.

    2012-01-01

    Research of perceptual learning has received significant interest due to findings that training on perceptual tasks can yield learning effects that are specific to the stimulus features of that task. However, recent studies have demonstrated that while training a single stimulus at a single location can yield a high-degree of stimulus specificity, training multiple features, or at multiple locations can reveal a broad transfer of learning to untrained features or stimulus locations. We devise...

  8. Perceptual Learning in the Absence of Task or Stimulus Specificity

    OpenAIRE

    Webb, Ben S.; Neil W. Roach; McGraw, Paul V.

    2007-01-01

    Performance on most sensory tasks improves with practice. When making particularly challenging sensory judgments, perceptual improvements in performance are tightly coupled to the trained task and stimulus configuration. The form of this specificity is believed to provide a strong indication of which neurons are solving the task or encoding the learned stimulus. Here we systematically decouple task- and stimulus-mediated components of trained improvements in perceptual performance and show th...

  9. Generating Images with Perceptual Similarity Metrics based on Deep Networks

    OpenAIRE

    Dosovitskiy, Alexey; Brox, Thomas

    2016-01-01

    Image-generating machine learning models are typically trained with loss functions based on distance in the image space. This often leads to over-smoothed results. We propose a class of loss functions, which we call deep perceptual similarity metrics (DeePSiM), that mitigate this problem. Instead of computing distances in the image space, we compute distances between image features extracted by deep neural networks. This metric better reflects perceptually similarity of images and thus leads ...

  10. Rapid Perceptual Switching of a Reversible Biological Figure

    OpenAIRE

    Stuart Jackson; Fred Cummins; Nuala Brady

    2008-01-01

    Certain visual stimuli can give rise to contradictory perceptions. In this paper we examine the temporal dynamics of perceptual reversals experienced with biological motion, comparing these dynamics to those observed with other ambiguous structure from motion (SFM) stimuli. In our first experiment, naïve observers monitored perceptual alternations with an ambiguous rotating walker, a figure that randomly alternates between walking in clockwise (CW) and counter-clockwise (CCW) directions. Whil...

  11. Learning to perceptually organize speech signals in native fashion1

    OpenAIRE

    Nittrouer, Susan; Lowenstein, Joanna H.

    2010-01-01

    The ability to recognize speech involves sensory, perceptual, and cognitive processes. For much of the history of speech perception research, investigators have focused on the first and third of these, asking how much and what kinds of sensory information are used by normal and impaired listeners, as well as how effective amounts of that information are altered by “top-down” cognitive processes. This experiment focused on perceptual processes, asking what accounts for how the sensory informat...

  12. A Chance for Attributable Agency

    OpenAIRE

    Briegel, Hans J.; Müller, Thomas

    2015-01-01

    Can we sensibly attribute some of the happenings in our world to the agency of some of the things around us? We do this all the time, but there are conceptual challenges purporting to show that attributable agency, and specifically one of its most important subspecies, human free agency, is incoherent. We address these challenges in a novel way: rather than merely rebutting specific arguments, we discuss a concrete model that we claim positively illustrates attributable agency in an indetermi...

  13. Testing performance of CIECAM02 in predicting perceptual contrast

    Institute of Scientific and Technical Information of China (English)

    Weige Lü; Haisong Xu; M.Ronnier Luo

    2012-01-01

    A psychophysical experiment is performed on two large-size liquid crystal displays under three viewing conditions to assess perceptual contrast.Based on the visual data,the performance of CIECAM02 in predicting perceptual contrast under different viewing conditions is tested and compared with other models by F-test.Results show that the perceptual contrast models in the form of Weber contrast using CIECAM02 brightness Q agreed better with the contrast perception of human visual system compared to the models using luminance,CIELAB lightness L*,and CIECAM02 lightness J.%A psychophysical experiment is performed on two large-size liquid crystal displays under three viewing conditions to assess perceptual contrast. Based on the visual data, the performance of CIECAM02 in predicting perceptual contrast under different viewing conditions is tested and compared with other models by F-test. Results show that the perceptual contrast models in the form of Weber contrast using CIECAM02 brightness Q agreed better with the contrast perception of human visual system compared to the models using luminance, CIELAB lightness U, and CIECAM02 lightness J.

  14. Perceptual Load Affects Eyewitness Accuracy and Susceptibility to Leading Questions.

    Science.gov (United States)

    Murphy, Gillian; Greene, Ciara M

    2016-01-01

    Load Theory (Lavie, 1995, 2005) states that the level of perceptual load in a task (i.e., the amount of information involved in processing task-relevant stimuli) determines the efficiency of selective attention. There is evidence that perceptual load affects distractor processing, with increased inattentional blindness under high load. Given that high load can result in individuals failing to report seeing obvious objects, it is conceivable that load may also impair memory for the scene. The current study is the first to assess the effect of perceptual load on eyewitness memory. Across three experiments (two video-based and one in a driving simulator), the effect of perceptual load on eyewitness memory was assessed. The results showed that eyewitnesses were less accurate under high load, in particular for peripheral details. For example, memory for the central character in the video was not affected by load but memory for a witness who passed by the window at the edge of the scene was significantly worse under high load. High load memories were also more open to suggestion, showing increased susceptibility to leading questions. High visual perceptual load also affected recall for auditory information, illustrating a possible cross-modal perceptual load effect on memory accuracy. These results have implications for eyewitness memory researchers and forensic professionals. PMID:27625628

  15. Perceptual Object Extraction Based on Saliency and Clustering

    Directory of Open Access Journals (Sweden)

    Qiaorong Zhang

    2010-08-01

    Full Text Available Object-based visual attention has received an increasing interest in recent years. Perceptual object is the basic attention unit of object-based visual attention. The definition and extraction of perceptual objects is one of the key technologies in object-based visual attention computation model. A novel perceptual object definition and extraction method is proposed in this paper. Based on Gestalt theory and visual feature integration theory, perceptual object is defined using homogeneity region, salient region and edges. An improved saliency map generating algorithm is employed first. Based on the saliency map, salient edges are extracted. Then graph-based clustering algorithm is introduced to get homogeneity regions in the image. Finally an integration strategy is adopted to combine salient edges and homogeneity regions to extract perceptual objects. The proposed perceptual object extraction method has been tested on lots of natural images. Experiment results and analysis are presented in this paper also. Experiment results show that the proposed method is reasonable and valid.

  16. Perceptual guidelines for creating rectangular treemaps.

    Science.gov (United States)

    Kong, Nicholas; Heer, Jeffrey; Agrawala, Maneesh

    2010-01-01

    Treemaps are space-filling visualizations that make efficient use of limited display space to depict large amounts of hierarchical data. Creating perceptually effective treemaps requires carefully managing a number of design parameters including the aspect ratio and luminance of rectangles. Moreover, treemaps encode values using area, which has been found to be less accurate than judgments of other visual encodings, such as length. We conduct a series of controlled experiments aimed at producing a set of design guidelines for creating effective rectangular treemaps. We find no evidence that luminance affects area judgments, but observe that aspect ratio does have an effect. Specifically, we find that the accuracy of area comparisons suffers when the compared rectangles have extreme aspect ratios or when both are squares. Contrary to common assumptions, the optimal distribution of rectangle aspect ratios within a treemap should include non-squares, but should avoid extremes. We then compare treemaps with hierarchical bar chart displays to identify the data densities at which length-encoded bar charts become less effective than area-encoded treemaps. We report the transition points at which treemaps exhibit judgment accuracy on par with bar charts for both leaf and non-leaf tree nodes. We also find that even at relatively low data densities treemaps result in faster comparisons than bar charts. Based on these results, we present a set of guidelines for the effective use of treemaps and suggest alternate approaches for treemap layout. PMID:20975136

  17. Neuroticism as distancing: perceptual sources of evidence.

    Science.gov (United States)

    Liu, Tianwei; Ode, Scott; Moeller, Sara K; Robinson, Michael D

    2013-05-01

    Several theories and self-reported sources of data link individual differences in negative affectivity to avoidance motivation. Chronic avoidance motivation, through repeated practice, may result in a relatively cognitive distance-enhancing dynamic whereby events and stimuli are perceived as further away from the self, even when they are not threatening. Such predictions are novel but follow from cybernetic theories of self-regulation. In 5 studies (total N = 463), relations of this type were investigated. Study 1 presented participants with phrases that were ambiguous and found that trait negative affect predicted phrase interpretation in a distance-enhancing temporal direction. Study 2 replicated this effect across a systematic manipulation of event valence. Study 3 asked individuals to estimate the size of words and found that individuals higher in neuroticism generally perceived words to be smaller than did individuals lower in neuroticism. In Study 4, people high (but not low) in neuroticism perceived words to be shrinking faster than they were growing. In Study 5, greater perceptual distancing, in a font size estimation task, predicted more adverse reactions to negative events in daily life. Although normative effects varied across studies, consistent support for a chronic distancing perspective of individual differences in negative affectivity was found. PMID:23527850

  18. The perceptual and social components of metacognition.

    Science.gov (United States)

    Pescetelli, Niccolo; Rees, Geraint; Bahrami, Bahador

    2016-08-01

    When deciding whether or not to bring an umbrella to work, your confidence will be influenced by the sky outside the window (direct evidence) as well as by, for example, whether or not people walking in the street have their own umbrella (indirect or contingent evidence). These 2 distinct aspects of decision confidence have not yet been assessed independently within the same framework. Here we study the relative contributions of stimulus-specific and social-contingent information on confidence formation. Dyads of participants made visual perceptual decisions, first individually and then together by sharing their wagers in their decisions. We independently manipulated the sensory evidence and the social consensus available to participants and found that both type of evidence contributed to wagers. Consistent with previous work, the amount people were prepared to wager covaried with the strength of sensory evidence. However, social agreements and disagreement affected wagers in opposite directions and asymmetrically. These different contributions of sensory and social evidence to wager were linearly additive. Moreover, average metacognitive sensitivity-namely the association between wagers and accuracy-between interacting dyad members positively correlated with dyadic performance and dyadic benefit above average individual performance. Our results provide a general framework that accounts for how both social context and direct sensory evidence contribute to decision confidence. (PsycINFO Database Record PMID:27454040

  19. Anger perceptually and conceptually narrows cognitive scope.

    Science.gov (United States)

    Gable, Philip A; Poole, Bryan D; Harmon-Jones, Eddie

    2015-07-01

    For the last 50 years, research investigating the effect of emotions on scope of cognitive processing was based on models proposing that affective valence determined cognitive scope. More recently, our motivational intensity model suggests that this past work had confounded valence with motivational intensity. Research derived from this model supports the idea that motivational intensity, rather than affective valence, explains much of the variance emotions have on cognitive scope. However, the motivational intensity model is limited in that the empirical work has examined only positive affects high in approach and negative affects high in avoidance motivation. Thus, perhaps only approach-positive and avoidance-negative states narrow cognitive scope. The present research was designed to clarify these conceptual issues by examining the effect of anger, a negatively valenced approach-motivated state, on cognitive scope. Results revealed that anger narrowed attentional scope relative to a neutral state and that attentional narrowing to anger was similar to the attentional narrowing caused by high approach-motivated positive affects (Study 1). This narrowing of attention was related to trait approach motivation (Studies 2 and Study 3). Anger also narrowed conceptual cognitive categorization (Study 4). Narrowing of categorization related to participants' approach motivation toward anger stimuli. Together, these results suggest that anger, an approach-motivated negative affect, narrows perceptual and conceptual cognitive scope. More broadly, these results support the conceptual model that motivational intensity per se, rather than approach-positive and avoidance-negative states, causes a narrowing of cognitive scope. PMID:26011662

  20. Perceptual compensation for differences in speaking style.

    Science.gov (United States)

    Vitela, A Davi; Warner, Natasha; Lotto, Andrew J

    2013-01-01

    It is well-established that listeners will shift their categorization of a target vowel as a function of acoustic characteristics of a preceding carrier phrase (CP). These results have been interpreted as an example of perceptual normalization for variability resulting from differences in talker anatomy. The present study examined whether listeners would normalize for acoustic variability resulting from differences in speaking style within a single talker. Two vowel series were synthesized that varied between central and peripheral vowels (the vowels in "beat"-"bit" and "bod"-"bud"). Each member of the series was appended to one of four CPs that were spoken in either a "clear" or "reduced" speech style. Participants categorized vowels in these eight contexts. A reliable shift in categorization as a function of speaking style was obtained for three of four phrase sets. This demonstrates that phrase context effects can be obtained with a single talker. However, the directions of the obtained shifts are not reliably predicted on the basis of the speaking style of the talker. Instead, it appears that the effect is determined by an interaction of the average spectrum of the phrase with the target vowel. PMID:23847573

  1. Perceptual compensation for differences in speaking style

    Directory of Open Access Journals (Sweden)

    A. Davi eVitela

    2013-07-01

    Full Text Available It is well-established that listeners will shift their categorization of a target vowel as a function of acoustic characteristics of a preceding carrier phrase. These results have been interpreted as an example of perceptual normalization for variability resulting from differences in talker anatomy. The present study examined whether listeners would normalize for acoustic variability resulting from differences in speaking style within a single talker. Two vowel series were synthesized that varied between central and peripheral vowels (the vowels in beat‐bit and bod‐bud. Each member of the series was appended to one of four carrier phrases that were spoken in either a clear or reduced speech style. Participants categorized vowels in these eight contexts. A reliable shift in categorization as a function of speaking style was obtained for three of four phrase sets. This demonstrates that phrase context effects can be obtained with a single talker. However, the directions of the obtained shifts are not reliably predicted on the basis of the speaking style of the talker. Instead, it appears that the effect is determined by an interaction of the average spectrum of the phrase with the target vowel.

  2. The Effect of Kettlebell Swing Load and Cadence on Physiological, Perceptual and Mechanical Variables

    OpenAIRE

    Duncan, Michael J.; Rosanna Gibbard; Leanne M. Raymond; Peter Mundy

    2015-01-01

    This study compared the physiological, perceptual and mechanical responses to kettlebell swings at different loads and swing speeds. Following familiarization 16 strength trained participants (10 males, six females, mean age ± SD = 23 ± 2.9) performed four trials: 2 min kettlebell swings with an 8 kg kettlebell at a fast cadence; 2 min kettlebell swings with an 8 kg kettlebell at a slow cadence; 4 min kettlebell swings with a 4 kg kettlebell at a fast cadence; 4 min kettlebell swings with a 4...

  3. Attributional Style and School Truancy.

    Science.gov (United States)

    Kee, Tony Tam Shui

    2001-01-01

    Argues that little research has been directed toward exploring cognitive variables that characterize students with poor school attendance. Presents the findings of a pilot study that compared a small sample of truants and non-truants on locus of control and attributional style. Finds that attributional style is a significant factor in explaining…

  4. Seeing other minds: attributed mental states influence perception.

    Science.gov (United States)

    Teufel, Christoph; Fletcher, Paul C; Davis, Greg

    2010-08-01

    A current consensus views social perception as a bottom-up process in which the human brain uses social signals to make inferences about another's mental state. Here we propose that, contrary to this model, even the most basic perceptual processing of a social stimulus and closely associated automatic responses are modulated by mental-state attribution. We suggest that social perception is subserved by an interactive bidirectional relationship between the neural mechanisms supporting basic sensory processing of social information and the theory-of-mind system. Consequently, processing of a social stimulus cannot be divorced from its representation in terms of mental states. This hypothesis has far-reaching implications for our understanding of both the healthy social brain and characteristic social failures in psychopathology. PMID:20576464

  5. Microstructural White Matter Properties Mediate the Association between APOE and Perceptual Speed in Very Old Persons without Dementia

    OpenAIRE

    Laukka, Erika J.; Lövdén, Martin; Kalpouzos, Grégoria; Papenberg, Goran; Keller, Lina; Graff, Caroline; Li, Tie-Qiang; Fratiglioni, Laura; Bäckman, Lars

    2015-01-01

    Background Reduced white matter integrity, as indicated by lower fractional anisotropy (FA) and higher mean diffusivity (MD), has been related to poorer perceptual speed (PS) performance. As the ε4 allele has been associated with lower white matter integrity in old age, this represents a potential mechanism through which APOE may affect PS. Objective To examine whether the association between APOE and PS is mediated by white matter microstructure in very old persons without dementia. Method P...

  6. Perceptual organization deficits in traumatic brain injury patients.

    Science.gov (United States)

    Costa, Thiago L; Zaninotto, Ana Luiza C; Benute, Gláucia G; De Lúcia, Mara C S; Paiva, Wellingson S; Wagemans, Johan; Boggio, Paulo S

    2015-11-01

    Traumatic brain injury (TBI) is a prevalent condition and there is limited visual perception research with this population. Here, we investigated perceptual organization changes in a rather homogeneous sample of closed head TBI outpatients with diffuse axonal injury only and no other known comorbidities. Patients had normal or corrected visual acuity. Perceptual organization was measured with the Leuven Perceptual Organization Screening Test (L-POST), a coherent motion task (CM) and the Leuven Embedded Figures Test (L-EFT). These tests were chosen to screen for deficits in different aspects of perceptual organization (L-POST), to evaluate local and global processing (L-EFT) and grouping in a dynamic set of stimuli (CM). TBI patients were significantly impaired compared to controls in all measures for both response time and accuracy, except for CM thresholds and object recognition subtests. The TBI group was similarly affected in all aspects of the L-EFT. TBI was also similarly affected in all perceptual factors of the L-POST. No significant correlations were found between scores and time post-injury, except for CM thresholds (rs=-0.74), which might explain the lack of group-level differences. The only score significantly correlated to IQ was L-EFT response time (rs=-0.67). These findings demonstrate that perceptual organization is diffusely affected in TBI and this effect has no substantial correlations with IQ. As many of the neuropsychological tests used to measure different cognitive functions involve some level of visual discrimination and perceptual organization demands, these results must be taken into account in the general neuropsychological evaluation of TBI patients. PMID:26455804

  7. Identifying Key Attributes for Protein Beverages.

    Science.gov (United States)

    Oltman, A E; Lopetcharat, K; Bastian, E; Drake, M A

    2015-06-01

    This study identified key attributes of protein beverages and evaluated effects of priming on liking of protein beverages. An adaptive choice-based conjoint study was conducted along with Kano analysis to gain insight on protein beverage consumers (n = 432). Attributes evaluated included label claim, protein type, amount of protein, carbohydrates, sweeteners, and metabolic benefits. Utility scores for levels and importance scores for attributes were determined. Subsequently, two pairs of clear acidic whey protein beverages were manufactured that differed by age of protein source or the amount of whey protein per serving. Beverages were evaluated by 151 consumers on two occasions with or without priming statements. One priming statement declared "great flavor," the other priming statement declared 20 g protein per serving. A two way analysis of variance was applied to discern the role of each priming statement. The most important attribute for protein beverages was sweetener type, followed by amount of protein, followed by type of protein followed by label claim. Beverages with whey protein, naturally sweetened, reduced sugar and ≥15 g protein per serving were most desired. Three consumer clusters were identified, differentiated by their preferences for protein type, sweetener and amount of protein. Priming statements positively impacted concept liking (P 0.05). Consistent with trained panel profiles of increased cardboard flavor with higher protein content, consumers liked beverages with 10 g protein more than beverages with 20 g protein (6.8 compared with 5.7, P consumer appeal. PMID:25943857

  8. Eye movements and the perceptual span during first- and second-language sentence reading in bilingual older adults.

    Science.gov (United States)

    Whitford, Veronica; Titone, Debra

    2016-02-01

    This study addressed a central yet previously unexplored issue in the psychological science of aging, namely, whether the advantages of healthy aging (e.g., greater lifelong experience with language) or disadvantages (e.g., decreases in cognitive and sensory processing) drive L1 and L2 reading performance in bilingual older adults. To this end, we used a gaze-contingent moving window paradigm to examine both global aspects of reading fluency (e.g., reading rates, number of regressions) and the perceptual span (i.e., allocation of visual attention into the parafovea) in bilingual older adults during L1 and L2 sentence reading, as a function of individual differences in current L2 experience. Across the L1 and L2, older adults exhibited reduced reading fluency (e.g., slower reading rates, more regressions), but a similar perceptual span compared with matched younger adults. Also similar to matched younger adults, older adults' reading fluency was lower for L2 reading than for L1 reading as a function of current L2 experience. Specifically, greater current L2 experience increased L2 reading fluency, but decreased L1 reading fluency (for global reading measures only). Taken together, the dissociation between intact perceptual span and impaired global reading measures suggests that older adults may prioritize parafoveal processing despite age-related encoding difficulties. Consistent with this interpretation, post hoc analyses revealed that older adults with higher versus lower executive control were more likely to adopt this strategy. PMID:26866589

  9. Attribute-Based Data Sharing

    Directory of Open Access Journals (Sweden)

    Ms. Rahila Fatima

    2014-12-01

    Full Text Available Messages addressed to specific users can be decrypted by Key Generation Centre (KGC by generating their private keys. Data owner wants the data to be delivered only to specified user and not to unauthorized person that is the data owner makes their private data accessible only to authorized person. We propose attribute based encryption and escrow problem which means written agreement delivered to a third party to overcome this problem. Attribute based Encryption (ABE is a type of public-key encryption in which the private key of a user and the cipher text are dependent upon attributes. It is a promising cryptographic approach.

  10. Neural adaptation in pSTS correlates with perceptual aftereffects to biological motion and with autistic traits.

    Science.gov (United States)

    Thurman, Steven M; van Boxtel, Jeroen J A; Monti, Martin M; Chiang, Jeffrey N; Lu, Hongjing

    2016-08-01

    The adaptive nature of biological motion perception has been documented in behavioral studies, with research showing that prolonged viewing of an action can bias judgments of subsequent actions towards the opposite of its attributes. However, the neural mechanisms underlying action adaptation aftereffects remain unknown. We examined adaptation-induced changes in brain responses to an ambiguous action after adapting to walking or running actions within two bilateral regions of interest: 1) human middle temporal area (hMT+), a lower-level motion-sensitive region of cortex, and 2) posterior superior temporal sulcus (pSTS), a higher-level action-selective area. We found a significant correlation between neural adaptation strength in right pSTS and perceptual aftereffects to biological motion measured behaviorally, but not in hMT+. The magnitude of neural adaptation in right pSTS was also strongly correlated with individual differences in the degree of autistic traits. Participants with more autistic traits exhibited less adaptation-induced modulations of brain responses in right pSTS and correspondingly weaker perceptual aftereffects. These results suggest a direct link between perceptual aftereffects and adaptation of neural populations in right pSTS after prolonged viewing of a biological motion stimulus, and highlight the potential importance of this brain region for understanding differences in social-cognitive processing along the autistic spectrum. PMID:27164327

  11. Neural mechanisms underlying the induction and relief of perceptual curiosity

    Directory of Open Access Journals (Sweden)

    Marieke Jepma

    2012-02-01

    Full Text Available Curiosity is one of the most basic biological drives in both animals and humans, and has been identified as a key motive for learning and discovery. Despite the importance of curiosity and related behaviors, the topic has been largely neglected in human neuroscience; hence little is known about the neurobiological mechanisms underlying curiosity. We used functional magnetic resonance imaging (fMRI to investigate what happens in our brain during the induction and subsequent relief of perceptual curiosity. Our core findings were that (i the induction of perceptual curiosity, through the presentation of ambiguous visual input, activated the anterior insula and anterior cingulate cortex, brain regions sensitive to conflict and arousal; (ii the relief of perceptual curiosity, through visual disambiguation, activated regions of the striatum that have been related to reward processing; and (iii the relief of perceptual curiosity was associated with hippocampal activation and enhanced incidental memory. These findings provide the first demonstration of the neural basis of human perceptual curiosity. Our results provide neurobiological support for a classic psychological theory of curiosity, which holds that curiosity is an aversive condition of increased arousal whose termination is rewarding and facilitates memory.

  12. Automated characterization of perceptual quality of clinical chest radiographs: Validation and calibration to observer preference

    International Nuclear Information System (INIS)

    Purpose: The authors previously proposed an image-based technique [Y. Lin et al. Med. Phys. 39, 7019–7031 (2012)] to assess the perceptual quality of clinical chest radiographs. In this study, an observer study was designed and conducted to validate the output of the program against rankings by expert radiologists and to establish the ranges of the output values that reflect the acceptable image appearance so the program output can be used for image quality optimization and tracking. Methods: Using an IRB-approved protocol, 2500 clinical chest radiographs (PA/AP) were collected from our clinical operation. The images were processed through our perceptual quality assessment program to measure their appearance in terms of ten metrics of perceptual image quality: lung gray level, lung detail, lung noise, rib–lung contrast, rib sharpness, mediastinum detail, mediastinum noise, mediastinum alignment, subdiaphragm–lung contrast, and subdiaphragm area. From the results, for each targeted appearance attribute/metric, 18 images were selected such that the images presented a relatively constant appearance with respect to all metrics except the targeted one. The images were then incorporated into a graphical user interface, which displayed them into three panels of six in a random order. Using a DICOM calibrated diagnostic display workstation and under low ambient lighting conditions, each of five participating attending chest radiologists was tasked to spatially order the images based only on the targeted appearance attribute regardless of the other qualities. Once ordered, the observer also indicated the range of image appearances that he/she considered clinically acceptable. The observer data were analyzed in terms of the correlations between the observer and algorithmic rankings and interobserver variability. An observer-averaged acceptable image appearance was also statistically derived for each quality attribute based on the collected individual acceptable ranges

  13. Automated characterization of perceptual quality of clinical chest radiographs: Validation and calibration to observer preference

    Energy Technology Data Exchange (ETDEWEB)

    Samei, Ehsan, E-mail: samei@duke.edu [Carl E. Ravin Advanced Imaging Laboratories, Departments of Radiology, Physics, Biomedical Engineering, Electrical and Computer Engineering, Medical Physics Graduate Program, Duke Clinical Imaging Physics Group, Duke University, Durham, North Carolina 27710 (United States); Lin, Yuan [Carl E. Ravin Advanced Imaging Laboratories, Departments of Radiology and Physics, Duke University, Durham, North Carolina 27710 (United States); Choudhury, Kingshuk R. [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology and Biostatistics and Bioinformatics, Duke University, Durham, North Carolina 27710 (United States); Page McAdams, H. [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, Durham, North Carolina 27710 (United States)

    2014-11-01

    Purpose: The authors previously proposed an image-based technique [Y. Lin et al. Med. Phys. 39, 7019–7031 (2012)] to assess the perceptual quality of clinical chest radiographs. In this study, an observer study was designed and conducted to validate the output of the program against rankings by expert radiologists and to establish the ranges of the output values that reflect the acceptable image appearance so the program output can be used for image quality optimization and tracking. Methods: Using an IRB-approved protocol, 2500 clinical chest radiographs (PA/AP) were collected from our clinical operation. The images were processed through our perceptual quality assessment program to measure their appearance in terms of ten metrics of perceptual image quality: lung gray level, lung detail, lung noise, rib–lung contrast, rib sharpness, mediastinum detail, mediastinum noise, mediastinum alignment, subdiaphragm–lung contrast, and subdiaphragm area. From the results, for each targeted appearance attribute/metric, 18 images were selected such that the images presented a relatively constant appearance with respect to all metrics except the targeted one. The images were then incorporated into a graphical user interface, which displayed them into three panels of six in a random order. Using a DICOM calibrated diagnostic display workstation and under low ambient lighting conditions, each of five participating attending chest radiologists was tasked to spatially order the images based only on the targeted appearance attribute regardless of the other qualities. Once ordered, the observer also indicated the range of image appearances that he/she considered clinically acceptable. The observer data were analyzed in terms of the correlations between the observer and algorithmic rankings and interobserver variability. An observer-averaged acceptable image appearance was also statistically derived for each quality attribute based on the collected individual acceptable ranges

  14. I "hear" what you're "saying": Auditory perceptual simulation, reading speed, and reading comprehension.

    Science.gov (United States)

    Zhou, Peiyun; Christianson, Kiel

    2016-05-01

    Auditory perceptual simulation (APS) during silent reading refers to situations in which the reader actively simulates the voice of a character or other person depicted in a text. In three eye-tracking experiments, APS effects were investigated as people read utterances attributed to a native English speaker, a non-native English speaker, or no speaker at all. APS effects were measured via online eye movements and offline comprehension probes. Results demonstrated that inducing APS during silent reading resulted in observable differences in reading speed when readers simulated the speech of faster compared to slower speakers and compared to silent reading without APS. Social attitude survey results indicated that readers' attitudes towards the native and non-native speech did not consistently influence APS-related effects. APS of both native speech and non-native speech increased reading speed, facilitated deeper, less good-enough sentence processing, and improved comprehension compared to normal silent reading. PMID:25679796

  15. Spanning Tree Based Attribute Clustering

    DEFF Research Database (Denmark)

    Zeng, Yifeng; Jorge, Cordero Hernandez

    2009-01-01

    inconsistent edges from a maximum spanning tree by starting appropriate initial modes, therefore generating stable clusters. It discovers sound clusters through simple graph operations and achieves significant computational savings. We compare the Star Discovery algorithm against earlier attribute clustering...

  16. Abstract Interpretation Using Attribute Grammar

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    1990-01-01

    This paper deals with the correctness proofs of attribute grammars using methods from abstract interpretation. The technique will be described by defining a live-variable analysis for a small flow-chart language and proving it correct with respect to a continuation style semantics. The proof...... technique is based on fixpoint induction and introduces an extended class of attribute grammars as to express a standard semantics....

  17. Direct Relationship Between Perceptual and Motor Variability

    Science.gov (United States)

    Liston, Dorion B.; Stone, Leland S.

    2010-01-01

    The time that elapses between stimulus onset and the onset of a saccadic eye movement is longer and more variable than can be explained by neural transmission times and synaptic delays (Carpenter, 1981, in: Eye Movements: Cognition & Visual Perception, Earlbaum). In theory, noise underlying response-time (RT) variability could arise at any point along the sensorimotor cascade, from sensory noise arising Vvithin the early visual processing shared Vvith perception to noise in the motor criterion or commands necessary to trigger movements. These two loci for internal noise can be distinguished empirically; sensory internal noise predicts that response time Vvill correlate Vvith perceived stimulus magnitude whereas motor internal noise predicts no such correlation. Methods. We used the data described by Liston and Stone (2008, JNS 28:13866-13875), in which subjects performed a 2AFC saccadic brightness discrimination task and the perceived brightness of the chosen stimulus was then quantified in a second 21FC perceptual task. Results. We binned each subject's data into quartiles for both signal strength (from dimmest to brightest) and RT (from slowest to fastest) and analyzed the trends in perceived brightness. We found significant effects of both signal strength (as expected) and RT on normalized perceived brightness (both p less than 0.0001, 2-way ANOVA), without significant interaction (p = 0.95, 2-way ANOVA). A plot of normalized perceived brightness versus normalized RT show's that more than half of the variance was shared (r2 = 0.56, P less than 0.0001). To rule out any possibility that some signal-strength related artifact was generating this effect, we ran a control analysis on pairs of trials with repeated presentations of identical stimuli and found that stimuli are perceived to be brighter on trials with faster saccades (p less than 0.001, paired t-test across subjects). Conclusion. These data show that shared early visual internal noise jitters perceived

  18. Language, Perceptual Categories and their Interaction: Insights from Computational Modelling

    Science.gov (United States)

    Belpaeme, Tony; Bleys, Joris

    How do humans acquire perceptual categories? This question is far from being resolved. Specifically the balance between the influence of nature and nurture on perceptual categories remains the topic of heated debate. We present a computational model and take as case study colour categories to study two issues in perceptual category acquisition. The first issue is the effect of linguistic communication on categories during their acquisition: we demonstrate how categories can become coordinated under the influence of language. The second issue concerns the amount of coordination needed between the categories of individuals in order to achieve unambiguous communication. We show that, depending on how strictly linguistic utterances are interpreted, coordination of the individuals' categories is not always a prerequisite for successful communication.

  19. Perceptual learning modifies the functional specializations of visual cortical areas.

    Science.gov (United States)

    Chen, Nihong; Cai, Peng; Zhou, Tiangang; Thompson, Benjamin; Fang, Fang

    2016-05-17

    Training can improve performance of perceptual tasks. This phenomenon, known as perceptual learning, is strongest for the trained task and stimulus, leading to a widely accepted assumption that the associated neuronal plasticity is restricted to brain circuits that mediate performance of the trained task. Nevertheless, learning does transfer to other tasks and stimuli, implying the presence of more widespread plasticity. Here, we trained human subjects to discriminate the direction of coherent motion stimuli. The behavioral learning effect substantially transferred to noisy motion stimuli. We used transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms underlying the transfer of learning. The TMS experiment revealed dissociable, causal contributions of V3A (one of the visual areas in the extrastriate visual cortex) and MT+ (middle temporal/medial superior temporal cortex) to coherent and noisy motion processing. Surprisingly, the contribution of MT+ to noisy motion processing was replaced by V3A after perceptual training. The fMRI experiment complemented and corroborated the TMS finding. Multivariate pattern analysis showed that, before training, among visual cortical areas, coherent and noisy motion was decoded most accurately in V3A and MT+, respectively. After training, both kinds of motion were decoded most accurately in V3A. Our findings demonstrate that the effects of perceptual learning extend far beyond the retuning of specific neural populations for the trained stimuli. Learning could dramatically modify the inherent functional specializations of visual cortical areas and dynamically reweight their contributions to perceptual decisions based on their representational qualities. These neural changes might serve as the neural substrate for the transfer of perceptual learning. PMID:27051066

  20. 周边视觉的知觉学习%Perceptual Learning of Peripheral Vision

    Institute of Scientific and Technical Information of China (English)

    徐笑含; 谢新秀; 邵志芳

    2012-01-01

    知觉学习是指知觉能力随着知觉训练或经验逐渐改变的现象。它具有特异性-迁移性,可以根据时程划分为快速学习和慢速学习。知觉学习意味着与知觉直接对应的脑区神经元激活方式的变化,并且与注意有着一定的联系。目前周边视觉的知觉学习研究已有一些成果:对于非语词刺激,随着练习,判断目标刺激(例如刺激朝向、游标视敏度)的能力,有很大的提升;对于语词刺激,周边视觉的知觉学习可以帮助提高阅读速度。可以通过提高视觉广度来提高周边视觉的阅读速度。周边视觉的知觉学习还有着重大应用价值,可以帮助中央凹视觉缺损的人们提高周边视觉能力,帮助恢复阅读能力。%Perceptual learning is defined as the improvement of the performance on perceptual tasks after training. Perceptual learning of human visual system has been widely investigated. Previous studies on perceptual learning were focused on its specificity and generalization. In some visual tasks, such as retinal location, spatial frequency or orientation, the learned performance is limited to the specific stimulus. In other visual tasks, the improved performance can be transferred to different stimuli or tasks. Specificity and generalization can be viewed as two the ends of a transferability continuum, on which each task may have a specific position (or value). Neurophysiological findings suggest that perceptual learning of different complexities may involve different levels of visual cortical processing, and the neural mechanism involved may depend on the feature ( e. g. , the complexity) of the stimulus in the task. Perceptual learning can be divided into fast learning and slow learning. A number of studies have used ERP and other brain imaging techniques to investigate the neural mechanism of visual perceptual learning under different time scales. Age-related macular degeneration (AMD) afflicts

  1. Exploration and Navigation for Mobile Robots With Perceptual Limitations

    OpenAIRE

    Morales, Eduardo F.; L. Enrique Sucar; Leonardo Romero

    2008-01-01

    To learn a map of an environment a mobile robot has to explore its workspace using its sensors. Sensors are noisy and have perceptual limitations that must be considered while learning a map. This paper considers a mobile robot with sensor perceptual limitations and introduces a new method for exploring and navigating autonomously in indoor environments. To minimize the risk of collisions as well as to not exceed the range of sensors, we introduce the concept of a travel space as a way to ass...

  2. EFFECTS OF MUSIC ON PERCEPTUAL RESPONSES AND PACING STRATEGY

    OpenAIRE

    Flávio de Oliveira Pires; Rômulo Cássio de Moraes Bertuzzi; Adriano Eduardo Lima-Silva; Agedani Pacheco Correia do Rozario; Ana Gabriela de M. Simões; João Paulo Lopes da Silva; Marcos David da Silva-Cavalcante; Thomaz Roberto Carvalho Carnaúba; Fernando Roberto de-Oliveira

    2011-01-01

    CARNAÚBA, T. R. C.; SILVA-CAVALCANTE, M. D.; SILVA, J. P. L.; SIMÕES, A. G. M.; 1, ROZARIO, A. P. C.; BERTUZZI, R. C. M.; PIRES, F. O.; DE-OLIVEIRA, F. R.; LIMA-SILVA, A. E. Effects of music on perceptual responses and pacing strategy. Brazilian Journal of Biomotricity. v. 5, n. 3, p. 210-220, 2011. The purpose of this study was verify the effects of music on perceptual responses and pacing strategy during 5-km running. Fifteen men (22.5 ± 3.5 years; 177.7 ± 6 cm; 76.0 ± 7.0 kg) they accom...

  3. Spatial correlations in attribute communities.

    Directory of Open Access Journals (Sweden)

    Federica Cerina

    Full Text Available Community detection is an important tool for exploring and classifying the properties of large complex networks and should be of great help for spatial networks. Indeed, in addition to their location, nodes in spatial networks can have attributes such as the language for individuals, or any other socio-economical feature that we would like to identify in communities. We discuss in this paper a crucial aspect which was not considered in previous studies which is the possible existence of correlations between space and attributes. Introducing a simple toy model in which both space and node attributes are considered, we discuss the effect of space-attribute correlations on the results of various community detection methods proposed for spatial networks in this paper and in previous studies. When space is irrelevant, our model is equivalent to the stochastic block model which has been shown to display a detectability-non detectability transition. In the regime where space dominates the link formation process, most methods can fail to recover the communities, an effect which is particularly marked when space-attributes correlations are strong. In this latter case, community detection methods which remove the spatial component of the network can miss a large part of the community structure and can lead to incorrect results.

  4. 汉语发展性阅读障碍儿童的视知觉学习*%Visual Perceptual Learning in Chinese Developmental Dyslexia

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    As to the origin and mechanisms of developmental dyslexia, nonlinguistic framework proposes that the phonological and other deficits at the linguistic level may stem from more fundamental deficits in sensory information processing, including acoustic-auditory and auditory temporal processing and visual perceptual processing. Previous studies have shown that visual perceptual deficits of dyslexic children may stem from the deficit in processing more basic visual attributes, as basic visual features are fundamental to higher-level visual processing. Perceptual learning is the improvement of perceptual performance as a function of training (Gibson, 1969), which has been found in various visual tasks involving basic visual features. Here, using visual searching tasks, the main purpose of the present study was to investigate to what extent dyslexic children would show deficits in perceptual processing and learning and whether these deficits are related to their performance in linguistic tasks. Eighteen participants, 9 with dyslexia, 9 chronological age- and nonverbal IQ-matched control children, were screened from a large pool of students in 3, 4, 5 grades with the standardized Chinese written vocabulary test, the reading fluency test and the Raven’s Standard Progressive Matrices test. We tested 9 children in dyslexia group and 9 age-matched children in control group with a parallel search task, a serial search task and a serial search task in restricted time. Study 1 utilized a parallel searching task to examine whether there is a deficit in the basic searching processing and learning in dyslexia group. Study 2 used a serial searching task to explore whether there is a deficit in more complex searching processing and learning. Study 3 adopted a serial searching task with restricted time to investigate whether the ability of serial searching processing will be affected by the restricted time. The results showed that there was no difference between dyslexics and

  5. Geometric Form Drawing: A Perceptual-Motor Approach to Preventive Remediation (The Steiner Approach)

    Science.gov (United States)

    Ogletree, Earl J.

    1975-01-01

    Provided is a rationale for geometric form drawing developed by Rudolf Steiner as a tool to develop motor coordination, perceptual skills, and cognition for mentally retarded and perceptually handicapped children. (Author/CL)

  6. Profit Maximizing Perceptual Positions: An Integrated Theory for the Selection of Product Features and Price

    OpenAIRE

    John R. Hauser; Patricia Simmie

    1981-01-01

    An important component of marketing strategy is to "position" a product in perceptual space. But to realize a perceptual position we must model the link from physical characteristics to perceptual dimensions and we must use this model to maximize profit. This paper integrates psychological theories on how consumers process information with economic models and psychometric measurement, and it develops a theory for selecting physical features and price to achieve a profit maximizing perceptual ...

  7. Brief Periods of Auditory Perceptual Training Can Determine the Sensory Targets of Speech Motor Learning

    OpenAIRE

    Lametti, Daniel R.; Krol, Sonia A.; Shiller, Douglas M.; Ostry, David J.

    2014-01-01

    The perception of speech is notably malleable in adults, yet alterations in perception seem to have little impact on speech production. We hypothesized that speech perceptual training might immediately influence speech motor learning. To test this, we paired a speech perceptual training task with a speech motor learning task. Subjects performed a series of perceptual tests designed to measure and then manipulate the perceptual distinction between the words “head” and “had”. Subjects then prod...

  8. Brain networks of perceptual decision-making: an fMRI ALE meta-analysis

    OpenAIRE

    Max C Keuken; Müller-Axt, Christa; Langner, Robert; Eickhoff, Simon B.; Birte U. Forstmann; Neumann, Jane

    2014-01-01

    In the recent perceptual decision-making literature, a fronto-parietal network is typically reported to primarily represent the neural substrate of human perceptual decision-making. However, the view that only cortical areas are involved in perceptual decision-making has been challenged by several neurocomputational models which all argue that the basal ganglia play an essential role in perceptual decisions. To consolidate these different views, we conducted an Activation Likelihood Estimatio...

  9. A study on the relation of self-esteem,social support and attribution to the subjective well-being of new-age peasant workers%新生代农民工主观幸福感与自尊、社会支持和归因的关系

    Institute of Scientific and Technical Information of China (English)

    李晓东; 汪元宏; 林飞; 刁春元

    2013-01-01

    Objective: To explore the correlation of the self-esteem, social support and attribution with the subjective well-being of new-age peasant workers. Methods; A total of 397 new-age peasant workers were investigated by questionnaires including index of well-being , the feelings of inadequacy scale, social support rating scale and internality, powerful others and chance scale by using stratified cluster sampling. Results:The index of well-being of the new-age peasants was 10. 51 ±1.81, which presents significant age differences ( P 0. 05 ) . The scores of the subjective well-being were positively correlated to the self-esteem( P 0. 05 ). Conclusions: The index of the well-being of the new-age peasants is positively correlated to the scores of self-esteem,social support factors and the total score;the tendencies of different attribution affect their subjective well-being.%目的:探讨新生代农民工主观幸福感与自尊、社会支持和归因的关系.方法:采取分层整群抽样的方法,应用幸福感指数量表、缺陷感量表、社会支持评定量表和内在性、他人及机遇量表,对397名新生代农民工进行问卷调查.结果:新生代农民工幸福感指数为10.51±1.81,幸福感指数年龄差异有统计学意义(P<0.01),性别差异无统计学意义(P>0.05);幸福感指数与自尊总分和社会支持各因子及总分均呈正相关关系(P<0.01);内在性组和有势力的他人组的幸福感指数较机遇组高(P<0.01),内在性组与有势力的他人组的幸福感指数差异无统计学意义(P>0.05).结论:新生代农民工幸福感指数与自尊总分和社会支持各因子及总分均呈正相关关系;不同的归因倾向对其幸福感存在影响.

  10. Adolescents׳ perceptions of peers with depression: An attributional analysis

    OpenAIRE

    Dolphin, Louise; Hennessy, Eilis

    2014-01-01

    Understanding adolescents׳ perceptions of peers with depression is vital in order to tackle peer exclusion and lessen stigmatization. To examine adolescents׳ perceptions of a hypothetical peer with depression, we test an attributional model: that stigma towards persons with mental disorders is influenced by attributions about the causes of their disorders and inferences of personal responsibility. Participants were 401 adolescents from 4th year/10th grade with an age range of 14.75–17.08 year...

  11. Verbal, Numerical and Perceptual Skills Related to Chemistry Achievement.

    Science.gov (United States)

    Bodner, George M.; And Others

    The relationship between students' relative ability in visual-spatial tasks as well as their verbal and numerical skills to their performance in an introductory college chemistry course was investigated. For 700 subjects, verbal and mathematics Scholastic Aptitude Test scores (SAT-V) and (SAT-M) and the following four perceptual tests were…

  12. New Communication Media Technologies: Perceptual, Cognitive, and Aesthetic Effects.

    Science.gov (United States)

    Metallinos, Nikos

    1994-01-01

    Developing visual communication media technologies, such as computerized television, three-dimensional video, digital video interactive (DVI), and high-definition television hinder rather than enhance viewers' perceptual processes, understanding, and aesthetic appreciation of visual messages. Visual communication media researchers should reach out…

  13. Perceptual and Conceptual Distortions of Implicit Hand Maps

    Directory of Open Access Journals (Sweden)

    Matthew R. Longo

    2015-12-01

    Full Text Available Recent studies have revealed that human position sense relies on a massively distorted representation of hand size and shape. By comparing the judged location of landmarks on an occluded hand, Longo and Haggard (2010 constructed implicit perceptual maps of represented hand structure, showing large underestimation of finger length and overestimation of hand width. Here, we investigated the contribution of two potential sources of distortions to such effects: perceptual distortions reflecting spatial warping of the representation of bodily tissue itself, perhaps reflecting distortions of somatotopic cortical maps, and conceptual distortions reflecting mistaken beliefs about the locations of different landmarks within the body. In Experiment 1 we compared distorted hand maps to a task in which participants explicitly judged the location of their knuckles in a hand silhouette. The results revealed the conceptual distortions are responsible for at least part of the underestimation of finger length, but cannot explain overestimation of hand width. Experiment 2 compared distortions of the participant’s own hand based on position sense with a prosthetic hand based on visual memory. Underestimation of finger length was found for both hands, providing further evidence that it reflects a conceptual distortion. In contrast, overestimation of hand width was specific to representation of the participant’s own hand, confirming it reflects a perceptual distortion. Together, these results suggest that distorted body representations do not reflect a single underlying cause. Rather, both perceptual and conceptual distortions contribute to the overall configuration of the hand representation.

  14. Application of Perceptual Filtering Models to Noisy Speech Signals Enhancement

    Directory of Open Access Journals (Sweden)

    Novlene Zoghlami

    2012-01-01

    Full Text Available This paper describes a new speech enhancement approach using perceptually based noise reduction. The proposed approach is based on the application of two perceptual filtering models to noisy speech signals: the gammatone and the gammachirp filter banks with nonlinear resolution according to the equivalent rectangular bandwidth (ERB scale. The perceptual filtering gives a number of subbands that are individually spectral weighted and modified according to two different noise suppression rules. The importance of an accurate noise estimate is related to the reduction of the musical noise artifacts in the processed speech that appears after classic subtractive process. In this context, we use continuous noise estimation algorithms. The performance of the proposed approach is evaluated on speech signals corrupted by real-world noises. Using objective tests based on the perceptual quality PESQ score and the quality rating of signal distortion (SIG, noise distortion (BAK and overall quality (OVRL, and subjective test based on the quality rating of automatic speech recognition (ASR, we demonstrate that our speech enhancement approach using filter banks modeling the human auditory system outperforms the conventional spectral modification algorithms to improve quality and intelligibility of the enhanced speech signal.

  15. Neural mechanisms of perceptual grouping in human visual cortex

    Institute of Scientific and Technical Information of China (English)

    MAO Lihua; HAN Shihui; GUO Chunyan; JIANG Yi

    2004-01-01

    The current work examined neural substrates of perceptual grouping in human visual cortex using event-related potential (ERP) recording. Stimulus arrays consisted of local elements that were either evenly spaced (uniform stimuli) or grouped into columns or rows by proximity or color similarity (grouping stimuli). High-density ERPs were recorded while subjects identified orientations of perceptual groups in stimulus arrays that were presented randomly in one of the four quadrants of the visual field. Both uniform and grouping stimulus arrays elicited an early ERP component (C1), which peaked at about 70 ms after stimulus onset and changed its polarity as a function of stimulated elevations. Dipole modeling based on realistic- head boundary-element models revealed generators of the C1 component in the calcarine cortex. The C1 was modulated by perceptual grouping of local elements based on proximity, and this grouping effect was stronger in the upper than in the lower visual field. The findings provide ERP evidence for the engagement of human primary visual cortex in the early stage of perceptual grouping.

  16. Tongue-Palate Contact of Perceptually Acceptable Alveolar Stops

    Science.gov (United States)

    Lee, Alice; Gibbon, Fiona E.; O'Donovan, Cliona

    2013-01-01

    Increased tongue-palate contact for perceptually acceptable alveolar stops has been observed in children with speech sound disorders (SSD). This is a retrospective study that further investigated this issue by using quantitative measures to compare the target alveolar stops /t/, /d/ and /n/ produced in words by nine children with SSD (20 tokens of…

  17. Perceptual Learning of Acoustic Noise by Individuals with Dyslexia

    Science.gov (United States)

    Agus, Trevor R.; Carrión-Castillo, Amaia; Pressnitzer, Daniel; Ramus, Franck

    2014-01-01

    Purpose: A phonological deficit is thought to affect most individuals with developmental dyslexia. The present study addresses whether the phonological deficit is caused by difficulties with perceptual learning of fine acoustic details. Method: A demanding test of nonverbal auditory memory, "noise learning," was administered to both…

  18. Computer-assisted design in perceptual-motor skills research

    Science.gov (United States)

    Rogers, C. A., Jr.

    1974-01-01

    A categorization was made of independent variables previously found to be potent in simple perceptual-motor tasks. A computer was then used to generate hypothetical factorial designs. These were evaluated in terms of literature trends and pragmatic criteria. Potential side-effects of machine-assisted research strategy were discussed.

  19. Five aspects of maximizing objectivity from perceptual evaluations of loudspeakers

    DEFF Research Database (Denmark)

    Volk, Christer Peter; Bech, Søren; Pedersen, Torben H.; Christensen, Flemming

    2015-01-01

    A literature study was conducted focusing on maximizing objectivity of results from listening evaluations aimed at establishing the relationship between physical and perceptual measurements of loudspeakers. The purpose of the study was to identify and examine factors influencing the objectivity o......, as well as loudspeaker listening in-situ vs. listening to recordings of loudspeakers over headphones....

  20. Political Disenchantment: A Cognitive-Perceptual Theory of Political Alienation.

    Science.gov (United States)

    Long, Samuel

    An investigation of a cognitive-perceptual model to measure adolescents' feelings of political alienation is reported. The model hypothesizes that fundamental to the political alienation process is a feared actual or potential loss of freedom; this process is called psychological reactance. The sample consisted of 460 senior high school students…

  1. Great Expectations: Temporal Expectation Modulates Perceptual Processing Speed

    Science.gov (United States)

    Vangkilde, Signe; Coull, Jennifer T.; Bundesen, Claus

    2012-01-01

    In a crowded dynamic world, temporal expectations guide our attention in time. Prior investigations have consistently demonstrated that temporal expectations speed motor behavior. We explore effects of temporal expectation on "perceptual" speed in three nonspeeded, cued recognition paradigms. Different hazard rate functions for the cue-stimulus…

  2. Perceptual Adaptation of Voice Gender Discrimination with Spectrally Shifted Vowels

    Science.gov (United States)

    Li, Tianhao; Fu, Qian-Jie

    2011-01-01

    Purpose: To determine whether perceptual adaptation improves voice gender discrimination of spectrally shifted vowels and, if so, which acoustic cues contribute to the improvement. Method: Voice gender discrimination was measured for 10 normal-hearing subjects, during 5 days of adaptation to spectrally shifted vowels, produced by processing the…

  3. Teaching perceptual skills in clinical diagnostics using digital media

    NARCIS (Netherlands)

    Scheiter, Katharina; Jarodzka, Halszka

    2011-01-01

    Scheiter, K., & Jarodzka, H. (2011, May). Teaching perceptual skills in clinical diagnostics using digital media. Presentation at the 2nd International Conference “Research in Medical Education”: Shaping diamonds from bench to bedside, Universität Tübingen.

  4. Effects of Zen Meditation on Anxiety Reduction and Perceptual Functioning.

    Science.gov (United States)

    Goldman, Barbara L.; And Others

    1979-01-01

    Subjects were assigned to Zen meditation, antimeditation (control), or no-treatment (control) groups. Measures of anxiety showed a decrease after meditation, but no more than the control groups. State anxiety after stress showed no effect of meditation. Measures of perceptual functioning showed no differential improvement. (Author)

  5. Effect of Listener Training on Perceptual Judgement of Hypernasality

    Science.gov (United States)

    Lee, Alice; Whitehill, Tara L.; Ciocca, Valter

    2009-01-01

    Reliable perceptual judgement is important for documenting the severity of hypernasality, but high reliability can be difficult to obtain. This study investigated the effect of practice and feedback on intra-judge and inter-judge reliability of hypernasality judgements. The judges were 36 speech-language therapy students, who were randomly…

  6. Perceptual Preferences as an Aspect of Adolescent Learning Styles.

    Science.gov (United States)

    Eiszler, Charles F.

    The "Perceptual Preferences" section of the Learning Styles Questionnaire (Dunn and Dunn, 1975) was administered to 170 ninth grade students with self-reported measures of self-esteem, general affect, and achievement (i.e., grade-point average). Data were analyzed to determine if modality preferences are a significant component of student learning…

  7. Symbolic Magnitude Modulates Perceptual Strength in Binocular Rivalry

    Science.gov (United States)

    Paffen, Chris L. E.; Plukaard, Sarah; Kanai, Ryota

    2011-01-01

    Basic aspects of magnitude (such as luminance contrast) are directly represented by sensory representations in early visual areas. However, it is unclear how symbolic magnitudes (such as Arabic numerals) are represented in the brain. Here we show that symbolic magnitude affects binocular rivalry: perceptual dominance of numbers and objects of…

  8. Perceptual Wholes Can Reduce the Conscious Accessibility of Their Parts

    Science.gov (United States)

    Poljac, Ervin; de-Wit, Lee; Wagemans, Johan

    2012-01-01

    Humans can rapidly extract object and category information from an image despite surprising limitations in detecting changes to the individual parts of that image. In this article we provide evidence that the construction of a perceptual whole, or Gestalt, reduces awareness of changes to the parts of this object. This result suggests that the…

  9. Simultaneous Stimulus Preexposure Enhances Human Tactile Perceptual Learning

    Science.gov (United States)

    Rodríguez, Gabriel; Angulo, Rocío

    2014-01-01

    An experiment with human participants established a novel procedure to assess perceptual learning with tactile stimuli. Participants received unsupervised exposure to two sandpaper surfaces differing in roughness (A and B). The ability of the participants to discriminate between the stimuli was subsequently assessed on a same/different test. It…

  10. Listener Agreement for Auditory-Perceptual Ratings of Dysarthria

    Science.gov (United States)

    Bunton, Kate; Kent, Raymond D.; Duffy, Joseph R.; Rosenbek, John C.; Kent, Jane F.

    2007-01-01

    Purpose: Darley, Aronson, and Brown (1969a, 1969b) detailed methods and results of auditory-perceptual assessment for speakers with dysarthrias of varying etiology. They reported adequate listener reliability for use of the rating system as a tool for differential diagnosis, but several more recent studies have raised concerns about listener…

  11. Cognitive-Perceptual Examination of Remediation Approaches to Hypokinetic Dysarthria

    Science.gov (United States)

    McAuliffe, Megan J.; Kerr, Sarah E.; Gibson, Elizabeth M. R.; Anderson, Tim; LaShell, Patrick J.

    2014-01-01

    Purpose: To determine how increased vocal loudness and reduced speech rate affect listeners' cognitive-perceptual processing of hypokinetic dysarthric speech associated with Parkinson's disease. Method: Fifty-one healthy listener participants completed a speech perception experiment. Listeners repeated phrases produced by 5 individuals…

  12. Temporal context for authorship attribution

    DEFF Research Database (Denmark)

    Hansen, Niels Dalum; Lioma, Christina; Larsen, Birger;

    2014-01-01

    A study of temporal aspects of authorship attribution - a task which aims to distinguish automatically between texts written by different authors by measuring textual features. This task is important in a number of areas, including plagiarism detection in secondary education, which we study in this...

  13. k-visit Attribute Grammars

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Skyum, S.

    1981-01-01

    It is shown that any well-defined attribute grammar is k-visit for some k. Furthermore, it is shown that given a well-defined grammar G and an integer k, it is decidable whether G is k-visit. Finally it is shown that the k-visit grammars specify a proper hierarchy with respect to translations...

  14. Perceptual Accent Rating and Attribution in Psychogenic FAS : Some Further Evidence Challenging Whitaker’s Operational Definition.

    NARCIS (Netherlands)

    Keulen, Stefanie; Verhoeven, Jo; Bastiaanse, Yvonne; Marien, P.; Jonkers, Roel; Mavroudakis, Nicolas; Paquier, Philippe

    2016-01-01

    A 40-year-old, non-aphasic, right-handed, and polyglot (L1: French, L2: Dutch, and L3: English) woman with a 12-year history of addiction to opiates and psychoactive substances, and clear psychiatric problems, presented with a foreign accent of sudden onset in L1. Speech evolved toward a mostly flue

  15. The Effect of Kettlebell Swing Load and Cadence on Physiological, Perceptual and Mechanical Variables

    Directory of Open Access Journals (Sweden)

    Michael J. Duncan

    2015-08-01

    Full Text Available This study compared the physiological, perceptual and mechanical responses to kettlebell swings at different loads and swing speeds. Following familiarization 16 strength trained participants (10 males, six females, mean age ± SD = 23 ± 2.9 performed four trials: 2 min kettlebell swings with an 8 kg kettlebell at a fast cadence; 2 min kettlebell swings with an 8 kg kettlebell at a slow cadence; 4 min kettlebell swings with a 4 kg kettlebell at a fast cadence; 4 min kettlebell swings with a 4 kg kettlebell at a slow cadence. Repeated measured analysis of variance indicated no significant differences in peak blood lactate or peak net vertical force across loads and cadences (P > 0.05. Significant main effect for time for heart rate indicated that heart rate was higher at the end of each bout than at mid-point (P = 0.001. A significant Load X cadence interaction for rating of perceived exertion (RPE (P = 0.030 revealed that RPE values were significantly higher in the 8 kg slow cadence condition compared to the 4 kg slow (P = 0.002 and 4 kg fast (P = 0.016 conditions. In summary, this study indicates that the physiological and mechanical responses to kettlebell swings at 4 kg and 8 kg loads and at fast and slow cadence were similar, whereas the perceptual response is greater when swinging an 8 kg kettlebell at slow cadence.

  16. Switching off perceptual learning: Anodal transcranial direct current stimulation (tDCS) at Fp3 eliminates perceptual learning in humans.

    Science.gov (United States)

    Civile, Ciro; Verbruggen, Frederick; McLaren, Rossy; Zhao, Di; Ku, Yixuan; McLaren, I P L

    2016-07-01

    Perceptual learning can be acquired as a result of experience with stimuli that would otherwise be difficult to tell apart, and is often explained in terms of the modulation of feature salience by an error signal based on how well that feature can be predicted by the others that make up the stimulus. In this article we show that anodal transcranial Direct Current Stimulation (tDCS) at Fp3 directly influences this modulation process so as to eliminate and possibly reverse perceptual learning. In 2 experiments, anodal stimulation disrupted perceptual learning (indexed by an inversion effect) compared with sham (Experiment 1) or cathodal (Experiment 2) stimulation. Our findings can be interpreted as showing that anodal tDCS severely reduced or even abolished the modulation of salience based on error, greatly increasing generalization between stimuli. This result supports accounts of perceptual learning based on variations in salience as a consequence of pre-exposure, and opens up the possibility of controlling this phenomenon. (PsycINFO Database Record PMID:27379720

  17. Perceptual Organization Masquerading as Phonological Storage: Further Support for a Perceptual-Gestural View of Short-Term Memory

    Science.gov (United States)

    Jones, Dylan M.; Hughes, Robert W.; Macken, William J.

    2006-01-01

    Three experiments examined whether the survival of the phonological similarity effect (PSE) under articulatory suppression for auditory but not visual to-be-serially recalled lists is a perceptual effect rather than an effect arising from the action of a bespoke phonological store. Using a list of 5 auditory items, a list length at which the…

  18. Cross-Age Tutoring: Effects on Tutors' Attributes.

    Science.gov (United States)

    Yogev, Abraham; Ronen, Rachel

    1982-01-01

    The psychological benefits of a high school tutoring program were investigated. Results gathered from questionnaires answered by high school students tutoring junior high school students, both before and after the tutoring experience, indicated that tutors' empathy, altruism, and self-esteem increased as a result of program participation.…

  19. The Characteristics of Attributes in English

    Institute of Scientific and Technical Information of China (English)

    Deng Hui

    2008-01-01

    This essay focuses on two aspects.One is the characteristic of attribute.The other is concern with some points of using attributes in English.This understanding contributes to using attributes correctly both in written and spoken English.

  20. Is it me or not me? Modulation of perceptual-motor awareness and visuomotor performance by mindfulness meditation

    Directory of Open Access Journals (Sweden)

    Naranjo José

    2012-07-01

    Full Text Available Abstract Background Attribution of agency involves the ability to distinguish our own actions and their sensory consequences which are self-generated from those generated by external agents. There are several pathological cases in which motor awareness is dramatically impaired. On the other hand, awareness-enhancement practices like tai-chi and yoga are shown to improve perceptual-motor awareness. Meditation is known to have positive impacts on perception, attention and consciousness itself, but it is still unclear how meditation changes sensorimotor integration processes and awareness of action. The aim of this study was to investigate how visuomotor performance and self-agency is modulated by mindfulness meditation. This was done by studying meditators’ performance during a conflicting reaching task, where the congruency between actions and their consequences is gradually altered. This task was presented to novices in meditation before and after an intensive 8 weeks mindfulness meditation training (MBSR. The data of this sample was compared to a group of long-term meditators and a group of healthy non-meditators. Results Mindfulness resulted in a significant improvement in motor control during perceptual-motor conflict in both groups. Novices in mindfulness demonstrated a strongly increased sensitivity to detect external perturbation after the MBSR intervention. Both mindfulness groups demonstrated a speed/accuracy trade-off in comparison to their respective controls. This resulted in slower and more accurate movements. Conclusions Our results suggest that mindfulness meditation practice is associated with slower body movements which in turn may lead to an increase in monitoring of body states and optimized re-adjustment of movement trajectory, and consequently to better motor performance. This extended conscious monitoring of perceptual and motor cues may explain how, while dealing with perceptual-motor conflict, improvement in motor

  1. Mathematicians, Attributional Complexity, and Gender

    Science.gov (United States)

    Stalder, Daniel R.

    Given indirect indications in sex role and soda! psychology research that mathematical-deductive reasoning may negatively relate to social acuity, Study 1 investigated whether mathematicians were less attributionally complex than nonmathematicians. Study 1 administered the Attributional Complexity Scale, a measure of social acuity, to female and male faculty members and graduate students in four Midwestern schools. Atlrihutional complexity (AC) is the ability and motivation to give complex explanations for behavior. Study 1 found a significant interaction between field and gender. Only among women did mathematicians score lower on AC. In addition, an established gender difference in AC (that women score higher than men) was present only among nonmathematicians. Studies 2 and 3 offered some preliminary support for the possibility that it is generally female students who score tow on AC who aspire to he mathematicians and for the underlying view that female students' perceived similarity to mathematicians can influence their vocational choices.

  2. Disease proportions attributable to environment

    Directory of Open Access Journals (Sweden)

    Vineis Paolo

    2007-11-01

    Full Text Available Abstract Population disease proportions attributable to various causal agents are popular as they present a simplified view of the contribution of each agent to the disease load. However they are only summary figures that may be easily misinterpreted or over-interpreted even when the causal link between an exposure and an effect is well established. This commentary discusses several issues surrounding the estimation of attributable proportions, particularly with reference to environmental causes of cancers, and critically examines two recently published papers. These issues encompass potential biases as well as the very definition of environment and of environmental agent. The latter aspect is not just a semantic question but carries implications for the focus of preventive actions, whether centred on the material and social environment or on single individuals.

  3. Attribute Search in Online Retailing

    OpenAIRE

    Richards, Timothy J.; Hamilton, Stephen F; Empen, Janine

    2015-01-01

    Online shopping is common in many categories of retail goods. The recent trend towards online retailing has created an unprecedented empirical opportunity to examine consumer search behavior using click stream data. In this paper we examine consumer search intensity across a wide range of grocery products that differ in the depth of product assortment. We develop a model of attribute search in which consumers search within a chosen retailer for products that match their tastes, and that equil...

  4. Narrative attributions of entrepreneurial failure

    OpenAIRE

    Mantere, Saku; Aula, Pekka; Schildt, Henri; Vaara, Eero

    2013-01-01

    We examine how organizational stakeholders use narratives in their psychological processing of venture failure. We identify a range of “narrative attributions”, alternative accounts of failure that actors draw on to process the failure and their role in it. Our analysis provides a view of entrepreneurial failure as a complex social construction, as entrepreneurs, hired executives, employees and the media construct failure in distinctively different ways. Narratives provide means for both ...

  5. Attempting Measurement of Psychological Attributes

    OpenAIRE

    Salzberger, Thomas

    2013-01-01

    Measures of psychological attributes abound in the social sciences as much as measures of physical properties do in the physical sciences. However, there are crucial differences between the scientific underpinning of measurement. While measurement in the physical sciences is supported by empirical evidence that demonstrates the quantitative nature of the property assessed, measurement in the social sciences is, in large part, made possible only by a vague, discretionary definition of measurem...

  6. Attempting measurement of psychological attributes.

    Science.gov (United States)

    Salzberger, Thomas

    2013-01-01

    Measures of psychological attributes abound in the social sciences as much as measures of physical properties do in the physical sciences. However, there are crucial differences between the scientific underpinning of measurement. While measurement in the physical sciences is supported by empirical evidence that demonstrates the quantitative nature of the property assessed, measurement in the social sciences is, in large part, made possible only by a vague, discretionary definition of measurement that places hardly any restrictions on empirical data. Traditional psychometric analyses fail to address the requirements of measurement as defined more rigorously in the physical sciences. The construct definitions do not allow for testable predictions; and content validity becomes a matter of highly subjective judgment. In order to improve measurement of psychological attributes, it is suggested to, first, readopt the definition of measurement in the physical sciences; second, to devise an elaborate theory of the construct to be measured that includes the hypothesis of a quantitative attribute; and third, to test the data for the structure implied by the hypothesis of quantity as well as predictions derived from the theory of the construct. PMID:23550264

  7. Newfound verses attributed to Sanai

    Directory of Open Access Journals (Sweden)

    علی حوری علی حوری

    2011-08-01

    Full Text Available Hakim Sanai is among the few major poets and mystics and is one of the Persian-language primers, whose works created modern developments of the Persian poetry’s content. He was also, in the true sense of the word, “like a thunder that lightened and like a sun that shined,” brightening the road of such poets as Attar and Rumi. The significance of Sanai’s position in literature and mysticism, as well as the position of his poetry has still not been explored as it should be. While examining Sanai’s verses in the prose works, his verses were found in the prose texts of the 6th to 9th century AH/12th to 15th century AD, which do not exist among the popular edited works of this great poet. This article introduces the sources and investigates 43 confirmed verses attributed to Sanai, based on nineteen ancient Persian prose texts, whose authors attribute them to Sanai, or are attributed to him due to coming in the same text with his other verses. This may prove useful for the future edited works of Sanai. Key Words: Sanai, confirmed verses, prose texts, newfound verses.

  8. Client attributions for sexual dysfunction.

    Science.gov (United States)

    Fichten, C S; Spector, I; Libman, E

    1988-01-01

    This investigation examined attributions for sexual dysfunctions made by 63 individuals and 21 of their partners who presented at a sex therapy service for the following problems: erectile dysfunction, premature ejaculation, and female orgasmic dysfunctions. All participants completed measures of marital adjustment, locus of control, depression and a questionnaire which assessed: attributions of responsibility for the sexual problem, perceived control over sexual functioning, distress, effort made to improve the sexual relationship, and expectations about the efficacy of sex therapy for the problem. Results indicate that both identified patients and their partners, regardless of the dysfunction, blamed the sexual problem on the "dysfunctional individual" rather than on the circumstances or the partner. With respect to the partners, husbands of women with orgasmic dysfunction were more likely to blame themselves than the circumstances, while the opposite was true for wives of males with erectile difficulties. Individuals experiencing the dysfunction perceived themselves and their partners as having little, but equal control over the identified patient's sexuality. Correlational analyses indicate that in identified patients, the better the quality of the marital relationship, the greater the self-blame and the lower the partner blame. Those with happy marriages also made greater efforts to improve their sexual relationship and had higher expectations of success with therapy. The implications of the results for research on the role of attributions in sexual dysfunction and for assessment of cognitive factors in sexually dysfunctional individuals and their partners is discussed. PMID:3172253

  9. Electrophysiological correlates associated with contributions of perceptual and conceptual fluency to familiarity

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2015-06-01

    Full Text Available The present research manipulated the fluency of unstudied items using masked repetition priming procedures during an explicit recognition test. Based on fluency-attribution accounts, which posit that familiarity can be driven by multiple forms of fluency, the relationship between masked priming-induced fluency and familiarity was investigated. We classified pictographic characters into High-Meaningfulness (High-M and Low-Meaningfulness (Low-M categories on the basis of subjective meaningfulness ratings and identified the distinct electrophysiological correlates of perceptual and conceptual fluency. The two types of fluency differed in associated ERP effects: 150-250 ms effects for perceptual fluency and FN400 effects for conceptual fluency. The ERPs of Low-M MP-same (items that were preceded by matching masked items false alarms were more positive than correct rejections during 150-250 ms, whereas the ERPs of High-M MP-same false alarms were more positive than correct rejections during 300-500 ms. The topographic patterns of FN400 effects between High-M MP-same false alarms and Low-M MP-same false alarms were not different from those of High-M hits and Low-M hits. These results indicate that both forms of fluency can contribute to familiarity, and the neural correlates of conceptual fluency are not different from those of conceptual priming induced by prior study-phase exposure. We conclude that multiple neural signals potentially contribute to recognition memory, such as numerous forms of fluency differing in terms of their time courses.

  10. The magnetic touch illusion: A perceptual correlate of visuo-tactile integration in peripersonal space.

    Science.gov (United States)

    Guterstam, Arvid; Zeberg, Hugo; Özçiftci, Vedat Menderes; Ehrsson, H Henrik

    2016-10-01

    To accurately localize our limbs and guide movements toward external objects, the brain must represent the body and its surrounding (peripersonal) visual space. Specific multisensory neurons encode peripersonal space in the monkey brain, and neurobehavioral studies have suggested the existence of a similar representation in humans. However, because peripersonal space lacks a distinct perceptual correlate, its involvement in spatial and bodily perception remains unclear. Here, we show that applying brushstrokes in mid-air at some distance above a rubber hand-without touching it-in synchrony with brushstrokes applied to a participant's hidden real hand results in the illusory sensation of a "magnetic force" between the brush and the rubber hand, which strongly correlates with the perception of the rubber hand as one's own. In eight experiments, we characterized this "magnetic touch illusion" by using quantitative subjective reports, motion tracking, and behavioral data consisting of pointing errors toward the rubber hand in an intermanual pointing task. We found that the illusion depends on visuo-tactile synchrony and exhibits similarities with the visuo-tactile receptive field properties of peripersonal space neurons, featuring a non-linear decay at 40cm that is independent of gaze direction and follows changes in the rubber hand position. Moreover, the "magnetic force" does not penetrate physical barriers, thus further linking this phenomenon to body-specific visuo-tactile integration processes. These findings provide strong support for the notion that multisensory integration within peripersonal space underlies bodily self-attribution. Furthermore, we propose that the magnetic touch illusion constitutes a perceptual correlate of visuo-tactile integration in peripersonal space. PMID:27348406

  11. Attributions and Attitudes of Mothers and Fathers in Italy.

    Science.gov (United States)

    Bombi, Anna Silvia; Pastorelli, Concetta; Bacchini, Dario; Di Giunta, Laura; Miranda, Maria C; Zelli, Arnaldo

    2011-07-01

    OBJECTIVE: The present study examined mean level similarities and differences as well as correlations between mothers' and fathers' attributions regarding successes and failures in caregiving situations and progressive versus authoritarian attitudes. DESIGN: Interviews were conducted with both mothers and fathers in 177 Italian families from Rome and Naples. RESULTS: Fathers' attributions reflected higher perceived control over failure than did mothers' attributions, whereas mothers reported attitudes that were more progressive than did fathers. Only the difference in progressive attitudes remained significant after controlling for parents' age, education, and possible social desirability bias. Site differences emerged for four of the seven attributions and attitudes examined; three remained significant after controlling for parents' age, education, and possible social desirability bias. Medium effect sizes were found for concordance between parents in the same family for authoritarian attitudes and modernity of attitudes after controlling for parents' age, education, and possible social desirability bias. CONCLUSIONS: This work elucidates ways that parent gender and cultural context relate to attributions regarding parents' success and failure in caregiving situations and to progressive versus authoritarian parenting attitudes. PMID:21927586

  12. Natural perceptual wayfinding for urban accessibility of the elderly with early-stage AD

    Directory of Open Access Journals (Sweden)

    Giuliana Frau

    2015-04-01

    Full Text Available Population ageing and the increase in neurodegenerative diseases that lead to dementia, together with growing urbanisation, cause us to reflect on an important aspect of life in the city for elderly people: the ability to move around independently without getting lost and to find their way back home. By reviewing the existing literature on the theme of wayfinding and analysing some data on residual capacities in the early stages of Alzheimer’s Disease, the concept of ‘natural perceptual wayfinding’ is introduced, aimed, on the one hand, at improving urban accessibility of people with dementia and, on the other, at reconsidering a topic of vital importance, even if normally neglected in the dwelling design.

  13. PERCEPTUAL RESEMBLANCE OF FACIAL IMAGES: A NEAR SET APPROACH

    Directory of Open Access Journals (Sweden)

    A.MUSTAFI

    Full Text Available In this paper, we introduce a near set approach to image analysis. Near sets result from generalization of rough settheory. One set X is near another set Y to the extent that the description of at least one of the objects in X matches thedescription of at least one of the objects in Y. Near set Evaluation And Recognition (NEAR system is used to measure thedegree of resemblance between facial images. The goal of the NEAR system is to extract perceptual information fromimages using near set theory, which provides a framework for measuring the perceptual nearness of objects. In this work,we have used images from Japanese Female Facial Expression (JAFFE database. The images were first converted intoLocal Binary Patterns (LBP images and then divided into non-overlapping blocks. The degree of nearness of histogramsof all the blocks of one image is measured with the corresponding blocks of another image by using NEAR system

  14. Perceptual-cognitive expertise in elite volleyball players

    Directory of Open Access Journals (Sweden)

    Heloisa eAlves

    2013-03-01

    Full Text Available The goal of the current study was to investigate the relationship between sport expertise and perceptual and cognitive skills, as measured by the component skills approach. We hypothesized that athletes would outperform non-athlete controls in a number of perceptual and cognitive domains and that sport expertise would minimize gender differences. A total of 154 individuals (87 professional volleyball players and 67 non-athlete controls participated in the study. Participants performed a cognitive battery, which included tests of executive control, memory, and visuo-spatial attention. Athletes showed superior performance speed on three tasks (two executive control tasks and one visuo-spatial attentional processing task. In a subset of tasks, gender effects were observed mainly in the control group, supporting the notion that athletic experience can reduce traditional gender effects. The expertise effects obtained substantiate the view that laboratory tests of cognition may indeed enlighten the sport-cognition relationship.

  15. The rapid emergence of stimulus specific perceptual learning

    Directory of Open Access Journals (Sweden)

    Zahra eHussain

    2012-07-01

    Full Text Available Is stimulus specific perceptual learning the result of extended practice or does it emerge early in the time course of learning? We examined this issue by manipulating the amount of practice given on a face identification task on Day 1, and altering the familiarity of stimuli on Day 2. We found that a small number of trials was sufficient to produce stimulus specific perceptual learning of faces: on Day 2, response accuracy decreased by the same amount for novel stimuli regardless of whether observers practiced 105 or 840 trials on Day 1. Current models of learning assume early procedural improvements followed by late stimulus specific gains. Our results show that stimulus specific and procedural improvements are distributed throughout the time course of learning

  16. Postdetonation nuclear debris for attribution

    OpenAIRE

    Fahey, A. J.; Zeissler, C. J.; Newbury, D. E.; Davis, J.; Lindstrom, R.M.

    2010-01-01

    On the morning of July 16, 1945, the first atomic bomb was exploded in New Mexico on the White Sands Proving Ground. The device was a plutonium implosion device similar to the device that destroyed Nagasaki, Japan, on August 9 of that same year. Recently, with the enactment of US public law 111-140, the “Nuclear Forensics and Attribution Act,” scientists in the government and academia have been able, in earnest, to consider what type of forensic-style information may be obtained after a nucle...

  17. Mortality of American alligators attributed to cannibalism

    Science.gov (United States)

    Delany, Michael F.; Woodward, Allan R.; Kiltie, Richard A.; Moore, Clinton T.

    2011-01-01

    Mortality of juvenile (Alligator mississippiensis) attributed to cannibalism on Orange Lake, Florida was examined. Alligator web tags used in mark–recapture studies were found in 12% of 267 stomachs sampled from alligators ≥168 cm TL. Captive alligators retained 76% of force-fed tags during a 588-d tag-retention trial. Models relating the probability of tag recovery to the annual probabilities of juvenile survival, cannibalism, tag retention, adult survival, and adult harvest suggested that cannibalism may on average remove 6–7% of the juvenile alligator population annually. Vulnerability continued to 140 cm TL (age 6–8 yr). Cannibalism of juveniles may serve to regulate the alligator population on Orange Lake. Alligator cannibalism may vary widely among populations, depending on demography and environmental conditions. The role and importance of cannibalism in alligator population dynamics should be more fully assessed and environmental and population factors that influence cannibalism identified to better evaluate management programs.

  18. Perceptual learning of acoustic noise by individuals with dyslexia

    OpenAIRE

    Agus, T.; Carrion Castillo, A.; Pressnitzer, D.; Ramus, F.

    2014-01-01

    Purpose: A phonological deficit is thought to affect most individuals with developmental dyslexia. The present study addresses whether the phonological deficit is caused by difficulties with perceptual learning of fine acoustic details. Method: A demanding test of nonverbal auditory memory, “noise learning,” was administered to both adults with dyslexia and control adult participants. On each trial, listeners had to decide whether a stimulus was a 1-s noise token or 2 abutting presentations o...

  19. The role of culture in perceptual learning styles

    OpenAIRE

    حسینی فاطمی ، پیشقدم حسینی فاطمی ، پیشقدم

    2009-01-01

    The major aim of this article is to determine the role of culture in perceptual learning style (PLS) preferences of Iranian English learners, in order to minimize teacher-student style conflict in the classroom. To do this, 400 university students from different fields of study were selected from Allameh Tabatabaee University in Tehran, Ferdowsi University of Mashhad and Mashhad University of Medical Sciences. The subjects were asked to answer Reid’s questionnaire (1987) which was designed to...

  20. The Accuracy of Saccadic and Perceptual Decisions in Visual Search

    Science.gov (United States)

    Eckstein, Miguel P.; Stone, Leland S.; Beutter, B. B.; Stone, Leland S. (Technical Monitor)

    1997-01-01

    Saccadic eye movements during search for a target embedded in noise are suboptimally guided by information about target location. Our goal is to compare the spatial information used to guide the saccades with that used for the perceptual decision. Three observers were asked to determine the location of a bright disk (diameter = 21 min) in white noise (signal-to-noise ratio = 4.2) from among 10 possible locations evenly spaced at 5.9 deg eccentricity. In the first of four conditions, observers used natural eye movements. In the three remaining conditions, observers fixated a central cross at all times. The fixation conditions consisted of three different presentation times (100, 200, 300 msec), each followed by a mask. Eye-position data were collected, with a resolution of (approximately) 0.2 deg. In the natural viewing condition, we measured. the accuracy with respect to the target and the latency of the first saccade. In the fixation conditions, we discarded trials in which observers broke fixation. Perceptual performance was computed for all conditions. Averaged across observers, the first saccade was correct (closest to the target location) for 56 +/- (SD) % of trials (chance = 10 %) and occurred after a latency of 313 +/- 56 msec. Perceptual performance averaged 53 +/- 4, 63 +/- 4, 65 +/- 2 % correct at 100, 200, and 300 msec, respectively. For the signal-to-noise ratio used, at the time of initiation of the first saccade, there is little difference between the amount of information about target location available to the perceptual and saccadic systems.

  1. The perceptual basis of the feature vowel height

    OpenAIRE

    Chládková, K.; Boersma, P.; Benders, T.

    2015-01-01

    The present study investigated whether listeners perceptually map phonetic information to phonological feature categories or to phonemes. The test case is a phonological feature that occurs in most of the world’s languages, namely vowel height, and its acoustic correlate, the first formant (F1). We first simulated vowel discrimination in virtual listeners who perceive speech sounds through phonological features and virtual listeners who perceive through phonemes. The simulations revealed that...

  2. A Perceptual Image Quality Evaluation based on Local Spatial Information

    OpenAIRE

    Girard, Nathalie; Baudrier, Etienne; Ogier, Jean-Marc

    2009-01-01

    This paper presents a new comparative objective method for image quality evaluation. This method relies on two keys points: a local objective evaluation and a perceptual gathering. The local evaluation concerns the dissimilarities between the degraded image and the reference image ; it is based on a graylevel local Hausdorff distance. This new Hausdorff distance uses a generalized distance transform which is studied here. The evaluation result is a local dissimilarity map (LDMap). In order to...

  3. Spatiotopic perceptual maps in humans: evidence from motion adaptation

    OpenAIRE

    Turi, M.; Burr, D.

    2012-01-01

    How our perceptual experience of the world remains stable and continuous despite the frequent repositioning eye movements remains very much a mystery. One possibility is that our brain actively constructs a spatiotopic representation of the world, which is anchored in external—or at least head-centred—coordinates. In this study, we show that the positional motion aftereffect (the change in apparent position after adaptation to motion) is spatially selective in external rather than retinal coo...

  4. Automatic Perceptual Color Map Generation for Realistic Volume Visualization

    OpenAIRE

    Silverstein, Jonathan C.; Parsad, Nigel M.; Tsirline, Victor

    2008-01-01

    Advances in computed tomography imaging technology and inexpensive high performance computer graphics hardware are making high-resolution, full color (24-bit) volume visualizations commonplace. However, many of the color maps used in volume rendering provide questionable value in knowledge representation and are non-perceptual thus biasing data analysis or even obscuring information. These drawbacks, coupled with our need for realistic anatomical volume rendering for teaching and surgical pla...

  5. Perceptual Adaptation to the Correction of Natural Astigmatism

    OpenAIRE

    Vinas, Maria; Sawides, Lucie; de Gracia, Pablo; Marcos, Susana

    2012-01-01

    Background: The visual system adjusts to changes in the environment, as well as to changes within the observer, adapting continuously to maintain a match between visual coding and visual environment. We evaluated whether the perception of oriented blur is biased by the native astigmatism, and studied the time course of the after-effects following spectacle correction of astigmatism in habitually non-corrected astigmats. Methods and Findings: We tested potential shifts of the perceptual judgme...

  6. Digital visual communications using a Perceptual Components Architecture

    Science.gov (United States)

    Watson, Andrew B.

    1991-01-01

    The next era of space exploration will generate extraordinary volumes of image data, and management of this image data is beyond current technical capabilities. We propose a strategy for coding visual information that exploits the known properties of early human vision. This Perceptual Components Architecture codes images and image sequences in terms of discrete samples from limited bands of color, spatial frequency, orientation, and temporal frequency. This spatiotemporal pyramid offers efficiency (low bit rate), variable resolution, device independence, error-tolerance, and extensibility.

  7. Defining a Link between Perceptual Learning and Attention

    OpenAIRE

    Zhang, Jun-Yun; Kuai, Shu-Guang; Xiao, Lu-Qi; Stanley A Klein; Levi, Dennis M.; Yu, Cong

    2008-01-01

    Perceptual learning of visual features occurs when multiple stimuli are presented in a fixed sequence (temporal patterning), but not when they are presented in random order (roving). This points to the need for proper stimulus coding in order for learning of multiple stimuli to occur. We examined the stimulus coding rules for learning with multiple stimuli. Our results demonstrate that: (1) stimulus rhythm is necessary for temporal patterning to take effect during practice; (2) learning conso...

  8. Perceptual Learning via Modification of Cortical Top-Down Signals

    OpenAIRE

    Schäfer, Roland; Vasilaki, Eleni; Senn, Walter

    2007-01-01

    Author Summary Perceptual learning improves sensory stimulus discrimination by repeated practicing. The improved stimulus discrimination is often thought to arise either from modified stimulus representation in the sensory cortex, or from modified readout from the sensory cortex by higher cortical units. Both explanations, the modified sensory representation and the modified readout, have their advantages and disadvantages. Modifying the stimulus representation within the early sensory cortex...

  9. The non-evidential nature of perceptual experience

    OpenAIRE

    Ghijsen, Harmen

    2014-01-01

    Most internalist views hold that experience provides evidential justification for perceptual belief, although there are different ideas about how experience is able to provide this justification. Evidentialism holds that experiences can act as evidence for belief without having propositional content, while dogmatism holds that only an experience with the content that p can provide prima facie justification for the belief that p. I argue that both views succumb to a version of the well-known S...

  10. Perceptually Valid Facial Expressions for Character-Based Applications

    OpenAIRE

    Ali Arya; Steve DiPaola; Avi Parush

    2009-01-01

    This paper addresses the problem of creating facial expression of mixed emotions in a perceptually valid way. The research has been done in the context of a “game-like” health and education applications aimed at studying social competency and facial expression awareness in autistic children as well as native language learning, but the results can be applied to many other applications such as games with need for dynamic facial expressions or tools for automating the creation of facial animatio...

  11. Fusion of perceptual processes for real-time object tracking

    OpenAIRE

    Jüngling, Kai; Arens, Michael; Hanheide, Marc; Sagerer, Gerhard

    2008-01-01

    This paper introduces a generic architecture for the fusion of perceptual processes and its application in real-time object tracking. In this architecture, the well known anchoring approach is, by integrating techniques from information fusion, extended to multi-modal anchoring so as to be applicable in a multi-process environment. The system architecture is designed to be applicable in a generic way, independent of specific application domains and of the characteristics of the underlying sen...

  12. Interference and feature specificity in visual perceptual learning

    OpenAIRE

    Yotsumoto, Yuko; Chang, Li-Hung; Watanabe, Takeo; Sasaki, Yuka

    2009-01-01

    Perceptual learning (PL) often shows specificity to a trained feature. We investigated whether feature specificity is related to disruption in PL using the texture discrimination task (TDT), which shows learning specificity to background element but not to target element. Learning was disrupted when orientations of background elements were changed in two successive training-sessions (interference) but not in a random order from trial to trial (roving). The presentation of target elements seem...

  13. Perceptual Rivalry: Reflexes Reveal the Gradual Nature of Visual Awareness

    OpenAIRE

    Marnix Naber; Stefan Frässle; Wolfgang Einhäuser

    2011-01-01

    Rivalry is a common tool to probe visual awareness: a constant physical stimulus evokes multiple, distinct perceptual interpretations ("percepts") that alternate over time. Percepts are typically described as mutually exclusive, suggesting that a discrete (all-or-none) process underlies changes in visual awareness. Here we follow two strategies to address whether rivalry is an all-or-none process: first, we introduce two reflexes as objective measures of rivalry, pupil dilation and optokineti...

  14. Predictive context influences perceptual selection during binocular rivalry

    Directory of Open Access Journals (Sweden)

    Rachel N Denison

    2011-12-01

    Full Text Available Prediction may be a fundamental principle of sensory processing: it has been proposed that the brain continuously generates predictions about forthcoming sensory information. However, little is known about how prediction contributes to the selection of a conscious percept from among competing alternatives. Here, we used binocular rivalry to investigate the effects of prediction on perceptual selection. In binocular rivalry, incompatible images presented to the two eyes result in a perceptual alternation between the images, even though the visual stimuli remain constant. If predictive signals influence the competition between neural representations of rivalrous images, this influence should generate a bias in perceptual selection that depends on predictive context. To manipulate predictive context, we developed a novel binocular rivalry paradigm in which rivalrous test images were immediately preceded by a sequence of context images presented identically to the two eyes. One of the test images was consistent with the preceding image sequence (it was the expected next image in the series, and the other was inconsistent (non-predicted. We found that human observers were more likely to perceive the consistent image at the onset of rivalry, suggesting that predictive context biased selection in favor of the predicted percept. This prediction effect was distinct from the effects of adaptation to stimuli presented before the binocular rivalry test. In addition, perceptual reports were speeded for predicted percepts relative to non-predicted percepts. These results suggest that predictive signals related to visual stimulus history exist at neural sites that can bias conscious perception during binocular rivalry. Our paradigm provides a new way to study how prior information and incoming sensory information combine to generate visual percepts.

  15. Perceptual aberrations impair mental own-body transformations

    OpenAIRE

    Mohr, C.; Blanke, O.; Brugger, P

    2006-01-01

    Dysfunctional self and bodily processing have been reported from the schizophrenia spectrum. Here, the authors tested 72 students (40 women) to determine whether performance in a mental own-body transformation task relates to self-rated frequency of spontaneously experienced schizotypal body schema alterations (perceptual aberration). Participants provided speeded left-right decisions concerning the body of a visually depicted human figure (front view vs. back view). For men, reaction times t...

  16. Short term synaptic depression improves information transfer in perceptual multistability

    OpenAIRE

    Zachary P Kilpatrick

    2013-01-01

    Competitive neural networks are often used to model the dynamics of perceptual bistability. Switching between percepts can occur through fluctuations and/or a slow adaptive process. Here, we analyze switching statistics in competitive networks with short term synaptic depression and noise. We start by analyzing a ring model that yields spatially structured solutions and complement this with a study of a space-free network whose populations are coupled with mutual inhibition. Dominance times a...

  17. Factorial Validity of the Mathematics Attribution Scale.

    Science.gov (United States)

    Choroszy, Melisa; And Others

    1984-01-01

    The Mathematics Attribution Scale (MAS) (Algebra) was designed to assess attributions of success and failure in algebra to ability, effort, task, and environment. This study examined the MAS (Algebra) for a separate dimension of attributes for success and a dimension of attributes for failure. The two hypothesized dimensions did not emerge.…

  18. Compreensão de emoções, aceitação social e avaliação de atributos comportamentais em crianças escolares Emotion understanding, social acceptance and evaluation of behavioral attributes in school-age children

    Directory of Open Access Journals (Sweden)

    Gabriela Pavarini

    2011-01-01

    Full Text Available Diversos pesquisadores do campo de estudos sobre teoria da mente têm investigado a relação entre compreensão de emoções e interação social. Seguindo essa linha de investigação, o presente estudo explorou a relação entre compreensão emocional, aceitação social e avaliação de atributos comportamentais pelos pares. Cinquenta e duas crianças escolares responderam a um teste de inteligência emocional e a dois testes de avaliação sociométrica. Não foi encontrada uma correlação entre a compreensão emocional e a aceitação social, porém uma correlação negativa entre a compreensão emocional e a avaliação de atributos ligados à agressividade/disruptividade foi observada. Esses resultados sugerem que o conhecimento de diferentes emoções e de estratégias de regulação emocional podem tornar as crianças menos propensas à agressividade reativa.Several researchers in the theory of mind field have been investigating the relation between emotion understanding and social interaction. Following this line of investigation, the present study explored the relation between emotion understanding, social acceptance and evaluation of behavioral attributes by peers. Fifty-two school-aged children were administered an emotional intelligence test and two instruments of sociometric evaluation. A correlation between emotion understanding and social acceptance was not found, however, a negative correlation between emotion understanding and the evaluation of behavioral attributes related to aggressiveness/disruptivity was observed. The results suggest that the knowledge of different emotions and of emotion regulation strategies may make children less prone to reactive aggressiveness.

  19. Analysis of British Tourists’Hotel Property Perception Based on Perceptual Mapping%基于知觉图的旅华英国游客酒店属性感知分析

    Institute of Scientific and Technical Information of China (English)

    张佑印; 顾静

    2015-01-01

    Based on a survey on six big international tourisms hot spots city,the paper analyzed the behavior of hotel perception of China inbound British visitors by using factor perceptual mapping.From the factor analysis,the hotel’s seven attribute charac-teristic were divided into value dimension and environmental dimension,and then “Perceptual mapping”was used to analyze the different groups tourists’hotel decision behavior.From the results,it could be seen that the British tourists pay close attention to the hotel value when they travel in the natural scenery destination city,while hotel environment were required a high degree of at-tention when they visit cultural tourism city.The female tourists pay more attention both to hotel value and environmental than male tourists.As to different age groups,the hotel decision showed attenuation law to the tourists’age on the hotel value dimen-sion,and showed positive correlation between hotel requirement and tourist age on the hotel environment dimension.As to differ-ent tourists of different states and occupations,the hotel decision showed positive correlation between both hotel value and envi-ronment dimension to tourists’income and motivation.%基于市场调查数据,以旅华英国旅游者为研究对象,运用因子分析与知觉图结合的方法,将酒店7个方面属性因素划分为价值和环境两大维度,并对不同特征游客的感知偏好度进行了对比分析。从结果来看,旅华英国游客对自然风光类目的地城市酒店的价值属性偏好较高,而对文化类旅游城市酒店的环境属性偏好较高;女性对酒店的价值及环境属性的重视程度均高于男性;不同年龄段游客对酒店的价值属性呈现出年龄衰减规律,而对环境属性呈现出年龄递增规律;不同职业游客对酒店属性的感知均与家庭收入和旅游动机有较强关系。

  20. Passive motion reduces vestibular balance and perceptual responses.

    Science.gov (United States)

    Fitzpatrick, Richard C; Watson, Shaun R D

    2015-05-15

    With the hypothesis that vestibular sensitivity is regulated to deal with a range of environmental motion conditions, we explored the effects of passive whole-body motion on vestibular perceptual and balance responses. In 10 subjects, vestibular responses were measured before and after a period of imposed passive motion. Vestibulospinal balance reflexes during standing evoked by galvanic vestibular stimulation (GVS) were measured as shear reaction forces. Perceptual tests measured thresholds for detecting angular motion, perceptions of suprathreshold rotation and perceptions of GVS-evoked illusory rotation. The imposed conditioning motion was 10 min of stochastic yaw rotation (0.5-2.5 Hz ≤ 300 deg s(-2) ) with subjects seated. This conditioning markedly reduced reflexive and perceptual responses. The medium latency galvanic reflex (300-350 ms) was halved in amplitude (48%; P = 0.011) but the short latency response was unaffected. Thresholds for detecting imposed rotation more than doubled (248%; P vestibular sensations of rotation evoked by GVS (mean 113 deg for 10 s at 1 mA) by 44% (P vestibular sensory autoregulation exists and that this probably involves central and peripheral mechanisms, possibly through vestibular efferent regulation. We propose that failure of these regulatory mechanisms at different levels could lead to disorders of movement perception and balance control during standing. PMID:25809702

  1. Enhanced perceptual distance functions and indexing for image replica recognition.

    Science.gov (United States)

    Qamra, Arun; Meng, Yan; Chang, Edward Y

    2005-03-01

    The proliferation of digital images and the widespread distribution of digital data that has been made possible by the Internet has increased problems associated with copyright infringement on digital images. Watermarking schemes have been proposed to safeguard copyrighted images, but watermarks are vulnerable to image processing and geometric distortions and may not be very effective. Thus, the content-based detection of pirated images has become an important application. In this paper, we discuss two important aspects of such a replica detection system: distance functions for similarity measurement and scalability. We extend our previous work on perceptual distance functions, which proposed the Dynamic Partial Function (DPF), and present enhanced techniques that overcome the limitations of DPF. These techniques include the Thresholding, Sampling, and Weighting schemes. Experimental evaluations show superior performance compared to DPF and other distance functions. We then address the issue of using these perceptual distance functions to efficiently detect replicas in large image data sets. The problem of indexing is made challenging by the high-dimensionality and the nonmetric nature of the distance functions. We propose using Locality Sensitive Hashing (LSH) to index images while using the above perceptual distance functions and demonstrate good performance through empirical studies on a very large database of diverse images. PMID:15747793

  2. Perceptual constancy in judgments of egocentric distance: prevailing binocular information

    Directory of Open Access Journals (Sweden)

    Matsushima Elton H.

    2003-01-01

    Full Text Available Binocular cues were considered the prevailing information on specifying depth since the beginning of vision research. In the present study, two perceptual responses, the classical verbal report and a more recent method, open-loop walking, were used to assess the role of binocular information for egocentric distance perception. In two cue conditions environments, full- and reduced-cue, observers judged and walked egocentric distances of stimuli presented at eye-level, under binocular or monocular viewing. Results indicated perceptual constancy for open-loop walking and binocular responses, as well as poor performances under strong degradation on visual information (reduced-cue under monocular viewing, thus presenting evidence to support the fundamental role of binocular information on perception of egocentric distances. Besides that, visually directed actions could be adequate measures of perceived distance, with a better reliability than verbal report, since they were quite free of intrusion of inferential processes and perceptual tendencies. In addition, reduced head movements, side-to-side as well as back and forth deflexion movements, could have contributed to a near perfect coupling between binocular disparity information and open-loop walking responses.

  3. Perceptual enhancement of arteriovenous malformation in MRI angiography displays

    Science.gov (United States)

    Abhari, Kamyar; Baxter, John S. H.; Eagleson, Roy; Peters, Terry; de Ribaupierre, Sandrine

    2012-02-01

    The importance of presenting medical images in an intuitive and usable manner during a procedure is essential. However, most medical visualization interfaces, particularly those designed for minimally-invasive surgery, suffer from a number of issues as a consequence of disregarding the human perceptual, cognitive, and motor system's limitations. This matter is even more prominent when human visual system is overlooked during the design cycle. One example is the visualization of the neuro-vascular structures in MR angiography (MRA) images. This study investigates perceptual performance in the usability of a display to visualize blood vessels in MRA volumes using a contour enhancement technique. Our results show that when contours are enhanced, our participants, in general, can perform faster with higher level of accuracy when judging the connectivity of different vessels. One clinical outcome of such perceptual enhancement is improvement of spatial reasoning needed for planning complex neuro-vascular operations such as treating Arteriovenous Malformations (AVMs). The success of an AVM intervention greatly depends on fully understanding the anatomy of vascular structures. However, poor visualization of pre-operative MRA images makes the planning of such a treatment quite challenging.

  4. NEW VISUAL PERCEPTUAL POOLING STRATEGY FOR IMAGE QUALITY ASSESSMENT

    Institute of Scientific and Technical Information of China (English)

    Zhou Wujie; Jiang Gangyi; Yu Mei

    2012-01-01

    Most of Image Quality Assessment (IQA) metrics consist of two processes.In the first process,quality map of image is measured locally.In the second process,the last quality score is converted from the quality map by using the pooling strategy.The first process had been made effective and significant progresses,while the second process was always done in simple ways.In the second process of the pooling strategy,the optimal perceptual pooling weights should be determined and computed according to Human Visual System (HVS).Thus,a reliable spatial pooling mathematical model based on HVS is an important issue worthy of study.In this paper,a new Visual Perceptual Pooling Strategy (VPPS) for IQA is presented based on contrast sensitivity and luminance sensitivity of HVS.Experimental results with the LIVE database show that the visual perceptual weights,obtained by the proposed pooling strategy,can effectively and significantly improve the performances of the IQA metrics with Mean Structural SIMilarity (MSSIM) or Phase Quantization Code (PQC).It is confirmed that the proposed VPPS demonstrates promising results for improving the performances of existing IQA metrics.

  5. Perceptual learning in the absence of task or stimulus specificity.

    Directory of Open Access Journals (Sweden)

    Ben S Webb

    Full Text Available Performance on most sensory tasks improves with practice. When making particularly challenging sensory judgments, perceptual improvements in performance are tightly coupled to the trained task and stimulus configuration. The form of this specificity is believed to provide a strong indication of which neurons are solving the task or encoding the learned stimulus. Here we systematically decouple task- and stimulus-mediated components of trained improvements in perceptual performance and show that neither provides an adequate description of the learning process. Twenty-four human subjects trained on a unique combination of task (three-element alignment or bisection and stimulus configuration (vertical or horizontal orientation. Before and after training, we measured subjects' performance on all four task-configuration combinations. What we demonstrate for the first time is that learning does actually transfer across both task and configuration provided there is a common spatial axis to the judgment. The critical factor underlying the transfer of learning effects is not the task or stimulus arrangements themselves, but rather the recruitment of commons sets of neurons most informative for making each perceptual judgment.

  6. College Students' Perceived Attributes of Internet Websites and Online Shopping

    Science.gov (United States)

    Seock, Yoo-Kyoung; Norton, Marjorie J. T.

    2008-01-01

    The purpose of this study was to examine perceptions of attributes of clothing retailers' Internet websites in relation to previous and intended future purchase from the websites. Survey data from 414 U.S. college students, non-married and aged 18-22 with online clothing shopping experience and favorite clothing websites were used. Five clothing…

  7. Opposite effects of perceptual and working memory load on perceptual filling-in of an artificial scotoma

    Science.gov (United States)

    Carmel, David; Rees, Geraint

    2016-01-01

    A target presented on a background of dynamic noise disappears from awareness after a few seconds of maintained peripheral viewing. Whereas the effects of bottom-up factors in such filling-in are well documented, the roles of different top-down functions remain relatively unexplored. Here, we investigated the roles of attention and working memory (WM) by manipulating load in concurrent tasks while participants reported filling-in of a peripheral target. In Experiment 1, increasing perceptual load reduced the probability of filling-in and increased the latency of its occurrence. In Experiment 2, increasing WM load shortened the time before filling-in occurred – the opposite effect to increasing perceptual load. These results demonstrate that different top-down functions may have dissociable effects on filling-in. PMID:24168648

  8. Validation of an image-based technique to assess the perceptual quality of clinical chest radiographs with an observer study

    Science.gov (United States)

    Lin, Yuan; Choudhury, Kingshuk R.; McAdams, H. Page; Foos, David H.; Samei, Ehsan

    2014-03-01

    We previously proposed a novel image-based quality assessment technique1 to assess the perceptual quality of clinical chest radiographs. In this paper, an observer study was designed and conducted to systematically validate this technique. Ten metrics were involved in the observer study, i.e., lung grey level, lung detail, lung noise, riblung contrast, rib sharpness, mediastinum detail, mediastinum noise, mediastinum alignment, subdiaphragm-lung contrast, and subdiaphragm area. For each metric, three tasks were successively presented to the observers. In each task, six ROI images were randomly presented in a row and observers were asked to rank the images only based on a designated quality and disregard the other qualities. A range slider on the top of the images was used for observers to indicate the acceptable range based on the corresponding perceptual attribute. Five boardcertificated radiologists from Duke participated in this observer study on a DICOM calibrated diagnostic display workstation and under low ambient lighting conditions. The observer data were analyzed in terms of the correlations between the observer ranking orders and the algorithmic ranking orders. Based on the collected acceptable ranges, quality consistency ranges were statistically derived. The observer study showed that, for each metric, the averaged ranking orders of the participated observers were strongly correlated with the algorithmic orders. For the lung grey level, the observer ranking orders completely accorded with the algorithmic ranking orders. The quality consistency ranges derived from this observer study were close to these derived from our previous study. The observer study indicates that the proposed image-based quality assessment technique provides a robust reflection of the perceptual image quality of the clinical chest radiographs. The derived quality consistency ranges can be used to automatically predict the acceptability of a clinical chest radiograph.

  9. Source attribution of tropospheric ozone

    Science.gov (United States)

    Butler, T. M.

    2015-12-01

    Tropospheric ozone is a harmful pollutant with adverse effects on human health and ecosystems. As well as these effects, tropospheric ozone is also a powerful greenhouse gas, with an anthropogenic radiative forcing one quarter of that of CO2. Along with methane and atmospheric aerosol, tropospheric ozone belongs to the so-called Short Lived Climate forcing Pollutants, or SLCP. Recent work has shown that efforts to reduce concentrations of SLCP in the atmosphere have the potential to slow the rate of near-term climate change, while simultaneously improving public health and reducing crop losses. Unlike many other SLCP, tropospehric ozone is not directly emitted, but is instead influenced by two distinct sources: transport of air from the ozone-rich stratosphere; and photochemical production in the troposphere from the emitted precursors NOx (oxides of nitrogen), CO (Carbon Monoxide), and VOC (volatile organic compounds, including methane). Better understanding of the relationship between ozone production and the emissions of its precursors is essential for the development of targeted emission reduction strategies. Several modeling methods have been employed to relate the production of tropospheric ozone to emissions of its precursors; emissions perturbation, tagging, and adjoint sensitivity methods all deliver complementary information about modelled ozone production. Most studies using tagging methods have focused on attribution of tropospheric ozone production to emissions of NOx, even though perturbation methods have suggested that tropospheric ozone is also sensitive to VOC, particularly methane. In this study we describe the implementation into a global chemistry-climate model of a scheme for tagging emissions of NOx and VOC with an arbitrary number of labels, which are followed through the chemical reactions of tropospheric ozone production in order to perform attribution of tropospehric ozone to its emitted precursors. Attribution is performed to both

  10. Brain networks of perceptual decision-making: an fMRI ALE meta-analysis.

    Directory of Open Access Journals (Sweden)

    Max C Keuken

    2014-06-01

    Full Text Available In the recent perceptual decision-making literature, a fronto-parietal network is typically reported to primarily represent the neural substrate of human perceptual decision-making. However, the view that only cortical areas are involved in perceptual decision-making has been challenged by several neurocomputational models which all argue that the basal ganglia play an essential role in perceptual decisions. To consolidate these different views, we conducted an Activation Likelihood Estimation (ALE meta-analysis on the existing neuroimaging literature. The results argue in favor of the involvement of a frontal-parietal network in general perceptual decision-making that is possibly complemented by the basal ganglia, and modulated in substantial parts by task difficulty. In contrast, expectation of reward, an important aspect of many decision-making processes, shows almost no overlap with the general perceptual decision-making network.

  11. Perceptual organization in computer vision - A review and a proposal for a classificatory structure

    Science.gov (United States)

    Sarkar, Sudeep; Boyer, Kim L.

    1993-01-01

    The evolution of perceptual organization in biological vision, and its necessity in advanced computer vision systems, arises from the characteristic that perception, the extraction of meaning from sensory input, is an intelligent process. This is particularly so for high order organisms and, analogically, for more sophisticated computational models. The role of perceptual organization in computer vision systems is explored. This is done from four vantage points. First, a brief history of perceptual organization research in both humans and computer vision is offered. Next, a classificatory structure in which to cast perceptual organization research to clarify both the nomenclature and the relationships among the many contributions is proposed. Thirdly, the perceptual organization work in computer vision in the context of this classificatory structure is reviewed. Finally, the array of computational techniques applied to perceptual organization problems in computer vision is surveyed.

  12. Distributional Phonetic Learning at 10 Months of Age

    Science.gov (United States)

    Yoshida, Katherine A.; Pons, Ferran; Maye, Jessica; Werker, Janet F.

    2010-01-01

    Infant phonetic perception reorganizes in accordance with the native language by 10 months of age. One mechanism that may underlie this perceptual change is distributional learning, a statistical analysis of the distributional frequency of speech sounds. Previous distributional learning studies have tested infants of 6-8 months, an age at which…

  13. Distinct Mechanisms of Impairment in Cognitive Ageing and Alzheimer's Disease

    Science.gov (United States)

    Mapstone, Mark; Dickerson, Kathryn; Duffy, Charles J.

    2008-01-01

    Similar manifestations of functional decline in ageing and Alzheimer's disease obscure differences in the underlying cognitive mechanisms of impairment. We sought to examine the contributions of top-down attentional and bottom-up perceptual factors to visual self-movement processing in ageing and Alzheimer's disease. We administered a novel…

  14. Research on Radar Emitter Attribute Recognition Method

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In order to solve emitter recognition problems in a practical reconnaissance environment, attribute mathematics is introduced. The basic concepts and theory of attribute set and attribute measure are described in detail. A new attribute recognition method based on attribute measure is presented in this paper. Application example is given, which demonstrates this new method is accurate and effective. Moreover, computer simulation for recognizing the emitter purpose is selected, and compared with classical statistical pattern recognition through simulation. The excellent experimental results demonstrate that this is a brand-new attribute recognition method as compared to existing statistical pattern recognition techniques.

  15. Visual Perception of Procedural Textures: Identifying Perceptual Dimensions and Predicting Generation Models

    OpenAIRE

    LIU Jun; Dong, Junyu; Cai, Xiaoxu; QI, Lin; Chantler, Mike

    2015-01-01

    Procedural models are widely used in computer graphics for generating realistic, natural-looking textures. However, these mathematical models are not perceptually meaningful, whereas the users, such as artists and designers, would prefer to make descriptions using intuitive and perceptual characteristics like "repetitive," "directional," "structured," and so on. To make up for this gap, we investigated the perceptual dimensions of textures generated by a collection of procedural models. Two p...

  16. Perceptual conflict during sensorimotor integration processes - a neurophysiological study in response inhibition

    OpenAIRE

    Chmielewski, Witold X.; Christian Beste

    2016-01-01

    A multitude of sensory inputs needs to be processed during sensorimotor integration. A crucial factor for detecting relevant information is its complexity, since information content can be conflicting at a perceptual level. This may be central to executive control processes, such as response inhibition. This EEG study aims to investigate the system neurophysiological mechanisms behind effects of perceptual conflict on response inhibition. We systematically modulated perceptual conflict by int...

  17. Auditory training during development mitigates a hearing loss-induced perceptual deficit.

    OpenAIRE

    Emma Sarro; Dan Sanes

    2014-01-01

    Sensory experience during early development can shape the central nervous system and this is thought to influence adult perceptual skills. In the auditory system, early induction of conductive hearing loss (CHL) leads to deficits in central auditory coding properties in adult animals, and this is accompanied by diminished perceptual thresholds. In contrast, a brief regimen of auditory training during development can enhance the perceptual skills of animals when tested in adulthood. Here, we a...

  18. Perceptually Optimised Loudspeaker Selection For the Creation Of Personal Sound Zones

    DEFF Research Database (Denmark)

    Francombe, J.; Coleman, P.; Olik, M.;

    2013-01-01

    it is desirable to consider perceptual factors. A search procedure was used to select 5 loudspeakers for production of 2 sound zones using acoustic contrast control. Comparisons were made between searches driven by physical (programme-independent TIR) and perceptual (distraction predictions from a...... statistical model) cost func- tions. Performance was evaluated on TIR and predicted distraction in addition to subjective ratings. The perceptual cost function showed some bene ts over physical optimisation, although the model used needs further work....

  19. Anxiety and perceptual-motor performance: toward an integrated model of concepts, mechanisms, and processes

    OpenAIRE

    Nieuwenhuys, Arne; Oudejans, Raôul R. D.

    2011-01-01

    Under anxiety, people sometimes perform poorly. This concerns cognitive performance (e.g., taking an important exam) as well as perceptual-motor performance (e.g., picking up a cup from a table). There is still much debate about how anxiety affects perceptual-motor performance. In the current paper we review the experimental literature on anxiety and perceptual-motor performance, thereby focusing on how anxiety affects the perception, selection, and realization of action possibilities. Based ...

  20. Perceptual Learning and Abstraction in Machine Learning : an application to autonomous robotics

    OpenAIRE

    Bredeche, Nicolas; Shi, Zhongzhi; Zucker, Jean-Daniel

    2006-01-01

    This paper deals with the possible benefits of Perceptual Learning in Artificial Intelligence. On the one hand, Perceptual Learning is more and more studied in neurobiology and is now considered as an essential part of any living system. In fact, Perceptual Learning and Cognitive Learning are both necessary for learning and often depends on each other. On the other hand, many works in Machine Learning are concerned with "Abstraction" in order to reduce the amount of complexity related to some...

  1. Relationship between perceptual learning in speech and statistical learning in younger and older adults

    OpenAIRE

    Thordis Marisa Neger; Esther Janse

    2014-01-01

    Within a few sentences, listeners learn to understand severely degraded speech such as noise-vocoded speech. However, individuals vary in the amount of such perceptual learning and it is unclear what underlies these differences. The present study investigates whether perceptual learning in speech relates to statistical learning, as sensitivity to probabilistic information may aid identification of relevant cues in novel speech input. If statistical learning and perceptual learning (partly) dr...

  2. Perceptual Learning in Children With Visual Impairment Improves Near Visual Acuity

    OpenAIRE

    Huurneman, B.; Boonstra, F.N.; Cox, R.F.A.; van Rens, G. H M B; Cillessen, A.H.N.

    2013-01-01

    PURPOSE. This study investigated whether visual perceptual learning can improve near visual acuity and reduce foveal crowding effects in four-to nine-year-old children with visual impairment. METHODS. Participants were 45 children with visual impairment and 29 children with normal vision. Children with visual impairment were divided into three groups: a magnifier group (n = 12), a crowded perceptual learning group (n = 18), and an uncrowded perceptual learning group (n = 15). Children with no...

  3. A cross-cultural listener-based study on perceptual features in K-pop

    OpenAIRE

    SCHÖN, RAGNAR

    2015-01-01

    Recent research within the Music Information Retrieval (MIR) field has shown the relevance of perceptual features for musical signals. The idea is to identify a small set of features that are natural descriptions from a perceptual perspective. The notion of perceptual features is based on the ecological approach to music, that is, focussing on sound events rather than spectral information. Furthermore, MIR research has had an overemphasis on Western music and listeners. This leads to the ques...

  4. Top-down (Prior Knowledge) and Bottom-up (Perceptual Modality) Influences on Spontaneous Interpersonal Synchronization.

    Science.gov (United States)

    Gipson, Christina L; Gorman, Jamie C; Hessler, Eric E

    2016-04-01

    Coordination with others is such a fundamental part of human activity that it can happen unintentionally. This unintentional coordination can manifest as synchronization and is observed in physical and human systems alike. We investigated the role of top-down influences (prior knowledge of the perceptual modality their partner is using) and bottom-up factors (perceptual modality combination) on spontaneous interpersonal synchronization. We examine this phenomena with respect to two different theoretical perspectives that differently emphasize top-down and bottom-up factors in interpersonal synchronization: joint-action/shared cognition theories and ecological-interactive theories. In an empirical study twelve dyads performed a finger oscillation task while attending to each other's movements through either visual, auditory, or visual and auditory perceptual modalities. Half of the participants were given prior knowledge of their partner's perceptual capabilities for coordinating across these different perceptual modality combinations. We found that the effect of top-down influence depends on the perceptual modality combination between two individuals. When people used the same perceptual modalities, top-down influence resulted in less synchronization and when people used different perceptual modalities, top-down influence resulted in more synchronization. Furthermore, persistence in the change in behavior as a result of having perceptual information about each other ('social memory') was stronger when this top-down influence was present. PMID:27033133

  5. Perceptual Changes in Response to Two Regimens of Interval Training in Sedentary Women.

    Science.gov (United States)

    Astorino, Todd A; Schubert, Matthew M; Palumbo, Elyse; Stirling, Douglas; McMillan, David W; Gallant, Rachael; Dewoskin, Ruthie

    2016-04-01

    Astorino, TA, Schubert, MM, Palumbo, E, Stirling, D, McMillan, DW, Gallant, R, and Dewoskin, R. Perceptual changes in response to two regimens of interval training in sedentary women. J Strength Cond Res 30(4): 1067-1076, 2016-This study examined acute and chronic changes in perceptual measures (rating of perceived exertion [RPE], affect, and arousal) in response to 2 regimens of high-intensity interval training (HIIT). Twenty-three healthy sedentary women (mean ± SD age and V[Combining Dot Above]O2max = 23.0 ± 5.7 years and 30.1 ± 4.4 ml·kg·min, respectively) were randomized to complete 12 weeks of one of 2 HIIT regimes, whereas an additional 7 women served as sedentary controls. Training was performed 3 days per week on a cycle ergometer and consisted of up to ten 1-minute bouts at moderate (60-80%Wmax = moderate intensity [MOD]) or more intense (80-90%Wmax = HI) workloads separated by active recovery. At baseline and every 3 weeks, RPE, affect, and arousal were measured during training using validated scales. Repeated measures analysis of variance was used to examine acute and chronic changes in these variables to HIIT. Data revealed significant (p HIIT, with RPE responses differing (p ≤ 0.05) between HI and MOD. However, acute changes in affect and arousal were similar in HI and MOD. Training led to a significant reduction in RPE, whereas both affect and arousal were unchanged (p > 0.05) after HIIT. Completion of moderate or more intense interval training reduces perceptions of RPE during training yet does not alter arousal or affect. RPE was reduced via training, yet large dependence on anaerobic metabolism during HIIT may minimize training-induced changes in affect. PMID:26340468

  6. Attribution theory in science achievement

    Science.gov (United States)

    Craig, Martin

    Recent research reveals consistent lags in American students' science achievement scores. Not only are the scores lower in the United States compared to other developed nations, but even within the United States, too many students are well below science proficiency scores for their grade levels. The current research addresses this problem by examining potential malleable factors that may predict science achievement in twelfth graders using 2009 data from the National Assessment of Educational Progress (NAEP). Principle component factor analysis was conducted to determine the specific items that contribute to each overall factor. A series of multiple regressions were then analyzed and formed the predictive value of each of these factors for science achievement. All significant factors were ultimately examined together (also using multiple regression) to determine the most powerful predictors of science achievement, identifying factors that predict science achievement, the results of which suggested interventions to strengthen students' science achievement scores and encourage persistence in the sciences at the college level and beyond. Although there is a variety of research highlighting how students in the US are falling behind other developing nations in science and math achievement, as yet, little research has addressed ways of intervening to address this gap. The current research is a starting point, seeking to identify malleable factors that contribute to science achievement. More specifically, this research examined the types of attributions that predict science achievement in twelfth grade students.

  7. Perceptual advertisement by the prey of stalking or ambushing predators.

    Science.gov (United States)

    Broom, Mark; Ruxton, Graeme D

    2012-12-21

    There has been previous theoretical explorations of the stability of signals by prey that they have detected a stalking or ambush predator, where such perceptual advertisement dissuades the predator from attacking. Here we use a game theoretical model to extend the theory to consider some empirically-motivated complexities: (i) many perceptual advertisement signals appear to have the potential to vary in intensity, (ii) higher intensity signals are likely to be most costly to produce, and (iii) some high-cost signals (such as staring directly at the predator) can only be utilised if the prey is very confident of the existence of a nearby predator (that is, there are reserved or unfakable signals). We demonstrate that these complexities still allow for stable signalling. However, we do not find solutions where prey use a range of signal intensities to signal different degrees of confidence in the proximity of a predator; with prey simply adopting a binary response of not signalling or always signalling at the same fixed level. However this fixed level will not always be the cheapest possible signal, and we predict that prey that require more certainty about proximity of a predator will use higher-cost signals. The availability of reserved signals does not prohibit the stability of signalling based on lower-cost signals, but we also find circumstances where only the reserved signal is used. We discuss the potential to empirically test our model predictions, and to develop theory further to allow perceptual advertisement to be combined with other signalling functions. PMID:22960570

  8. Perceptual anchoring in preschool children: not adultlike, but there.

    Directory of Open Access Journals (Sweden)

    Karen Banai

    Full Text Available BACKGROUND: Recent studies suggest that human auditory perception follows a prolonged developmental trajectory, sometimes continuing well into adolescence. Whereas both sensory and cognitive accounts have been proposed, the development of the ability to base current perceptual decisions on prior information, an ability that strongly benefits adult perception, has not been directly explored. Here we ask whether the auditory frequency discrimination of preschool children also improves when given the opportunity to use previously presented standard stimuli as perceptual anchors, and whether the magnitude of this anchoring effect undergoes developmental changes. METHODOLOGY/PRINCIPAL FINDINGS: Frequency discrimination was tested using two adaptive same/different protocols. In one protocol (with-reference, a repeated 1-kHz standard tone was presented repeatedly across trials. In the other (no-reference, no such repetitions occurred. Verbal memory and early reading skills were also evaluated to determine if the pattern of correlations between frequency discrimination, memory and literacy is similar to that previously reported in older children and adults. Preschool children were significantly more sensitive in the with-reference than in the no-reference condition, but the magnitude of this anchoring effect was smaller than that observed in adults. The pattern of correlations among discrimination thresholds, memory and literacy replicated previous reports in older children. CONCLUSIONS/SIGNIFICANCE: The processes allowing the use of context to form perceptual anchors are already functional among preschool children, albeit to a lesser extent than in adults. Nevertheless, immature anchoring cannot fully account for the poorer frequency discrimination abilities of young children. That anchoring is present among the majority of typically developing preschool children suggests that the anchoring deficits observed among individuals with dyslexia represent a

  9. Attributional theory, organisational culture and motivation

    OpenAIRE

    Xenikou, A.

    1995-01-01

    This thesis concerns the effect of attributions for failing in a creativity task and organisational culture (OC) on motivation to engage in similar tasks. In chapter one the relationship between situational attributions, attributional style (AS), and motivation is reviewed. A reformulation of Amabile's model of the social psychology of creativity is suggested on the grounds of recent developments in attributional theory. An extension of Amabile's theory is also proposed by inve...

  10. Detecting Structure-correlated Attributes on Graphs

    OpenAIRE

    Chen, Siheng; Yang, Yaoqing; Zong, Shi; Singh, Aarti; Kovačević, Jelena

    2016-01-01

    Do users from Carnegie Mellon University form social communities on Facebook? In this paper, we focus on a task of detecting structure-correlated attributes on a graph. A structure-correlated attribute means that the node set activated by the attribute form a community in the graph. This task is relevant to many applications including identifying structure-correlated attributes in social networks, special events in the urban traffic networks, unusual brain activity in the brain connectivity n...

  11. Attributions and requirements of Islamic leadership

    OpenAIRE

    Dahlena Sari Marbun

    2013-01-01

    Purpose – The purpose of this paper is to look into the relationship between attribution and requirements of Islamic leadership. Design/methodology/approach – This paper describes concepts of attribution and requirements of leadership and links them to related Islamic concepts. Findings - A correlation is found to exist between attribution and requirements of “conventional” and Islamic leadership. Research limitations/implications - Being a practical endeavor, attribution and requirements of ...

  12. The eyes in imagery and perceptual processes: first remarks.

    Science.gov (United States)

    Ruggieri, V; Alfieri, G

    1992-08-01

    Through an echographic system we examined the activity of the crystalline lens of 10 men and women during real perceptual activity and during imagery. Subjects had to perceive near and far stimuli and to imagine reading a word on a page of a book (near imagined stimulus) or seeing a ship on the horizon (far imagined stimulus). Results showed that processes of accommodation (linked to the variations of the optical axis of the crystalline lens) occur in both real and imaginative conditions. The first results suggest an active role of the eye during imagery. PMID:1528683

  13. Perceptual Effects of Dynamic Range Compression in Popular Music Recordings

    DEFF Research Database (Denmark)

    Hjortkjær, Jens; Walther-Hansen, Mads

    There is a widespread belief that the increasing use of dynamic range compression in music mastering (the loudnesswar) deteriorates sound quality but experimental evidence of perceptual effects is lacking. In this study, normal hearing listeners were asked to evaluate popular music recordings in...... original versions and in remastered versions with higher levels of dynamic range compression. Surprisingly, we found no evidence of preference for the less compressed music. We also failed to find differences in ratings of perceived "depth" between the original and more compressed audio. A low degree of...

  14. Objectively measured descriptors for perceptual characterization of speakers

    Science.gov (United States)

    Necioglu, Burhan Fazil

    Speaker recognizability has long been identified as one component in the evaluation process of communications systems. Although the intelligibility and voice quality aspects of evaluation have taken relative precedence, with more widespread use of lower bit rate speech coders, speaker recognizability emerges as an additional major issue. Still, subjective testing of speaker recognizability is intricate, time consuming and very expensive; so potentially, using objectively measurable descriptors to augment the subjective speaker recognizability tests could result in increased efficiency and reliability. This thesis presents a variety of descriptors objectively extracted from the speech waveform that might be useful in characterizing and interpreting perceptual speaker differences. These descriptors belong to the three broad classes of prosodic, vocal tract and glottal properties of speech production, and include various measurements on pitch and energy contours, formant related statistics, average vocal tract length estimates, and glottal pulse parameters. To assess the potential for this large set of speech waveform descriptors, reliability, RMS measurement noise and strength of speaker clustering were estimated using sets of 86 male and 78 female TIMIT speakers. The actual speaker discrimination abilities of the descriptors were determined by maximum-likelihood same/different classification of speaker pairs using their utterance pair measurement distances, without the need to model individual speakers. Using pairs of utterances approximately 12 seconds in length, and combining the likelihood scores of ten descriptors from all three broad classes, it was possible to make zero same-speaker classification errors, while achieving a different-speaker classification error rate of less than 1%, on separate testing/training speaker sets. When utterance lengths were reduced by half, the average error rate stayed below 4%. The perceptual relevance of this set of descriptors

  15. Perceptual differentiation and category effects in normal object recognition

    DEFF Research Database (Denmark)

    Gerlach, Christian; Law, I; Gade, A;

    1999-01-01

    The purpose of the present PET study was (i) to investigate the neural correlates of object recognition, i.e. the matching of visual forms to memory, and (ii) to test the hypothesis that this process is more difficult for natural objects than for artefacts. This was done by using object decision...... may be the neural correlate of matching visual forms to memory, and the amount of activation in these regions may correspond to the degree of perceptual differentiation required for recognition to occur. With respect to behaviour, it took significantly longer to make object decisions on natural...

  16. More Than Meets the Eye: The Merging of Perceptual and Conceptual Knowledge in the Anterior Temporal Face Area

    Science.gov (United States)

    Collins, Jessica A.; Koski, Jessica E.; Olson, Ingrid R.

    2016-01-01

    An emerging body of research has supported the existence of a small face sensitive region in the ventral anterior temporal lobe (ATL), referred to here as the “anterior temporal face area”. The contribution of this region in the greater face-processing network remains poorly understood. The goal of the present study was to test the relative sensitivity of this region to perceptual as well as conceptual information about people and objects. We contrasted the sensitivity of this region to that of two highly-studied face-sensitive regions, the fusiform face area (FFA) and the occipital face area (OFA), as well as a control region in early visual cortex (EVC). Our findings revealed that multivoxel activity patterns in the anterior temporal face area contain information about facial identity, as well as conceptual attributes such as one’s occupation. The sensitivity of this region to the conceptual attributes of people was greater than that of posterior face processing regions. In addition, the anterior temporal face area overlaps with voxels that contain information about the conceptual attributes of concrete objects, supporting a generalized role of the ventral ATLs in the identification and conceptual processing of multiple stimulus classes. PMID:27199711

  17. New conditions on the role of color in perceptual organization and an extension to how color influences reading

    Directory of Open Access Journals (Sweden)

    Pinna Baingio

    2014-01-01

    Full Text Available Color is one among many attributes that are involved in the similarity principle. Grouping by color is believed to be less effective when compared with other attributes such as shape and luminance. The main purpose of this work is to explore the role played by color in determining visual grouping and wholeness, not only in relation to further similarity attributes but also to other principles such as proximity, good continuation and past experience. Conditions, different from those used by Gestalt psychologists, were chosen, and aimed to understand how color can influence visual organization and through it, other perceptual and complex processes such as reading and visual word recognition. In fact, involving cognitive and metacognitive domains, permits exploration of broader issues concerning perception, memory, knowledge, representation and learning, where color can express its biological advantages for humans more clearly. These processes can be assimilated to the Gestalt past experience considered as a principle of its own kind not fully explored in relation to the other principles. As a consequence, these conditions allow color to be pitted against past experience and against a number of principles at the same time. The results demonstrated that color can strongly influence grouping, shape and the process of segmentation of words involved in the reading task. Therefore, color not only is one among the many principles of grouping but an essential component for the foundation of the more complex organization aimed at creating wholeness, part-whole formation and fragmentation.

  18. 1997 & 1998 Smoking-Attributable Mortality Report

    OpenAIRE

    Bryant, Jennifer B.S.; Thompson, Dan M.P.H.; Hopkins, Richard M.D., M.S.P.H.; Florida Department of Health, Brueau of Epidemiology

    1999-01-01

    Between 1997 and 1998, the percentage of smoking-attributable deaths compared with all deaths by all causes in Florida remained steady. During 1997 an estimated 18.90% of all deaths in Florida were attributable to cigarette smoking, and 18.74% were smoking-attributable in 1998. Using the Smoking-Attributable Mortality, Morbidity and Economic Costs (SAMMEC 3.0) software program, developed by the Centers for Disease Control and Prevention, as a model, Florida’s smoking-attributable deaths were ...

  19. Perpetrator characteristics and blame attributions in a stranger rape situation

    Directory of Open Access Journals (Sweden)

    Leif A. Strömwall

    2014-07-01

    Full Text Available Both real-life events and research show that rape victims are sometimes blamed for their victimization. The effect of perpetrator characteristics on victim blaming has rarely been studied. In an experiment using a community sample (N = 161, we investigated the effect of the perpetrator's previous conviction and age, as well as participants' gender and belief in a just world (BJW on blame attributions using a vignette methodology. It was predicted that less victim blame and more perpetrator blame would be attributed when the perpetrator had a previous conviction. Results showed that level of BJW was associated with victim blame (positively and perpetrator blame (negatively. Men blamed the victim more and women blamed the victim less when the perpetrator had a previous conviction. Women blamed the perpetrator more and men less when the perpetrator had a previous conviction. Hence, gender is an important factor in explaining variation in blame attributions.

  20. Attribute oriented induction with star schema

    Directory of Open Access Journals (Sweden)

    Spits Warnars H.L.H

    2010-05-01

    Full Text Available This paper will propose a novel star schema attribute induction as a new attributeinduction paradigm and as improving from current attribute oriented induction. A novelstar schema attribute induction will be examined with current attribute oriented inductionbased on characteristic rule and using non rule based concept hierarchy by implementingboth of approaches. In novel star schema attribute induction some improvements havebeen implemented like elimination threshold number as maximum tuples control forgeneralization result, there is no ANY as the most general concept, replacement the roleconcept hierarchy with concept tree, simplification for the generalization strategy stepsand elimination attribute oriented induction algorithm. Novel star schema attributeinduction is more powerful than the current attribute oriented induction since can producesmall number final generalization tuples and there is no ANY in the results.

  1. Perceptual security of encrypted images based on wavelet scaling analysis

    Science.gov (United States)

    Vargas-Olmos, C.; Murguía, J. S.; Ramírez-Torres, M. T.; Mejía Carlos, M.; Rosu, H. C.; González-Aguilar, H.

    2016-08-01

    The scaling behavior of the pixel fluctuations of encrypted images is evaluated by using the detrended fluctuation analysis based on wavelets, a modern technique that has been successfully used recently for a wide range of natural phenomena and technological processes. As encryption algorithms, we use the Advanced Encryption System (AES) in RBT mode and two versions of a cryptosystem based on cellular automata, with the encryption process applied both fully and partially by selecting different bitplanes. In all cases, the results show that the encrypted images in which no understandable information can be visually appreciated and whose pixels look totally random present a persistent scaling behavior with the scaling exponent α close to 0.5, implying no correlation between pixels when the DFA with wavelets is applied. This suggests that the scaling exponents of the encrypted images can be used as a perceptual security criterion in the sense that when their values are close to 0.5 (the white noise value) the encrypted images are more secure also from the perceptual point of view.

  2. Lexical-perceptual integration influences sensorimotor adaptation in speech

    Directory of Open Access Journals (Sweden)

    Nicolas Jean Bourguignon

    2014-04-01

    Full Text Available A combination of lexical bias and altered auditory feedback was used to investigate the influence of higher-order linguistic knowledge on the perceptual aspects of speech motor control. Subjects produced monosyllabic real words or pseudo-words containing the vowel [ε] (as in "head" under conditions of altered auditory feedback involving a decrease in vowel first formant (F1 frequency. This manipulation had the effect of making the vowel sound more similar to [I] (as in "hid", affecting the lexical status of produced words in two Lexical-Change (LC groups (either changing them from real words to pseudo-words: e.g., less – liss, or pseudo-words to real words: e.g., kess – kiss. Two No-Lexical-Change (NLC control groups underwent the same auditory feedback manipulation during the production of [ε] real- or pseudo-words, only without any resulting change in lexical status (real words to real words: e.g., mess – miss, or pseudo-words to pseudo-words: e.g., ness – niss. The results from the LC groups indicate that auditory-feedback-based speech motor learning is sensitive to the lexical status of the stimuli being produced, in that speakers tend to keep their acoustic speech outcomes within the auditory-perceptual space corresponding to the task-related side of the word/non-word boundary (real words or pseudo-words. For the NLC groups, however, no such effect of lexical status is observed.

  3. Shared Neural Substrates of Emotionally Enhanced Perceptual and Mnemonic Vividness

    Directory of Open Access Journals (Sweden)

    Rebecca M. Todd

    2013-05-01

    Full Text Available It is well known that emotionally salient events are remembered more vividly than mundane ones. Our recent research has demonstrated that such memory vividness is due in part to the subjective experience of emotional events as more perceptually vivid, an effect we call emotion-enhanced vividness, or EEV. The present study built on previously reported research in which fMRI data were collected while participants rated relative levels of visual noise overlaid on emotionally salient and neutral images. Ratings of greater EEV were associated with greater activation in the amygdala, visual cortex, and posterior insula. In the present study, we measured BOLD activation that predicted recognition memory vividness for these same images one week later. Results showed that, after controlling for differences between scenes in low-level objective features, hippocampus activation uniquely predicted subsequent memory vividness. In contrast, amygdala and visual cortex regions that were sensitive to EEV were also modulated by subsequent ratings of memory vividness. These findings suggest shared neural substrates for the influence of emotional salience on perceptual and mnemonic vividness, with amygdala and visual cortex activation at encoding contributing to the experience of both perception and subsequent memory.

  4. Compressed image quality metric based on perceptually weighted distortion.

    Science.gov (United States)

    Hu, Sudeng; Jin, Lina; Wang, Hanli; Zhang, Yun; Kwong, Sam; Kuo, C-C Jay

    2015-12-01

    Objective quality assessment for compressed images is critical to various image compression systems that are essential in image delivery and storage. Although the mean squared error (MSE) is computationally simple, it may not be accurate to reflect the perceptual quality of compressed images, which is also affected dramatically by the characteristics of human visual system (HVS), such as masking effect. In this paper, an image quality metric (IQM) is proposed based on perceptually weighted distortion in terms of the MSE. To capture the characteristics of HVS, a randomness map is proposed to measure the masking effect and a preprocessing scheme is proposed to simulate the processing that occurs in the initial part of HVS. Since the masking effect highly depends on the structural randomness, the prediction error from neighborhood with a statistical model is used to measure the significance of masking. Meanwhile, the imperceptible signal with high frequency could be removed by preprocessing with low-pass filters. The relation is investigated between the distortions before and after masking effect, and a masking modulation model is proposed to simulate the masking effect after preprocessing. The performance of the proposed IQM is validated on six image databases with various compression distortions. The experimental results show that the proposed algorithm outperforms other benchmark IQMs. PMID:26415170

  5. Exploration and Navigation for Mobile Robots With Perceptual Limitations

    Directory of Open Access Journals (Sweden)

    Eduardo F. Morales

    2008-11-01

    Full Text Available To learn a map of an environment a mobile robot has to explore its workspace using its sensors. Sensors are noisy and have perceptual limitations that must be considered while learning a map. This paper considers a mobile robot with sensor perceptual limitations and introduces a new method for exploring and navigating autonomously in indoor environments. To minimize the risk of collisions as well as to not exceed the range of sensors, we introduce the concept of a travel space as a way to associate costs to grid cells of the map, based on distances to obstacles. During exploration the mobile robot minimizes its movements, including rotations, to reach the nearest unexplored region of the environment, using a dynamic programming algorithm. Once the exploration ends, the travel space is used to form a roadmap, a net of safe roads that the mobile robot can use for navigation. These exploration and navigation method are tested using a simulated and a real mobile robot with promising results.

  6. Beauty in abstract paintings: perceptual contrast and statistical properties

    Science.gov (United States)

    Mallon, Birgit; Redies, Christoph; Hayn-Leichsenring, Gregor U.

    2014-01-01

    In this study, we combined the behavioral and objective approach in the field of empirical aesthetics. First, we studied the perception of beauty by investigating shifts in evaluation on perceived beauty of abstract artworks (Experiment 1). Because the participants showed heterogeneous individual preferences for the paintings, we divided them into seven clusters for the test. The experiment revealed a clear pattern of perceptual contrast. The perceived beauty of abstract paintings increased after exposure to paintings that were rated as less beautiful, and it decreased after exposure to paintings that were rated as more beautiful. Next, we searched for correlations of beauty ratings and perceptual contrast with statistical properties of abstract artworks (Experiment 2). The participants showed significant preferences for particular image properties. These preferences differed between the clusters of participants. Strikingly, next to color measures like hue, saturation, value and lightness, the recently described Pyramid of Histograms of Orientation Gradients (PHOG) self-similarity value seems to be a predictor for aesthetic appreciation of abstract artworks. We speculate that the shift in evaluation in Experiment 1 was, at least in part, based on low-level adaptation to some of the statistical image properties analyzed in Experiment 2. In conclusion, our findings demonstrate that the perception of beauty in abstract artworks is altered after exposure to beautiful or non-beautiful images and correlates with particular image properties, especially color measures and self-similarity. PMID:24711791

  7. Beauty in abstract paintings: Perceptual contrast and statistical properties

    Directory of Open Access Journals (Sweden)

    Birgit eMallon

    2014-03-01

    Full Text Available In this study, we combined the behavioral and objective approach in the field of empirical aesthetics. First, we studied the perception of beauty by investigating shifts in evaluation on perceived beauty of abstract artworks (Experiment 1. Because the participants showed heterogeneous individual preferences for the paintings, we divided them into seven clusters for the test. The experiment revealed a clear pattern of perceptual contrast. The perceived beauty of abstract paintings increased after exposure to paintings that were rated as less beautiful, and it decreased after exposure to paintings that were rated as more beautiful. Next, we searched for correlations of beauty ratings and perceptual contrast with statistical properties of abstract artworks (Experiment 2. The participants showed significant preferences for certain image properties. These preferences differed between the clusters of participants. Strikingly, next to color measures like hue, saturation, value and lightness, the recently described PHOG self-similarity value seems to be a predictor for aesthetic appreciation of abstract artworks. We speculate that the shift in evaluation in Experiment 1 was, at least in part, based on low-level adaptation to some of the statistical image properties analyzed in Experiment 2. In conclusion, our findings demonstrate that the perception of beauty in abstract artworks is altered after exposure to beautiful or non-beautiful images and correlates with particular image properties, especially color measures and self-similarity.

  8. Perceptual and Acoustic Pecularities of Advertising Slogans (Melodic Aspect

    Directory of Open Access Journals (Sweden)

    Natalya Yuryevna Sorokoletova

    2015-12-01

    Full Text Available The article presents the results of a phonetic experiment on melodic features of public service advertising (PSA. The objective of PSA is to raise awareness, influence and change public attitudes and behavior towards a social issue. Being an integral part of modern society, PSA has its linguistic and extra-linguistic peculiarities. The goal of the investigation was to establish basic tones for an English-speaking public service advertising slogan, test their acoustic measures and describe the role they play in pragmatic function realization. The work is based on the material of 75English language public service advertising videos. The PSA slogans were selected, manipulated and tested. The perceptual analysis revealed the most productive (high fall, low fall, low rise and less productive (fall-rise and rise-fall nuclear tones of advertising slogans. The acoustic measures included: voice fundamental frequency maximal (F0 max, voice fundamental frequency minimal (F0 min, voice fundamental frequency mean (F0 and pitch range (F0 range. The analysis conducted with the help of Praat and Speech Analyzer computer software applications supported these observations. The comparative analysis of the results of the perceptual and acoustic experiments allowed to identify the basic melodic features involved in the implementation of the pragmatic effect of PSA slogans.

  9. Color-Based Image Retrieval Using Perceptually Modified Hausdorff Distance

    Directory of Open Access Journals (Sweden)

    Park BoGun

    2008-01-01

    Full Text Available In most content-based image retrieval systems, the color information is extensively used for its simplicity and generality. Due to its compactness in characterizing the global information, a uniform quantization of colors, or a histogram, has been the most commonly used color descriptor. However, a cluster-based representation, or a signature, has been proven to be more compact and theoretically sound than a histogram for increasing the discriminatory power and reducing the gap between human perception and computer-aided retrieval system. Despite of these advantages, only few papers have broached dissimilarity measure based on the cluster-based nonuniform quantization of colors. In this paper, we extract the perceptual representation of an original color image, a statistical signature by modifying general color signature, which consists of a set of points with statistical volume. Also we present a novel dissimilarity measure for a statistical signature called Perceptually Modified Hausdorff Distance (PMHD that is based on the Hausdorff distance. In the result, the proposed retrieval system views an image as a statistical signature, and uses the PMHD as the metric between statistical signatures. The precision versus recall results show that the proposed dissimilarity measure generally outperforms all other dissimilarity measures on an unmodified commercial image database.

  10. Color-Based Image Retrieval Using Perceptually Modified Hausdorff Distance

    Directory of Open Access Journals (Sweden)

    Bo Gun Park

    2008-02-01

    Full Text Available In most content-based image retrieval systems, the color information is extensively used for its simplicity and generality. Due to its compactness in characterizing the global information, a uniform quantization of colors, or a histogram, has been the most commonly used color descriptor. However, a cluster-based representation, or a signature, has been proven to be more compact and theoretically sound than a histogram for increasing the discriminatory power and reducing the gap between human perception and computer-aided retrieval system. Despite of these advantages, only few papers have broached dissimilarity measure based on the cluster-based nonuniform quantization of colors. In this paper, we extract the perceptual representation of an original color image, a statistical signature by modifying general color signature, which consists of a set of points with statistical volume. Also we present a novel dissimilarity measure for a statistical signature called Perceptually Modified Hausdorff Distance (PMHD that is based on the Hausdorff distance. In the result, the proposed retrieval system views an image as a statistical signature, and uses the PMHD as the metric between statistical signatures. The precision versus recall results show that the proposed dissimilarity measure generally outperforms all other dissimilarity measures on an unmodified commercial image database.

  11. Perceptually Valid Facial Expressions for Character-Based Applications

    Directory of Open Access Journals (Sweden)

    Ali Arya

    2009-01-01

    Full Text Available This paper addresses the problem of creating facial expression of mixed emotions in a perceptually valid way. The research has been done in the context of a “game-like” health and education applications aimed at studying social competency and facial expression awareness in autistic children as well as native language learning, but the results can be applied to many other applications such as games with need for dynamic facial expressions or tools for automating the creation of facial animations. Most existing methods for creating facial expressions of mixed emotions use operations like averaging to create the combined effect of two universal emotions. Such methods may be mathematically justifiable but are not necessarily valid from a perceptual point of view. The research reported here starts by user experiments aiming at understanding how people combine facial actions to express mixed emotions, and how the viewers perceive a set of facial actions in terms of underlying emotions. Using the results of these experiments and a three-dimensional emotion model, we associate facial actions to dimensions and regions in the emotion space, and create a facial expression based on the location of the mixed emotion in the three-dimensional space. We call these regionalized facial actions “facial expression units.”

  12. Toward an efficient objective metric based on perceptual criteria

    Science.gov (United States)

    Quintard, Ludovic; Larabi, Mohamed-Chaker; Fernandez-Maloigne, Christine

    2008-01-01

    Quality assessment is a very challenging problem and will still as is since it is difficult to define universal tools. So, subjective assessment is one adapted way but it is tedious, time consuming and needs normalized room. Objective metrics can be with reference, with reduced reference and with no-reference. This paper presents a study carried out for the development of a no-reference objective metric dedicated to the quality evaluation of display devices. Initially, a subjective study has been devoted to this problem by asking a representative panel (15 male and 15 female; 10 young adults, 10 adults and 10 seniors) to answer questions regarding their perception of several criteria for quality assessment. These quality factors were hue, saturation, contrast and texture. This aims to define the importance of perceptual criteria in the human judgment of quality. Following the study, the factors that impact the quality evaluation of display devices have been proposed. The development of a no-reference objective metric has been performed by using statistical tools allowing to separate the important axes. This no-reference metric based on perceptual criteria by integrating some specificities of the human visual system (HVS) has a high correlation with the subjective data.

  13. Determination of CRT color gamut boundaries in perceptual color space

    Science.gov (United States)

    Wang, Yong; Xu, Haisong

    2005-02-01

    CRT color gamut boundaries can be determined by two steps workflow. Firstly, the display should be calibrated with the method recommended by CIE to characterize the relationship between CIE tristimulus values and DAC values. The nonlinear relationship of each electronic channel between the color of the radiant output of CRT displays and the digital DAC values can be characterized accurately with GOG model using parameters of gain, offset, and gamma. Secondly, color gamut boundary can be determined using a fast and accurate algorithm. Generally, in a color space, any chosen degree of lightness will reduce that space to a plane. The color gamut on this equal-lightness plane can be transformed into RGB DAC value space. Since locations on the edges and surfaces of RGB DAC value space will correspond colors with relatively high saturation, the boundary of the curved surface in RGB DAC value space can be quickly computed for certain lightness. The accurate color gamut is obtained by mapping this boundary over to such a perceptual color space as CIELAB or CIELUV uniform color space. The key issue of this algorithm is to compute the equal-lightness curved surface in RGB DAC value space. The resolution of device gamut description depends on the number of segments that the lightness axis is separated into in the perceptual color space.

  14. Comparison of perceptual color spaces for natural image segmentation tasks

    Science.gov (United States)

    Correa-Tome, Fernando E.; Sanchez-Yanez, Raul E.; Ayala-Ramirez, Victor

    2011-11-01

    Color image segmentation largely depends on the color space chosen. Furthermore, spaces that show perceptual uniformity seem to outperform others due to their emulation of the human perception of color. We evaluate three perceptual color spaces, CIELAB, CIELUV, and RLAB, in order to determine their contribution to natural image segmentation and to identify the space that obtains the best results over a test set of images. The nonperceptual color space RGB is also included for reference purposes. In order to quantify the quality of resulting segmentations, an empirical discrepancy evaluation methodology is discussed. The Berkeley Segmentation Dataset and Benchmark is used in test series, and two approaches are taken to perform the experiments: supervised pixelwise classification using reference colors, and unsupervised clustering using k-means. A majority filter is used as a postprocessing stage, in order to determine its contribution to the result. Furthermore, a comparison of elapsed times taken by the required transformations is included. The main finding of our study is that the CIELUV color space outperforms the other color spaces in both discriminatory performance and computational speed, for the average case.

  15. Bayesian hierarchical grouping: Perceptual grouping as mixture estimation.

    Science.gov (United States)

    Froyen, Vicky; Feldman, Jacob; Singh, Manish

    2015-10-01

    We propose a novel framework for perceptual grouping based on the idea of mixture models, called Bayesian hierarchical grouping (BHG). In BHG, we assume that the configuration of image elements is generated by a mixture of distinct objects, each of which generates image elements according to some generative assumptions. Grouping, in this framework, means estimating the number and the parameters of the mixture components that generated the image, including estimating which image elements are "owned" by which objects. We present a tractable implementation of the framework, based on the hierarchical clustering approach of Heller and Ghahramani (2005). We illustrate it with examples drawn from a number of classical perceptual grouping problems, including dot clustering, contour integration, and part decomposition. Our approach yields an intuitive hierarchical representation of image elements, giving an explicit decomposition of the image into mixture components, along with estimates of the probability of various candidate decompositions. We show that BHG accounts well for a diverse range of empirical data drawn from the literature. Because BHG provides a principled quantification of the plausibility of grouping interpretations over a wide range of grouping problems, we argue that it provides an appealing unifying account of the elusive Gestalt notion of Prägnanz. PMID:26322548

  16. Easy moves: Perceptual fluency facilitates approach-related action.

    Science.gov (United States)

    Carr, Evan W; Rotteveel, Mark; Winkielman, Piotr

    2016-06-01

    It is well established that processing fluency impacts preference judgments and physiological reactions indicative of affect. Yet, little is known about how fluency influences motivation-related action. Here, we offer a novel demonstration that fluency facilitates action-tendencies related to approach. Four experiments investigated this action effect, its boundary conditions, and concomitant affective responses. Experiment 1 found faster approach movements (reaction times [RTs] to initiate arm flexion) to perceptually fluent stimuli when participants acted to rapidly classify stimuli as either "good" or "bad." Experiment 2 eliminated this fluency effect on action when participants performed nonaffective classifications ("living" or "nonliving"), even though fluency robustly enhanced liking judgments. Experiment 3 demonstrated that fluency can also facilitate approach action that is not immediate, as long as the delayed action involves affective classification. This experiment also found that fluent stimuli elicit genuine hedonic responses, as reflected in facial electromyography (fEMG) activity over zygomaticus "smiling" muscle. Experiment 4 replicated the physiological (fEMG) evidence for hedonic responses to fluent stimuli, but similar to Experiment 2, we observed no fluency effects on actions involving nonaffective classification. The current studies offer the first evidence that perceptual fluency can facilitate approach-related movements, when such movements are embedded in the context of affective decisions. Generally, these results suggest that variations in processing dynamics can flexibly and implicitly shape action-tendencies. (PsycINFO Database Record PMID:26751628

  17. Different coding strategies for the perception of stable and changeable facial attributes

    Science.gov (United States)

    Taubert, Jessica; Alais, David; Burr, David

    2016-01-01

    Perceptual systems face competing requirements: improving signal-to-noise ratios of noisy images, by integration; and maximising sensitivity to change, by differentiation. Both processes occur in human vision, under different circumstances: they have been termed priming, or serial dependencies, leading to positive sequential effects; and adaptation or habituation, which leads to negative sequential effects. We reasoned that for stable attributes, such as the identity and gender of faces, the system should integrate: while for changeable attributes like facial expression, it should also engage contrast mechanisms to maximise sensitivity to change. Subjects viewed a sequence of images varying simultaneously in gender and expression, and scored each as male or female, and happy or sad. We found strong and consistent positive serial dependencies for gender, and negative dependency for expression, showing that both processes can operate at the same time, on the same stimuli, depending on the attribute being judged. The results point to highly sophisticated mechanisms for optimizing use of past information, either by integration or differentiation, depending on the permanence of that attribute. PMID:27582115

  18. Different coding strategies for the perception of stable and changeable facial attributes.

    Science.gov (United States)

    Taubert, Jessica; Alais, David; Burr, David

    2016-01-01

    Perceptual systems face competing requirements: improving signal-to-noise ratios of noisy images, by integration; and maximising sensitivity to change, by differentiation. Both processes occur in human vision, under different circumstances: they have been termed priming, or serial dependencies, leading to positive sequential effects; and adaptation or habituation, which leads to negative sequential effects. We reasoned that for stable attributes, such as the identity and gender of faces, the system should integrate: while for changeable attributes like facial expression, it should also engage contrast mechanisms to maximise sensitivity to change. Subjects viewed a sequence of images varying simultaneously in gender and expression, and scored each as male or female, and happy or sad. We found strong and consistent positive serial dependencies for gender, and negative dependency for expression, showing that both processes can operate at the same time, on the same stimuli, depending on the attribute being judged. The results point to highly sophisticated mechanisms for optimizing use of past information, either by integration or differentiation, depending on the permanence of that attribute. PMID:27582115

  19. Newborn Infants' Sensitivity to Perceptual Cues to Lexical and Grammatical Words.

    Science.gov (United States)

    Shi, Rushen; Werker, Janet F.; Morgan, James L.

    1999-01-01

    Presented neonates with lexical and grammatical words prepared from natural maternal speech. Found that neonates could categorically discriminate the sets based on a constellation of perceptual cues that distinguished them. Suggested that this ability to discriminate words on basis of multiple acoustic/phonological cues provides a perceptual base…

  20. Attention Set for Number: Expectation and Perceptual Load in Inattentional Blindness

    Science.gov (United States)

    White, Rebekah C.; Davies, Anne Aimola

    2008-01-01

    Inattentional blindness is the failure to detect unexpected events when attention is otherwise engaged. Previous research indicates that inattentional blindness increases as perceptual demands intensify. The authors present 6 cuing experiments that manipulated both the perceptual demands of a primary letter-naming task and the expectations of the…

  1. Visual perception of procedural textures: identifying perceptual dimensions and predicting generation models.

    Science.gov (United States)

    Liu, Jun; Dong, Junyu; Cai, Xiaoxu; Qi, Lin; Chantler, Mike

    2015-01-01

    Procedural models are widely used in computer graphics for generating realistic, natural-looking textures. However, these mathematical models are not perceptually meaningful, whereas the users, such as artists and designers, would prefer to make descriptions using intuitive and perceptual characteristics like "repetitive," "directional," "structured," and so on. To make up for this gap, we investigated the perceptual dimensions of textures generated by a collection of procedural models. Two psychophysical experiments were conducted: free-grouping and rating. We applied Hierarchical Cluster Analysis (HCA) and Singular Value Decomposition (SVD) to discover the perceptual features used by the observers in grouping similar textures. The results suggested that existing dimensions in literature cannot accommodate random textures. We therefore utilized isometric feature mapping (Isomap) to establish a three-dimensional perceptual texture space which better explains the features used by humans in texture similarity judgment. Finally, we proposed computational models to map perceptual features to the perceptual texture space, which can suggest a procedural model to produce textures according to user-defined perceptual scales. PMID:26106895

  2. Perceptual Mapping Software as a Tool for Facilitating School-Based Consultation

    Science.gov (United States)

    Rush, S. Craig; Kalish, Ashley; Wheeler, Joanna

    2013-01-01

    Perceptual mapping is a systematic method for collecting, analyzing, and presenting group perceptions that is potentially useful in consultation. With input and feedback from a consultee group, perceptual mapping allows the consultant to capture the group's collective perceptions and display them as an organized image that may foster…

  3. Visual perception of procedural textures: identifying perceptual dimensions and predicting generation models.

    Directory of Open Access Journals (Sweden)

    Jun Liu

    Full Text Available Procedural models are widely used in computer graphics for generating realistic, natural-looking textures. However, these mathematical models are not perceptually meaningful, whereas the users, such as artists and designers, would prefer to make descriptions using intuitive and perceptual characteristics like "repetitive," "directional," "structured," and so on. To make up for this gap, we investigated the perceptual dimensions of textures generated by a collection of procedural models. Two psychophysical experiments were conducted: free-grouping and rating. We applied Hierarchical Cluster Analysis (HCA and Singular Value Decomposition (SVD to discover the perceptual features used by the observers in grouping similar textures. The results suggested that existing dimensions in literature cannot accommodate random textures. We therefore utilized isometric feature mapping (Isomap to establish a three-dimensional perceptual texture space which better explains the features used by humans in texture similarity judgment. Finally, we proposed computational models to map perceptual features to the perceptual texture space, which can suggest a procedural model to produce textures according to user-defined perceptual scales.

  4. Is the Linguistic Content of Speech Less Salient than Its Perceptual Features in Autism?

    Science.gov (United States)

    Jarvinen-Pasley, Anna; Pasley, John; Heaton, Pamela

    2008-01-01

    Open-ended tasks are rarely used to investigate cognition in autism. No known studies have directly examined whether increased attention to the perceptual level of speech in autism might contribute to a reduced tendency to process language meaningfully. The present study investigated linguistic versus perceptual speech processing preferences.…

  5. The Effects of Perceptual Similarity and Category Membership on Early Word-Referent Identification

    Science.gov (United States)

    Arias-Trejo, Natalia; Plunkett, Kim

    2010-01-01

    We investigated the impact of perceptual and categorical relatedness between a target and a distracter object on early referent identification in infants and adults. In an intermodal preferential looking (IPL) task, participants looked at a target object paired with a distracter object that could be perceptually similar or dissimilar and drawn…

  6. Comparison of Perceptual Signs of Voice before and after Vocal Hygiene Program in Adults with Dysphonia

    Directory of Open Access Journals (Sweden)

    Seyyedeh Maryam khoddami

    2011-12-01

    Full Text Available Background and Aim: Vocal abuse and misuse are the most frequent causes of voice disorders. Consequently some therapy is needed to stop or modify such behaviors. This research was performed to study the effectiveness of vocal hygiene program on perceptual signs of voice in people with dysphonia.Methods: A Vocal hygiene program was performed to 8 adults with dysphonia for 6 weeks. At first, Consensus Auditory- Perceptual Evaluation of Voice was used to assess perceptual signs. Then the program was delivered, Individuals were followed in second and forth weeks visits. In the last session, perceptual assessment was performed and individuals’ opinions were collected. Perceptual findings were compared before and after the therapy.Results: After the program, mean score of perceptual assessment decreased. Mean score of every perceptual sign revealed significant difference before and after the therapy (p≤0.0001. «Loudness» had maximum score and coordination between speech and respiration indicated minimum score. All participants confirmed efficiency of the therapy.Conclusion: The vocal hygiene program improves all perceptual signs of voice although not equally. This deduction is confirmed by both clinician-based and patient-based assessments. As a result, vocal hygiene program is necessary for a comprehensive voice therapy but is not solely effective to resolve all voice problems.

  7. Student Performance in Water Pouring and Balance Beam Tasks: Effect of Manipulation of Perceptual Field Factor.

    Science.gov (United States)

    Niaz, Mansoor

    1988-01-01

    The effect of manipulation of the perceptual field factors on undergraduate student performance in proportional reasoning tasks was investigated. Evidence was found to support the hypothesis that the manipulation of the perceptual field factor can affect student performance. Reports data correlated with the Group Embedded-Figures Test. (CW)

  8. The Development of a Visual-Perceptual Chemistry Specific (VPCS) Assessment Tool

    Science.gov (United States)

    Oliver-Hoyo, Maria; Sloan, Caroline

    2014-01-01

    The development of the Visual-Perceptual Chemistry Specific (VPCS) assessment tool is based on items that align to eight visual-perceptual skills considered as needed by chemistry students. This tool includes a comprehensive range of visual operations and presents items within a chemistry context without requiring content knowledge to solve…

  9. Producing American English Vowels during Vocal Tract Growth: A Perceptual Categorization Study of Synthesized Vowels

    Science.gov (United States)

    Menard, Lucie; Davis, Barbara L.; Boe, Louis-Jean; Roy, Johanna-Pascale

    2009-01-01

    Purpose: To consider interactions of vocal tract change with growth and perceived output patterns across development, the influence of nonuniform vocal tract growth on the ability to reach acoustic-perceptual targets for English vowels was studied. Method: Thirty-seven American English speakers participated in a perceptual categorization…

  10. A Model for the Transfer of Perceptual-Motor Skill Learning in Human Behaviors

    Science.gov (United States)

    Rosalie, Simon M.; Muller, Sean

    2012-01-01

    This paper presents a preliminary model that outlines the mechanisms underlying the transfer of perceptual-motor skill learning in sport and everyday tasks. Perceptual-motor behavior is motivated by performance demands and evolves over time to increase the probability of success through adaptation. Performance demands at the time of an event…

  11. Object-Based Attention Overrides Perceptual Load to Modulate Visual Distraction

    Science.gov (United States)

    Cosman, Joshua D.; Vecera, Shaun P.

    2012-01-01

    The ability to ignore task-irrelevant information and overcome distraction is central to our ability to efficiently carry out a number of tasks. One factor shown to strongly influence distraction is the perceptual load of the task being performed; as the perceptual load of task-relevant information processing increases, the likelihood that…

  12. Subjective Confidence in Perceptual Judgments: A Test of the Self-Consistency Model

    Science.gov (United States)

    Koriat, Asher

    2011-01-01

    Two questions about subjective confidence in perceptual judgments are examined: the bases for these judgments and the reasons for their accuracy. Confidence in perceptual judgments has been claimed to rest on qualitatively different processes than confidence in memory tasks. However, predictions from a self-consistency model (SCM), which had been…

  13. Real-Time Strategy Video Game Experience and Visual Perceptual Learning.

    Science.gov (United States)

    Kim, Yong-Hwan; Kang, Dong-Wha; Kim, Dongho; Kim, Hye-Jin; Sasaki, Yuka; Watanabe, Takeo

    2015-07-22

    Visual perceptual learning (VPL) is defined as long-term improvement in performance on a visual-perception task after visual experiences or training. Early studies have found that VPL is highly specific for the trained feature and location, suggesting that VPL is associated with changes in the early visual cortex. However, the generality of visual skills enhancement attributable to action video-game experience suggests that VPL can result from improvement in higher cognitive skills. If so, experience in real-time strategy (RTS) video-game play, which may heavily involve cognitive skills, may also facilitate VPL. To test this hypothesis, we compared VPL between RTS video-game players (VGPs) and non-VGPs (NVGPs) and elucidated underlying structural and functional neural mechanisms. Healthy young human subjects underwent six training sessions on a texture discrimination task. Diffusion-tensor and functional magnetic resonance imaging were performed before and after training. VGPs performed better than NVGPs in the early phase of training. White-matter connectivity between the right external capsule and visual cortex and neuronal activity in the right inferior frontal gyrus (IFG) and anterior cingulate cortex (ACC) were greater in VGPs than NVGPs and were significantly correlated with RTS video-game experience. In both VGPs and NVGPs, there was task-related neuronal activity in the right IFG, ACC, and striatum, which was strengthened after training. These results indicate that RTS video-game experience, associated with changes in higher-order cognitive functions and connectivity between visual and cognitive areas, facilitates VPL in early phases of training. The results support the hypothesis that VPL can occur without involvement of only visual areas. Significance statement: Although early studies found that visual perceptual learning (VPL) is associated with involvement of the visual cortex, generality of visual skills enhancement by action video-game experience

  14. Role of bimodal stimulation for auditory-perceptual skills development in children with a unilateral cochlear implant.

    Science.gov (United States)

    Marsella, P; Giannantonio, S; Scorpecci, A; Pianesi, F; Micardi, M; Resca, A

    2015-12-01

    This is a prospective randomised study that evaluated the differences arising from a bimodal stimulation compared to a monaural electrical stimulation in deaf children, particularly in terms of auditory-perceptual skills development. We enrolled 39 children aged 12 to 36 months, suffering from severe-to-profound bilateral sensorineural hearing loss with residual hearing on at least one side. All were unilaterally implanted: 21 wore only the cochlear implant (CI) (unilateral CI group), while the other 18 used the CI and a contralateral hearing aid at the same time (bimodal group). They were assessed with a test battery designed to appraise preverbal and verbal auditory-perceptual skills immediately before and 6 and 12 months after implantation. No statistically significant differences were observed between groups at time 0, while at 6 and 12 months children in the bimodal group had better scores in each test than peers in the unilateral CI group. Therefore, although unilateral deafness/hearing does not undermine hearing acuity in normal listening, the simultaneous use of a CI and a contralateral hearing aid (binaural hearing through a bimodal stimulation) provides an advantage in terms of acquisition of auditory-perceptual skills, allowing children to achieve the basic milestones of auditory perception faster and in greater number than children with only one CI. Thus, "keeping awake" the contralateral auditory pathway, albeit not crucial in determining auditory acuity, guarantees benefits compared with the use of the implant alone. These findings provide initial evidence to establish shared guidelines for better rehabilitation of patients undergoing unilateral cochlear implantation, and add more evidence regarding the correct indications for bilateral cochlear implantation. PMID:26900251

  15. The development of race-based perceptual categorization: skin color dominates early category judgments.

    Science.gov (United States)

    Dunham, Yarrow; Stepanova, Elena V; Dotsch, Ron; Todorov, Alexander

    2015-05-01

    Prior research on the development of race-based categorization has concluded that children understand the perceptual basis of race categories from as early as age 4 (e.g. Aboud, 1988). However, such work has rarely separated the influence of skin color from other physiognomic features considered by adults to be diagnostic of race categories. In two studies focusing on Black-White race categorization judgments in children between the ages of 4 and 9, as well as in adults, we find that categorization decisions in early childhood are determined almost entirely by attention to skin color, with attention to other physiognomic features exerting only a small influence on judgments as late as middle childhood. We further find that when skin color cues are largely eliminated from the stimuli, adults readily shift almost entirely to focus on other physiognomic features. However, 6- and 8-year-old children show only a limited ability to shift attention to facial physiognomy and so perform poorly on the task. These results demonstrate that attention to 'race' in younger children is better conceptualized as attention to skin color, inviting a reinterpretation of past work focusing on children's race-related cognition. PMID:25154647

  16. Own- and other-race face scanning in infants: implications for perceptual narrowing.

    Science.gov (United States)

    Xiao, Wen S; Quinn, Paul C; Pascalis, Olivier; Lee, Kang

    2014-02-01

    The present study investigated how 6- and 9-month-old Caucasian infants scan Caucasian and Chinese dynamic faces using eye-tracking methodology. Analyses of looking times revealed that with increased age, infants decreased their looking time to other-race noses, while maintaining their looking time for own-race noses. From 6 to 9 months, infants increased their looking time for the eyes of both races of faces. Analyses of scan paths showed that infants were no more likely to shift their fixation between the eyes of own-race faces than other-race faces. Similarity between participants' scan paths suggested that facial information was collected more efficiently for own- versus other-race faces at 9 months of age. Combined with previous eye-tracking studies of infants' face scanning (Liu et al. [2011] Journal of Experimental Child Psychology, 108, 180-189; Wheeler et al. [2011] PLoS ONE, 6, e18621. doi: 10.1371/journal.pone.0018621; Xiao et al. [2013] International Journal of Behavioral Development, 37, 100-105), the findings are interpreted in the context of perceptual narrowing and suggest differential contributions of visual experience, facial physiognomy, and culture in accounting for similarity and difference in infants scanning of own- and other-race faces. PMID:24415549

  17. Relative Forest for Visual Attribute Prediction.

    Science.gov (United States)

    Li, Shaoxin; Shan, Shiguang; Yan, Shuicheng; Chen, Xilin

    2016-09-01

    Accurate prediction of the visual attributes is significant in various recognition tasks. For many visual attributes, while it is very difficult to describe the exact degrees of their presences, by comparing the pairs of samples, the relative ordering of presences may be easily figured out. Based on this observation, instead of considering such attribute as binary attribute, the relative attribute method learns a ranking function for each attribute to provide more accurate and informative prediction results. In this paper, we also explore pairwise ranking for visual attribute prediction and propose to improve the relative attribute method in two aspects. First, we propose a relative tree method, which can achieve more accurate ranking in case of nonlinearly distributed visual data. Second, by resorting to randomization and ensemble learning, the relative tree method is extended to the relative forest method to further boost the accuracy and simultaneously reduce the computational cost. To validate the effectiveness of the proposed methods, we conduct extensive experiments on four databases: PubFig, OSR, FGNET, and WebFace. The results show that the proposed relative forest method not only outperforms the original relative attribute method, but also achieve the state-of-the-art accuracy for ordinal visual attribute prediction. PMID:27323363

  18. Developmental Characteristics of African American and Caribbean Black Adolescents’ Attributions Regarding Discrimination

    OpenAIRE

    Seaton, Eleanor K.; Caldwell, Cleopatra H.; Sellers, Robert M.; Jackson, James S.

    2010-01-01

    The present study examined discrimination attributions in the psychological well-being of Black adolescents. Findings are based on a representative sample of 810 African American and 360 Caribbean Black youth, aged 13 to 17, who participated in the National Survey of American Life (NSAL). Youth completed measures of perceived discrimination, discrimination attributions, depressive symptoms, self-esteem and life satisfaction. Approximately half the youth attributed discrimination to race/ethni...

  19. Perpetrator characteristics and blame attributions in a stranger rape situation

    OpenAIRE

    Strömwall, Leif A.; Sara Landström; Helen Alfredsson

    2014-01-01

    Both real-life events and research show that rape victims are sometimes blamed for their victimization. The effect of perpetrator characteristics on victim blaming has rarely been studied. In an experiment using a community sample (N = 161), we investigated the effect of the perpetrator's previous conviction and age, as well as participants' gender and belief in a just world (BJW) on blame attributions using a vignette methodology. It was predicted that less victim blame and more perpetrator ...

  20. Video Games as a Means to Reduce Age-Related Cognitive Decline: Attitudes, Compliance, and Effectiveness

    OpenAIRE

    Boot, Walter R.; Michael eChampion; Daniel Patrick Blakely; Timothy eWright; Dustin eSouders; Neil eCharness

    2013-01-01

    Recent research has demonstrated broad benefits of video game play to perceptual and cognitive abilities. These broad improvements suggest that video game-based cognitive interventions may be ideal to combat the many perceptual and cognitive declines associated with advancing age. Furthermore, game interventions have the potential to induce higher rates of intervention compliance compared to other cognitive interventions as they are assumed to be inherently enjoyable and motivating. We exp...

  1. Attributional analysis of chronic illness outcomes.

    Science.gov (United States)

    Lowery, B J; Jacobsen, B S

    1985-01-01

    The Weiner et al. attribution model has generated a great deal of research on attributions for success and failure in academic achievement situations. Studies of success and failure attributions in real-life situations of high personal concern are limited. If the attribution model is to lead to a general theory of motivation, such tests in real-life situations are critical. In this study, causal attributions for success and failure outcomes of chronically ill patients were examined. Results indicated at least partial support for the model. Patients tended to attribute success internally and failure externally, but stability and expectations were not linked in this sample. Moreover, a tendency to respond with no cause to an open-ended measure and to hold little commitment to any causes on a closed-ended measure was characteristic of failure subjects. PMID:3844736

  2. Attributional and relational processing in pigeons

    Directory of Open Access Journals (Sweden)

    Dennis eGarlick

    2011-02-01

    Full Text Available Six pigeons were trained using a matching-to-sample procedure where sample and rewarded comparisons matched on both attributional (color and relational (horizontal or vertical orientation dimensions. Probes then evaluated the pigeons’ preference to comparisons that varied in these dimensions. A strong preference was found for the attribute of color. The discrimination was not found to transfer to novel colors, however, suggesting that a general color rule had not been learned. Further, when color could not be used to guide responding, some influence of other attributional cues such as shape, but not relational cues, was found. We conclude that pigeons based their performance on attributional properties of but not on relational properties between elements in our matching-to-sample procedure.. Future studies should look at examining other attributes to compare attributional versus relational processing.

  3. Lightning Strikes and Attribution of Climatic Change

    CERN Document Server

    Webster, Anthony J

    2015-01-01

    Using lightning strikes as an example, two possible schemes are discussed for the attribution of changes in event frequency to climate change, and estimating the cost associated with them. The schemes determine the fraction of events that should be attributed to climatic change, and the fraction that should be attributed to natural chance. They both allow for the expected increase in claims and the fluctuations about this expected value. Importantly, the attribution fraction proposed in the second of these schemes is necessarily different to that found in epidemiological studies. This ensures that the statistically expected fraction of attributed claims is correctly equal to the expected increase in claims. The analysis of lightning data highlights two particular difficulties with data-driven, as opposed to modeled, attribution studies. The first is the possibility of unknown "confounding" variables that can influence the strike frequency. This is partly accounted for here by considering the influence of temp...

  4. Young Children's References to Temporal Attributes of Allegedly Experienced Events in the Course of Forensic Interviews

    Science.gov (United States)

    Orbach, Yael; Lamb, Michael E.

    2007-01-01

    Developmental differences in references to temporal attributes of allegedly experienced events were examined in 250 forensic interviews of 4- to 10-year-old alleged victims of sexual abuse. Children's ages, the specific temporal attributes referenced, and the types of memory tapped by the interviewers' questions significantly affected the quantity…

  5. Graph matching and clustering using kernel attributes

    OpenAIRE

    Lozano Ortega, Miguel Ángel; Escolano Ruiz, Francisco

    2013-01-01

    In this paper, we exploit graph kernels for graph matching and clustering. Firstly, we analyze different kinds of graph kernels in order to extract from them attributes to be used as a similarity measure between nodes of non-attributed graphs. Next, such attributes are embedded in a graph-matching cost function, through a probabilistic framework, and we evaluate their performance within a graph-matching algorithm. Secondly, we propose a method for obtaining a representative prototype from a s...

  6. Clothing Style Recognition using Fashion Attribute Detection

    OpenAIRE

    Guang-Lu Sun; Xiao Wu; Hong-Han Chen; Qiang Peng

    2015-01-01

    In this paper, a new framework is proposed for clothing style recognition in natural scenes. Clothing region is first detected through the fusion of super-pixel segmentation, saliency detection and Gaussian Mixture Model (GMM). Next, a group of fashion attribute detectors are trained to get the likelihood of each attribute in the clothing image. Finally, the correlation matrix between clothing styles and fashion attributes is adopted to predict the clothing style. For evaluation, we collect a...

  7. Second Attribute Algorithm Based on Tree Expression

    Institute of Scientific and Technical Information of China (English)

    Su-Qing Han; Jue Wang

    2006-01-01

    One view of finding a personalized solution of reduct in an information system is grounded on the viewpoint that attribute order can serve as a kind of semantic representation of user requirements. Thus the problem of finding personalized solutions can be transformed into computing the reduct on an attribute order. The second attribute theorem describes the relationship between the set of attribute orders and the set of reducts, and can be used to transform the problem of searching solutions to meet user requirements into the problem of modifying reduct based on a given attribute order. An algorithm is implied based on the second attribute theorem, with computation on the discernibility matrix. Its time complexity is O(n2 × m) (n is the number of the objects and m the number of the attributes of an information system).This paper presents another effective second attribute algorithm for facilitating the use of the second attribute theorem,with computation on the tree expression of an information system. The time complexity of the new algorithm is linear in n. This algorithm is proved to be equivalent to the algorithm on the discernibility matrix.

  8. Machine Learning Based on Attribute Interactions

    OpenAIRE

    Jakulin, Aleks

    2005-01-01

    Two attributes $A$ and $B$ are said to interact when it helps to observe the attribute values of both attributes together. This is an example of a $2$-way interaction. In general, a group of attributes ${\\cal X}$ is involved in a $k$-way interaction when we cannot reconstruct their relationship merely with $\\ell$-way interactions, $\\ell < k$. These two definitions formalize the notion of an interaction in a nutshell. An additional notion is the one of context. We interpret context as just...

  9. Clothing Style Recognition using Fashion Attribute Detection

    Directory of Open Access Journals (Sweden)

    Guang-Lu Sun

    2015-08-01

    Full Text Available In this paper, a new framework is proposed for clothing style recognition in natural scenes. Clothing region is first detected through the fusion of super-pixel segmentation, saliency detection and Gaussian Mixture Model (GMM. Next, a group of fashion attribute detectors are trained to get the likelihood of each attribute in the clothing image. Finally, the correlation matrix between clothing styles and fashion attributes is adopted to predict the clothing style. For evaluation, we collect a dataset for clothing style recognition which contains 5 styles and 14 fashion attributes. Extensive experiments demonstrate that the proposed framework has a promising ability to recognize the clothing style.

  10. Perceptual learning for treating amblyopia in children based on activation of visual signal pathway Relationship of curative effects and time

    Institute of Scientific and Technical Information of China (English)

    Weimin Liu; Jiang Shen; Jianzhong Huang; Yan Luo; Hongting Liu

    2008-01-01

    BACKGROUND: Conventional methods (such as occlusion therapy, fine manipulation, complementary, and alternative medicine) take effects slowly, are time and labor consuming, and have uncertain curative effects in the treatment of amblyopia. Perceptual learning, a new method for treating amblyopia, improves the ability to process signals from the cerebral optic nerve system by specific visual stimulation and visual learning, as well as activation of the visual signal pathway utilizing brain nervous system plasticity.OBJECTIVE: This study investigated and evaluated the curative effects of perceptual learning, which can directionally increase brain plasticity, on the treatment of amblyopia in children. The relationship between curative effect and time was also analyzed.DESIGN: A self-control experiment. SETTING: Visual Science and Optometry Center, People's Hospital of Guangxi Zhuang Autonomous Region. PARTICIPANTS: A total of 125 amblyopic children (250 amblyopic eyes), 73 males, 52 females, averaging (6 ± 2) years of age, received treatment at the Visual Science and Optometry Center, People's Hospital of Guangxi Zhuang Autonomous Region between September 2006 and February 2007 and were recruited for this study. All children presented with no structural disease of the eyeballs. Written informed consent for therapeutic regiments was obtained from each child's parent. The protocol received approval from the Hospital's Ethics Committee. METHODS: Visual function was tested with a perceptual learning system (Research Center for Human Health and Development of Sun Yat-sen University, National Engineering Technique Research Center for Medical Care Implement) for visual noise, position noise, contour discrimination, contrast sensitivity, grating stereogram, and random-dot fusion. These tests helped to evaluate the efficiency of visual information processing of these children, and to determine the degree of defects of the optic nerve cells and the connections of visual

  11. The source dilemma hypothesis: Perceptual uncertainty contributes to musical emotion.

    Science.gov (United States)

    Bonin, Tanor L; Trainor, Laurel J; Belyk, Michel; Andrews, Paul W

    2016-09-01

    Music can evoke powerful emotions in listeners. Here we provide the first empirical evidence that the principles of auditory scene analysis and evolutionary theories of emotion are critical to a comprehensive theory of musical emotion. We interpret these data in light of a theoretical framework termed "the source dilemma hypothesis," which predicts that uncertainty in the number, identity or location of sound objects elicits unpleasant emotions by presenting the auditory system with an incoherent percept, thereby motivating listeners to resolve the auditory ambiguity. We describe two experiments in which source location and timbre were manipulated to change uncertainty in the auditory scene. In both experiments, listeners rated tonal and atonal melodies with congruent auditory scene cues as more pleasant than melodies with incongruent auditory scene cues. These data suggest that music's emotive capacity relies in part on the perceptual uncertainty it produces regarding the auditory scene. PMID:27318599

  12. The memorability and discriminability of primitive perceptual units in infancy.

    Science.gov (United States)

    Adler, S A; Rovee-Collier, C

    1994-02-01

    Three-month-olds were operantly trained to kick to move a block mobile that displayed a horizontal and a vertical line ("textons") arranged as L, T, or + on each side. Delayed recognition was tested either 0, 1, 3, 5, 7, or 9 days later with either the same or a different display. Infants failed to discriminate between Ls and Ts after delays longer than 1 hr but discriminated both from +s, which contains an additional texton (the line crossing), after delays as long as 7 days but not 9. Also, they remembered +s longer than Ls and Ts. These data indicate that the same primitive perceptual units that mediate adult texture segregation are differentially discriminated and differentially memorable in early infancy. PMID:8303829

  13. Relationship between uniform connectedness and proximity in perceptual grouping

    Institute of Scientific and Technical Information of China (English)

    HAN; Shihui; (韩世辉); Glyn; W.; Humphreys

    2003-01-01

    Palmer and Rock proposed that uniform connectedness (UC) occurs prior to classical Gestalt factors to define the primitive units for visual perception. Han, Humphreys and Chen, however, found that grouping by proximity can take place as quickly as that based on UC in a letter discrimination task. The present study employed a letter detection task to examine the relationship between UC and proximity grouping in 3 experiments. We showed that reaction times to targets defined by proximity or UC were equally fast when one or two global objects were presented in the visual field. However, as the number of global objects was increased, responses were faster to targets defined by UC than to targets defined by proximity. In addition, the advantage of UC over proximity was not affected by the space between global objects. The results suggest that UC was more effective than proximity in forming perceptual units under multiple object conditions. Possible reasons for this finding are discussed.

  14. Perceptual Effects of Dynamic Range Compression in Popular Music Recordings

    DEFF Research Database (Denmark)

    Hjortkjær, Jens; Walther-Hansen, Mads

    2014-01-01

    There is a widespread belief that the increasing use of dynamic range compression in music mastering (the loudnesswar) deteriorates sound quality but experimental evidence of perceptual effects is lacking. In this study, normal hearing listeners were asked to evaluate popular music recordings in...... original versions and in remastered versions with higher levels of dynamic range compression. Surprisingly, we found no evidence of preference for the less compressed music. We also failed to find differences in ratings of perceived "depth" between the original and more compressed audio. A low degree of...... response consistency between different presentations of the same music suggests that listeners are less sensitive to even high levels of dynamic range compression than often argued....

  15. The role of selective attention in perceptual and affective priming

    Science.gov (United States)

    Stone, M.; Ladd, S. L.; Gabrieli, J. D.

    2000-01-01

    Two kinds of perceptual priming (word identification and word fragment completion), as well as preference priming (that may rely on special affective mechanisms) were examined after participants either read or named the colors of words and nonwords at study. Participants named the colors of words more slowly than the colors of nonwords, indicating that lexical processing of the words occurred at study. Nonetheless, priming on all three tests was lower after color naming than after reading, despite evidence of lexical processing during color naming shown by slower responses to words than to nonwords. These results indicate that selective attention to (rather than the mere processing of) letter string identity at study is important for subsequent repetition priming.

  16. The irradiated larynx and voice: a perceptual study.

    Science.gov (United States)

    Stoicheff, M L; Ciampi, A; Passi, J E; Fredrickson, J M

    1983-12-01

    The voices of patients with laryngeal cancer following a specific radiotherapy regimen were subjected to perceptual evaluation. Interval scaling of the severity of perceived dysphonia was completed for the voices of male patients sampled before and 1 year following radiation therapy and for a set of male controls. Eight listeners did this quantitative rating and also specified the predominant quality in each voice. The results indicated that the degree of dysphonia in the pretreatment group was highest. Radiotherapy decreased this dysphonia but not to the point that posttreatment voices were indistinguishable from those of normal subjects. Also, the voice qualities of laryngeal cancer patients shifted toward those of the control group following radiotherapy with over one half of the irradiated patients judged to have rough or normal qualities. PMID:6668937

  17. Perceptual and physiological responses to Jackson Pollock’s fractals

    Directory of Open Access Journals (Sweden)

    Richard Taylor

    2011-06-01

    Full Text Available Fractals have been very successful in quantifying the visual complexity exhibited by many natural patterns, and have captured the imagination of scientists and artists alike. Our research has shown that the poured patterns of the American abstract painter Jackson Pollock are also fractal. This discovery raises an intriguing possibility – are the visual characteristics of fractals responsible for the long-term appeal of Pollock’s work? To address this question, we have conducted ten years of scientific investigation of human response to fractals and here we present, for the first time, a review of this research that examines the inter-relationship between the various results. The investigations include eye-tracking, visual preference, skin conductance, and EEG measurement techniques. We discuss the artistic implications of the positive perceptual and physiological responses to fractal patterns.

  18. Perceptual and Physiological Responses to Jackson Pollock's Fractals.

    Science.gov (United States)

    Taylor, Richard P; Spehar, Branka; Van Donkelaar, Paul; Hagerhall, Caroline M

    2011-01-01

    Fractals have been very successful in quantifying the visual complexity exhibited by many natural patterns, and have captured the imagination of scientists and artists alike. Our research has shown that the poured patterns of the American abstract painter Jackson Pollock are also fractal. This discovery raises an intriguing possibility - are the visual characteristics of fractals responsible for the long-term appeal of Pollock's work? To address this question, we have conducted 10 years of scientific investigation of human response to fractals and here we present, for the first time, a review of this research that examines the inter-relationship between the various results. The investigations include eye tracking, visual preference, skin conductance, and EEG measurement techniques. We discuss the artistic implications of the positive perceptual and physiological responses to fractal patterns. PMID:21734876

  19. Perceptual Decision-Making as Probabilistic Inference by Neural Sampling.

    Science.gov (United States)

    Haefner, Ralf M; Berkes, Pietro; Fiser, József

    2016-05-01

    We address two main challenges facing systems neuroscience today: understanding the nature and function of cortical feedback between sensory areas and of correlated variability. Starting from the old idea of perception as probabilistic inference, we show how to use knowledge of the psychophysical task to make testable predictions for the influence of feedback signals on early sensory representations. Applying our framework to a two-alternative forced choice task paradigm, we can explain multiple empirical findings that have been hard to account for by the traditional feedforward model of sensory processing, including the task dependence of neural response correlations and the diverging time courses of choice probabilities and psychophysical kernels. Our model makes new predictions and characterizes a component of correlated variability that represents task-related information rather than performance-degrading noise. It demonstrates a normative way to integrate sensory and cognitive components into physiologically testable models of perceptual decision-making. PMID:27146267

  20. Reflexive and automatic violence: a function of aberrant perceptual inhibition

    Directory of Open Access Journals (Sweden)

    Golembiewski, Jan A.

    2014-12-01

    Full Text Available It is commonly assumed that psychiatric violence is motivated by delusions, but here the concept of a reversed impetus is explored, to understand whether delusions are formed as ad-hoc or post-hoc rationalizations of behaviour or in advance of the actus reus. The reflexive violence model proposes that perceptual stimuli has motivational power and this may trigger unwanted actions and hallucinations. The model is based on the theory of ecological perception, where opportunities enabled by an object are cues to act. As an apple triggers a desire to eat, a gun triggers a desire to shoot. These affordances (as they are called are part of the perceptual apparatus, they allow the direct recognition of objects – and in emergencies they enable the fastest possible reactions. Even under normal circumstances, the presence of a weapon will trigger inhibited violent impulses. The presence of a victim will also, but under normal circumstances, these affordances don’t become violent because negative action impulses are totally inhibited, whereas in psychotic illness, negative action impulses are treated as emergencies and bypass frontal inhibitory circuits. What would have been object recognition becomes a blind automatic action. A range of mental illnesses can cause inhibition to be bypassed. At its most innocuous, this causes both simple hallucinations (where the motivational power of an object is misattributed. But ecological perception may have the power to trigger serious violence also –a kind that’s devoid of motives or planning and is often shrouded in amnesia or post-rational delusions

  1. Applying perceptual and adaptive learning techniques for teaching introductory histopathology

    Directory of Open Access Journals (Sweden)

    Sally Krasne

    2013-01-01

    Full Text Available Background: Medical students are expected to master the ability to interpret histopathologic images, a difficult and time-consuming process. A major problem is the issue of transferring information learned from one example of a particular pathology to a new example. Recent advances in cognitive science have identified new approaches to address this problem. Methods: We adapted a new approach for enhancing pattern recognition of basic pathologic processes in skin histopathology images that utilizes perceptual learning techniques, allowing learners to see relevant structure in novel cases along with adaptive learning algorithms that space and sequence different categories (e.g. diagnoses that appear during a learning session based on each learner′s accuracy and response time (RT. We developed a perceptual and adaptive learning module (PALM that utilized 261 unique images of cell injury, inflammation, neoplasia, or normal histology at low and high magnification. Accuracy and RT were tracked and integrated into a "Score" that reflected students rapid recognition of the pathologies and pre- and post-tests were given to assess the effectiveness. Results: Accuracy, RT and Scores significantly improved from the pre- to post-test with Scores showing much greater improvement than accuracy alone. Delayed post-tests with previously unseen cases, given after 6-7 weeks, showed a decline in accuracy relative to the post-test for 1 st -year students, but not significantly so for 2 nd -year students. However, the delayed post-test scores maintained a significant and large improvement relative to those of the pre-test for both 1 st and 2 nd year students suggesting good retention of pattern recognition. Student evaluations were very favorable. Conclusion: A web-based learning module based on the principles of cognitive science showed an evidence for improved recognition of histopathology patterns by medical students.

  2. Prism adaptation contrasts perceptual habituation for repetitive somatosensory stimuli.

    Science.gov (United States)

    Torta, D M; Tatu, M K; Cotroneo, D; Alamia, A; Folegatti, A; Trojan, J

    2016-03-01

    Prism adaptation (PA) is a non-invasive procedure that requires performing a visuo-motor pointing task while wearing prism goggles inducing a visual displacement of the pointed target. This procedure involves a reorganization of sensorimotor coordination, and induces long-lasting effects on numerous higher-order cognitive functions in healthy volunteers and neglect patients. Prismatic displacement (PD) of the visual field can be induced when prisms are worn but no sensorimotor task is required. In this case, it is unlikely that any subsequent reorganization takes place. The effects of PD are short-lived in the sense that they last as long as prisms are worn. In this study we aimed, to the best of our knowledge for the first time, at investigating whether PA and PD induce changes in the perception of intensity of nociceptive and non- nociceptive somatosensory stimuli. We induced, in healthy volunteers, PD (experiment 1), or PA (experiment 2) and asked participants to rate the intensity of the stimuli applied to the hand undergoing the visuo-proprioceptive conflict (experiment 1) or adaptation (experiment 2). Our results indicate that: 1) the visuo-proprioceptive conflict induced by PD does not reduce the perceived intensity of the stimuli, 2) PA prevents perceptual habituation for both nociceptive and non-nociceptive somatosensory stimuli. Moreover, to investigate the possible underlying mechanisms of the effects of PA we conducted a third experiment in which stimuli were applied both at the adapted and the non-adapted hand. In line with the results of experiment 2, we found that perceptual habituation was prevented for stimuli applied onto the adapted hand. Moreover, we observed the same finding for stimuli applied onto the non-adapted hand. This result suggests that the detention of habituation is not merely driven by changes in spatial attention allocation. Taken together, these data indicate that prisms can affect the perceived intensity of somatosensory stimuli

  3. Perceptual other-race training reduces implicit racial bias.

    Directory of Open Access Journals (Sweden)

    Sophie Lebrecht

    Full Text Available BACKGROUND: Implicit racial bias denotes socio-cognitive attitudes towards other-race groups that are exempt from conscious awareness. In parallel, other-race faces are more difficult to differentiate relative to own-race faces--the "Other-Race Effect." To examine the relationship between these two biases, we trained Caucasian subjects to better individuate other-race faces and measured implicit racial bias for those faces both before and after training. METHODOLOGY/PRINCIPAL FINDINGS: Two groups of Caucasian subjects were exposed equally to the same African American faces in a training protocol run over 5 sessions. In the individuation condition, subjects learned to discriminate between African American faces. In the categorization condition, subjects learned to categorize faces as African American or not. For both conditions, both pre- and post-training we measured the Other-Race Effect using old-new recognition and implicit racial biases using a novel implicit social measure--the "Affective Lexical Priming Score" (ALPS. Subjects in the individuation condition, but not in the categorization condition, showed improved discrimination of African American faces with training. Concomitantly, subjects in the individuation condition, but not the categorization condition, showed a reduction in their ALPS. Critically, for the individuation condition only, the degree to which an individual subject's ALPS decreased was significantly correlated with the degree of improvement that subject showed in their ability to differentiate African American faces. CONCLUSIONS/SIGNIFICANCE: Our results establish a causal link between the Other-Race Effect and implicit racial bias. We demonstrate that training that ameliorates the perceptual Other-Race Effect also reduces socio-cognitive implicit racial bias. These findings suggest that implicit racial biases are multifaceted, and include malleable perceptual skills that can be modified with relatively little training.

  4. Perceptual filling-in of stereoscopically presented targets Preenchimento perceptual de estímulos estereoscópicos

    Directory of Open Access Journals (Sweden)

    Márcia Furukawa Couto

    2007-02-01

    Full Text Available PURPOSE: To investigate the influence of parametric variation on the filling-in latency of stereoscopically presented stimuli. METHODS: Anaglyphs were created using two circular patches of 0.3º diameter, 0.5º disparity and 6º eccentricity from fixation point. Targets were presented at the visual field midline, 90º and 270º positions, with crossed and uncrossed disparity. The time elapsed for disappearance of the target under voluntary steady fixation was computed. Eighteen subjects tested. RESULTS: There was no significant difference between crossed and uncrossed disparities, nor between near or far from the vertical horopter line. The significant difference was between upper and lower visual field positions. CONCLUSION: The results show that: (i stereoscopic presentation does not influence the target filling-in latency; (ii differences between dorsal and ventral visual stream might influence target filling-in latency.OBJETIVO: Investigar a influência da variação de parâmetros estereoscópicos na latência de preenchimento perceptual de estímulos 3D. MÉTODOS: Criados anáglifos com dois discos de 0,3º de diâmetro, 0,5º de disparidade e 6º de excentricidade do ponto central de fixação. Estímulos foram apresentados na linha central do campo visual, nas posições 90º e 270º, com disparidade cruzada e não cruzada. Registrado o tempo gasto para o preenchimento do estímulo sob fixação estável. Testados dezoito indivíduos. RESULTADOS: Não houve diferença significativa entre as disparidades cruzada e não cruzada, nem entre perto e longe da linha do horóptero vertical. Houve diferença significativa entre posição superior e inferior do campo visual. CONCLUSÕES: Os resultados mostram que: (i a apresentação estereoscópica não tem influência na latência de preenchimento perceptual, (ii diferenças entre o sistema visual dorsal e ventral podem influenciar a latência de preenchimento perceptual.

  5. Mental imagery of speech: linking motor and perceptual systems through internal simulation and estimation

    Directory of Open Access Journals (Sweden)

    Xing Tian

    2012-11-01

    Full Text Available The neural basis of mental imagery has been investigated by localizing the underlying neural networks, mostly in motor and perceptual systems, separately. However, how modality-specific representations are top-down induced and how the action and perception systems interact in the context of mental imagery is not well understood. Imagined speech production (‘articulation imagery’, which induces the kinesthetic feeling of articulator movement and its auditory consequences, provides a new angle because of the concurrent involvement of motor and perceptual systems. On the basis of previous findings in mental imagery of speech, we argue for the following regarding the induction mechanisms of mental imagery and the interaction between motor and perceptual systems: (1 Two distinct top-down mechanisms, memory retrieval and motor simulation, exist to induce estimation in perceptual systems. (2 Motor simulation is sufficient to internally induce the representation of perceptual changes that would be caused by actual movement (perceptual associations; however, this simulation process only has modulatory effects on the perception of external stimuli, which critically depends on context and task demands. Considering the proposed simulation-estimation processes as common mechanisms for interaction between motor and perceptual systems, we outline how mental imagery (of speech relates to perception and production, and how these hypothesized mechanisms might underpin certain neural disorders.

  6. Stimulus familiarity affects perceptual restoration in the European starling (Sturnus vulgaris.

    Directory of Open Access Journals (Sweden)

    Folkert Seeba

    Full Text Available BACKGROUND: Humans can easily restore a speech signal that is temporally masked by an interfering sound (e.g., a cough masking parts of a word in a conversation, and listeners have the illusion that the speech continues through the interfering sound. This perceptual restoration for human speech is affected by prior experience. Here we provide evidence for perceptual restoration in complex vocalizations of a songbird that are acquired by vocal learning in a similar way as humans learn their language. METHODOLOGY/PRINCIPAL FINDINGS: European starlings were trained in a same/different paradigm to report salient differences between successive sounds. The birds' response latency for discriminating between a stimulus pair is an indicator for the salience of the difference, and these latencies can be used to evaluate perceptual distances using multi-dimensional scaling. For familiar motifs the birds showed a large perceptual distance if discriminating between song motifs that were muted for brief time periods and complete motifs. If the muted periods were filled with noise, the perceptual distance was reduced. For unfamiliar motifs no such difference was observed. CONCLUSIONS/SIGNIFICANCE: The results suggest that starlings are able to perceptually restore partly masked sounds and, similarly to humans, rely on prior experience. They may be a suitable model to study the mechanism underlying experience-dependent perceptual restoration.

  7. Predictors of Attributional Style Change in Children

    Science.gov (United States)

    Gibb, Brandon E.; Alloy, Lauren B.; Walshaw, Patricia D.; Comer, Jonathan S.; Shen, Gail H. C.; Villari, Annette G.

    2006-01-01

    A number of studies have supported the hypothesis that negative attributional styles may confer vulnerability to the development of depression. The goal of this study was to explore factors that may contribute to the development of negative attributional styles in children. As hypothesized, elevated levels of depressive symptoms and hopelessness…

  8. Attributes of an Effective Feedback Process

    Science.gov (United States)

    Journal of Staff Development, 2015

    2015-01-01

    Not all feedback is created equal. It is actually quite uneven in its design and effectiveness. Feedback forms typically used by educators and the feedback process used to support learning have markedly different attributes. Understanding the key attributes of effective feedback is important for those involved in the feedback process. The tools…

  9. Pretest probability assessment derived from attribute matching

    Directory of Open Access Journals (Sweden)

    Hollander Judd E

    2005-08-01

    Full Text Available Abstract Background Pretest probability (PTP assessment plays a central role in diagnosis. This report compares a novel attribute-matching method to generate a PTP for acute coronary syndrome (ACS. We compare the new method with a validated logistic regression equation (LRE. Methods Eight clinical variables (attributes were chosen by classification and regression tree analysis of a prospectively collected reference database of 14,796 emergency department (ED patients evaluated for possible ACS. For attribute matching, a computer program identifies patients within the database who have the exact profile defined by clinician input of the eight attributes. The novel method was compared with the LRE for ability to produce PTP estimation Results In the validation set, attribute matching produced 267 unique PTP estimates [median PTP value 6%, 1st–3rd quartile 1–10%] compared with the LRE, which produced 96 unique PTP estimates [median 24%, 1st–3rd quartile 10–30%]. The areas under the receiver operating characteristic curves were 0.74 (95% CI 0.65 to 0.82 for the attribute matching curve and 0.68 (95% CI 0.62 to 0.77 for LRE. The attribute matching system categorized 1,670 (24%, 95% CI = 23–25% patients as having a PTP Conclusion Attribute matching estimated a very low PTP for ACS in a significantly larger proportion of ED patients compared with a validated LRE.

  10. An Attributional Approach to Counselor Attractiveness.

    Science.gov (United States)

    Hackman, Hollis W.; Claiborn, Charles D.

    1982-01-01

    Examined two components of counselor attractiveness--perceived similarity and liking--in a comparison of two theoretical approaches to attractiveness and influence in counseling--the referent power hypothesis and an attributional approach. Results generally support the attributional approach over the reference power hypothesis. (Author)

  11. Sex Differences in Attributions of Juvenile Delinquency.

    Science.gov (United States)

    Sagatun, Inger J.

    This paper is an application of attribution theory to the processing of juvenile delinquents in an attempt to understand the differential treatment of female and male offenders within the juvenile justice system. The paper explores the attributions of juvenile delinquency both by male and female minors, by male and female parents, and by male and…

  12. Extreme events: The art of attribution

    Science.gov (United States)

    Otto, Friederike E. L.

    2016-04-01

    A high-impact weather event that occurred at the end of a decade of weather extremes led to the emergence of extreme event attribution science. The challenge is now to move on to assessing the actual risks, rather than simply attributing meteorological variables to climate change.

  13. Neutron activation analysis helps in picture attribution

    International Nuclear Information System (INIS)

    The neutron activation analysis application for obtaining the data useful for proper attribution of paintings has been presented on the base of several examples. The identification on this way of dye elements, pigments and other painting materials is an important element among the physico-chemical methods helping the attribution procedure of old painting objects

  14. Attributional Style and the Freshman Writer.

    Science.gov (United States)

    Gordon, Douglas K.; Mercier, Judith D.

    Martin Seligman's psychology research on depression, published in 7 books and hundreds of articles, shows a correlation between attributional style and depression. "Explanatory style" is another term nearly synonymous with attributional style, a habitual way to explain, positively or negatively, external events. A "learned" optimist himself,…

  15. Hostile attributional bias and aggressive behavior in global context

    Science.gov (United States)

    Dodge, Kenneth A.; Malone, Patrick S.; Lansford, Jennifer E.; Sorbring, Emma; Skinner, Ann T.; Tapanya, Sombat; Tirado, Liliana Maria Uribe; Zelli, Arnaldo; Alampay, Liane Peña; Al-Hassan, Suha M.; Bacchini, Dario; Bombi, Anna Silvia; Bornstein, Marc H.; Chang, Lei; Deater-Deckard, Kirby; Di Giunta, Laura; Oburu, Paul; Pastorelli, Concetta

    2015-01-01

    We tested a model that children’s tendency to attribute hostile intent to others in response to provocation is a key psychological process that statistically accounts for individual differences in reactive aggressive behavior and that this mechanism contributes to global group differences in children’s chronic aggressive behavior problems. Participants were 1,299 children (mean age at year 1 = 8.3 y; 51% girls) from 12 diverse ecological-context groups in nine countries worldwide, followed across 4 y. In year 3, each child was presented with each of 10 hypothetical vignettes depicting an ambiguous provocation toward the child and was asked to attribute the likely intent of the provocateur (coded as benign or hostile) and to predict his or her own behavioral response (coded as nonaggression or reactive aggression). Mothers and children independently rated the child’s chronic aggressive behavior problems in years 2, 3, and 4. In every ecological group, in those situations in which a child attributed hostile intent to a peer, that child was more likely to report that he or she would respond with reactive aggression than in situations when that same child attributed benign intent. Across children, hostile attributional bias scores predicted higher mother- and child-rated chronic aggressive behavior problems, even controlling for prior aggression. Ecological group differences in the tendency for children to attribute hostile intent statistically accounted for a significant portion of group differences in chronic aggressive behavior problems. The findings suggest a psychological mechanism for group differences in aggressive behavior and point to potential interventions to reduce aggressive behavior. PMID:26170281

  16. Hostile attributional bias and aggressive behavior in global context.

    Science.gov (United States)

    Dodge, Kenneth A; Malone, Patrick S; Lansford, Jennifer E; Sorbring, Emma; Skinner, Ann T; Tapanya, Sombat; Tirado, Liliana Maria Uribe; Zelli, Arnaldo; Alampay, Liane Peña; Al-Hassan, Suha M; Bacchini, Dario; Bombi, Anna Silvia; Bornstein, Marc H; Chang, Lei; Deater-Deckard, Kirby; Di Giunta, Laura; Oburu, Paul; Pastorelli, Concetta

    2015-07-28

    We tested a model that children's tendency to attribute hostile intent to others in response to provocation is a key psychological process that statistically accounts for individual differences in reactive aggressive behavior and that this mechanism contributes to global group differences in children's chronic aggressive behavior problems. Participants were 1,299 children (mean age at year 1 = 8.3 y; 51% girls) from 12 diverse ecological-context groups in nine countries worldwide, followed across 4 y. In year 3, each child was presented with each of 10 hypothetical vignettes depicting an ambiguous provocation toward the child and was asked to attribute the likely intent of the provocateur (coded as benign or hostile) and to predict his or her own behavioral response (coded as nonaggression or reactive aggression). Mothers and children independently rated the child's chronic aggressive behavior problems in years 2, 3, and 4. In every ecological group, in those situations in which a child attributed hostile intent to a peer, that child was more likely to report that he or she would respond with reactive aggression than in situations when that same child attributed benign intent. Across children, hostile attributional bias scores predicted higher mother- and child-rated chronic aggressive behavior problems, even controlling for prior aggression. Ecological group differences in the tendency for children to attribute hostile intent statistically accounted for a significant portion of group differences in chronic aggressive behavior problems. The findings suggest a psychological mechanism for group differences in aggressive behavior and point to potential interventions to reduce aggressive behavior. PMID:26170281

  17. Rapid eye movement sleep dreaming is characterized by uncoupled EEG activity between frontal and perceptual cortical regions.

    Science.gov (United States)

    Corsi-Cabrera, M; Miró, E; del-Río-Portilla, Y; Pérez-Garci, E; Villanueva, Y; Guevara, M A

    2003-04-01

    EEG coherent activity is involved in the binding of spatially separated but temporally correlated stimuli into whole events. Cognitive features of rapid eye movement sleep (REM) dreaming resemble frontal lobe dysfunction. Therefore, temporal coupling of EEG activity between frontal and perceptual regions was analyzed from 10 min prior to dream reports (8 adults) from stage-2 and REM sleep. EEG correlation between frontal and perceptual regions decreased and, among perceptual regions increased during REM. The temporal dissociation of EEG activity between executive and perceptual regions supplies an inadequate mechanism for the binding and interpretation of ongoing perceptual activity resulting in dream bizarreness. PMID:12727188

  18. Action video game play facilitates the development of better perceptual templates.

    Science.gov (United States)

    Bejjanki, Vikranth R; Zhang, Ruyuan; Li, Renjie; Pouget, Alexandre; Green, C Shawn; Lu, Zhong-Lin; Bavelier, Daphne

    2014-11-25

    The field of perceptual learning has identified changes in perceptual templates as a powerful mechanism mediating the learning of statistical regularities in our environment. By measuring threshold-vs.-contrast curves using an orientation identification task under varying levels of external noise, the perceptual template model (PTM) allows one to disentangle various sources of signal-to-noise changes that can alter performance. We use the PTM approach to elucidate the mechanism that underlies the wide range of improvements noted after action video game play. We show that action video game players make use of improved perceptual templates compared with nonvideo game players, and we confirm a causal role for action video game play in inducing such improvements through a 50-h training study. Then, by adapting a recent neural model to this task, we demonstrate how such improved perceptual templates can arise from reweighting the connectivity between visual areas. Finally, we establish that action gamers do not enter the perceptual task with improved perceptual templates. Instead, although performance in action gamers is initially indistinguishable from that of nongamers, action gamers more rapidly learn the proper template as they experience the task. Taken together, our results establish for the first time to our knowledge the development of enhanced perceptual templates following action game play. Because such an improvement can facilitate the inference of the proper generative model for the task at hand, unlike perceptual learning that is quite specific, it thus elucidates a general learning mechanism that can account for the various behavioral benefits noted after action game play. PMID:25385590

  19. Risk attributes theory: Decision making under risk

    DEFF Research Database (Denmark)

    He, Ying; Huang, Ruihua

    2008-01-01

    In this paper, some limitations in the conventional theories and models of the decision making under risk are presented from a new angle. To eliminate those limitations, a theoretical framework is proposed, in which the risk preference relation is constructed on a set of risk attributes instead of...... risky prospects. The axioms are presented to ensure the existence of the representation function for this risk preference relation through employing the Multi-attribute Utility Theory (MAUT). In our framework, we construct a risk decision model with four risk attributes. One of these attributes measured...... by a newly defined attribute measurement, the Relative Maximum Absolute Value (RMAV), can be employed in our model to explain the experimental result more intuitively compared with the overweighting of small probability proposed by Kahneman and Tversky in their Prospect Theory. In addition, the...

  20. Aspects of the relationship between the processing of stimuli in the peripheral perceptual field and in the perceptual central field

    Directory of Open Access Journals (Sweden)

    Mihai Anitei

    2008-01-01

    Full Text Available As humans have limited information processing abilities and rely on three fallible mental functions: perception, attention and memory, the driving error is easy to appear. The purpose of this paper is to highlight the male/female differences in processing the perceptive information from the external stimuli in the peripheral visual field and to demonstrate that the mean of the estimate errors in evaluating the speed and distances in the central visual perceptual field is in inverse ratio to the reaction time value at the visual stimuli from the peripheral driving tasks simulation. Between the variables number of wrong reactions and number of omissions there has been obtained a relatively high negative correlation (r=-0.728, p<0.001. The result has a strong implication in visual stimuli processing during driving tasks.

  1. A Perceptual Motor Intervention Improves Play Behavior In Children With Moderate To Severe Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Brigette Oliver Ryalls

    2016-05-01

    Full Text Available For children with moderate or severe cerebral palsy (CP, a foundational early goal is independent sitting. Sitting offers additional opportunities for object exploration, play and social engagement. The achievement of sitting coincides with important milestones in other developmental areas, such as social engagement with others, understanding of spatial relationships, and the use of both hands to explore objects. These milestones are essential skills necessary for play behavior. However, little is known about how sitting and play behavior might be affected by a physical therapy intervention in children with moderate or severe CP. Therefore, our overall purpose in this study was to determine if sitting skill could be advanced in children with moderate to severe CP using a perceptual motor intervention, and if play skills would change significantly as sitting advanced. Thirty children between the ages of 18 months and 6 years who were able to hold prop sitting for at least 10 seconds were recruited for this study. Outcome measures were the sitting subsection of the Gross Motor Function Measure (GMFM, and the Play Assessment of Children with Motor Impairment (PACMI play assessment scale, which is a modified version of the Play in Early Childhood Evaluation System (PIECES. Significant improvements in GMFM sitting scores (p<0.001 and marginally significant improvement in play assessment scores (p=0.067 were found from pre- to post-intervention. Sitting change explained a significant portion of the variance in play change for children over the age of 3 years, who were more severely affected by CP. The results of this study indicate that advances in sitting skill may be a factor in supporting improvements in functional play, along with age and severity of physical impairment.

  2. A Perceptual Motor Intervention Improves Play Behavior in Children with Moderate to Severe Cerebral Palsy

    Science.gov (United States)

    Ryalls, Brigette O.; Harbourne, Regina; Kelly-Vance, Lisa; Wickstrom, Jordan; Stergiou, Nick; Kyvelidou, Anastasia

    2016-01-01

    For children with moderate or severe cerebral palsy (CP), a foundational early goal is independent sitting. Sitting offers additional opportunities for object exploration, play and social engagement. The achievement of sitting coincides with important milestones in other developmental areas, such as social engagement with others, understanding of spatial relationships, and the use of both hands to explore objects. These milestones are essential skills necessary for play behavior. However, little is known about how sitting and play behavior might be affected by a physical therapy intervention in children with moderate or severe CP. Therefore, our overall purpose in this study was to determine if sitting skill could be advanced in children with moderate to severe CP using a perceptual motor intervention, and if play skills would change significantly as sitting advanced. Thirty children between the ages of 18 months and 6 years who were able to hold prop sitting for at least 10 s were recruited for this study. Outcome measures were the sitting subsection of the Gross Motor Function Measure (GMFM), and the Play Assessment of Children with Motor Impairment play assessment scale, which is a modified version of the Play in Early Childhood Evaluation System. Significant improvements in GMFM sitting scores (p < 0.001) and marginally significant improvement in play assessment scores (p = 0.067) were found from pre- to post-intervention. Sitting change explained a significant portion of the variance in play change for children over the age of 3 years, who were more severely affected by CP. The results of this study indicate that advances in sitting skill may be a factor in supporting improvements in functional play, along with age and severity of physical impairment. PMID:27199868

  3. Control of Perceptual Image Quality Based on PID for Streaming Video

    Institute of Scientific and Technical Information of China (English)

    SONG Jian-xin

    2003-01-01

    Constant levels of perceptual quality of streaming video is what ideall users expect. In most cases, however, they receive time-varying levels of quality of video. In this paper, the author proposes a new control method of perceptual quality in variable bit rate video encoding for streaming video. The image quality calculation based on the perception of human visual systems is presented. Quantization properties of DCT coefficients are analyzed to control effectively. Quantization scale factors are ascertained based on the visual mask effect. A Proportional Integral Difference ( PID ) controller is used to control the image quality. Experimental results show that this method improves the perceptual quality uniformity of encoded video.

  4. Perceptual load affects spatial tuning of neuronal populations in human early visual cortex.

    OpenAIRE

    Haas, B.; Schwarzkopf, D. S.; Anderson, E. J.; Rees, G

    2014-01-01

    Summary Withdrawal of attention from a visual scene as a result of perceptual load modulates overall levels of activity in human visual cortex [1], but its effects on cortical spatial tuning properties are unknown. Here we show attentional load at fixation affects the spatial tuning of population receptive fields (pRFs) in early visual cortex (V1–3) using functional magnetic resonance imaging (fMRI). We found that, compared to low perceptual load, high perceptual load yielded a ‘blurrier’ rep...

  5. Adult age effects in auditory statistical learning

    OpenAIRE

    Neger, T.M.; Rietveld, A.C.M.; Janse, E.

    2015-01-01

    Statistical learning plays a key role in language processing, e.g., for speech segmentation. Older adults have been reported to show less statistical learning on the basis of visual input than younger adults. Given age-related changes in perception and cognition, we investigated whether statistical learning is also impaired in the auditory modality in older compared to younger adults and whether individual learning ability is associated with measures of perceptual (i.e., hearing sensitivity) ...

  6. Impact of Nursery Seeding Density, Nitrogen, and Seedling Age on Yield and Yield Attributes of Fine Rice Impacto de la Densidad de Siembra en Vivero, Nitrógeno, y Edad de Plántula sobre Rendimiento y Atributos de Rendimiento de Arroz Fino

    Directory of Open Access Journals (Sweden)

    Naeem Sarwar

    2011-09-01

    Full Text Available Producing vigorous seedlings and transplanting them at the appropriate age are the most important factors for obtaining high yield in rice (Oryza sativa L. paddy production. The impact of seeding densities, N, and seedling age was evaluated in this experiment after transplanting 10, 20, 30 and 40-d old seedlings raised by using different seeding rates (high and low and N conditions (with and without in the 2008 and 2009 rice growing seasons. The study revealed that 10-d-old nursery seedlings, irrespective of seeding densities and fertilizer application, showed higher yields and yield attributes (productive tillers, plant height, 1000-grain weight, and straw yield, while at later stages significant interaction was observed with nursery management. Transplanting of 20-d older fertile seedlings grown with low seeding density at nursery-bed, resulted in a higher number of productive tillers m-2 (233.3, 227.3, straw yield (11.1, 10.7 t ha-1, and final yield (3.6, 3.4 t ha-1 in both years, 2008 and 2009, respectively. Yield and yield attributes were significantly reduced by transplanting older seedlings grown at high seeding density and without N application at nursery-bed. Minimum productive tillers (165.7, 133, straw yield (8.7, 8.1 t ha-1 and paddy yield (2.0, 1.8 t ha-1 were recorded with transplanting 40-d older seedlings grown at high seeding density and without N application. These findings support the use of young seedling in a system of rice intensification and illustrate that by making a minor additional investment to raise healthy and vigorous seedlings in nursery seed-bed, farmers can improve yields.La producción de plántulas vigorosas y el trasplante en la edad adecuada son los factores más importantes para obtener buenos rendimientos en arroz (Oryza sativa L.. El impacto de la siembra, densidades, N, y edad de las plántulas fue evaluado en este experimento después del trasplante de plántulas de 10, 20, 30 y 40 d cultivadas usando

  7. Alcohol attributable hospitalisations and costs in Ireland, 2000-2004.

    LENUS (Irish Health Repository)

    Martin, J

    2011-05-01

    The aim of this study was to calculate the number and costs of hospital bed-days due to alcohol use in Ireland over the five year period 2000 to 2004. Age and sex specific Irish alcohol-attributable-fractions (AAFs) were developed by combining international risk estimates with Irish consumption data where available; where not available international AAFs were used. These were applied to national datasets to count the number and costs of bed-days wholly caused and prevented by alcohol and that proportion of bed-days that were partially caused and prevented by alcohol. Between 2000 and 2004, alcohol was estimated to have caused 3,428,973 (10.3%) and prevented 529,239 (1.6%) of hospital bed-days, giving a net number of bed-days due to alcohol of 2,899,734 (8.7%). Over this period the hospital inpatient costs attributed to the negative effects of alcohol were 953,126,381 euros, the costs attributed to hospitalisations prevented were 147,968,164 euros; giving net costs of alcohol-attributed bed-days of 805,158,217 euros. Chronic conditions accounted for 3,262,408 (95%) hospital bed-days due to the harmful effects of alcohol. Conditions not wholly due to alcohol accounted for 2,297,412 (67%) hospital bed-days due to the harmful effects of alcohol. The negative impacts of alcohol were greater than previously thought and spread across the whole population.

  8. Continuous carryover of temporal context dissociates response bias from perceptual influence for duration.

    Directory of Open Access Journals (Sweden)

    Martin Wiener

    Full Text Available Recent experimental evidence suggests that the perception of temporal intervals is influenced by the temporal context in which they are presented. A longstanding example is the time-order-error, wherein the perception of two intervals relative to one another is influenced by the order in which they are presented. Here, we test whether the perception of temporal intervals in an absolute judgment task is influenced by the preceding temporal context. Human subjects participated in a temporal bisection task with no anchor durations (partition method. Intervals were demarcated by a Gaussian blob (visual condition or burst of white noise (auditory condition that persisted for one of seven logarithmically spaced sub-second intervals. Crucially, the order in which stimuli were presented was first-order counterbalanced, allowing us to measure the carryover effect of every successive combination of intervals. The results demonstrated a number of distinct findings. First, the perception of each interval was biased by the prior response, such that each interval was judged similarly to the preceding trial. Second, the perception of each interval was also influenced by the prior interval, such that perceived duration shifted away from the preceding interval. Additionally, the effect of decision bias was larger for visual intervals, whereas auditory intervals engendered greater perceptual carryover. We quantified these effects by designing a biologically-inspired computational model that measures noisy representations of time against an adaptive memory prior while simultaneously accounting for uncertainty, consistent with a Bayesian heuristic. We found that our model could account for all of the effects observed in human data. Additionally, our model could only accommodate both carryover effects when uncertainty and memory were calculated separately, suggesting separate neural representations for each. These findings demonstrate that time is susceptible to

  9. Comparison of Voice Perceptual Charactheristics between Speech - Language Pathologists', Dysphonic and Normal Voiced Adult's View

    Directory of Open Access Journals (Sweden)

    Seyyedeh Maryam khoddami

    2010-06-01

    Full Text Available Background and Aim: In recent years, several tools for assessment of quality of patient life have been designed especially for dysphonics. Nowadays, we have useful assessments in health system that are refered for numerous clinical decisions. In this way, this investigation compares clinician and patient perception in dysphonic and normal voiced for first time.Methods: This study was carried out on 30 dysphonic and 30 subjects with normal voice. Their age, sex and job were same. In two groups, Consensus Auditory – Perceptual Evaluation of Voice (CAPE-V was used for evaluation of clinician perception and Voice Handicap Index - 30 (VHI-30 for assessment of patient perception. After collecting data, they were analyzed by Mann- witney and Wilcoxon tests.Results: The research revealed that mean of total and each section score of VHI-30 have significant difference between dysphonic and control group (p<0.01. Comparison of total and every parameter score of CAPE-V and speed also indicated significant difference between two groups (p<0.01. Study of reliability shows weak reliability (r=0.34 between clinician and patient perception of voice in dysphonics.Conclusion: Dysphonic patients percept their voice problem different and severe rather than clinicians that shows physical, psychological and social affects of dysphonia. This research confirms that patient – based assessment of voice is necessary to be part of common assessments of dysphonia.

  10. Smoking-Attributable Mortality, Morbidity, and Economic Costs (SAMMEC) - Smoking-Attributable Expenditures (SAE)

    Data.gov (United States)

    U.S. Department of Health & Human Services — 2005-2009. SAMMEC - Smoking-Attributable Mortality, Morbidity, and Economic Costs. Smoking-attributable expenditures (SAEs) are excess health care expenditures...

  11. Smoking-Attributable Mortality, Morbidity, and Economic Costs (SAMMEC) - Smoking Attributable Mortality (SAM)

    Data.gov (United States)

    U.S. Department of Health & Human Services — 2005-2009. SAMMEC - Smoking-Attributable Mortality, Morbidity, and Economic Costs. Smoking attributable mortality (SAM) is the number of deaths caused by cigarette...

  12. Smoking-Attributable Mortality, Morbidity, and Economic Costs (SAMMEC) - Smoking-Attributable Mortality (SAM)

    Data.gov (United States)

    U.S. Department of Health & Human Services — 2005-2009. SAMMEC - Smoking-Attributable Mortality, Morbidity, and Economic Costs. Smoking-attributable mortality (SAM) is the number of deaths caused by cigarette...

  13. The Depressive Attributions Questionnaire (DAQ): Development of a Short Self-Report Measure of Depressogenic Attributions

    OpenAIRE

    Kleim, B; Gonzalo, D; Ehlers, A

    2011-01-01

    A depressogenic attributional style, i.e., internal, stable and global causal interpretations of negative events, is a stable vulnerability factor for depression. Current measures of pessimistic attributional style can be time-consuming to complete, and some are designed for specific use with student populations. We developed and validated a new short questionnaire suitable for the measurement of depressogenic attributions in clinical settings, the Depressive Attributions Questionnaire (DAQ)....

  14. Predicting brain activation patterns associated with individual lexical concepts based on five sensory-motor attributes.

    Science.gov (United States)

    Fernandino, Leonardo; Humphries, Colin J; Seidenberg, Mark S; Gross, William L; Conant, Lisa L; Binder, Jeffrey R

    2015-09-01

    While major advances have been made in uncovering the neural processes underlying perceptual representations, our grasp of how the brain gives rise to conceptual knowledge remains relatively poor. Recent work has provided strong evidence that concepts rely, at least in part, on the same sensory and motor neural systems through which they were acquired, but it is still unclear whether the neural code for concept representation uses information about sensory-motor features to discriminate between concepts. In the present study, we investigate this question by asking whether an encoding model based on five semantic attributes directly related to sensory-motor experience - sound, color, visual motion, shape, and manipulation - can successfully predict patterns of brain activation elicited by individual lexical concepts. We collected ratings on the relevance of these five attributes to the meaning of 820 words, and used these ratings as predictors in a multiple regression model of the fMRI signal associated with the words in a separate group of participants. The five resulting activation maps were then combined by linear summation to predict the distributed activation pattern elicited by a novel set of 80 test words. The encoding model predicted the activation patterns elicited by the test words significantly better than chance. As expected, prediction was successful for concrete but not for abstract concepts. Comparisons between encoding models based on different combinations of attributes indicate that all five attributes contribute to the representation of concrete concepts. Consistent with embodied theories of semantics, these results show, for the first time, that the distributed activation pattern associated with a concept combines information about different sensory-motor attributes according to their respective relevance. Future research should investigate how additional features of phenomenal experience contribute to the neural representation of conceptual

  15. Construct Validity of Attributional Style: Modeling Context-Dependent Item Sets in the Attributional Style Questionnaire.

    Science.gov (United States)

    Higgins, N. C.; Zumbo, Bruno D.; Hay, Jana L.

    1999-01-01

    Confirmatory factor analysis of data from 1,346 respondents to the Attributional Style Questionnaire (ASQ) (C. Peterson and others, 1982) reveals that adequate fit is provided by a three-factor attributional style model that includes context-dependent item sets. Results suggest that there is no such thing as a nonsituational attributional style.…

  16. Fundamental attributes of water-conducting features

    International Nuclear Information System (INIS)

    The fundamental attributes of water-conducting features are discussed in two parts. The first part is a generic discussion of the attributes of water conducting features, and the second part illustrates some of these attributes using site-specific cases in various geologic media. The description of water-conducting features may use either geologic or statistical geometric approaches or a mixture of the two. More often, however, correlations of geologic and hydraulic properties are not completely adequate. The spatial structure of water conducting features affects strongly their importance for performance assessment. (author)

  17. Concert hall acoustics: Repertoire, listening position, and individual taste of the listeners influence the qualitative attributes and preferences.

    Science.gov (United States)

    Lokki, Tapio; Pätynen, Jukka; Kuusinen, Antti; Tervo, Sakari

    2016-07-01

    Some studies of concert hall acoustics consider the acoustics in a hall as a single entity. Here, it is shown that the acoustics vary between different seats, and the choice of music also influences the perceived acoustics. The presented study compared the acoustics of six unoccupied concert halls with extensive listening tests, applying two different music excerpts on three different seats. Twenty eight assessors rated the halls according to the subjective preference of the assesors and individual attributes with a paired comparison method. Results show that assessors can be classified into two preference groups, which prioritize different perceptual factors. In addition, the individual attributes elicited by assessors were clustered into three latent classes. PMID:27475177

  18. Occipital MEG Activity in the Early Time Range (<300 ms) Predicts Graded Changes in Perceptual Consciousness

    DEFF Research Database (Denmark)

    Andersen, Lau Møller; Pedersen, Michael Nygaard; Sandberg, Kristian;

    2016-01-01

    Two electrophysiological components have been extensively investigated as candidate neural correlates of perceptual consciousness: An early, occipitally realized component occurring 130-320 ms after stimulus onset and a late, frontally realized component occurring 320-510 ms after stimulus onset...... when decoding perceptual consciousness from the 2 components using sources from occipital and frontal lobes. We found that occipital sources during the early time range were significantly more accurate in decoding perceptual consciousness than frontal sources during both the early and late time ranges....... These results are the first of its kind where the predictive values of the 2 components are quantitatively compared, and they provide further evidence for the primary importance of occipital sources in realizing perceptual consciousness. The results have important consequences for current theories of...

  19. Human perceptual deficits as factors in computer interface test and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bowser, S.E.

    1992-06-01

    Issues related to testing and evaluating human computer interfaces are usually based on the machine rather than on the human portion of the computer interface. Perceptual characteristics of the expected user are rarely investigated, and interface designers ignore known population perceptual limitations. For these reasons, environmental impacts on the equipment will more likely be defined than will user perceptual characteristics. The investigation of user population characteristics is most often directed toward intellectual abilities and anthropometry. This problem is compounded by the fact that some deficits capabilities tend to be found in higher-than-overall population distribution in some user groups. The test and evaluation community can address the issue from two primary aspects. First, assessing user characteristics should be extended to include tests of perceptual capability. Secondly, interface designs should use multimode information coding.

  20. Through the eyes of an expert: Role and development of perceptual skills

    NARCIS (Netherlands)

    Jarodzka, Halszka

    2011-01-01

    Jarodzka, H. (2010, 11 November). Through the eyes of an expert: Role and development of perceptual skills. Presentation at the Learning & Cognition meeting, Heerlen, The Netherlands: Open University of the Netherlands.