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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 faces

  2. Perceptual and social attributes underlining age-related preferences for faces

    Directory of Open Access Journals (Sweden)

    Hanni SM Kiiski

    2016-08-01

    Full Text Available 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 ageing, with an age-related bias in favouring 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

  3. PERCEPTUAL MAPPING BASED ON IDIOSYNCRATIC SETS OF ATTRIBUTES

    NARCIS (Netherlands)

    STEENKAMP, JBEM; VANTRIJP, HCM; TENBERGE, JMF

    1994-01-01

    The authors describe a compositional perceptual mapping procedure, unrestricted attribute-elicitation mapping (UAM), which allows consumers to describe and rate the brands in their own terminology and thus relaxes the restrictive assumptions of traditional compositional mapping techniques regarding

  4. 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

  5. Perceptual-Motor Attributes of Mentally Retarded Youth.

    Science.gov (United States)

    Cratty, Bryant J.

    To evaluate six perceptual-motor attributes of trainable and educable mentally retarded children, a battery of tests was constructed which included body perception, gross agility, balance, locomotor ability, throwing, and tracking; 83 retarded subjects provided reliability data, and their scores, with those of 120 additional subjects, provided…

  6. Perceptual and motor attribute ratings for 559 object concepts.

    Science.gov (United States)

    Amsel, Ben D; Urbach, Thomas P; Kutas, Marta

    2012-12-01

    To understand how and when object knowledge influences the neural underpinnings of language comprehension and linguistic behavior, it is critical to determine the specific kinds of knowledge that people have. To extend the normative data currently available, we report a relatively more comprehensive set of object attribute rating norms for 559 concrete object nouns, each rated on seven attributes corresponding to sensory and motor modalities-color, motion, sound, smell, taste, graspability, and pain-in addition to familiarity (376 raters, M = 23 raters per item). The mean ratings were subjected to principal-components analysis, revealing two primary dimensions plausibly interpreted as relating to survival. We demonstrate the utility of these ratings in accounting for lexical and semantic decision latencies. These ratings should prove useful for the design and interpretation of experimental tests of conceptual and perceptual object processing.

  7. Age-related changes in selective attention and perceptual load during visual search.

    Science.gov (United States)

    Madden, David J; Langley, Linda K

    2003-03-01

    Three visual search experiments were conducted to test the hypothesis that age differences in selective attention vary as a function of perceptual load (E. A. Maylor & N. Lavie, 1998). Under resource-limited conditions (Experiments 1 and 2), the distraction from irrelevant display items generally decreased as display size (perceptual load) increased. This perceptual load effect was similar for younger and older adults, contrary to the findings of Maylor and Lavie. Distraction at low perceptual loads appeared to reflect both general and specific inhibitory mechanisms. Under more data-limited conditions (Experiment 3), an age-related decline in selective attention was evident, but the age difference was not attributable to capacity limitations as predicted by the perceptual load theory.

  8. O Integrality of Perceptual Attributes Determined by Sound Source and Filter.

    Science.gov (United States)

    Li, Xiaofeng

    The production of a complex sound can be viewed as a sequential operation of sound production components: Power excites a sound source that produces an original sound, which is shaped by a certain filter response function. It is hypothesized that human listeners evaluate sound quality by decomposing the complex spectrum of the sound according to this production model. The current research investigates the perceptual relationship among spectral attributes induced by the sound source and the filter. Specifically, the capability of listeners to extract a global spectral attribute of spectral slope determined by a sound source is examined in the context of variation with other two background attributes: fundamental frequency (another source attribute) and ripple frequency (a filter characteristic). Spectral slope is judged to be integral with these background attributes if a significant decrement in slope discrimination occurs due to a varied, relative to fixed, background attribute. The five experiments used a XAB task with roving overall spectral intensity within trials to eliminate intensity cues. The presence of a significant decrement due to roving fundamental frequency indicates that spectral slope is integral with fundamental frequency. In contrast, a strikingly smaller decrement occurs as the filter characteristic is varied, suggesting that spectral slope is more easily separable from the ripple filter attribute than from fundamental frequency. Therefore, it is conjectured that the global source attribute of spectral slope is perceptually unitized with other source attributes, and listeners treat source attributes as an entity in describing the characteristics of the sound source. However, such an evaluation of sound source attributes is relatively orthogonal to the actual spectral envelope, which may be shaped by different filter functions. The current study have extended profile analysis and demonstrated human auditory capability to resolve a global spectral

  9. 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.

  10. VESTIBULAR PERCEPTUAL THRESHOLDS INCREASE ABOVE THE AGE OF 40

    OpenAIRE

    María Carolina Bermúdez Rey; Torin K Clark; Wei Wang; Tania Leeder; Yong Bian; Dan M Merfeld

    2016-01-01

    We measured vestibular perceptual thresholds in 105 healthy humans (54F/51M) ranging from 18 to 80 years of age. Direction-recognition thresholds were measured using standard methods. The motion consisted of single cycles of sinusoidal acceleration at 0.2 Hz for roll tilt and 1.0 Hz for yaw rotation about an earth-vertical axis, inter-aural earth-horizontal translation (y-translation), inferior-superior earth-vertical translation (z-translation), and roll tilt. A large subset of this populati...

  11. Vestibular Perceptual Thresholds Increase above the Age of 40

    OpenAIRE

    Bermúdez Rey, María Carolina; Torin K Clark; Wang, Wei; Leeder, Tania; Bian, Yong; Merfeld, Daniel M.

    2016-01-01

    We measured vestibular perceptual thresholds in 105 healthy humans (54F/51M) ranging from 18 to 80 years of age. Direction-recognition thresholds were measured using standard methods. The motion consisted of single cycles of sinusoidal acceleration at 0.2 Hz for roll tilt and 1.0 Hz for yaw rotation about an earth-vertical axis, inter-aural earth-horizontal translation (y-translation), inferior–superior earth-vertical translation (z-translation), and roll tilt. A large subset of this populati...

  12. Vestibular Perceptual Thresholds Increase above the Age of 40

    OpenAIRE

    Bermúdez Rey, María Carolina; Torin K Clark; Wang, Wei; Leeder, Tania; Bian, Yong; Merfeld, Daniel M.

    2016-01-01

    We measured vestibular perceptual thresholds in 105 healthy humans (54F/51M) ranging from 18 to 80 years of age. Direction-recognition thresholds were measured using standard methods. The motion consisted of single cycles of sinusoidal acceleration at 0.2 Hz for roll tilt and 1.0 Hz for yaw rotation about an earth-vertical axis, inter-aural earth-horizontal translation (y-translation), inferior–superior earth-vertical translation (z-translation), and roll tilt. A large subset of this populati...

  13. 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.

  14. Perceptual grouping does not affect multi-attribute decision making if no processing costs are involved.

    Science.gov (United States)

    Ettlin, Florence; Bröder, Arndt

    2015-05-01

    Adaptive strategy selection implies that a decision strategy is chosen based on its fit to the task and situation. However, other aspects, such as the way information is presented, can determine information search behavior; especially when the application of certain strategies over others is facilitated. But are such display effects on multi-attribute decisions also at work when the manipulation does not entail differential costs for different decision strategies? Three Mouselab experiments with hidden information and one eye tracking experiment with an open information board revealed that decision behavior is unaffected by purely perceptual manipulations of the display based on Gestalt principles; that is, based on manipulations that induce no noteworthy processing costs for different information search patterns. We discuss our results in the context of previous findings on display effects; specifically, how the combination of these findings and our results reveal the crucial role of differential processing costs for different strategies for the emergence of display effects. This finding describes a boundary condition of the commonly acknowledged influence of information displays and is in line with the ideas of adaptive strategy selection and cost-benefit tradeoffs.

  15. 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.

  16. Emotional enhancement of perceptual priming is preserved in aging and early-stage Alzheimer's disease.

    Science.gov (United States)

    LaBar, Kevin S; Torpey, Dana C; Cook, Craig A; Johnson, Stephanie R; Warren, Lauren H; Burke, James R; Welsh-Bohmer, Kathleen A

    2005-01-01

    Perceptual priming for emotionally-negative and neutral scenes was tested in early-stage Alzheimer's disease (AD) patients and healthy younger, middle-aged and older adults. In the study phase, participants rated the scenes for their arousal properties. In the test phase, studied and novel scenes were initially presented subliminally, and the exposure duration was gradually increased until a valence categorization was made. The difference in exposure duration required to categorize novel versus studied items was the dependent measure of priming. Aversive content increased the magnitude of priming, an effect that was preserved in healthy aging and AD. Results from an immediate recognition memory test showed that the priming effects could not be attributable to enhanced explicit memory for the aversive scenes. These findings implicate a dissociation between the modulatory effect of emotion across implicit and explicit forms of memory in aging and early-stage AD.

  17. Vestibular Perceptual Thresholds Increase above the Age of 40

    Science.gov (United States)

    Bermúdez Rey, María Carolina; Clark, Torin K.; Wang, Wei; Leeder, Tania; Bian, Yong; Merfeld, Daniel M.

    2016-01-01

    We measured vestibular perceptual thresholds in 105 healthy humans (54F/51M) ranging from 18 to 80 years of age. Direction-recognition thresholds were measured using standard methods. The motion consisted of single cycles of sinusoidal acceleration at 0.2 Hz for roll tilt and 1.0 Hz for yaw rotation about an earth-vertical axis, inter-aural earth-horizontal translation (y-translation), inferior–superior earth-vertical translation (z-translation), and roll tilt. A large subset of this population (99 of 105) also performed a modified Romberg test of standing balance. Despite the relatively large population (54F/51M), we found no difference between thresholds of male and female subjects. After pooling across sex, we found that thresholds increased above the age of 40 for all five motion directions investigated. The data were best modeled by a two-segment age model that yielded a constant baseline below an age cutoff of about 40 and a threshold increase above the age cutoff. For all subjects who passed all conditions of the balance test, the baseline thresholds were 0.97°/s for yaw rotation, 0.66°/s for 1-Hz roll tilt, 0.35°/s for 0.2-Hz roll tilt, 0.58 cm/s for y-translation, and 1.24 cm/s for z-translation. As a percentage of the baseline, the fitted slopes (indicating the threshold increase each decade above the age cutoff) were 83% for z-translation, 56% for 1-Hz roll tilt, 46% for y-translation, 32% for 0.2-Hz roll tilt, and 15% for yaw rotation. Even taking age and other factors into consideration, we found a significant correlation of balance test failures with increasing roll-tilt thresholds.

  18. VESTIBULAR PERCEPTUAL THRESHOLDS INCREASE ABOVE THE AGE OF 40

    Directory of Open Access Journals (Sweden)

    María Carolina Bermúdez Rey

    2016-10-01

    Full Text Available We measured vestibular perceptual thresholds in 105 healthy humans (54F/51M ranging from 18 to 80 years of age. Direction-recognition thresholds were measured using standard methods. The motion consisted of single cycles of sinusoidal acceleration at 0.2 Hz for roll tilt and 1.0 Hz for yaw rotation about an earth-vertical axis, inter-aural earth-horizontal translation (y-translation, inferior-superior earth-vertical translation (z-translation, and roll tilt. A large subset of this population (99 of 105 also performed a modified Romberg test of standing balance. Despite the relatively large population (54F/51M, we found no difference between thresholds of male and female subjects. After pooling across sex, we found that thresholds increased above the age of 40 for all five motion-directions investigated. The data were best modeled by a two-segment age model that yielded a constant baseline below an age cut-off of about 40 and a threshold increase above the age cut-off. For all subjects who passed all conditions of the balance test, the baseline thresholds were 0.97˚/s for yaw rotation, 0.66˚/s for 1Hz roll tilt, 0.35˚/s for 0.2Hz roll tilt, 0.58cm/s for y-translation, and 1.24cm/s for z-translation. As a percentage of the baseline, the fitted slopes (indicating the threshold increase each decade above the age cut-off were 83% for z-translation, 56% for 1Hz roll tilt, 46% for y-translation, 32% for 0.2Hz roll tilt, and 15% for yaw rotation. Even taking age and other factors into consideration, we found a significant correlation of balance test failures with increasing roll tilt thresholds.

  19. Age-Related Changes in Selective Attention and Perceptual Load During Visual Search

    OpenAIRE

    Madden, David J.; Langley, Linda K.

    2003-01-01

    Three visual search experiments were conducted to test the hypothesis that age differences in selective attention vary as a function of perceptual load (E. A. Maylor & N. Lavie, 1998). Under resource-limited conditions (Experiments 1 and 2), the distraction from irrelevant display items generally decreased as display size (perceptual load) increased. This perceptual load effect was similar for younger and older adults, contrary to the findings of Maylor and Lavie. Distraction at low perceptua...

  20. 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.

  1. Age-related slowing of memory retrieval: Contributions of perceptual speed and cerebral white matter integrity

    Science.gov (United States)

    Bucur, Barbara; Madden, David J.; Spaniol, Julia; Provenzale, James M.; Cabeza, Roberto; White, Leonard E.; Huettel, Scott A.

    2007-01-01

    Previous research suggests that, in reaction time (RT) measures of episodic memory retrieval, the unique effects of adult age are relatively small compared to the effects aging shares with more elementary abilities such as perceptual speed. Little is known, however, regarding the mechanisms of perceptual speed. We used diffusion tensor imaging (DTI) to test the hypothesis that white matter integrity, as indexed by fractional anisotropy (FA), serves as one mechanism of perceptual slowing in episodic memory retrieval. Results indicated that declines in FA in the pericallosal frontal region and in the genu of the corpus callosum, but not in other regions, mediated the relationship between perceptual speed and episodic retrieval RT. This relation held, though to a different degree, for both hits and correct rejections. These findings suggest that white matter integrity in prefrontal regions is one mechanism underlying the relation between individual differences in perceptual speed and episodic retrieval. PMID:17383774

  2. Population response to natural images in the primary visual cortex encodes local stimulus attributes and perceptual processing.

    Science.gov (United States)

    Ayzenshtat, Inbal; Gilad, Ariel; Zurawel, Guy; Slovin, Hamutal

    2012-10-01

    The primary visual cortex (V1) is extensively studied with a large repertoire of stimuli, yet little is known about its encoding of natural images. Using voltage-sensitive dye imaging in behaving monkeys, we measured neural population response evoked in V1 by natural images presented during a face/scramble discrimination task. The population response showed two distinct phases of activity: an early phase that was spread over most of the imaged area, and a late phase that was spatially confined. To study the detailed relation between the stimulus and the population response, we used a simple encoding model to compute a continuous map of the expected neural response based on local attributes of the stimulus (luminance and contrast), followed by an analytical retinotopic transformation. Then, we computed the spatial correlation between the maps of the expected and observed response. We found that the early response was highly correlated with the local luminance of the stimulus and was sufficient to effectively discriminate between stimuli at the single trial level. The late response, on the other hand, showed a much lower correlation to the local luminance, was confined to central parts of the face images, and was highly correlated with the animal's perceptual report. Our study reveals a continuous spatial encoding of low- and high-level features of natural images in V1. The low level is directly linked to the stimulus basic local attributes and the high level is correlated with the perceptual outcome of the stimulus processing.

  3. The effect of normal aging and age-related macular degeneration on perceptual learning

    Science.gov (United States)

    Astle, Andrew T.; Blighe, Alan J.; Webb, Ben S.; McGraw, Paul V.

    2015-01-01

    We investigated whether perceptual learning could be used to improve peripheral word identification speed. The relationship between the magnitude of learning and age was established in normal participants to determine whether perceptual learning effects are age invariant. We then investigated whether training could lead to improvements in patients with age-related macular degeneration (AMD). Twenty-eight participants with normal vision and five participants with AMD trained on a word identification task. They were required to identify three-letter words, presented 10° from fixation. To standardize crowding across each of the letters that made up the word, words were flanked laterally by randomly chosen letters. Word identification performance was measured psychophysically using a staircase procedure. Significant improvements in peripheral word identification speed were demonstrated following training (71% ± 18%). Initial task performance was correlated with age, with older participants having poorer performance. However, older adults learned more rapidly such that, following training, they reached the same level of performance as their younger counterparts. As a function of number of trials completed, patients with AMD learned at an equivalent rate as age-matched participants with normal vision. Improvements in word identification speed were maintained at least 6 months after training. We have demonstrated that temporal aspects of word recognition can be improved in peripheral vision with training across a range of ages and these learned improvements are relatively enduring. However, training targeted at other bottlenecks to peripheral reading ability, such as visual crowding, may need to be incorporated to optimize this approach. PMID:26605694

  4. Linking cognitive and visual perceptual decline in healthy aging: The information degradation hypothesis.

    Science.gov (United States)

    Monge, Zachary A; Madden, David J

    2016-10-01

    Several hypotheses attempt to explain the relation between cognitive and perceptual decline in aging (e.g., common-cause, sensory deprivation, cognitive load on perception, information degradation). Unfortunately, the majority of past studies examining this association have used correlational analyses, not allowing for these hypotheses to be tested sufficiently. This correlational issue is especially relevant for the information degradation hypothesis, which states that degraded perceptual signal inputs, resulting from either age-related neurobiological processes (e.g., retinal degeneration) or experimental manipulations (e.g., reduced visual contrast), lead to errors in perceptual processing, which in turn may affect non-perceptual, higher-order cognitive processes. Even though the majority of studies examining the relation between age-related cognitive and perceptual decline have been correlational, we reviewed several studies demonstrating that visual manipulations affect both younger and older adults' cognitive performance, supporting the information degradation hypothesis and contradicting implications of other hypotheses (e.g., common-cause, sensory deprivation, cognitive load on perception). The reviewed evidence indicates the necessity to further examine the information degradation hypothesis in order to identify mechanisms underlying age-related cognitive decline.

  5. Attributional, Perceptual, and Affective Responses to Depressed and Nondepressed Marital Partners.

    Science.gov (United States)

    Sacco, William P.; And Others

    1993-01-01

    Husbands of wives with (n=22) or without (n=23) history of depressive disorder indicated their attributions about and affective reactions to real and hypothetical positive and negative events occurring to their wives, rated their wives on personality traits, and reported their own marital satisfaction. Depressed wives were rated more negatively on…

  6. 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…

  7. 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

    2015-01-01

    Although 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 morphologic analyses, we investigated whether aging affects areal size of the early visual cortex, which were retinotopically localized, and whether those morphologic 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.

  8. 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

  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. 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.

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

    NARCIS (Netherlands)

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

    2014-01-01

    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 participan

  12. The Effects of Age on Perceptual Problem-Solving Strategies.

    Science.gov (United States)

    Lee, Jo Ann; Pollack, Robert H.

    Witkin's Embedded Figures Test (EFT) was used to measure the changes with age in field dependence and problem-solving ability. Qualitative data concerning problem-solving strategies and quantitative data were collected. EFT was administered to 12 females in each of the following decades: 20s, 30s, 40s, 50s, 60s, 70s. All subjects were moderately…

  13. 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

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

    Directory of Open Access Journals (Sweden)

    Anna eRemington

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Decoding simulated neurodynamics predicts the perceptual consequences of age-related macular degeneration.

    Science.gov (United States)

    Shi, Jianing V; Wielaard, Jim; Smith, R Theodore; Sajda, Paul

    2011-12-05

    Age-related macular degeneration (AMD) is the major cause of blindness in the developed world. Though substantial work has been done to characterize the disease, it is difficult to predict how the state of an individual's retina will ultimately affect their high-level perceptual function. In this paper, we describe an approach that couples retinal imaging with computational neural modeling of early visual processing to generate quantitative predictions of an individual's visual perception. Using a patient population with mild to moderate AMD, we show that we are able to accurately predict subject-specific psychometric performance by decoding simulated neurodynamics that are a function of scotomas derived from an individual's fundus image. On the population level, we find that our approach maps the disease on the retina to a representation that is a substantially better predictor of high-level perceptual performance than traditional clinical metrics such as drusen density and coverage. In summary, our work identifies possible new metrics for evaluating the efficacy of treatments for AMD at the level of the expected changes in high-level visual perception and, in general, typifies how computational neural models can be used as a framework to characterize the perceptual consequences of early visual pathologies.

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

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; 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 capacity and the visua...... speed of Visual Short-term Memory (VTSM) but not the capacity of VSTM nor the visual 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.......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 capacity and the visual...... perceptual encoding/decoding speed (processing speed) of visual short-term memory based on an assessment of 91 healthy subjects aged 60-75. The estimates are presented at total sample level as well as at gender level. The estimates were modelled from input from a whole-report assessment based on A Theory...

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

    Science.gov (United States)

    Remington, Anna; Cartwright-Finch, Ula; Lavie, Nilli

    2014-01-01

    Attention and awareness are known to be linked (e.g., see Lavie et al., 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 hypothesized 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 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.

  20. Effect of visual cues on the resolution of perceptual ambiguity in Parkinson's disease and normal aging.

    Science.gov (United States)

    Díaz-Santos, Mirella; Cao, Bo; Mauro, Samantha A; Yazdanbakhsh, Arash; Neargarder, Sandy; Cronin-Golomb, Alice

    2015-02-01

    Parkinson's disease (PD) and normal aging have been associated with changes in visual perception, including reliance on external cues to guide behavior. This raises the question of the extent to which these groups use visual cues when disambiguating information. Twenty-seven individuals with PD, 23 normal control adults (NC), and 20 younger adults (YA) were presented a Necker cube in which one face was highlighted by thickening the lines defining the face. The hypothesis was that the visual cues would help PD and NC to exert better control over bistable perception. There were three conditions, including passive viewing and two volitional-control conditions (hold one percept in front; and switch: speed up the alternation between the two). In the Hold condition, the cue was either consistent or inconsistent with task instructions. Mean dominance durations (time spent on each percept) under passive viewing were comparable in PD and NC, and shorter in YA. PD and YA increased dominance durations in the Hold cue-consistent condition relative to NC, meaning that appropriate cues helped PD but not NC hold one perceptual interpretation. By contrast, in the Switch condition, NC and YA decreased dominance durations relative to PD, meaning that the use of cues helped NC but not PD in expediting the switch between percepts. Provision of low-level cues has effects on volitional control in PD that are different from in normal aging, and only under task-specific conditions does the use of such cues facilitate the resolution of perceptual ambiguity.

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

    Science.gov (United States)

    Wiegand, Iris; Finke, Kathrin; Müller, Hermann J; Töllner, Thomas

    2013-03-01

    Attentional decline plays a major role in cognitive changes with aging. However, which specific aspects of attention contribute to this decline is as yet little understood. To identify the contributions of various potential sources of age decrements in visual search, we combined response time 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 to the next revealed repetition facilitation of the target-defining dimension and of the motor response-originating from preattentive perceptual and motor execution stages, respectively-to be independent of age. Critically, we demonstrated specific age deficits on intermediate processing stages when intertrial changes required more executively controlled processes, such as flexible stimulus-response (re-)mapping across trials.

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

    Directory of Open Access Journals (Sweden)

    Jeffrey eBower

    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.

  3. Motor and Tactile-Perceptual Skill Differences between Individuals with High-Functioning Autism and Typically Developing Individuals Ages 5-21

    Science.gov (United States)

    Abu-Dahab, Sana M. N.; Skidmore, Elizabeth R.; Holm, Margo B.; Rogers, Joan C.; Minshew, Nancy J.

    2013-01-01

    We examined motor and tactile-perceptual skills in individuals with high-functioning autism (IHFA) and matched typically developing individuals (TDI) ages 5-21 years. Grip strength, motor speed and coordination were impaired in IHFA compared to matched TDI, and the differences between groups varied with age. Although tactile-perceptual skills of…

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

    Science.gov (United States)

    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…

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

    Directory of Open Access Journals (Sweden)

    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

  6. Auditory Perceptual Learning in Adults with and without Age-Related Hearing Loss

    Science.gov (United States)

    Karawani, Hanin; Bitan, Tali; Attias, Joseph; Banai, Karen

    2016-01-01

    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 : Fifty-six 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

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

    Directory of Open Access Journals (Sweden)

    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

  8. Age-related increases in false recognition: The role of perceptual and conceptual similarity

    Directory of Open Access Journals (Sweden)

    Laura M. Pidgeon

    2014-10-01

    Full Text Available Older adults are more likely to falsely recognize novel events than young adults, and recent behavioral and neuroimaging evidence points to a reduced ability to distinguish overlapping information due to decline in hippocampal pattern separation. However, other data suggest a critical role for semantic similarity. Koutstaal et al. [(2003. False recognition of abstract versus common objects in older and younger adults: Testing the semantic categorization account, J. Exp Psychol. Learn, 29(4, 499-510] reported that older adults were only vulnerable to false recognition of items with pre-existing semantic representations. We replicated Koutstaal et al.’s (2003 second experiment and examined the influence of independently rated perceptual and conceptual similarity between stimuli and lures. At study, young and older adults judged the pleasantness of pictures of abstract (unfamiliar and concrete (familiar items, followed by a surprise recognition test including studied items, similar lures, and novel unrelated items. Experiment 1 used dichotomous ‘old/new’ responses at test, while in Experiment 2 participants were also asked to judge lures as ‘similar’, to increase explicit demands on pattern separation. In both experiments, older adults showed a greater increase in false recognition for concrete than abstract items relative to the young, replicating Koutstaal et al.’s (2003 findings. However, unlike in the earlier study, there was also an age-related increase in false recognition of abstract lures when multiple similar images had been studied. In line with pattern separation accounts of false recognition, older adults were more likely to misclassify concrete lures with high and moderate, but not low degrees of rated similarity to studied items. Results are consistent with the view that older adults are particularly susceptible to semantic interference in recognition memory, and with the possibility that this reflects age-related decline

  9. Perception and Cognition in the Ageing Brain: A Brief Review of the Short- and Long-Term Links between Perceptual and Cognitive Decline.

    Science.gov (United States)

    Roberts, Katherine L; Allen, Harriet A

    2016-01-01

    Ageing is associated with declines in both perception and cognition. We review evidence for an interaction between perceptual and cognitive decline in old age. Impoverished perceptual input can increase the cognitive difficulty of tasks, while changes to cognitive strategies can compensate, to some extent, for impaired perception. While there is strong evidence from cross-sectional studies for a link between sensory acuity and cognitive performance in old age, there is not yet compelling evidence from longitudinal studies to suggest that poor perception causes cognitive decline, nor to demonstrate that correcting sensory impairment can improve cognition in the longer term. Most studies have focused on relatively simple measures of sensory (visual and auditory) acuity, but more complex measures of suprathreshold perceptual processes, such as temporal processing, can show a stronger link with cognition. The reviewed evidence underlines the importance of fully accounting for perceptual deficits when investigating cognitive decline in old age.

  10. Attribution of Responsibility by Japanese and Americans as a Function of Age

    Science.gov (United States)

    Shaw, Marvin E.; Iwawaki, Saburo

    1972-01-01

    Two age groups of Japanese and Americans were experimentally compared in the attribution of responsibility. The findings of the study were interpreted in terms of cultural differences in values and parental reward patterns, and show great cultural similarities in the attribution of responsibility. (Authors)

  11. Changes in perceptual speed and white matter microstructure in the corticospinal tract are associated in very old age.

    Science.gov (United States)

    Lövdén, Martin; Köhncke, Ylva; Laukka, Erika J; Kalpouzos, Grégoria; Salami, Alireza; Li, Tie-Qiang; Fratiglioni, Laura; Bäckman, Lars

    2014-11-15

    The integrity of the brain's white matter is important for neural processing and displays age-related differences, but the contribution of changes in white matter to cognitive aging is unclear. We used latent change modeling to investigate this issue in a sample of very old adults (aged 81-103 years) assessed twice with a retest interval of 2.3 years. Using diffusion-tensor imaging, we probed white matter microstructure by quantifying mean fractional anisotropy and mean diffusivity of six major white matter tracts. Measures of perceptual speed, episodic memory, letter fluency, category fluency, and semantic memory were collected. Across time, alterations of white matter microstructure in the corticospinal tract were associated with decreases of perceptual speed. This association remained significant after statistically controlling for changes in white matter microstructure in the entire brain, in the other demarcated tracts, and in the other cognitive abilities. Changes in brain volume also did not account for the association. We conclude that white matter microstructure is a potent correlate of changes in sensorimotor aspects of behavior in very old age, but that it is unclear whether its impact extends to higher-order cognition.

  12. The effects of perceptual motor development programs on balance and quickness at preschool children aged between 4 and 6

    Directory of Open Access Journals (Sweden)

    Ertan Tüfekçioğlu

    2008-09-01

    Full Text Available Preschool is the term that allows the most positive and permanent contributions to movements skills to be realized. This term includes the development stages that may shape whole life. It is known that, apporpriate education programs in sensitive age terms accelerate development at children. Therefore, the effects of perceptual motor development programs on balance and qucikness will be examined in this study.Pre-test Post-test control group model is carried out  in this study. 62 children, consisting of 30 for test group and 32 for control gorup and ages of which changing between 4 and 6 were participated in this study. Perceptual motor development activities were applied on test group for a period of 14 weeks and pre-test and post-test differences were analized by independent samples t test between the groups. Consequently; while significant differences (p<0.01 were seen at within-group measurements, there was no significant difference at between-group measurements (p>0.05 at the pre-test post test values of motor performance of test group and control gorup.

  13. The effects of perceptual motor development programs on balance and quickness at preschool children aged between 4 and 6

    Directory of Open Access Journals (Sweden)

    Ertan Tüfekçioğlu

    2008-09-01

    Full Text Available Preschool is the term that allows the most positive and permanent contributions to movements skills to be realized. This term includes the development stages that may shape whole life. It is known that, apporpriate education programs in sensitive age terms accelerate development at children. Therefore, the effects of perceptual motor development programs on balance and qucikness will be examined in this study.Pre-test Post-test control group model is carried out in this study. 62 children, consisting of 30 for test group and 32 for control gorup and ages of which changing between 4 and 6 were participated in this study. Perceptual motor development activities were applied on test group for a period of 14 weeks and pre-test and post-test differences were analized by independent samples t test between the groups. Consequently; while significant differences (p0.05 at the pre-test post test values of motor performance of test group and control gorup.

  14. Neonatal pain-related stress, functional cortical activity and visual-perceptual abilities in school-age children born at extremely low gestational age.

    Science.gov (United States)

    Doesburg, Sam M; Chau, Cecil M; Cheung, Teresa P L; Moiseev, Alexander; Ribary, Urs; Herdman, Anthony T; Miller, Steven P; Cepeda, Ivan L; Synnes, Anne; Grunau, Ruth E

    2013-10-01

    Children born very prematurely (neonatal experience and neurodevelopment, remain poorly understood. Repeated procedural pain-related stress during neonatal intensive care has been proposed to contribute to altered neurocognitive development in these children. Due to critical periods in the development of thalamocortical systems, the immature brain of infants born at extremely low gestational age (ELGA; neonatal pain. In a cohort of school-age children followed since birth we assessed relations between functional brain activity measured using magnetoencephalogragy (MEG), visual-perceptual abilities and cumulative neonatal pain. We demonstrated alterations in the spectral structure of spontaneous cortical oscillatory activity in ELGA children at school-age. Cumulative neonatal pain-related stress was associated with changes in background cortical rhythmicity in these children, and these alterations in spontaneous brain oscillations were negatively correlated with visual-perceptual abilities at school-age, and were not driven by potentially confounding neonatal variables. These findings provide the first evidence linking neonatal pain-related stress, the development of functional brain activity, and school-age cognitive outcome in these vulnerable children.

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

    Directory of Open Access Journals (Sweden)

    Inge Linda Wilms

    2014-10-01

    Full Text Available 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 capacity and the visual perceptual encoding/decoding speed (processing speed of Visual Short-Term Memory (VSTM based on an assessment of 91 healthy subjects aged 60-75. The estimates were modelled from input from a whole-report assessment based on A Theory of Visual Attention (TVA. 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.

  16. 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.

  17. Effects of dry-aging on meat quality attributes and metabolite profiles of beef loins.

    Science.gov (United States)

    Kim, Yuan H Brad; Kemp, Robert; Samuelsson, Linda M

    2016-01-01

    The objectives of this study were to evaluate different dry-aging regimes and their impacts on quality attributes and metabolite profiles of beef loins. Thirty loins (M. longissimus lumborum) from 15 beef carcasses at 2 days post-mortem were obtained. Each loin was cut in half yielding 60 sections, which were randomly assigned to six treatments including 4 dry-aging (2 temperatures (1 or 3°C) × 2 air-velocities (0.2 or 0.5 m/s)) and 2 wet-aging regimes for 3 weeks; n=10/treatment. The sensory panel found that dry-aged loins had better flavour and overall liking (Pdry-aged beef compared to the wet-aged beef, which may contribute to the enhanced flavours of the dry-aged beef. Overall, dry-aging loins at 3°C with 0.2m/s resulted in the greatest improvement in beef palatability.

  18. Attributing heart attack and stroke to "Old Age": Implications for subsequent health outcomes among older adults.

    Science.gov (United States)

    Stewart, Tara L; Chipperfield, Judith G; Perry, Raymond P; Hamm, Jeremy M

    2016-01-01

    This study assessed the extent to which older adults attribute a recent heart attack/stroke to "old age," and examined consequences for subsequent lifestyle behavior and health-care service utilization. Community-dwelling adults (N = 57, ages 73-98 years) were interviewed about their heart attack/stroke, and an objective health registry provided data on health-care utilization over a 3-year period. Endorsement of "old age" as a cause of heart attack/stroke negatively predicted lifestyle behavior change, and positively predicted frequency of physician visits and likelihood of hospitalization over the subsequent 3 years. Findings suggest the importance of considering "old age" attributions in the context of cardiovascular health events.

  19. Effect of age on reproductive attributes of an aphidophagous ladybird, Cheilomenes sexmaculata

    Institute of Scientific and Technical Information of China (English)

    OMKAR, SATYENDRA K. SINGH; KALPANA SINGH

    2006-01-01

    The effect of both male and female age was investigated on certain reproductive attributes, viz. mating incidence, mating duration, fecundity, percent egg viability, ratio of reproductive and non-reproductive periods and reproductive rate, of an aphidophagous ladybird, Cheilomenes sexmaculata (Fabricius). Females started mating at the age of 8 hours post-emergence (PE) and males at the age of 2 days PE. Mating in the laboratory was a maledominated phenomenon. The mating duration and reproductive rate of 10-day-old females when mated with males of varying ages increased up to the male age of 60 days, and thereafter decreased, whereas, fecundity, egg viability and ratio of reproductive and non-reproductive periods increased up to the male age of 50 days, and thereafter declined. However, when females of varying ages were mated with 10-day-old males, fecundity and reproductive rate increased up to 40 days of female age, respectively, then decreased. The ratio of reproductive and non-reproductive periods increased with increasing age of females. Mating age for optimal reproductive output was 10-50-day-old males and NE to 40-day-old females.Reproductive cessation in males was recorded after 50 days PE, whereas in females at the age of 40 days PE. Higher mating durations lead to elevated reproductive rates. Delay in the reproductive phase was positively correlated with longevity. The results of this study may aid mass multiplication of this ladybird by identifying and promoting usage of adults of optimal age. Our results also enhance our understanding of the effect of age on reproductive attributes in ladybirds.

  20. Perceptual Constraints in Phonotactic Learning

    Science.gov (United States)

    Endress, Ansgar D.; Mehler, Jacques

    2010-01-01

    Structural regularities in language have often been attributed to symbolic or statistical general purpose computations, whereas perceptual factors influencing such generalizations have received less interest. Here, we use phonotactic-like constraints as a case study to ask whether the structural properties of specific perceptual and memory…

  1. 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.

  2. Perceptual-binding and persistent surface segregation.

    Science.gov (United States)

    Moradi, Farshad; Shimojo, Shinsuke

    2004-11-01

    Visual input is segregated in the brain into subsystems that process different attributes such as motion and color. At the same time, visual information is perceptually segregated into objects and surfaces. Here we demonstrate that perceptual segregation of visual entities based on a transparency cue precedes and affects perceptual binding of attributes. Adding an irrelevant transparency cue paradoxically improved the pairing of color and motion for rapidly alternating surfaces. Subsequent experiments show: (1) Attributes are registered over the temporal window defined by the perceptual persistence of segregation, resulting in asynchrony in binding, and (2) attention is necessary for correct registration of attributes in the presence of ambiguity.

  3. 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

    Attentional decline plays a major role in cognitive changes with aging. However, which specific aspects of attention contribute to this decline is as yet little understood. To identify the contributions of various potential sources of age decrements in visual search, we combined response time...... 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...

  4. Preservation of perceptual integration improves temporal stability of bimanual coordination in the elderly: an evidence of age-related brain plasticity.

    Science.gov (United States)

    Blais, Mélody; Martin, Elodie; Albaret, Jean-Michel; Tallet, Jessica

    2014-12-15

    Despite the apparent age-related decline in perceptual-motor performance, recent studies suggest that the elderly people can improve their reaction time when relevant sensory information are available. However, little is known about which sensory information may improve motor behaviour itself. Using a synchronization task, the present study investigates how visual and/or auditory stimulations could increase accuracy and stability of three bimanual coordination modes produced by elderly and young adults. Neurophysiological activations are recorded with ElectroEncephaloGraphy (EEG) to explore neural mechanisms underlying behavioural effects. Results reveal that the elderly stabilize all coordination modes when auditory or audio-visual stimulations are available, compared to visual stimulation alone. This suggests that auditory stimulations are sufficient to improve temporal stability of rhythmic coordination, even more in the elderly. This behavioural effect is primarily associated with increased attentional and sensorimotor-related neural activations in the elderly but similar perceptual-related activations in elderly and young adults. This suggests that, despite a degradation of attentional and sensorimotor neural processes, perceptual integration of auditory stimulations is preserved in the elderly. These results suggest that perceptual-related brain plasticity is, at least partially, conserved in normal aging.

  5. Age-related changes in consolidation of perceptual and muscle-based learning of motor skills

    OpenAIRE

    Rebecca M. C. Spencer; Pace-Schott, Edward F.

    2013-01-01

    Improvements in motor sequence learning come about via goal-based learning of the sequence of visual stimuli and muscle-based learning of the sequence of movement responses. In young adults, consolidation of goal-based learning is observed after intervals of sleep but not following wake, whereas consolidation of muscle-based learning is greater following intervals with wake compared to sleep. While the benefit of sleep on motor sequence learning has been shown to decline with age, how sleep c...

  6. Perceptual-binding and persistent surface segregation

    OpenAIRE

    2004-01-01

    Visual input is segregated in the brain into subsystems that process different attributes such as motion and color. At the same time, visual information is perceptually segregated into objects and surfaces. Here we demonstrate that perceptual segregation of visual entities based on a transparency cue precedes and affects perceptual binding of attributes. Adding an irrelevant transparency cue paradoxically improved the pairing of color and motion for rapidly alternating surfaces. Subsequent ex...

  7. Age-related changes in consolidation of perceptual and muscle-based learning of motor skills

    Directory of Open Access Journals (Sweden)

    Rebecca M. C. Spencer

    2013-11-01

    Full Text Available Improvements in motor sequence learning come about via goal-based learning of the sequence of visual stimuli and muscle-based learning of the sequence of movement responses. In young adults, consolidation of goal-based learning is observed after intervals of sleep but not following wake, whereas consolidation of muscle-based learning is greater following intervals with wake compared to sleep. While the benefit of sleep on motor sequence learning has been shown to decline with age, how sleep contributes to consolidation of goal-based versus muscle-based learning in older adults has not been disentangled. We trained young (n=62 and older (n=50 adults on a motor sequence learning task and re-tested learning following 12 hr intervals containing overnight sleep or daytime wake. To probe consolidation of goal-based learning of the sequence, half of the participants were re-tested in a configuration in which the stimulus sequence was the same but, due to a shift in stimulus-response mapping, the movement response sequence differed. To probe consolidation of muscle-based learning, the remaining participants were tested in a configuration in which the stimulus sequence was novel, but now the sequence of movements used for responding was unchanged. In young adults, there was a significant condition (goal-based v. muscle-based learning by interval (sleep v. wake interaction, F(1,58=6.58, p=.013: Goal-based learning tended to be greater following sleep compared to wake, t(29=1.47, p=.072. Conversely, muscle-based learning was greater following wake than sleep, t(29=2.11, p=.021. Unlike young adults, this interaction was not significant in older adults, F(1,46=.04, p=.84, nor was there a main effect of interval, F(1,46=1.14, p=.29. Thus, older adults do not preferentially consolidate sequence learning over wake or sleep.

  8. Age-related changes in consolidation of perceptual and muscle-based learning of motor skills.

    Science.gov (United States)

    Pace-Schott, Edward F; Spencer, Rebecca M C

    2013-01-01

    Improvements in motor sequence learning come about via goal-based learning of the sequence of visual stimuli and muscle-based learning of the sequence of movement responses. In young adults, consolidation of goal-based learning is observed after intervals of sleep but not following wake, whereas consolidation of muscle-based learning is greater following intervals with wake compared to sleep. While the benefit of sleep on motor sequence learning has been shown to decline with age, how sleep contributes to consolidation of goal-based vs. muscle-based learning in older adults (OA) has not been disentangled. We trained young (n = 62) and older (n = 50) adults on a motor sequence learning task and re-tested learning following 12 h intervals containing overnight sleep or daytime wake. To probe consolidation of goal-based learning of the sequence, half of the participants were re-tested in a configuration in which the stimulus sequence was the same but, due to a shift in stimulus-response mapping, the movement response sequence differed. To probe consolidation of muscle-based learning, the remaining participants were tested in a configuration in which the stimulus sequence was novel, but now the sequence of movements used for responding was unchanged. In young adults, there was a significant condition (goal-based vs. muscle-based learning) by interval (sleep vs. wake) interaction, F(1,58) = 6.58, p = 0.013: goal-based learning tended to be greater following sleep compared to wake, t(29) = 1.47, p = 0.072. Conversely, muscle-based learning was greater following wake than sleep, t(29) = 2.11, p = 0.021. Unlike young adults, this interaction was not significant in OA, F(1,46) = 0.04, p = 0.84, nor was there a main effect of interval, F(1,46) = 1.14, p = 0.29. Thus, OA do not preferentially consolidate sequence learning over wake or sleep.

  9. Environmental manipulations alter age differences in attribution of incentive salience to reward-paired cues.

    Science.gov (United States)

    Anderson, Rachel I; Bush, Peter C; Spear, Linda P

    2013-11-15

    Cues repeatedly paired with rewards often themselves become imbued with enhanced motivational value, or incentive salience. During Pavlovian conditioned approach procedures, a cue repeatedly preceding reward delivery often elicits conditioned responses at either the reward delivery location ("goal-tracking") or the cue itself ("sign-tracking"). Sign-tracking behavior is thought to reflect the individual differences in attribution of incentive salience to reward-paired cues that may contribute to addiction vulnerability. Adolescent rats typically demonstrate less sign-tracking behavior than adult rats, a surprising finding given that adolescence is hypothesized to be a time of heightened addiction vulnerability. Given evidence that adult sign-tracking behavior can be influenced by environmental conditions, the present study compared the effects of isolate housing and food deprivation on expression of sign-tacking and goal-tracking behavior in adolescent and adult male rats across eight days of a Pavlovian conditioned approach procedure. Pair-housed adults exhibited more sign-tracking behavior than pair-housed adolescents; however, this age difference was not apparent in isolate-housed subjects. Adolescents often appeared more sensitive than adults to both food restriction- and isolate housing-induced changes in behavior, with food restriction promoting an increase in sign-tracking among isolate-housed adolescents and an increase in goal-tracking among pair-housed adolescents. For adults, food restriction resulted in a modest increase in overall expression of both sign- and goal-tracking behavior. To the extent that sign-tracking behavior reflects attribution of incentive salience to reward-paired cues, results from the present study provide evidence that reactivity to rewards during adolescence is strongly related to the nature of the surrounding environment.

  10. Gains following perceptual learning are closely linked to the initial visual acuity.

    Science.gov (United States)

    Yehezkel, Oren; Sterkin, Anna; Lev, Maria; Levi, Dennis M; Polat, Uri

    2016-04-28

    The goal of the present study was to evaluate the dependence of perceptual learning gains on initial visual acuity (VA), in a large sample of subjects with a wide range of VAs. A large sample of normally sighted and presbyopic subjects (N = 119; aged 40 to 63) with a wide range of uncorrected near visual acuities (VA, -0.12 to 0.8 LogMAR), underwent perceptual learning. Training consisted of detecting briefly presented Gabor stimuli under spatial and temporal masking conditions. Consistent with previous findings, perceptual learning induced a significant improvement in near VA and reading speed under conditions of limited exposure duration. Our results show that the improvements in VA and reading speed observed following perceptual learning are closely linked to the initial VA, with only a minor fraction of the observed improvement that may be attributed to the additional sessions performed by those with the worse VA.

  11. The left perceptual bias for adult and infant faces in adults and 5-year-old children: face age matters.

    Science.gov (United States)

    Proietti, Valentina; Pavone, Sarah; Ricciardelli, Paola; Macchi Cassia, Viola

    2015-01-01

    A large number of studies have shown that adults rely more heavily on information conveyed by the left side of the face in judging emotional state, gender and identity. This phenomenon, called left perceptual bias (LPB), suggests a right hemisphere lateralization of face processing mechanisms. Although specialization of neural mechanisms for processing over-experienced face categories begins during the first year of life, little is known about the developmental trajectory of the LPB and whether or when the bias becomes selective for specific face categories as a result of experience. To address these questions we tested adults (Experiment 1) and 5-year-old children (Experiment 2) with null or limited experience with infants in an identity matching-to-sample task with chimeric adult and infant faces, for which both adults and children have been shown to manifest differential processing abilities. Results showed that 5-year-olds manifest a leftward bias selective for adult faces, and the magnitude of the bias is larger for adult compared to infant faces in adults. This evidence is in line with earlier demonstrations of a perceptual processing advantage for adult faces in adults and children and points to the role of experience in shaping neurocognitive specialization for face processing.

  12. A study of the age attribute in a query tool for a clinical data warehouse.

    Science.gov (United States)

    Scheufele, Elisabeth L; Scheufele, Elisabeth Lee; Dubey, Anil; Dubey, Anil Kumar; Murphy, Shawn N

    2008-11-06

    The RPDR, a clinical data warehouse with a user-friendly Querytool, allows researchers to perform studies on patient data. Currently, the RPDR represents age as the patient's age at the present time, which is problematic in situations where age at the time of the event is more appropriate. We will modify the Querytool to consider this by assessing the perception of age via survey, testing backend query solutions, and developing modifications based on these results.

  13. Effect of different aging temperatures prior to freezing on meat quality attributes of frozen/thawed lamb loins.

    Science.gov (United States)

    Choe, Ju-Hui; Stuart, Adam; Kim, Yuan H Brad

    2016-06-01

    The objective of this study was to determine the effect of different aging temperatures prior to freezing on quality attributes of frozen/thawed lamb loins. The loins (M. longissimus lumborum; n=32) were randomly allocated to one of the four different aging/freezing treatments: aged only (-1.5°C for 14 days) and aged (-1.5°C for 14 days, 3°C for 8 days, or 7°C for 8days) then frozen/thawed loins. The loins aged at elevated temperatures (3°C or 7°C) for 8 days had equivalent shear force, protein degradation and purge loss values compared to the loins aged at -1.5°C for 14 days (P>0.05). However, significantly higher drip loss and less color stability were observed in the loins with increasing aging temperatures compared to the loins aged at -1.5°C. These results suggest that application of elevated aging temperatures could shorten required aging periods prior to freezing, while not adversely affecting tenderness and purge loss of frozen/thawed meat.

  14. Building a Method for Researching Attribution of Meaning by Children Aged 5 to 6 in School

    Science.gov (United States)

    Tertoolen, Anja; van Oers, Bert; Geldens, Jeannette; Popeijus, Herman

    2012-01-01

    This article reports on the first phase of a research project in which we looked for the voices of young children, aged 5 to 6, in school. What do children experience in school? What do they see as the meaning of school? What is their motivation? Children have the right to be listened to. The question is which settings, under which circumstances,…

  15. Continuity and Discontinuity of Perceptual Development.

    Science.gov (United States)

    Fischer, Hardi

    Despite external changes such as those of magnitudes, the functional properties of the visual system also improve with increased age. According to Jean Piaget's centration/decentration theory, the process of perceptual development might continue until adulthood and even after. However, perceptual development should not be understood in all of its…

  16. Motion transparency promotes synchronous perceptual binding.

    Science.gov (United States)

    Clifford, Colin W G; Spehar, Branka; Pearson, Joel

    2004-12-01

    While identified regions of human extrastriate visual cortex are functionally specialized for processing different attributes of an object, the cognitive and neural mechanisms by which these attributes are dynamically bound into integrated percepts are still largely mysterious. Here, we report that perceptual organization influences the dynamics of binding. Specifically, the perception of motion transparency promotes the synchronous perceptual binding of colour and motion, which otherwise exhibits considerable asynchronies. In addition, we demonstrate that perceptual asynchrony can be reinstated by manipulating stereoscopic disparity or speed within the stimulus. Our findings suggest that the phenomenology of colour-motion binding parallels the known physiology of motion processing in area MT of primate visual cortex, supporting the view that the dynamics of perceptual binding is a direct reflection of the time course of the underlying neural processing.

  17. Perceptual Repetition Blindness Effects

    Science.gov (United States)

    Hochhaus, Larry; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    The phenomenon of repetition blindness (RB) may reveal a new limitation on human perceptual processing. Recently, however, researchers have attributed RB to post-perceptual processes such as memory retrieval and/or reporting biases. The standard rapid serial visual presentation (RSVP) paradigm used in most RB studies is, indeed, open to such objections. Here we investigate RB using a "single-frame" paradigm introduced by Johnston and Hale (1984) in which memory demands are minimal. Subjects made only a single judgement about whether one masked target word was the same or different than a post-target probe. Confidence ratings permitted use of signal detection methods to assess sensitivity and bias effects. In the critical condition for RB a precue of the post-target word was provided prior to the target stimulus (identity precue), so that the required judgement amounted to whether the target did or did not repeat the precue word. In control treatments, the precue was either an unrelated word or a dummy.

  18. 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

  19. Dry versus wet aging of beef: Retail cutting yields and consumer sensory attribute evaluations of steaks from ribeyes, strip loins, and top sirloins from two quality grade groups.

    Science.gov (United States)

    Laster, M A; Smith, R D; Nicholson, K L; Nicholson, J D W; Miller, R K; Griffin, D B; Harris, K B; Savell, J W

    2008-11-01

    Top Choice (n=48) and Select (n=48) paired bone-in ribeye rolls, bone-in strip loins, and boneless top sirloin butts were assigned randomly to one of two aging treatments, dry or wet, and were aged for 14, 21, 28 or 35d. Cutting tests, performed to determine retail yields and processing times, showed dry-aged subprimals had lower total saleable yield percentages and increased processing times compared to wet-aged subprimals. Sensory and Warner-Bratzler shear evaluation was conducted to determine palatability characteristics. For the most part, aging treatment and aging period did not affect consumer sensory attributes. However, ribeye and top loin steaks from the Top Choice quality grade group received higher sensory ratings than their Select counterparts. For top sirloin steaks, no consumer sensory attributes were affected by aging treatment, aging period, or quality grade group.

  20. 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

  1. Epidemiological pathology of dementia: attributable-risks at death in the Medical Research Council Cognitive Function and Ageing Study.

    Directory of Open Access Journals (Sweden)

    Fiona E Matthews

    2009-11-01

    Full Text Available BACKGROUND: Dementia drug development aims to modulate pathological processes that cause clinical syndromes. Population data (epidemiological neuropathology will help to model and predict the potential impact of such therapies on dementia burden in older people. Presently this can only be explored through post mortem findings. We report the attributable risks (ARs for dementia at death for common age-related degenerative and vascular pathologies, and other factors, in the MRC Cognitive Function and Ageing Study (MRC CFAS. METHODS AND FINDINGS: A multicentre, prospective, longitudinal study of older people in the UK was linked to a brain donation programme. Neuropathology of 456 consecutive brain donations assessed degenerative and vascular pathologies. Logistic regression modelling, with bootstrapping and sensitivity analyses, was used to estimate AR at death for dementia for specific pathologies and other factors. The main contributors to AR at death for dementia in MRC CFAS were age (18%, small brain (12%, neocortical neuritic plaques (8% and neurofibrillary tangles (11%, small vessel disease (12%, multiple vascular pathologies (9%, and hippocampal atrophy (10%. Other significant factors include cerebral amyloid angiopathy (7% and Lewy bodies (3%. CONCLUSIONS: Such AR estimates cannot be derived from the living population; rather they estimate the relative contribution of specific pathologies to dementia at death. We found that multiple pathologies determine the overall burden of dementia. The impact of therapy targeted to a specific pathology may be profound when the dementia is relatively "pure," but may be less impressive for the majority with mixed disease, and in terms of the population. These data justify a range of strategies, and combination therapies, to combat the degenerative and vascular determinants of cognitive decline and dementia. Please see later in the article for the Editors' Summary.

  2. Children's Internal Attributions of Anxiety-Related Physical Symptoms: Age-Related Patterns and the Role of Cognitive Development and Anxiety Sensitivity

    Science.gov (United States)

    Muris, Peter; Mayer, Birgit; Freher, Nancy Kramer; Duncan, Sylvana; van den Hout, Annemiek

    2010-01-01

    The present study examined age-related patterns in children's anxiety-related interpretations and internal attributions of physical symptoms. A large sample of 388 children aged between 4 and 13 years completed a vignette paradigm during which they had to explain the emotional response of the main character who experienced anxiety-related physical…

  3. Children's internal attributions of anxiety-related physical symptoms: Age-related patterns and the role of cognitive development and anxiety sensitivity

    NARCIS (Netherlands)

    P.E.H.M. Muris (Peter); B.N. Mayer (Birgit); N.K. Freher (Nancy Kramer); S. Duncan (Sylvana); M.F.C.M. Van Den Hout (Mari F. C. M.)

    2010-01-01

    textabstractThe present study examined age-related patterns in children's anxiety-related interpretations and internal attributions of physical symptoms. A large sample of 388 children aged between 4 and 13 years completed a vignette paradigm during which they had to explain the emotional response o

  4. Comparing the Effects of Drug Therapy, Perceptual Motor Training, and Both Combined on the Motor Skills of School-Aged Attention Deficit Hyperactivity Disorder Children.

    Science.gov (United States)

    Taft Yazd, Susan Nasiri; Ayatizadeh, Farahnaz; Dehghan, Faezeh; Machado, Sergio; Wegner, Mirko

    2015-01-01

    The purpose of this research was to compare the effects of drug therapy, perceptual motor training and a combination of drug therapy and perceptual motor training on gross and fine motor skills of 6 to 12 year-old Iranian attention deficit hyperactivity disorder children. Thirty-six attention deficit hyperactivity disorder children currently under treatment in three Iranian psychological-neurological clinics participated in this research study. Participants were sampled from the accessible population and randomly assigned to three experimental groups (n = 12 each). The Conners Parent Rating Scale was used to classify the children and the Bruininks-Oseretsky Test of Motor Proficiency was administered before and after a three month treatment/ training session. Participants in the first experimental group received drug therapy (including methylphenidate). In the second group participants took part in 18 sessions of perceptual-motor skill training for six consecutive weeks, and in the third group children received both interventions. The results indicated that interventions using perceptual-motor training alone or in combination with a drug therapy significantly improved both gross and fine motor skills over a period of six weeks. Participants in the drug-only group showed no improvement in motor performance.

  5. Delayed perceptual awareness in rapid perceptual decisions.

    Directory of Open Access Journals (Sweden)

    Regina Gregori-Grgič

    Full Text Available The flourishing of studies on the neural correlates of decision-making calls for an appraisal of the relation between perceptual decisions and conscious perception. By exploiting the long integration time of noisy motion stimuli, and by forcing human observers to make difficult speeded decisions--sometimes a blind guess--about stimulus direction, we traced the temporal buildup of motion discrimination capability and perceptual awareness, as assessed trial by trial through direct rating. We found that both increased gradually with motion coherence and viewing time, but discrimination was systematically leading awareness, reaching a plateau much earlier. Sensitivity and criterion changes contributed jointly to the slow buildup of perceptual awareness. It made no difference whether motion discrimination was accomplished by saccades or verbal responses. These findings suggest that perceptual awareness emerges on the top of a developing or even mature perceptual decision. We argue that the middle temporal (MT cortical region does not confer us the full phenomenic depth of motion perception, although it may represent a precursor stage in building our subjective sense of visual motion.

  6. Gender, age, and educational level attribute to blood alcohol concentration in hospitalized intoxicated adolescents: A cohort study

    NARCIS (Netherlands)

    Zanten, van E.; Ploeg, van der T.; Van Hoof, Joris J.; Lely, van der Nicolaas

    2013-01-01

    Background The prevalence of adolescents hospitalized with acute alcohol intoxication, mainly because of severe reduced consciousness, is increasing. However, the characteristics of these adolescents are mainly unidentified. In this clinical research, we aimed to identify factors that attribute to h

  7. 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…

  8. Perceptual dimensions for a dynamic tactile display

    Science.gov (United States)

    Pappas, Thrasyvoulos N.; Tartter, Vivien C.; Seward, Andrew G.; Genzer, Boris; Gourgey, Karen; Kretzschmar, Ilona

    2009-02-01

    We propose a new approach for converting graphical and pictorial information into tactile patterns that can be displayed in a static or dynamic tactile device. The key components of the proposed approach are (1) an algorithm that segments a scene into perceptually uniform segments; (2) a procedure for generating perceptually distinct tactile patterns; and (3) a mapping of the visual textures of the segments into tactile textures that convey similar concepts. We used existing digital halftoning and other techniques to generate a wide variety of tactile textures. We then conducted formal and informal subjective tests with sighted (but visually blocked) and visually-impaired subjects to determine the ability of human tactile perception to perceive differences among them. In addition to generating perceptually distinguishable tactile patterns, our goal is to identify significant dimensions of tactile texture perception, which will make it possible to map different visual attributes into independent tactile attributes. Our experimental results indicate that it is poosible to generate a number of perceptually distinguishable tactile patterns, and that different dimensions of tactile texture perception can indeed be identified.

  9. Perceptual memory drives learning of retinotopic biases for bistable stimuli.

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    Aidan Peter Murphy

    2014-02-01

    Full Text Available The visual system exploits past experience at multiple timescales to resolve perceptual ambiguity in the retinal image. For example, perception of a bistable stimulus can be biased towards one interpretation over another when preceded by a brief presentation of a disambiguated version of the stimulus (positive priming or through intermittent presentations of the ambiguous stimulus (stabilization. Similarly, prior presentations of unambiguous stimuli can be used to explicitly train a long-lasting association between a percept and a retinal location (perceptual association. These phenonema have typically been regarded as independent processes, with short-term biases attributed to perceptual memory and longer-term biases described as associative learning. Here we tested for interactions between these two forms of experience-dependent perceptual bias and demonstrate that short-term processes strongly influence long-term outcomes. We first demonstrate that the establishment of long-term perceptual contingencies does not require explicit training by unambiguous stimuli, but can arise spontaneously during the periodic presentation of brief, ambiguous stimuli. Using rotating Necker cube stimuli, we observed enduring, retinotopically specific perceptual biases that were expressed from the outset and remained stable for up to forty minutes, consistent with the known phenomenon of perceptual stabilization. Further, bias was undiminished after a break period of five minutes, but was readily reset by interposed periods of continuous, as opposed to periodic, ambiguous presentation. Taken together, the results demonstrate that perceptual biases can arise naturally and may principally reflect the brain’s tendency to favor recent perceptual interpretation at a given retinal location. Further, they suggest that an association between retinal location and perceptual state, rather than a physical stimulus, is sufficient to generate long-term biases in perceptual

  10. Notebook Positioning by Perceptual Map and Laddering Method

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    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.

  11. Perceptually-Driven Signal Analysis for Acoustic Event Classification

    Science.gov (United States)

    2007-09-26

    study of musical timbre . Defined as "the subjective attribute of sound which differentiates two or more sounds that have the same loudness, pitch and...therefore a better estimate of the likelihood function. 56 Bibliography [1] J. M. Grey, -AMultidimensional perceptual scaling of musical timbres ...Display, 2005. [10] J. M. Grey, "Perceptual effects of spectral modifications on musical timbres ," Journal of the Acoustical Society of America, vol. 63

  12. Auditory perceptual simulation: Simulating speech rates or accents?

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    Zhou, Peiyun; Christianson, Kiel

    2016-07-01

    When readers engage in Auditory Perceptual Simulation (APS) during silent reading, they mentally simulate characteristics of voices attributed to a particular speaker or a character depicted in the text. Previous research found that auditory perceptual simulation of a faster native English speaker during silent reading led to shorter reading times that auditory perceptual simulation of a slower non-native English speaker. Yet, it was uncertain whether this difference was triggered by the different speech rates of the speakers, or by the difficulty of simulating an unfamiliar accent. The current study investigates this question by comparing faster Indian-English speech and slower American-English speech in the auditory perceptual simulation paradigm. Analyses of reading times of individual words and the full sentence reveal that the auditory perceptual simulation effect again modulated reading rate, and auditory perceptual simulation of the faster Indian-English speech led to faster reading rates compared to auditory perceptual simulation of the slower American-English speech. The comparison between this experiment and the data from Zhou and Christianson (2016) demonstrate further that the "speakers'" speech rates, rather than the difficulty of simulating a non-native accent, is the primary mechanism underlying auditory perceptual simulation effects.

  13. Perceptually-Inspired Computing

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    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.

  14. Perceptual grouping in pigeons.

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    Nagasaka, Yasuo; Hori, Koji; Osada, Yoshihisa

    2005-01-01

    Animal studies reveal that many species perceive partially occluded objects in the same way as do humans. Pigeons have been a notable exception. We re-investigated this anomaly of pigeon perception using a different approach from previous studies. With our method, we show that pigeons perceive occluded objects in the same manner as do other species. In addition, we report that pigeons can recognize perceptually transparent surfaces when the effect is induced by the same perceptual mechanisms as occlusion. These results give behavioral evidence that the perception of both occlusion and transparency is a common visual function shared by pigeons and humans, despite the structural differences between their visual systems.

  15. Spatial Heterogeneity in the Perception of Face and Form Attributes

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    Afraz, Arash; Pashkam, Maryam Vaziri; Cavanagh, Patrick

    2016-01-01

    Summary The identity of an object is a fixed property, independent of where it appears, and an effective visual system should capture this invariance [1–3]. However, we now report that the perceived gender of a face is strongly biased toward male or female at different locations in the visual field. The spatial pattern of these biases was distinctive and stable for each individual. Identical neutral faces looked different when they were presented simultaneously at locations maximally biased to opposite genders. A similar effect was observed for perceived age of faces. We measured the magnitude of this perceptual heterogeneity for four other visual judgments: perceived aspect ratio, orientation discrimination, spatial-frequency discrimination, and color discrimination. The effect was sizeable for the aspect ratio task but substantially smaller for the other three tasks. We also evaluated perceptual heterogeneity for facial gender and orientation tasks at different spatial scales. Strong heterogeneity was observed even for the orientation task when tested at small scales. We suggest that perceptual heterogeneity is a general property of visual perception and results from undersampling of the visual signal at spatial scales that are small relative to the size of the receptive fields associated with each visual attribute. PMID:21109440

  16. Acetylcholine and Olfactory Perceptual Learning

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    Wilson, Donald A.; Fletcher, Max L.; Sullivan, Regina M.

    2004-01-01

    Olfactory perceptual learning is a relatively long-term, learned increase in perceptual acuity, and has been described in both humans and animals. Data from recent electrophysiological studies have indicated that olfactory perceptual learning may be correlated with changes in odorant receptive fields of neurons in the olfactory bulb and piriform…

  17. State-dependent sculpting of olfactory sensory neurons is attributed to sensory enrichment, odor deprivation, and aging.

    Science.gov (United States)

    Cavallin, Melissa Ann; Powell, Katelyn; Biju, K C; Fadool, Debra Ann

    2010-10-11

    Gene-targeted deletion of the predominant Shaker potassium channel, Kv1.3, in the mitral cells of the olfactory bulb, decreases the number of presynaptic, odorant receptor (OR)-identified olfactory sensory neurons (OSNs) in the main olfactory epithelium (MOE) and alters the nature of their postsynaptic connections to mitral cell targets. The current study examined whether OSN density was state-dependent by examining the impact of (1) odor enrichment, (2) sensory deprivation, and (3) aging upon the number of P2- or M72-expressing neurons. Histological approaches were used to quantify the number of OSNs across entire epithelia for wildtype (WT) vs. Kv1.3-null (KO) mice bred onto an ORtauLacZ reporter background. Following either odor enrichment or early unilateral naris-occlusion, the number of M72-expressing OSNs was significantly decreased in WT mice, but was unchanged in KO animals. Following naris-occlusion, the number of P2-expressing OSNs was decreased regardless of genotype. Animals that were reared to 2 years of age demonstrated loss of both P2- and M72-expressing OSNs in WT mice and a concomitant loss of only M72-expressing neurons in KO mice. These findings suggest that voltage-gated activity of the mitral cells is important for OSN plasticity, and can prevent neuronal loss via sensory- and OR-dependent mechanisms.

  18. Perceptual costs for motion transparency evaluated by two performance measures.

    Science.gov (United States)

    Suzuki, Naoto; Watanabe, Osamu

    2009-08-01

    Transparency perception is recognized as one of the important phenomena to understand the computational mechanism of early visual system. Transparency perception indicates that a simple theory reconstructing a single-valued field of a visual attribute, such as an optical-flow field, cannot model the neural mechanism for the human visual system and raises a fundamental issue of how visual attributes are represented and detected in the brain. It is considered that one of the important cues to reveal the neural encoding mechanism for overlapping surfaces is the perceptual cost in transparency perception. It has been known that the perceptual performance in motion transparency is worse than that expected from single motion perception. This perceptual "cost" would reflect the encoding strategy for transparent motions. Here we present a systematic study comparing the perceptual costs in motion transparency evaluated by two performance measures. The result showed that the properties of the perceptual costs varied with the performance measures. The perceptual cost evaluated by the motion detection threshold became smaller as a directional difference between overlapping motions increased, whereas the cost examined with the precision of directional judgments became worse. A computational analysis suggests that these contradictory results cannot be explained by a simple population coding model for motion directions.

  19. 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) 1 year 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.

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

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    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.

  1. Age- and brain region-dependent α-synuclein oligomerization is attributed to alterations in intrinsic enzymes regulating α-synuclein phosphorylation in aging monkey brains.

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    Chen, Min; Yang, Weiwei; Li, Xin; Li, Xuran; Wang, Peng; Yue, Feng; Yang, Hui; Chan, Piu; Yu, Shun

    2016-02-23

    We previously reported that the levels of α-syn oligomers, which play pivotal pathogenic roles in age-related Parkinson's disease (PD) and dementia with Lewy bodies, increase heterogeneously in the aging brain. Here, we show that exogenous α-syn incubated with brain extracts from older cynomolgus monkeys and in Lewy body pathology (LBP)-susceptible brain regions (striatum and hippocampus) forms higher amounts of phosphorylated and oligomeric α-syn than that in extracts from younger monkeys and LBP-insusceptible brain regions (cerebellum and occipital cortex). The increased α-syn phosphorylation and oligomerization in the brain extracts from older monkeys and in LBP-susceptible brain regions were associated with higher levels of polo-like kinase 2 (PLK2), an enzyme promoting α-syn phosphorylation, and lower activity of protein phosphatase 2A (PP2A), an enzyme inhibiting α-syn phosphorylation, in these brain extracts. Further, the extent of the age- and brain-dependent increase in α-syn phosphorylation and oligomerization was reduced by inhibition of PLK2 and activation of PP2A. Inversely, phosphorylated α-syn oligomers reduced the activity of PP2A and showed potent cytotoxicity. In addition, the activity of GCase and the levels of ceramide, a product of GCase shown to activate PP2A, were lower in brain extracts from older monkeys and in LBP-susceptible brain regions. Our results suggest a role for altered intrinsic metabolic enzymes in age- and brain region-dependent α-syn oligomerization in aging brains.

  2. Stripes Do Not a Zebra Make, or Do They? Conceptual and Perceptual Information in Inductive Inference.

    Science.gov (United States)

    Florian, Judy E.

    1994-01-01

    Four-year-olds' and adults' inferences based on shared conceptual properties, category labels, and perceptual information were assessed in four experiments. Stimuli included novel and familiar animals. Found that children made attribute-based inductions as well as category-based inductions, and that perceptual similarity consistently influenced…

  3. Number As a Primary Perceptual Attribute: A Review.

    Science.gov (United States)

    Anobile, Giovanni; Cicchini, Guido Marco; Burr, David C

    2016-01-01

    Although humans are the only species to possess language-driven abstract mathematical capacities, we share with many other animals a nonverbal capacity for estimating quantities or numerosity. For some time, researchers have clearly differentiated between small numbers of items--less than about four--referred to as the subitizing range, and larger numbers, where counting or estimation is required. In this review, we examine more recent evidence suggesting a further division, between sets of items greater than the subitizing range, but sparse enough to be individuated as single items; and densely packed stimuli, where they crowd each other into what is better considered as a texture. These two different regimes are psychophysically discriminable in that they follow distinct psychophysical laws and show different dependencies on eccentricity and on luminance levels. But provided the elements are not too crowded (less than about two items per square degree in central vision, less in the periphery), there is little evidence that estimation of numerosity depends on mechanisms responsive to texture. The distinction is important, as the ability to discriminate numerosity, but not texture, correlates with formal maths skills.

  4. Exploring Perceptual Skills in Children with Autism Spectrum Disorders: From Target Detection to Dynamic Perceptual Discrimination

    Science.gov (United States)

    Miller, Louisa; McGonigle-Chalmers, Maggie

    2014-01-01

    Perceptual processing in autism is associated with both "strengths" and "weaknesses" but within a literature that varies widely in terms of the assessments used. We report data from 12 children with autism spectrum disorders (ASD) and 12 age and IQ matched neurotypical controls tested on a set of tasks using the same stimuli…

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

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    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.

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

    Science.gov (United States)

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

    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 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. PMID:25774507

  7. Two Thirds of the Age-Based Changes in Fluid and Crystallized Intelligence, Perceptual Speed, and Memory in Adulthood Are Shared

    Science.gov (United States)

    Ghisletta, Paolo; Rabbitt, Patrick; Lunn, Mary; Lindenberger, Ulman

    2012-01-01

    Many aspects of cognition decline from middle to late adulthood, but the dimensionality and generality of this decline have rarely been examined. We analyzed 20-year longitudinal data of 6203 middle-aged to very old adults from Greater Manchester and Newcastle-upon-Tyne, UK. Participants were assessed up to eight times on 20 tasks of fluid…

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

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    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.

  9. Perceptual Audio Hashing Functions

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    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.

  10. Unifying Perceptual Learning

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    Philip J. Kellman

    2011-05-01

    Full Text Available What is the relation between perceptual learning (PL in basic sensory discriminations and in more complex tasks, including real-world learning tasks? Most recent PL work focuses on the former, using simple sensory dimensions and a few specific stimulus values. In contrast, other PL research and virtually all real-world tasks involve discovery of invariance amidst variation, and may also involve PL working synergistically with other cognitive abilities. In this talk I will suggest that, despite superficial differences, low- and high-level PL tasks draw upon—and reveal—a unified type of learning. I will consider several arguments that have been advanced in favor of confining perceptual learning to plasticity at the earliest cortical levels along with models of PL based on receptive field change vs. selection. These analyses do not support the idea of a separate low-level process but do support both the abstract character of PL and its dependence on unifying notions of discovery and selection. In the final part of the talk, I will relate this unified view of PL to direct practical applications. Learning technology based on PL modules (PLMs can address elusive aspects of learning, including pattern recognition, transfer, and fluency, even in high-level, symbolic domains, such as mathematics learning.

  11. Perceptualization of scientific data

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    Grinstein, Georges G.; Smith, Stuart

    1990-08-01

    In this paper we discuss data exploration as a particularly difficult case within the general problem of data visualization. We describe (1) a novel graphic technique for displaying multidimensional data visually and (2) an auditory display integrated with the visual display that allows us to represent multidimensional data in sound. The visual/auditory display employs an "iconographic" technique that seeks to exploit the spontaneous perceptual capacity to sense and discriminate texture. Structures in data to be analyzed can appear, both visually and aurally, as distinct textural regions and contours when the data are represented iconographically. Sound can be used to reinforce the visual presentation or to augment the dimensionality of the visual display. The immediate focus of the work reported here is to investigate how best to transform data into perceptible visual and auditory textures, that is, how best to "perceptualize" the data. A key problem we discuss is deciding which fields of a multidimensional data set should be represented in the visual domain and which in the auditory domain. This activity is part of the University of Lowell's Exploratory Visualization (Exvis) project, a multidisciplinary effort to develop new paradigms for the exploration and analysis of data with high dimensionality.

  12. Conflict-Induced Perceptual Filtering

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    Wendt, Mike; Luna-Rodriguez, Aquiles; Jacobsen, Thomas

    2012-01-01

    In a variety of conflict paradigms, target and distractor stimuli are defined in terms of perceptual features. Interference evoked by distractor stimuli tends to be reduced when the ratio of congruent to incongruent trials is decreased, suggesting conflict-induced perceptual filtering (i.e., adjusting the processing weights assigned to stimuli…

  13. Perceptual basis for reactive teleoperation.

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    Park, Y. S.; Ewing, T. F.; Boyle, J. M.; Yule, T. J.

    2001-08-28

    To enhance task performance in partially structured environment, enhancement of teleoperation was proposed by introducing autonomous behaviors. Such autonomy is implemented based on reactive robotic architecture, where reactive motor agents that directly couples sensory inputs and motor actions become the building blocks. To this end, presented in this paper is a perceptual basis for the motor agents. The perceptual basis consists of perceptual agents that extracts environmental information from a structured light vision system and provide action oriented perception for the corresponding motor agents. Rather than performing general scene reconstruction, a perceptual agent directly provides the motion reference for the motor behavior. Various sensory mechanisms--sensor fission, fusion, and fashion--becomes basic building blocks of the perception process. Since perception is a process deeply intertwined with the motor actions, active perception may also incorporate motor behaviors as an integral perceptual process.

  14. Perceptual learning in sensorimotor adaptation.

    Science.gov (United States)

    Darainy, Mohammad; Vahdat, Shahabeddin; Ostry, David J

    2013-11-01

    Motor learning often involves situations in which the somatosensory targets of movement are, at least initially, poorly defined, as for example, in learning to speak or learning the feel of a proper tennis serve. Under these conditions, motor skill acquisition presumably requires perceptual as well as motor learning. That is, it engages both the progressive shaping of sensory targets and associated changes in motor performance. In the present study, we test the idea that perceptual learning alters somatosensory function and in so doing produces changes to human motor performance and sensorimotor adaptation. Subjects in these experiments undergo perceptual training in which a robotic device passively moves the subject's arm on one of a set of fan-shaped trajectories. Subjects are required to indicate whether the robot moved the limb to the right or the left and feedback is provided. Over the course of training both the perceptual boundary and acuity are altered. The perceptual learning is observed to improve both the rate and extent of learning in a subsequent sensorimotor adaptation task and the benefits persist for at least 24 h. The improvement in the present studies varies systematically with changes in perceptual acuity and is obtained regardless of whether the perceptual boundary shift serves to systematically increase or decrease error on subsequent movements. The beneficial effects of perceptual training are found to be substantially dependent on reinforced decision-making in the sensory domain. Passive-movement training on its own is less able to alter subsequent learning in the motor system. Overall, this study suggests perceptual learning plays an integral role in motor learning.

  15. 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...

  16. Perceptual consequences of "hidden" hearing loss.

    Science.gov (United States)

    Plack, Christopher J; Barker, Daphne; Prendergast, Garreth

    2014-09-09

    Dramatic results from recent animal experiments show that noise exposure can cause a selective loss of high-threshold auditory nerve fibers without affecting absolute sensitivity permanently. This cochlear neuropathy has been described as hidden hearing loss, as it is not thought to be detectable using standard measures of audiometric threshold. It is possible that hidden hearing loss is a common condition in humans and may underlie some of the perceptual deficits experienced by people with clinically normal hearing. There is some evidence that a history of noise exposure is associated with difficulties in speech discrimination and temporal processing, even in the absence of any audiometric loss. There is also evidence that the tinnitus experienced by listeners with clinically normal hearing is associated with cochlear neuropathy, as measured using Wave I of the auditory brainstem response. To date, however, there has been no direct link made between noise exposure, cochlear neuropathy, and perceptual difficulties. Animal experiments also reveal that the aging process itself, in the absence of significant noise exposure, is associated with loss of auditory nerve fibers. Evidence from human temporal bone studies and auditory brainstem response measures suggests that this form of hidden loss is common in humans and may have perceptual consequences, in particular, regarding the coding of the temporal aspects of sounds. Hidden hearing loss is potentially a major health issue, and investigations are ongoing to identify the causes and consequences of this troubling condition.

  17. Perceptual Load Modulates Object-Based Attention

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    Ho, Ming-Chou; Atchley, Paul

    2009-01-01

    Two experimental series are reported using both reaction time (RT) and a data-limited perceptual report to examine the effects of perceptual load on object-based attention. Perceptual load was manipulated across 3 levels by increasing the complexity of perceptual judgments. Data from the RT-based experiments showed object-based effects when the…

  18. Promoting Positive Learning in Australian Students Aged 10- to 12-Years-Old Using Attribution Retraining and Cognitive Behavioral Therapy: A Pilot Study

    Science.gov (United States)

    Chodkiewicz, Alicia R; Boyle, Christopher

    2016-01-01

    This study piloted an intervention using attribution retraining and cognitive behavioral therapy techniques to promote positive learning experiences and outcomes for students. This research is an important step to revitalise the dwindling field of attribution retraining research by assessing whether these techniques effectively improve student…

  19. 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.

  20. 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)…

  1. Toward a perceptual theory of transparency.

    Science.gov (United States)

    Singh, Manish; Anderson, Barton L

    2002-07-01

    Theories of perceptual transparency have typically been developed within the context of a physical model that generates the percept of transparency (F. Metelli's episcotister model, 1974b). Here 2 fundamental questions are investigated: (a) When does the visual system initiate the percept of one surface seen through another? (b) How does it assign surface properties to a transparent layer? Results reveal systematic deviations from the predictions of Metelli's model, both for initiating image decomposition into multiple surfaces and for assigning surface attributes. Specifically, results demonstrate that the visual system uses Michelson contrast as a critical image variable to initiate percepts of transparency and to assign transmittance to transparent surfaces. Findings are discussed in relation to previous theories of transparency, lightness, brightness, and contrast-contrast.

  2. Perceptual learning of degraded speech by minimizing prediction error.

    Science.gov (United States)

    Sohoglu, Ediz; Davis, Matthew H

    2016-03-22

    Human perception is shaped by past experience on multiple timescales. Sudden and dramatic changes in perception occur when prior knowledge or expectations match stimulus content. These immediate effects contrast with the longer-term, more gradual improvements that are characteristic of perceptual learning. Despite extensive investigation of these two experience-dependent phenomena, there is considerable debate about whether they result from common or dissociable neural mechanisms. Here we test single- and dual-mechanism accounts of experience-dependent changes in perception using concurrent magnetoencephalographic and EEG recordings of neural responses evoked by degraded speech. When speech clarity was enhanced by prior knowledge obtained from matching text, we observed reduced neural activity in a peri-auditory region of the superior temporal gyrus (STG). Critically, longer-term improvements in the accuracy of speech recognition following perceptual learning resulted in reduced activity in a nearly identical STG region. Moreover, short-term neural changes caused by prior knowledge and longer-term neural changes arising from perceptual learning were correlated across subjects with the magnitude of learning-induced changes in recognition accuracy. These experience-dependent effects on neural processing could be dissociated from the neural effect of hearing physically clearer speech, which similarly enhanced perception but increased rather than decreased STG responses. Hence, the observed neural effects of prior knowledge and perceptual learning cannot be attributed to epiphenomenal changes in listening effort that accompany enhanced perception. Instead, our results support a predictive coding account of speech perception; computational simulations show how a single mechanism, minimization of prediction error, can drive immediate perceptual effects of prior knowledge and longer-term perceptual learning of degraded speech.

  3. Perceptual learning: top to bottom.

    Science.gov (United States)

    Amitay, Sygal; Zhang, Yu-Xuan; Jones, Pete R; Moore, David R

    2014-06-01

    Perceptual learning has traditionally been portrayed as a bottom-up phenomenon that improves encoding or decoding of the trained stimulus. Cognitive skills such as attention and memory are thought to drive, guide and modulate learning but are, with notable exceptions, not generally considered to undergo changes themselves as a result of training with simple perceptual tasks. Moreover, shifts in threshold are interpreted as shifts in perceptual sensitivity, with no consideration for non-sensory factors (such as response bias) that may contribute to these changes. Accumulating evidence from our own research and others shows that perceptual learning is a conglomeration of effects, with training-induced changes ranging from the lowest (noise reduction in the phase locking of auditory signals) to the highest (working memory capacity) level of processing, and includes contributions from non-sensory factors that affect decision making even on a "simple" auditory task such as frequency discrimination. We discuss our emerging view of learning as a process that increases the signal-to-noise ratio associated with perceptual tasks by tackling noise sources and inefficiencies that cause performance bottlenecks, and present some implications for training populations other than young, smart, attentive and highly-motivated college students.

  4. Effects of Perceptual Variations on Number Comparison Tasks.

    Science.gov (United States)

    Kingma, Johannes; Loth, Franciska L.

    1984-01-01

    Investigates the performance of 502 children ranging in age from four years to six years, ten months, on two-choice and multiple-choice number comparison tasks, and explores the effects of perceptual manipulations of elements in the multiple-choice tasks. (RH)

  5. 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

  6. Auditory perceptual load: A review.

    Science.gov (United States)

    Murphy, Sandra; Spence, Charles; Dalton, Polly

    2017-02-08

    Selective attention is a crucial mechanism in everyday life, allowing us to focus on a portion of incoming sensory information at the expense of other less relevant stimuli. The circumstances under which irrelevant stimuli are successfully ignored have been a topic of scientific interest for several decades now. Over the last 20 years, the perceptual load theory (e.g. Lavie, 1995) has provided one robust framework for understanding these effects within the visual modality. The suggestion is that successful selection depends on the perceptual demands imposed by the task-relevant information. However, less research has addressed the question of whether the same principles hold in audition and, to date, the existing literature provides a mixed picture. Here, we review the evidence for and against the applicability of perceptual load theory in hearing, concluding that this question still awaits resolution.

  7. 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.

  8. Hemispheric asymmetries in the perceptual representations of words.

    Science.gov (United States)

    Lincoln, Amy E; Long, Debra L; Swick, Diane; Larsen, Jary; Baynes, Kathleen

    2008-01-10

    The representation of words in sentences can involve the activation and integration of perceptual information. For example, readers who are asked to view pictures of objects relating to a word in a sentence are influenced by perceptual information in the sentence context-readers are faster to respond to a picture of a whole apple after reading, "There is an apple in the bag," than after reading, "There is an apple in the salad." The purpose of this study was to examine how the two cerebral hemispheres use perceptual information about words as a function of sentence context. Patients who had damage to the left or right hemisphere and age-matched control participants read sentences that described, but did not entail, the shape or state of an object. They then made recognition judgments to pictures that either matched or mismatched the perceptual form implied by the sentence. Responses and latencies were examined for a match effect -- faster and more accurate responses to pictures in the match than mismatch condition -- controlling for comprehension ability and lesion size. When comprehension ability and lesion size are properly controlled, left-hemisphere-damaged patients and control participants exhibited the expected match effect, whereas right-hemisphere-damaged participants showed no effect of match condition. These results are consistent with research implicating the right hemisphere in the representation of contextually relevant perceptual information.

  9. Predicting Social and Communicative Ability in School-Age Children with Autism Spectrum Disorder: A Pilot Study of the Social Attribution Task, Multiple Choice

    Science.gov (United States)

    Burger-Caplan, Rebecca; Saulnier, Celine; Jones, Warren; Klin, Ami

    2016-01-01

    The Social Attribution Task, Multiple Choice is introduced as a measure of implicit social cognitive ability in children, addressing a key challenge in quantification of social cognitive function in autism spectrum disorder, whereby individuals can often be successful in explicit social scenarios, despite marked social adaptive deficits. The…

  10. Conformity in the Asch task as a function of age.

    Science.gov (United States)

    Walker, M B; Andrade, M G

    1996-06-01

    The social conformity paradigm of Asch (1956) was replicated to investigate the relationship between age and conformist behavior. One hundred ten Australian school children and adolescents between 3 and 17 years of age participated in the study. Each participant was placed in the position of being a minority of 1 against a wrong but unanimous majority of 3. The results indicate that conformity decreases with age in perceptually unambiguous tasks. Conflicting evidence from earlier studies can be attributed to task ambiguity in those studies.

  11. Perceptual transparency from image deformation.

    Science.gov (United States)

    Kawabe, Takahiro; Maruya, Kazushi; Nishida, Shin'ya

    2015-08-18

    Human vision has a remarkable ability to perceive two layers at the same retinal locations, a transparent layer in front of a background surface. Critical image cues to perceptual transparency, studied extensively in the past, are changes in luminance or color that could be caused by light absorptions and reflections by the front layer, but such image changes may not be clearly visible when the front layer consists of a pure transparent material such as water. Our daily experiences with transparent materials of this kind suggest that an alternative potential cue of visual transparency is image deformations of a background pattern caused by light refraction. Although previous studies have indicated that these image deformations, at least static ones, play little role in perceptual transparency, here we show that dynamic image deformations of the background pattern, which could be produced by light refraction on a moving liquid's surface, can produce a vivid impression of a transparent liquid layer without the aid of any other visual cues as to the presence of a transparent layer. Furthermore, a transparent liquid layer perceptually emerges even from a randomly generated dynamic image deformation as long as it is similar to real liquid deformations in its spatiotemporal frequency profile. Our findings indicate that the brain can perceptually infer the presence of "invisible" transparent liquids by analyzing the spatiotemporal structure of dynamic image deformation, for which it uses a relatively simple computation that does not require high-level knowledge about the detailed physics of liquid deformation.

  12. Perceptual Fading without Retinal Adaptation

    Science.gov (United States)

    Hsieh, Po-Jang; Colas, Jaron T.

    2012-01-01

    A retinally stabilized object readily undergoes perceptual fading and disappears from consciousness. This startling phenomenon is commonly believed to arise from local bottom-up sensory adaptation to edge information that occurs early in the visual pathway, such as in the lateral geniculate nucleus of the thalamus or retinal ganglion cells. Here…

  13. Dichotomy and perceptual distortions in absolute pitch ability.

    Science.gov (United States)

    Athos, E Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane

    2007-09-11

    Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a "perceptual magnet" centered at the note "A." In addition, we document a gradual decline in pitch-naming accuracy with age, characterized by a perceptual shift in the "sharp" direction. These findings speak both to the process of acquisition of AP and to its stability.

  14. 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.

  15. Consequences of comorbidity of developmental coordination disorders and learning disabilities for severity and pattern of perceptual-motor dysfunction.

    Science.gov (United States)

    Jongmans, Marian J; Smits-Engelsman, Bouwien C M; Schoemaker, Marina M

    2003-01-01

    Children with developmental coordination disorder (DCD) have difficulty learning and performing age-appropriate perceptual-motor skills in the absence of diagnosable neurological disorders. Descriptive studies have shown that comorbidity of DCD exists with attention-deficit/hyperactivity disorder (ADHD) and learning disabilities (LD). This study examined the consequences of the comorbidity of DCD and LD for the severity and pattern of perceptual-motor dysfunction. Compared to children with DCD without LD, children with comorbid DCD and LD performed lower on a standardized assessment of perceptual-motor ability. Furthermore, it appeared that children with combined DCD and LD have particular difficulty performing manual dexterity and balance tasks but not ball-skill tasks. Implications for understanding the relationship between LD and perceptual-motor problems are discussed. We conclude that the comorbidity of DCD and LD not only affects the severity of perceptual-motor dysfunction but also is associated with a distinctive pattern of perceptual-motor dysfunction.

  16. Perceptual Color Characterization of Cameras

    Directory of Open Access Journals (Sweden)

    Javier Vazquez-Corral

    2014-12-01

    Full Text Available Color camera characterization, mapping outputs from the camera sensors to an independent color space, such as \\(XYZ\\, is an important step in the camera processing pipeline. Until now, this procedure has been primarily solved by using a \\(3 \\times 3\\ matrix obtained via a least-squares optimization. In this paper, we propose to use the spherical sampling method, recently published by Finlayson al., to perform a perceptual color characterization. In particular, we search for the \\(3 \\times 3\\ matrix that minimizes three different perceptual errors, one pixel based and two spatially based. For the pixel-based case, we minimize the CIE \\(\\Delta E\\ error, while for the spatial-based case, we minimize both the S-CIELAB error and the CID error measure. Our results demonstrate an improvement of approximately 3for the \\(\\Delta E\\ error, 7& for the S-CIELAB error and 13% for the CID error measures.

  17. Perceptual and cognitive spatial learning.

    Science.gov (United States)

    Bedford, F L

    1993-06-01

    Ss were taught novel mappings between visual space and motor space with either a variant on a prism adaptation paradigm (Experiments 1 and 2) or a nonperceptual cognitive task (Experiments 3 and 4). First, discrimination training specified that 1 visual location required a new pointing response but another location did not. This led to unusual generalization unlike typical generalization decrement. Second, training at 9 locations specified that 1 location required a new response but that the remaining 8 did not. This simple isolation mapping was unlearnable and instead a flat function fit through all of space. In contrast, for the cognitive paradigm, not only was isolation of one region of space easily learned, it was the preferred pattern of generalization. Implications for perceptual learning, as well as the qualitative distinctions between perceptual and cognitive learning, are discussed.

  18. Generalization of multisensory perceptual learning

    Science.gov (United States)

    Powers III, Albert R.; Hillock-Dunn, Andrea; Wallace, Mark T.

    2016-01-01

    Life in a multisensory world requires the rapid and accurate integration of stimuli across the different senses. In this process, the temporal relationship between stimuli is critical in determining which stimuli share a common origin. Numerous studies have described a multisensory temporal binding window—the time window within which audiovisual stimuli are likely to be perceptually bound. In addition to characterizing this window’s size, recent work has shown it to be malleable, with the capacity for substantial narrowing following perceptual training. However, the generalization of these effects to other measures of perception is not known. This question was examined by characterizing the ability of training on a simultaneity judgment task to influence perception of the temporally-dependent sound-induced flash illusion (SIFI). Results do not demonstrate a change in performance on the SIFI itself following training. However, data do show an improved ability to discriminate rapidly-presented two-flash control conditions following training. Effects were specific to training and scaled with the degree of temporal window narrowing exhibited. Results do not support generalization of multisensory perceptual learning to other multisensory tasks. However, results do show that training results in improvements in visual temporal acuity, suggesting a generalization effect of multisensory training on unisensory abilities. PMID:27000988

  19. 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

  20. Social attributions from faces: determinants, consequences, accuracy, and functional significance.

    Science.gov (United States)

    Todorov, Alexander; Olivola, Christopher Y; Dotsch, Ron; Mende-Siedlecki, Peter

    2015-01-03

    Since the early twentieth century, psychologists have known that there is consensus in attributing social and personality characteristics from facial appearance. Recent studies have shown that surprisingly little time and effort are needed to arrive at this consensus. Here we review recent research on social attributions from faces. Section I outlines data-driven methods capable of identifying the perceptual basis of consensus in social attributions from faces (e.g., What makes a face look threatening?). Section II describes nonperceptual determinants of social attributions (e.g., person knowledge and incidental associations). Section III discusses evidence that attributions from faces predict important social outcomes in diverse domains (e.g., investment decisions and leader selection). In Section IV, we argue that the diagnostic validity of these attributions has been greatly overstated in the literature. In the final section, we offer an account of the functional significance of these attributions.

  1. 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 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...... are encouraging, suggesting that efforts to optimize the perceived built and social environment may act in a socially-equitable manner to facilitate MVPA....

  2. 压抑与遮盖在视感知疗法治疗学龄期儿童屈光参差性弱视中的疗效比较研究%Comparison of the effect between penalization and occlusion in the perceptu al learning for treatm ent of scholo-age children with ani sometropic amblyopia

    Institute of Scientific and Technical Information of China (English)

    孔旻; 林泉; 赵武校; 刘伟民

    2013-01-01

    目的:比较研究视感知疗法在学龄期儿童屈光参差性弱视中使用压抑与遮盖法的疗效。方法将78例(155眼)学龄期儿童屈光参差性弱视患者,分别行压抑(43例,85眼)和遮盖(35例,70眼)法矫正视力较好眼,使用视感知疗法治疗1年后应用统计学分析疗效。结果压抑法的疗效优于遮盖法(P<0.05),总有效率也高于遮盖法(P<0.05),在轻、中度弱视患者中,压抑法的疗效均优于遮盖法(P<0.05),而在重度患者中,两组疗效比较差异无统计学意义( P>0.05)。结论在采用视感知疗法治疗学龄儿童屈光参差性弱视患者中,压抑法矫正视力的效果比遮盖法要好。%Obej ctive To compare the effect between penalization and occlusion in the perceptual learning for treatment of school-age children with anisometropic amblyopia .Methods In the perceptual learning for treatment of school-age children with anisometropic amblyopia ,85 eyes of 43 patients received the penalization ( penalization group) and 70 eyes of 35 patients received the occlusion(occlusion group).After 1 year researching was analyzed. Results The effects of the penalization group were better than the occlusion′s,the effects in both slight and moderate amblyopia of the penalization group also better than occlusion′s,their difference had the statistical significance ( P0.05 ) .Conclusion In the perceptual learning for treatment of school-age children with anisometropic amblyopia ,u-sing the penalization may have higher total effect than using the occlusion .

  3. Quick linguistic representations and precise perceptual representations : Language statistics and perceptual simulations under time constraints

    NARCIS (Netherlands)

    Hutchinson, S; Tillman, R.N.; Louwerse, M.M.

    2014-01-01

    Many studies have argued that language comprehension requires perceptual simulation. In previous work we have demonstrated that because language encodes perceptual relations, comprehenders can also rely on language statistics to bootstrap meaning through limited grounding. The extent comprehenders d

  4. Predicting perceptual learning from higher-order cortical processing.

    Science.gov (United States)

    Wang, Fang; Huang, Jing; Lv, Yaping; Ma, Xiaoli; Yang, Bin; Wang, Encong; Du, Boqi; Li, Wu; Song, Yan

    2016-01-01

    Visual perceptual learning has been shown to be highly specific to the retinotopic location and attributes of the trained stimulus. Recent psychophysical studies suggest that these specificities, which have been associated with early retinotopic visual cortex, may in fact not be inherent in perceptual learning and could be related to higher-order brain functions. Here we provide direct electrophysiological evidence in support of this proposition. In a series of event-related potential (ERP) experiments, we recorded high-density electroencephalography (EEG) from human adults over the course of learning in a texture discrimination task (TDT). The results consistently showed that the earliest C1 component (68-84ms), known to reflect V1 activity driven by feedforward inputs, was not modulated by learning regardless of whether the behavioral improvement is location specific or not. In contrast, two later posterior ERP components (posterior P1 and P160-350) over the occipital cortex and one anterior ERP component (anterior P160-350) over the prefrontal cortex were progressively modified day by day. Moreover, the change of the anterior component was closely correlated with improved behavioral performance on a daily basis. Consistent with recent psychophysical and imaging observations, our results indicate that perceptual learning can mainly involve changes in higher-level visual cortex as well as in the neural networks responsible for cognitive functions such as attention and decision making.

  5. Cerebellar tDCS dissociates the timing of perceptual decisions from perceptual change in speech

    NARCIS (Netherlands)

    Lametti, D.R.; Oostwoud Wijdenes, L.; Bonaiuto, J.; Bestmann, S.; Rothwell, J.C.

    2016-01-01

    Neuroimaging studies suggest that the cerebellum might play a role in both speech perception and speech perceptual learning. However, it remains unclear what this role is: does the cerebellum directly contribute to the perceptual decision? Or does it contribute to the timing of perceptual decisions?

  6. The Perceptual Basis of Vast Space.

    Science.gov (United States)

    Klatzky, Roberta L; Thompson, William B; Stefanucci, Jeanine K; Gill, Devin; McGee, D Kevin

    2017-03-20

    "Vast" is a word often applied to environmental terrain that is perceived to have large spatial extent. This judgment is made even at viewing distances where traditional metric depth cues are not useful. This paper explores the perceptual basis of vast experience, including reliability and visual precursors. Experiment 1 demonstrated strong agreement in ratings of the spatial extent of two-dimensional (2D) scene images by participants in two countries under very different viewing conditions. Image categories labeled "vast" often exemplified scene attributes of ruggedness and openness (Oliva & Torralba, 2001). Experiment 2 quantitatively assessed whether these properties predict vastness. High vastness ratings were associated with highly open, or moderately open but rugged, scenes. Experiment 3 provided evidence, consistent with theory, that metric distance perception does not directly mediate the observed vastness ratings. The question remains as to how people perceive vast space when information about environmental scale is unavailable from metric depth cues or associated scene properties. We consider possible answers, including contribution from strong cues to relative depth.

  7. Perceptual hashing algorithms benchmark suite

    Institute of Scientific and Technical Information of China (English)

    Zhang Hui; Schmucker Martin; Niu Xiamu

    2007-01-01

    Numerous perceptual hashing algorithms have been developed for identification and verification of multimedia objects in recent years. Many application schemes have been adopted for various commercial objects. Developers and users are looking for a benchmark tool to compare and evaluate their current algorithms or technologies. In this paper, a novel benchmark platform is presented. PHABS provides an open framework and lets its users define their own test strategy, perform tests, collect and analyze test data. With PHABS, various performance parameters of algorithms can be tested, and different algorithms or algorithms with different parameters can be evaluated and compared easily.

  8. 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…

  9. Graphemes are perceptual reading units.

    Science.gov (United States)

    Rey, A; Ziegler, J C; Jacobs, A M

    2000-04-14

    Graphemes are commonly defined as the written representation of phonemes. For example, the word 'BREAD' is composed of the four phonemes /b/, /r/, /e/ and /d/, and consequently, of the four graphemes 'B', 'R', 'EA', and 'D'. Graphemes can thus be considered the minimal 'functional bridges' in the mapping between orthography and phonology. In the present study, we investigated the hypothesis that graphemes are processed as perceptual units by the reading system. If the reading system processes graphemes as units, then detecting a letter in a word should be harder when this letter is embedded in a multi-letter grapheme than when it corresponds to a single-letter grapheme. In Experiment 1A, done in English, participants were slower to detect a target letter in a word when the target letter was embedded in multi-letter grapheme (i.e. 'A' in 'BEACH') than when it corresponded to a single-letter grapheme (i.e. 'A' in 'PLACE'). In Experiment 1B, this effect was replicated in French. In Experiment 2, done in English, this grapheme effect remained when phonemic similarity between the target letter alone and the target letter inside the word was controlled. Together, the results are consistent with the assumption that graphemes are processed as perceptual reading units in alphabetic writing systems such as English or French.

  10. Task-irrelevant perceptual expertise.

    Science.gov (United States)

    Wong, Yetta K; Folstein, Jonathan R; Gauthier, Isabel

    2011-12-05

    Perceptual learning (PL) and perceptual expertise (PE) are two fields of visual training studies that investigate how practice improves visual performance. However, previous research suggests that PL can be acquired in a task-irrelevant manner while PE cannot and that PL is highly specific to the training objects and conditions while PE generalizes. These differences are difficult to interpret since PL and PE studies tend to differ on multiple dimensions. We designed a training study with novel objects to compare PL and PE while varying only the training task, such that the training objects, visual field, training duration, and type of learning assessment were kept constant. Manipulations of the training task sufficed to produce the standard effects obtained in PE and PL. In contrast to prior studies, we demonstrated that some degree of PE can be acquired in a task-irrelevant manner, similar to PL. Task-irrelevant PE resulted in similar shape matching ability compared to the directly trained PE. In addition, learning in both PE and PL generalizes to different untrained conditions, which does not support the idea that PE generalizes while PL is specific. Degrees of generalization can be explained by considering the psychological space of the stimuli used for training and the test of transfer.

  11. Building online brand perceptual map.

    Science.gov (United States)

    Chiang, I-Ping; Lin, Chih-Ying; Wang, Kaisheng M

    2008-10-01

    Many companies have launched their products or services online as a new business focus, but only a few of them have survived the competition and made profits. The most important key to an online business's success is to create "brand value" for the customers. Although the concept of online brand has been discussed in previous studies, there is no empirical study on the measurement of online branding. As Web 2.0 emerges to be critical to online branding, the purpose of this study was to measure Taiwan's major Web sites with a number of personality traits to build a perceptual map for online brands. A pretest identified 10 most representative online brand perceptions. The results of the correspondence analysis showed five groups in the perceptual map. This study provided a practical view of the associations and similarities among online brands for potential alliance or branding strategies. The findings also suggested that brand perceptions can be used with identified consumer needs and behaviors to better position online services. The brand perception map in the study also contributed to a better understanding of the online brands in Taiwan.

  12. Semantic Representations in 3D Perceptual Space

    Directory of Open Access Journals (Sweden)

    Suncica Zdravkovic

    2011-05-01

    Full Text Available Barsalou's (1999 perceptual theory of knowledge echoes the pre-20th century tradition of conceptualizing all knowledge as inherently perceptual. Hence conceptual space has an infinite number of dimensions and heavily relies on perceptual experience. Osgood's (1952 semantic differential technique was developed as a bridge between perception and semantics. We updated Osgood's methodology in order to investigate current issues in visual cognition by: (1 using a 2D rather than a 1D space to place the concepts, (2 having dimensions that were perceptual while the targets were conceptual, (3 coupling visual experience with another two perceptual domains (audition and touch, (4 analyzing the data using MDS (not factor analysis. In three experiments, subjects (N = 57 judged five concrete and five abstract words on seven bipolar scales in three perceptual modalities. The 2D space led to different patterns of response compared to the classic 1D space. MDS revealed that perceptual modalities are not equally informative for mapping word-meaning distances (Mantel min = −.23; Mantel max = .88. There was no reliable differences due to test administration modality (paper vs. computer, nor scale orientation. The present findings are consistent with multidimensionality of conceptual space, a perceptual basis for knowledge, and dynamic characteristics of concepts discussed in contemporary theories.

  13. Perceptual Fusion in Humans and Machines

    NARCIS (Netherlands)

    Salah, A.A.; Tanrı dağ , O.

    2008-01-01

    Humans perceive the world through different perceptual modalities, which are processed in the brain by modality-specific areas and structures. However, there also exist multimodal neurons and areas, specialized in integrating perceptual information to enhance or suppress brain response. The particu

  14. Reduct and Attribute Order

    Institute of Scientific and Technical Information of China (English)

    Su-Qing Han; Jue Wang

    2004-01-01

    Based on the principle of discernibility matrix,a kind of reduction algorithm with attribute order has been developed and its solution has been proved to be complete for reduct and unique for a given attribute order.Being called the reduct problem,this algorithm can be regarded as a mapping R = Reduct(S)from the attribute order space θ to the reduct space R for an information system ,where U is the universe and C and D are two sets of condition and decision attributes respectively.This paper focuses on the reverse problem of reduct problem S = Order(R),i.e.,for a given reduct R of an information system,we determine the solution of S = Order(R)in the space θ.First,we need to prove that there is at least one attribute order S such that S = Order(R).Then,some decision rules are proposed,which can be used directly to decide whether the pair of attribute orders has the same reduct.The main method is based on the fact that an attribute order can be transformed into another one by moving the attribute for limited times.Thus,the decision of the pair of attribute orders can be altered to the decision of the sequence of neighboring pairs of attribute orders.Therefore,the basic theorem of neighboring pair of attribute orders is first proved,then,the decision theorem of attribute order is proved accordingly by the second attribute.

  15. Visual perceptual abilities of Chinese-speaking and English-speaking children.

    Science.gov (United States)

    Lai, Mun Yee; Leung, Frederick Koon Shing

    2012-04-01

    This paper reports an investigation of Chinese-speaking and English-speaking children's general visual perceptual abilities. The Developmental Test of Visual Perception was administered to 41 native Chinese-speaking children of mean age 5 yr. 4 mo. in Hong Kong and 35 English-speaking children of mean age 5 yr. 2 mo. in Melbourne. Of interest were the two interrelated components of visual perceptual abilities, namely, motor-reduced visual perceptual and visual-motor integration perceptual abilities, which require either verbal or motoric responses in completing visual tasks. Chinese-speaking children significantly outperformed the English-speaking children on general visual perceptual abilities. When comparing the results of each of the two different components, the Chinese-speaking students' performance on visual-motor integration was far better than that of their counterparts (ES = 2.70), while the two groups of students performed similarly on motor-reduced visual perceptual abilities. Cultural factors such as written language format may be contributing to the enhanced performance of Chinese-speaking children's visual-motor integration abilities, but there may be validity questions in the Chinese version.

  16. The Relationship Between Perceptual Motor Skills and Attention

    Directory of Open Access Journals (Sweden)

    Vanessa de Sousa

    Full Text Available Abstract: Although the relationship between perceptual motor skills and attention is reported in the literature, few studies have empirically explored this association. Thus, the objective of this study was to investigate the relationship between these constructs, using the Bender-Gestalt Test: Gradual Scoring System (B-SPG and the Psychological Battery for Attention Assessment (BPA. The participants were 320 children from four public schools in a city located in the South of the state of Minas Gerais, with ages ranging from seven to 10 years (M = 8.39, SD = 1.10 and 196 (55.9 % female. The results showed negative, moderate and significant correlations between the total scores of the instruments, indicating the relationship between the constructs. Although the data has confirmed the existence of a relationship between perceptual motor skills and attention, further studies with samples from other regions are necessary.

  17. Perceptual-organizational characteristics of the Rorschach task.

    Science.gov (United States)

    Smith, Steven R; Bistis, Kimberly; Zahka, Nicole E; Blais, Mark A

    2007-09-01

    The present study was designed to begin to explore the perceptual and visuospatial organization required to respond to the Rorschach task. Previous research has shown a relative independence of Rorschach scores from other measures of neurocognitive functioning (e.g., Zillmer & Perry, 1996). However, many of the neuropsychological measures used in previous studies did not require the patient to organize a complex visuospatial stimulus in the same way that the Rorschach does. In this study, data from 27 children and adolescents administered the Rorschach and the Rey-Osterreith Complex Figure Test (ROCF) were examined. Results of analyses indicated that, accounting for age and Full Scale IQ, there were a number of significant relationships between accuracy of ROCF renditions and Rorschach measures of developmental quality and perceptual accuracy. Implications for the understanding the nature of the Rorschach response process and its utility in clinical neuropsychology are discussed.

  18. Interdisciplinary Adventures in Perceptual Ecology

    Science.gov (United States)

    Bocast, Christopher S.

    A portfolio dissertation that began as acoustic ecology and matured into perceptual ecology, centered on ecomusicology, bioacoustics, and translational audio-based media works with environmental perspectives. The place of music in Western eco-cosmology through time provides a basis for structuring an environmental history of human sound perception. That history suggests that music may stabilize human mental activity, and that an increased musical practice may be essential for the human project. An overview of recent antecedents preceding the emergence of acoustic ecology reveals structural foundations from 20th century culture that underpin modern sound studies. The contextual role that Aldo Leopold, Jacob von Uexkull, John Cage, Marshall McLuhan, and others played in anticipating the development of acoustic ecology as an interdiscipline is detailed. This interdisciplinary aspect of acoustic ecology is defined and defended, while new developments like soundscape ecology are addressed, though ultimately sound studies will need to embrace a broader concept of full-spectrum "sensory" or "perceptual" ecology. The bioacoustic fieldwork done on spawning sturgeon emphasized this necessity. That study yielded scientific recordings and spectrographic analyses of spawning sounds produced by lake sturgeon, Acipenser fulvescens, during reproduction in natural habitats in the Lake Winnebago watershed in Wisconsin. Recordings were made on the Wolf and Embarrass River during the 2011-2013 spawning seasons. Several specimens were dissected to investigate possible sound production mechanisms; no sonic musculature was found. Drumming sounds, ranging from 5 to 7 Hz fundamental frequency, verified the infrasonic nature of previously undocumented "sturgeon thunder". Other characteristic noises of sturgeon spawning including low-frequency rumbles and hydrodynamic sounds were identified. Intriguingly, high-frequency signals resembling electric organ discharges were discovered. These

  19. Perceptual reasoning in adaptive fusion processing

    Science.gov (United States)

    Kadar, Ivan

    2002-07-01

    The author previously published a unified perceptual reasoning system framework for adaptive sensor fusion and situation assessment. Ths framework is re-examined to highlight the role of human perceptual reasoning and to establish the relationship between human perceptual reasoning and the Joint Director of Laboratories (JDL) fusion levels. Mappings between the fusion levels and the elements of perceptual reasoning are defined. Methods to populate the knowledge bases associated with each component of the perceptual reasoning system are highlighted. The concept and application of perception, the resultant system architecture and its candidate renditions using distributed interacting software agents (ISA) are discussed. The perceptual reasoning system is shown to be a natural governing mechanism for extracting, associating and fusing information from multiple sources while adaptively controlling the fusion level processes for optimum fusion performance. The unified modular system construct is shown to provide a formal framework to accommodate various implementation alternatives. The application of this architectural concept is illustrated for distributed fusion systems architectures and is sued to illustrate the benefits of the adaptive perceptual reasoning system concept.

  20. Perceptual centering of body segment orientation.

    Science.gov (United States)

    Hanes, Douglas A

    2007-01-01

    It has been shown experimentally that under certain combinations of sensory stimuli, human subjects can perceive one of several distinct illusions about their overall orientation in or movement through space. In at least some cases, the structure of such multistable illusory perceptions of orientation can be efficiently described by perceptual transformations that act on a current orientation estimate to yield an updated perceptual construct. Repeated application of identified generating transformations yields a limited set of predicted illusions for a given sensory environment. This approach is especially valuable for perceptual data that exhibits discretely differing classes of illusions between subjects or trials. In a previous study, application of a semigroup of perceptual centering transformations has succeeded in reproducing and simplifying data from an experiment in which subjects experiencing visual vection reported a range of illusions about the orientations of their gaze, head, and torso to gravity. After reviewing previously obtained results on perceptual centering, this article generalizes the approach, presenting the mathematics required to characterize perceptual transformations. The developed framework should be widely applicable in the understanding of perceptual illusions, particularly when these are guided by alignment with preferred constructs. Secondly, the article reveals the nontrivial mathematical process of perceptual semigroup formation and evaluation, deducing the complete description of the semigroup constructed in the previous study. Perceptual centering transformations identified in terrestrial experiments may predict illusions to be expected in spaceflight. For example, our results indicate that under certain conditions, many astronauts will misperceive a visual rotation axis to be centered in front of the head or even the torso.

  1. Acquisition versus consolidation of auditory perceptual learning using mixed-training regimens.

    Science.gov (United States)

    Maidment, David W; Kang, HiJee; Gill, Emma C; Amitay, Sygal

    2015-01-01

    Learning is considered to consist of two distinct phases-acquisition and consolidation. Acquisition can be disrupted when short periods of training on more than one task are interleaved, whereas consolidation can be disrupted when a second task is trained after the first has been initiated. Here we investigated the conditions governing the disruption to acquisition and consolidation during mixed-training regimens in which primary and secondary amplitude modulation tasks were either interleaved or presented consecutively. The secondary task differed from the primary task in either task-irrelevant (carrier frequency) or task-relevant (modulation rate) stimulus features while requiring the same perceptual judgment (amplitude modulation depth discrimination), or shared both irrelevant and relevant features but required a different judgment (amplitude modulation rate discrimination). Based on previous literature we predicted that acquisition would be disrupted by varying the task-relevant stimulus feature during training (stimulus interference), and that consolidation would be disrupted by varying the perceptual judgment required (task interference). We found that varying the task-relevant or -irrelevant stimulus features failed to disrupt acquisition but did disrupt consolidation, whereas mixing two tasks requiring a different perceptual judgment but sharing the same stimulus features disrupted both acquisition and consolidation. Thus, a distinction between acquisition and consolidation phases of perceptual learning cannot simply be attributed to (task-relevant) stimulus versus task interference. We propose instead that disruption occurs during acquisition when mixing two tasks requiring a perceptual judgment based on different cues, whereas consolidation is always disrupted regardless of whether different stimulus features or tasks are mixed. The current study not only provides a novel insight into the underlying mechanisms of perceptual learning, but also has

  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. The cerebellum and visual perceptual learning: evidence from a motion extrapolation task.

    Science.gov (United States)

    Deluca, Cristina; Golzar, Ashkan; Santandrea, Elisa; Lo Gerfo, Emanuele; Eštočinová, Jana; Moretto, Giuseppe; Fiaschi, Antonio; Panzeri, Marta; Mariotti, Caterina; Tinazzi, Michele; Chelazzi, Leonardo

    2014-09-01

    Visual perceptual learning is widely assumed to reflect plastic changes occurring along the cerebro-cortical visual pathways, including at the earliest stages of processing, though increasing evidence indicates that higher-level brain areas are also involved. Here we addressed the possibility that the cerebellum plays an important role in visual perceptual learning. Within the realm of motor control, the cerebellum supports learning of new skills and recalibration of motor commands when movement execution is consistently perturbed (adaptation). Growing evidence indicates that the cerebellum is also involved in cognition and mediates forms of cognitive learning. Therefore, the obvious question arises whether the cerebellum might play a similar role in learning and adaptation within the perceptual domain. We explored a possible deficit in visual perceptual learning (and adaptation) in patients with cerebellar damage using variants of a novel motion extrapolation, psychophysical paradigm. Compared to their age- and gender-matched controls, patients with focal damage to the posterior (but not the anterior) cerebellum showed strongly diminished learning, in terms of both rate and amount of improvement over time. Consistent with a double-dissociation pattern, patients with focal damage to the anterior cerebellum instead showed more severe clinical motor deficits, indicative of a distinct role of the anterior cerebellum in the motor domain. The collected evidence demonstrates that a pure form of slow-incremental visual perceptual learning is crucially dependent on the intact cerebellum, bearing the notion that the human cerebellum acts as a learning device for motor, cognitive and perceptual functions. We interpret the deficit in terms of an inability to fine-tune predictive models of the incoming flow of visual perceptual input over time. Moreover, our results suggest a strong dissociation between the role of different portions of the cerebellum in motor versus

  5. 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.

  6. Age-related reorganization of functional networks for successful conflict resolution: a combined functional and structural MRI study.

    Science.gov (United States)

    Schulte, Tilman; Müller-Oehring, Eva M; Chanraud, Sandra; Rosenbloom, Margaret J; Pfefferbaum, Adolf; Sullivan, Edith V

    2011-11-01

    Aging has readily observable effects on the ability to resolve conflict between competing stimulus attributes that are likely related to selective structural and functional brain changes. To identify age-related differences in neural circuits subserving conflict processing, we combined structural and functional MRI and a Stroop Match-to-Sample task involving perceptual cueing and repetition to modulate resources in healthy young and older adults. In our Stroop Match-to-Sample task, older adults handled conflict by activating a frontoparietal attention system more than young adults and engaged a visuomotor network more than young adults when processing repetitive conflict and when processing conflict following valid perceptual cueing. By contrast, young adults activated frontal regions more than older adults when processing conflict with perceptual cueing. These differential activation patterns were not correlated with regional gray matter volume despite smaller volumes in older than young adults. Given comparable performance in speed and accuracy of responding between both groups, these data suggest that successful aging is associated with functional reorganization of neural systems to accommodate functionally increasing task demands on perceptual and attentional operations.

  7. 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…

  8. Studying real-world perceptual expertise.

    Science.gov (United States)

    Shen, Jianhong; Mack, Michael L; Palmeri, Thomas J

    2014-01-01

    Significant insights into visual cognition have come from studying real-world perceptual expertise. Many have previously reviewed empirical findings and theoretical developments from this work. Here we instead provide a brief perspective on approaches, considerations, and challenges to studying real-world perceptual expertise. We discuss factors like choosing to use real-world versus artificial object domains of expertise, selecting a target domain of real-world perceptual expertise, recruiting experts, evaluating their level of expertise, and experimentally testing experts in the lab and online. Throughout our perspective, we highlight expert birding (also called birdwatching) as an example, as it has been used as a target domain for over two decades in the perceptual expertise literature.

  9. Perceptual incongruence influences bistability and cortical activation.

    Directory of Open Access Journals (Sweden)

    Gijs Joost Brouwer

    Full Text Available We employed a parametric psychophysical design in combination with functional imaging to examine the influence of metric changes in perceptual incongruence on perceptual alternation rates and cortical responses. Subjects viewed a bistable stimulus defined by incongruent depth cues; bistability resulted from incongruence between binocular disparity and monocular perspective cues that specify different slants (slant rivalry. Psychophysical results revealed that perceptual alternation rates were positively correlated with the degree of perceived incongruence. Functional imaging revealed systematic increases in activity that paralleled the psychophysical results within anterior intraparietal sulcus, prior to the onset of perceptual alternations. We suggest that this cortical activity predicts the frequency of subsequent alternations, implying a putative causal role for these areas in initiating bistable perception. In contrast, areas implicated in form and depth processing (LOC and V3A were sensitive to the degree of slant, but failed to show increases in activity when these cues were in conflict.

  10. Prior expectations facilitate metacognition for perceptual decision.

    Science.gov (United States)

    Sherman, M T; Seth, A K; Barrett, A B; Kanai, R

    2015-09-01

    The influential framework of 'predictive processing' suggests that prior probabilistic expectations influence, or even constitute, perceptual contents. This notion is evidenced by the facilitation of low-level perceptual processing by expectations. However, whether expectations can facilitate high-level components of perception remains unclear. We addressed this question by considering the influence of expectations on perceptual metacognition. To isolate the effects of expectation from those of attention we used a novel factorial design: expectation was manipulated by changing the probability that a Gabor target would be presented; attention was manipulated by instructing participants to perform or ignore a concurrent visual search task. We found that, independently of attention, metacognition improved when yes/no responses were congruent with expectations of target presence/absence. Results were modeled under a novel Bayesian signal detection theoretic framework which integrates bottom-up signal propagation with top-down influences, to provide a unified description of the mechanisms underlying perceptual decision and metacognition.

  11. Fostering Perceptual Skills in Medical Diagnosis

    NARCIS (Netherlands)

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

    2010-01-01

    Jarodzka, H., Balslev, T., Holmqvist, K., Nyström, M., Scheiter, K., Gerjets, P., & Eika, B. (2010, August). Fostering perceptual skills in medical diagnosis. Meeting of the EARLI SIG2 Text and Graphics Comprehension. Tübingen.

  12. 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.

  13. Perceptual and performance biases in action selection

    OpenAIRE

    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 effects of perceptual biases can be modified by performance factors, such as a limb's end-state-comfort (ESC; Rosenbaum et al. 1990). We investigated how two other potential performance biases affected i...

  14. Effect of practice on perceptual load

    OpenAIRE

    Mejia-Ramirez, Manuel

    2013-01-01

    Within attention studies, Lavie's load theory (Lavie & Tsal, 1994; Lavie, Hirst, de Fockert, & Viding, 2004) presented an account that could settle the question whether attention selects stimuli to be processed at an early or late stage of cognitive processing. This theory relied on the concepts of "perceptual load" and "attentional capacity", proposing that attentional resources are automatically allocated to stimuli, but when the perceptual load of the stimuli exceeds person's capacity, tas...

  15. Perceptual Integration on the Rorschach as an Indicator of Cognitive Capacity: A Developmental Study of Racial Differences in a Clinic Population

    Science.gov (United States)

    Gerstein, Alvin I.; And Others

    1976-01-01

    Rorschach protocols of both black and white children from 7 to 14 years of age, who had been evaluated at a child guidance clinic, were rescored with respect to developmental level of perceptual integration. It was found that black children had higher perceptual-integration scores in comparison to their white counterparts. (Author)

  16. Stereotype threat prevents perceptual learning.

    Science.gov (United States)

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

    2010-08-10

    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 as an increasing rate of search for a target Chinese character in a display of such characters. Displays contained two or four characters and half of these contained a target. Search rate increased across a session of training for a control group of women, but not women under ST. Speeding of search is typically explained in terms of learned "popout" (automatic attraction of attention to a target). Did women under ST learn popout but fail to express it? Following training, the women were shown two colored squares and asked to choose the one with the greater color saturation. Superimposed on the squares were task-irrelevant Chinese characters. For women not trained under ST, the presence of a trained target on one square slowed responding, indicating that training had caused the learning of an attention response to targets. Women trained under ST showed no slowing, indicating that they had not learned such an attention response.

  17. Perceptual qualities and material classes.

    Science.gov (United States)

    Fleming, Roland W; Wiebel, Christiane; Gegenfurtner, Karl

    2013-07-11

    Under typical viewing conditions, we can easily group materials into distinct classes (e.g., woods, plastics, textiles). Additionally, we can also make many other judgments about material properties (e.g., hardness, rigidity, colorfulness). Although these two types of judgment (classification and inferring material properties) have different requirements, they likely facilitate one another. We conducted two experiments to investigate the interactions between material classification and judgments of material qualities in both the visual and semantic domains. In Experiment 1, nine students viewed 130 images of materials from 10 different classes. For each image, they rated nine subjective properties (glossiness, transparency, colorfulness, roughness, hardness, coldness, fragility, naturalness, prettiness). In Experiment 2, 65 subjects were given the verbal names of six material classes, which they rated in terms of 42 adjectives describing material qualities. In both experiments, there was notable agreement between subjects, and a relatively small number of factors (weighted combinations of different qualities) were substantially independent of one another. Despite the difficulty of classifying materials from images (Liu, Sharan, Adelson, & Rosenholtz, 2010), the different classes were well clustered in the feature space defined by the subjective ratings. K-means clustering could correctly identify class membership for over 90% of the samples, based on the average ratings across subjects. We also found a high degree of consistency between the two tasks, suggesting subjects access similar information about materials whether judging their qualities visually or from memory. Together, these findings show that perceptual qualities are well defined, distinct, and systematically related to material class membership.

  18. Attributing illness to food

    DEFF Research Database (Denmark)

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

    2005-01-01

    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...... 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 component...

  19. Perceptual effects of bolus size

    NARCIS (Netherlands)

    Prinz, J.F.; Wijk, de R.A.

    2007-01-01

    A trained panel of 19 subjects were asked to rate a number of sensory attributes of commercially available vanilla custard desserts. Stimuli were placed in plastic cups and were sampled using 11-mm-diameter straws. In total, 304 samples were weighed before and after sampling and the volume ingested

  20. Perceptual Learning of Interrupted Speech

    NARCIS (Netherlands)

    Benard, Michel Ruben; Başkent, Deniz

    2013-01-01

    The intelligibility of periodically interrupted speech improves once the silent gaps are filled with noise bursts. This improvement has been attributed to phonemic restoration, a top-down repair mechanism that helps intelligibility of degraded speech in daily life. Two hypotheses were investigated u

  1. Dichotomy and perceptual distortions in absolute pitch ability

    OpenAIRE

    Athos, E. Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane

    2007-01-01

    Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved...

  2. The effect of variation in naturalness on phonetic perceptual identification

    Science.gov (United States)

    Remez, Robert E.; Yang, Cynthia Y.; Piorkowski, Rebecca L.; Wissig, Stephanie; Batchelder, Abigail; Nam, Heddy

    2002-05-01

    The relation between apparent naturalness and phonetic identification was assessed in six perceptual tests. A seven-step place-of-articulation series spanning [da] to [ga] was created with speech synthesis approximating the spectra of natural samples. The sensitivity of perceivers to this realization of a place contrast was assessed by estimating the cumulative d' across the series in identification tests. Four variants of this series differing in apparent naturalness were produced by altering the synthesis source function while preserving the center frequency and bandwidth of the formants, and by replicating the gross spectrotemporal patterns with time-varying sinusoids. In addition to calibrating perceivers' sensitivity to the place contrast over variation in naturalness, we conducted a naturalness tournament composed of items drawn from the five test series. A correlation of the findings of the naturalness tournament with the measures of phonetic sensitivity offers an index of the effect of variation in naturalness on phonetic perception. This study can resolve the dispute between the classic premise that intelligibility and naturalness are orthogonal attributes of speech perception, and the more recent premise entailed by episodically based accounts of perceptual categorization, that novel instances are identified by virtue of auditory similarity to prior exemplars. [Research supported by NIDCD.

  3. Ravens attribute visual access to unseen competitors.

    Science.gov (United States)

    Bugnyar, Thomas; Reber, Stephan A; Buckner, Cameron

    2016-02-02

    Recent studies purported to demonstrate that chimpanzees, monkeys and corvids possess a basic Theory of Mind, the ability to attribute mental states like seeing to others. However, these studies remain controversial because they share a common confound: the conspecific's line of gaze, which could serve as an associative cue. Here, we show that ravens Corvus corax take into account the visual access of others, even when they cannot see a conspecific. Specifically, we find that ravens guard their caches against discovery in response to the sounds of conspecifics when a peephole is open but not when it is closed. Our results suggest that ravens can generalize from their own perceptual experience to infer the possibility of being seen. These findings confirm and unite previous work, providing strong evidence that ravens are more than mere behaviour-readers.

  4. 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...

  5. Consequences of comorbidity of developmental coordination disorders and learning disabilities for severity and pattern of perceptual-motor dysfunction

    OpenAIRE

    2003-01-01

    Children with developmental coordination disorder (DCD) have difficulty learning and performing age-appropriate perceptual-motor skills in the absence of diagnosable neurological disorders. Descriptive studies have shown that comorbidity of DCD exists with attention-deficit/hyperactivity disorder (ADHD) and learning disabilities (LD). This study examined the consequences of the comorbidity of DCD and LD for the severity and pattern of perceptual-motor dysfunction. Compared to children with DC...

  6. 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…

  7. 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.

  8. 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.

  9. Perceptual continuation and depth in visual phantoms can be explained by perceptual transparency.

    Science.gov (United States)

    Kitaoka, A; Gyoba, J; Kawabata, H; Sakurai, K

    2001-01-01

    We try to explain perceptual continuation and depth in the visual-phantom illusion in terms of perceptual transparency. Perceptual continuation of inducing gratings across the occluder in stationary phantoms could be explained with unique transparency, a notion proposed by Anderson (1997 Perception 26 419-453). This view is consistent with a number of previous reports including that of McCourt (1994 Vision Research 34 1609-1617) who criticized the stationary phantom illusion from the viewpoint of his counterphase lightness induction or grating induction, which might involve invalid transparency. Here we confirm that the photopic phantom illusion (Kitaoka et al, 1999 Perception 28 825-834) really gives in-phase lightness induction and involves bistable transparency. It is thus suggested that perceptual continuation and depth in the visual-phantom illusion depend on perceptual transparency.

  10. 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

  11. Zooming in on the cause of the perceptual load effect in the go/no-go paradigm.

    Science.gov (United States)

    Chen, Zhe; Cave, Kyle R

    2016-08-01

    Perceptual load theory (Lavie, 2005) claims that attentional capacity that is not used for the current task is allocated to irrelevant distractors. It predicts that if the attentional demands of the current task are high, distractor interference will be low. One particularly powerful demonstration of perceptual load effects on distractor processing relies on a go/no-go cue that is interpreted by either simple feature detection or feature conjunction (Lavie, 1995). However, a possible alternative interpretation of these effects is that the differential degree of distractor processing is caused by how broadly attention is allocated (attentional zoom) rather than to perceptual load. In 4 experiments, we show that when stimuli are arranged to equalize the extent of spatial attention across conditions, distractor interference varies little whether cues are defined by a simple feature or a conjunction, and that the typical perceptual load effect emerges only when attentional zoom can covary with perceptual load. These results suggest that attentional zoom can account for the differential degree of distractor processing traditionally attributed to perceptual load in the go/no-go paradigm. They also provide new insight into how different factors interact to control distractor interference. (PsycINFO Database Record

  12. 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)

  13. Perceptual Contrast Enhancement with Dynamic Range Adjustment

    Science.gov (United States)

    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 problem with the HVS. To pre-condition the input image before the HE procedure is implemented, a perceptual contrast map (PCM) is constructed based on the modified Difference of Gaussian (DOG) algorithm. As a result, the contrast of the image is sharpened and high frequency noise is suppressed. A modified Clipped Histogram Equalization (CHE) is also developed which improves visual quality by automatically detecting the dynamic range of the image with improved perceptual contrast. Experimental results show that the new HE algorithm outperforms several state-of-the-art algorithms in improving perceptual contrast and enhancing details. In addition, the new algorithm is simple to implement, making it suitable for real-time applications. PMID:24339452

  14. Retention of perceptual generalization of fear extinction.

    Science.gov (United States)

    Pappens, Meike; Schroijen, Mathias; Van den Bergh, Omer; Van Diest, Ilse

    2015-12-01

    Fear reduction obtained during a fear extinction procedure can generalize from the extinction stimulus to other perceptually similar stimuli. Perceptual generalization of fear extinction typically follows a perceptual gradient, with increasing levels of fear reduction the more a stimulus resembles the extinction stimulus. The current study aimed to investigate whether perceptual generalization of fear extinction can be observed also after a retention interval of 24h. Fear was acquired to three geometrical figures of different sizes (CS(+), CS1(+) and CS2(+)) by consistently pairing them with a short-lasting suffocation experience (US). Three other geometrical figures that were never followed by the US served as control stimuli (CS(-), CS1(-), CS2(-)). Next, only the CS(+) was extinguished by presenting it in the absence of the US. One day later, fear responses to all stimuli were assessed without any US-presentation. Outcome measures included startle blink EMG, skin conductance, US expectancy, respiratory rate and tidal volume. On day 2 spontaneous recovery of fear was observed in US expectancy and tidal volume, but not in the other outcomes. Evidence for the retention of fear extinction generalization was present in US expectancy and skin conductance, but a perceptual gradient in the retention of generalized fear extinction could not be observed.

  15. Multisensory perceptual learning and sensory substitution.

    Science.gov (United States)

    Proulx, Michael J; Brown, David J; Pasqualotto, Achille; Meijer, Peter

    2014-04-01

    One of the most exciting recent findings in neuroscience has been the capacity for neural plasticity in adult humans and animals. Studies of perceptual learning have provided key insights into the mechanisms of neural plasticity and the changes in functional neuroanatomy that it affords. Key questions in this field of research concern how practice of a task leads to specific or general improvement. Although much of this work has been carried out with a focus on a single sensory modality, primarily visual, there is increasing interest in multisensory perceptual learning. Here we will examine how advances in perceptual learning research both inform and can be informed by the development and advancement of sensory substitution devices for blind persons. To allow 'sight' to occur in the absence of visual input through the eyes, visual information can be transformed by a sensory substitution device into a representation that can be processed as sound or touch, and thus give one the potential to 'see' through the ears or tongue. Investigations of auditory, visual and multisensory perceptual learning can have key benefits for the advancement of sensory substitution, and the study of sensory deprivation and sensory substitution likewise will further the understanding of perceptual learning in general and the reverse hierarchy theory in particular. It also has significant importance for the developing understanding of the brain in metamodal terms, where functional brain areas might be best defined by the computations they carry out rather than by their sensory-specific processing role.

  16. Adapting Choral Singing Experiences for Older Adults: The Implications of Sensory, Perceptual, and Cognitive Changes

    Science.gov (United States)

    Yinger, Olivia Swedberg

    2014-01-01

    As people age, they naturally experience sensory, perceptual, and cognitive changes. Many of these changes necessitate adaptations in designing programs for older adults. Choral singing is an activity that has many potential benefits for older adults, yet the rehearsal environment, presentation style, and content of material presented may need to…

  17. The development of race‐based perceptual categorization: skin color dominates early category judgments

    NARCIS (Netherlands)

    Dunham, Yarrow; Stepanova, Elena V.; Dotsch, Ron; Todorov, Alexander

    2014-01-01

    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, ). However, such work has rarely separated the influence of skin color from other physiognomic features considered by adul

  18. Intra and Intersensory Haptic Perception: Their Spatial and Perceptual-Motor Correlates.

    Science.gov (United States)

    Derevensky, Jeffrey L.; Petrushka, Tima L.

    This study investigated the relationship between intramodal and intermodal information processing and performance on traditional age appropriate tests of spatial and perceptual-motor abilities. The ability of 65 normal kindergarten, first grade and second grade children to match to either a tactile or a visual standard was assessed with a modified…

  19. 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.

  20. On Macroscopic Complexity and Perceptual Coding

    CERN Document Server

    Scoville, John

    2010-01-01

    While Shannon information establishes limits to the universal data compression of binary data, no existing theory provides an equivalent characterization of the lossy data compression algorithms prevalent in audiovisual media. The current paper proposes a mathematical framework for perceptual coding and inference which quantifies the complexity of objects indistinguishable to a particular observer. A definition of the complexity is presented and related to a generalization of Boltzmann entropy for these equivalence classes. When the classes are partitions of phase space, corresponding to classical observations, this is the proper Boltzmann entropy and the macroscopic complexity agrees with the Algorithmic Entropy. For general classes, the macroscopic complexity measure determines the optimal lossy compression of the data. Conversely, perceptual coding algorithms may be used to construct upper bounds on certain macroscopic complexities. Knowledge of these complexities, in turn, allows perceptual inference whic...

  1. Perceptual Templates Improvement through Action Video Game Playing and Comparison to Perceptual Learning

    Directory of Open Access Journals (Sweden)

    Ruyuan Zhang

    2011-05-01

    Full Text Available Action video game playing substantially improves visual performance; however, the source of this improvement remains unclear. Here we use the equivalent external noise technique to characterize the mechanism by which action video games may facilitate performance (Lu & Dosher, 1998. In first study, Action Video Game Players (VGPs and Non-Action Video Game Players (NVGPs performed a foveal orientation identification task at different external noise levels. VGPs showed lower thresholds than NVGPs with a marked difference at different noise levels. Perceptual Template Model fitting indicated that there were an 11% additive noise reduction and a 25% external noise exclusion. The causal effect of action video game playing was confirmed in a following 50 hour training study, This work establishes that playing action video games leads to robust internal addictive and external noise exclusion, consistent with the use of better matched perceptual templates. To investigate the discrepancy between our results and previous fovea perceptual learning research (Lu et al, 2004, same stimuli in previous experiment were used in perceptual learning experiment and we find same perceptual template improvement pattern. This suggest both action video game playing and perceptual learning could lead to better perceptual template.

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

    Science.gov (United States)

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

    2014-01-01

    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 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

  3. 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.

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

    Science.gov (United States)

    Kang, Ramanjot; Sarro, Emma C; Sanes, Dan H

    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 asked whether a brief period of training during development could compensate for the perceptual deficits displayed by adult animals reared with CHL. Juvenile gerbils with CHL, and age-matched controls, were trained on a frequency modulation (FM) detection task for 4 or 10 days. The performance of each group was subsequently assessed in adulthood, and compared to adults with normal hearing (NH) or adults raised with CHL that did not receive juvenile training. We show that as juveniles, both CHL and NH animals display similar FM detection thresholds that are not immediately impacted by the perceptual training. However, as adults, detection thresholds and psychometric function slopes of these animals were significantly improved. Importantly, CHL adults with juvenile training displayed thresholds that approached NH adults. Additionally, we found that hearing impaired animals trained for 10 days displayed adult thresholds closer to untrained adults than those trained for 4 days. Thus, a relatively brief period of auditory training may compensate for the deleterious impact of hearing deprivation on auditory perception on the trained task.

  5. Perceptual transparency in neon color spreading displays.

    Science.gov (United States)

    Ekroll, Vebjørn; Faul, Franz

    2002-08-01

    In neon color spreading displays, both a color illusion and perceptual transparency can be seen. In this study, we investigated the color conditions for the perception of transparency in such displays. It was found that the data are very well accounted for by a generalization of Metelli's (1970) episcotister model of balanced perceptual transparency to tristimulus values. This additive model correctly predicted which combinations of colors would lead to optimal impressions of transparency. Color combinations deviating slightly from the additive model also looked transparent, but less convincingly so.

  6. A perceptual account of symbolic reasoning

    Directory of Open Access Journals (Sweden)

    David eLandy

    2014-04-01

    Full Text Available People can be taught to manipulate symbols according to formal mathematical and logical rules. Cognitive scientists have traditionally viewed this capacity—the capacity for symbolic reasoning—as grounded in the ability to internally represent numbers, logical relationships, and mathematical rules in an abstract, amodal fashion. We present an alternative view, portraying symbolic reasoning as a special kind of embodied reasoning in which arithmetic and logical formulae, externally represented as notations, serve as targets for powerful perceptual and sensorimotor systems. Although symbolic reasoning often conforms to abstract mathematical principles, it is typically implemented by perceptual and sensorimotor engagement with concrete environmental structures.

  7. Security analysis of robust perceptual hashing

    Science.gov (United States)

    Koval, Oleksiy; Voloshynovskiy, Sviatoslav; Beekhof, Fokko; Pun, Thierry

    2008-02-01

    In this paper we considered the problem of security analysis of robust perceptual hashing in authentication application. The main goal of our analysis was to estimate the amount of trial efforts of the attacker, who is acting within the Kerckhoffs security principle, to reveal a secret key. For this purpose, we proposed to use Shannon equivocation that provides an estimate of complexity of the key search performed based on all available prior information and presented its application to security evaluation of particular robust perceptual hashing algorithms.

  8. A perceptual account of symbolic reasoning.

    Science.gov (United States)

    Landy, David; Allen, Colin; Zednik, Carlos

    2014-01-01

    People can be taught to manipulate symbols according to formal mathematical and logical rules. Cognitive scientists have traditionally viewed this capacity-the capacity for symbolic reasoning-as grounded in the ability to internally represent numbers, logical relationships, and mathematical rules in an abstract, amodal fashion. We present an alternative view, portraying symbolic reasoning as a special kind of embodied reasoning in which arithmetic and logical formulae, externally represented as notations, serve as targets for powerful perceptual and sensorimotor systems. Although symbolic reasoning often conforms to abstract mathematical principles, it is typically implemented by perceptual and sensorimotor engagement with concrete environmental structures.

  9. 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

  10. A perceptual learning deficit in Chinese developmental dyslexia as revealed by visual texture discrimination training.

    Science.gov (United States)

    Wang, Zhengke; Cheng-Lai, Alice; Song, Yan; Cutting, Laurie; Jiang, Yuzheng; Lin, Ou; Meng, Xiangzhi; Zhou, Xiaolin

    2014-08-01

    Learning to read involves discriminating between different written forms and establishing connections with phonology and semantics. This process may be partially built upon visual perceptual learning, during which the ability to process the attributes of visual stimuli progressively improves with practice. The present study investigated to what extent Chinese children with developmental dyslexia have deficits in perceptual learning by using a texture discrimination task, in which participants were asked to discriminate the orientation of target bars. Experiment l demonstrated that, when all of the participants started with the same initial stimulus-to-mask onset asynchrony (SOA) at 300 ms, the threshold SOA, adjusted according to response accuracy for reaching 80% accuracy, did not show a decrement over 5 days of training for children with dyslexia, whereas this threshold SOA steadily decreased over the training for the control group. Experiment 2 used an adaptive procedure to determine the threshold SOA for each participant during training. Results showed that both the group of dyslexia and the control group attained perceptual learning over the sessions in 5 days, although the threshold SOAs were significantly higher for the group of dyslexia than for the control group; moreover, over individual participants, the threshold SOA negatively correlated with their performance in Chinese character recognition. These findings suggest that deficits in visual perceptual processing and learning might, in part, underpin difficulty in reading Chinese.

  11. Atypical prosody in Asperger syndrome: perceptual and acoustic measurements.

    Science.gov (United States)

    Filipe, Marisa G; Frota, Sónia; Castro, São Luís; Vicente, Selene G

    2014-08-01

    It is known that individuals with Asperger syndrome (AS) may show no problems with regard to what is said (e.g., lexical content) but tend to have difficulties in how utterances are produced, i.e., they may show prosodic impairments. In the present study, we focus on the use of prosodic features to express grammatical meaning. Specifically, we explored the sentence type difference between statements and questions that is conveyed by intonation, using perceptual and acoustic measurements. Children aged 8 and 9 years with AS (n = 12) were matched according to age and nonverbal intelligence with typically developing peers (n = 17). Although children with AS could produce categorically accurate prosodic patterns, their prosodic contours were perceived as odd by adult listeners, and acoustic measurements showed alterations in duration and pitch. Additionally, children with AS had greater variability in fundamental frequency contours compared to typically developing peers.

  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. 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...

  14. Adaptation and perceptual norms in color vision.

    Science.gov (United States)

    Webster, Michael A; Leonard, Deanne

    2008-11-01

    Many perceptual dimensions are thought to be represented relative to an average value or norm. Models of norm-based coding assume that the norm appears psychologically neutral because it reflects a neutral response in the underlying neural code. We tested this assumption in human color vision by asking how judgments of "white" are affected as neural responses are altered by adaptation. The adapting color was varied to determine the stimulus level that did not bias the observer's subjective white point. This level represents a response norm at the stages at which sensitivity is regulated by the adaptation, and we show that these response norms correspond to the perceptually neutral stimulus and that they can account for how the perception of white varies both across different observers and within the same observer at different locations in the visual field. We also show that individual differences in perceived white are reduced when observers are exposed to a common white adapting stimulus, suggesting that the perceptual differences are due in part to differences in how neural responses are normalized. These results suggest a close link between the norms for appearance and coding in color vision and illustrate a general paradigm for exploring this link in other perceptual domains.

  15. Modelling the Perceptual Components of Loudspeaker Distortion

    DEFF Research Database (Denmark)

    Olsen, Sune L.; Agerkvist, Finn T.; MacDonald, Ewen;

    2016-01-01

    While non-linear distortion in loudspeakers decreases audio quality, the perceptual consequences can vary substantially. This paper investigates the metric Rnonlin [1] which was developed to predict subjective measurements of sound quality in nonlinear systems. The generalisability of the metric...

  16. 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 a...

  17. 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

  18. Perceptual effects of overlapping curved glass

    NARCIS (Netherlands)

    Cruz, P.J.S.; Veer, F.A.; Carvalho, P.L.L.

    2010-01-01

    The application of glass in contemporary architecture explores perceptual phenomenon that intentionally change the way we experience space. SANAA'S recent work uses glass in a radical way, proposing a renewed approach to transparency. The Toledo Glass Pavilion, with most spaces defined by glass wall

  19. Perceptual and performance biases in action selection

    NARCIS (Netherlands)

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

    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

  20. Fostering perceptual skills in medical diagnosis

    NARCIS (Netherlands)

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

    2010-01-01

    Jarodzka, H., Balslev, T., Holmqvist, K., Nyström, M., Scheiter, K., Gerjets, P., & Eika, B. (2010, August). Fostering perceptual skills in medical diagnosis. Meeting of the EARLI SIG6/7 Instructional Design and Learning and Instruction with Computers, Ulm, Germany.

  1. Improving Perceptual Skills with 3-Dimensional Animations.

    Science.gov (United States)

    Johns, Janet Faye; Brander, Julianne Marie

    1998-01-01

    Describes three-dimensional computer aided design (CAD) models for every component in a representative mechanical system; the CAD models made it easy to generate 3-D animations that are ideal for teaching perceptual skills in multimedia computer-based technical training. Fifteen illustrations are provided. (AEF)

  2. Perceptual Load Influences Selective Attention across Development

    Science.gov (United States)

    Couperus, Jane W.

    2011-01-01

    Research suggests that visual selective attention develops across childhood. However, there is relatively little understanding of the neurological changes that accompany this development, particularly in the context of adult theories of selective attention, such as N. Lavie's (1995) perceptual load theory of attention. This study examined visual…

  3. 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.

  4. Perceptual transparency in 3- to 4-month-old infants.

    Science.gov (United States)

    Otsuka, Yumiko; Kanazawa, So; Yamaguchi, Masami K

    2006-01-01

    We examined perceptual transparency in infants. In a previous study, Johnson and Aslin (2000 Developmental Psychology 36 808 - 816) found that 4-month-olds could perceive transparency in a moving chromatic display, but not in an achromatic display. In this study, we further examined perceptual transparency in infants using a static achromatic display. Considering the development of figural organisation and contrast sensitivity, we assumed that 3- to 4-month-olds would perceive transparency even in a static achromatic display. We created a transparency and a non-transparent display composed of a partially overlapping circle and square, by switching the colours. Infants aged 3 to 4 months (n = 24) were familiarised with the transparency display (experiment 1) or with the non-transparent display (experiment 2). Then, they were confronted with a uniform colour and a two-colour figure. Infants showed novelty preference for the two-colour figure after they had been familiarised with the transparency display (experiment 1), but not after they had been familiarised with the non-transparent display (experiment 2). These results suggest that 3- to 4-month-old infants can perceive transparency in a static achromatic display.

  5. Novel Topic Authorship Attribution

    Science.gov (United States)

    2011-03-01

    cross-validation, genre shift, vector projection, singular value decomposition, principal component analysis Unclassified Unclassified Unclassified...by eight students. Each student wrote a total of 24 documents in three different genres about three different topics. They found that compensating for...Baayen, H. Halteren, A. Neijt, and F. Tweedie, “Outside the cave of shadows: Using syntactic annotation to enhance authorship attribution,” Literary

  6. 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.

  7. The perceptual domain: a taxonomy for allied health educators.

    Science.gov (United States)

    Hooker, E Z

    1981-08-01

    A taxonomy of the perceptual domain was proposed over a decade ago. It is hierarchical, as are the taxonomies in the cognitive, affective, and psychomotor domains. Perception involves extraction of information from presenting stimuli, and there is progression of information extraction as the hierarchy is ascended. Perceptual performance at the higher levels of the taxonomy assumes perceptual abilities at the lower levels. A modified version of the perceptual taxonomy applicable to allied health education is presented. Methods concerning application of the taxonomy are suggested. Use of the taxonomy of the perceptual domain would help allied health educators plan instruction and evaluate teaching.

  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. Cinematic innervation: the intuitive form of perception in the distracted perceptual field

    Directory of Open Access Journals (Sweden)

    Sungyong Ahn

    2013-09-01

    Full Text Available In “The Work of Art in the Age of Its Technological Reproducibility,” Walter Benjamin alluded that the human perceptual field in his time would become more distracted by the intervention of technologies, and so masses’ tactility activated by distraction would be more important in the mechanized perception. Regarding this historical situation, Benjamin anticipated that the new mode of mass perception would be organized through people's collective “innervation” to technologies. This article aims to contextualize this physiological term's cultural, technical, and political implications within various discourses about perception from the late 19th century physiologies to early 20th century film theories. Benjamin considers the tactility of people's potential to reconstruct the optical scheme of perception from the “flatness of screen” in which distances between viewers and perceived objects collapse. In a similar vein, the late 19th century's physiology reconceptualized perception in its relation not so much to the transcendental division of subject/object as to the sensual condition of a retina as “a single immanent plane.” From this perspective, perception is phenomena entailed by a body's contact to a sensual environment, so how sense inputs circulate in a neural network is a determinant for explaining perceptual processes. With regard to this paradigm change, the invention of cinema in the late 19th century was significant because it radically changed the composition of the perceptual field in two directions. Cinema introduced the virtualized perceptual fields on which sense circulations were completely controlled by the operation of camera. At the same time, the mediation of projectors in theaters reorganized viewers’ neural paths for perceptual innervation. As Hugo Münsterberg and Sergei Eisenstein's theories reflect, cinematic media's intervention in the perceptual field made it possible for masses’ collective

  10. Category and perceptual learning in subjects with treated Wilson's disease.

    Directory of Open Access Journals (Sweden)

    Pengjing Xu

    Full Text Available 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 controls. The WD subjects exhibited deficits in both forms of category learning and in perceptual learning in high external noise. However, their perceptual learning in low external noise was relatively spared. There was no significant correlation between the two forms of category learning, nor between perceptual learning in low external noise and either form of category learning. Perceptual learning in high external noise was, however, significantly correlated with information-integration but not with rule-based category learning. The results suggest that there may be a strong link between information-integration category learning and perceptual learning in high external noise. Damage to brain structures that are important for information-integration category learning may lead to poor perceptual learning in high external noise, yet spare perceptual learning in low external noise. Perceptual learning in high and low external noise conditions may involve separate neural substrates.

  11. From Perceptual Categories to Concepts: What Develops?

    Science.gov (United States)

    Sloutsky, Vladimir M

    2010-09-01

    People are remarkably smart: they use language, possess complex motor skills, make non-trivial inferences, develop and use scientific theories, make laws, and adapt to complex dynamic environments. Much of this knowledge requires concepts and this paper focuses on how people acquire concepts. It is argued that conceptual development progresses from simple perceptual grouping to highly abstract scientific concepts. This proposal of conceptual development has four parts. First, it is argued that categories in the world have different structure. Second, there might be different learning systems (sub-served by different brain mechanisms) that evolved to learn categories of differing structures. Third, these systems exhibit differential maturational course, which affects how categories of different structures are learned in the course of development. And finally, an interaction of these components may result in the developmental transition from perceptual groupings to more abstract concepts. This paper reviews a large body of empirical evidence supporting this proposal.

  12. Deception in plants: mimicry or perceptual exploitation?

    Science.gov (United States)

    Schaefer, H Martin; Ruxton, Graeme D

    2009-12-01

    Mimicry involves adaptive resemblance between a mimic and a model. However, despite much recent research, it remains contentious in plants. Here, we review recent progress on studying deception by flowers, distinguishing between plants relying on mimicry to achieve pollination and those relying on the exploitation of the perceptual biases of animals. We disclose fundamental differences between both mechanisms and explain why the evolution of exploitation is less constrained than that of mimicry. Exploitation of perceptual biases might thus be a precursor for the gradual evolution of mimicry. Increasing knowledge on the sensory and cognitive filters in animals, and on the selective pressures that maintain them, should aid researchers in tracing the evolutionary dynamics of deception in plants.

  13. Zen Mountains: An Illusion of Perceptual Transparency

    Directory of Open Access Journals (Sweden)

    Susan G. Wardle

    2015-04-01

    Full Text Available The human visual system is usually very successful in segmenting complex natural scenes. During a trip to the Nepalese Himalayas, we observed an impossible example of Nature's beauty: “transparent” mountains. The scene is captured in a photograph in which a pair of mountain peaks viewed in the far distance appear to be transparent. This illusion results from a fortuitous combination of lighting and scene conditions, which induce an erroneous integration of multiple segmentation cues. The illusion unites three classic principles of visual perception: Metelli's constraints for perceptual transparency, the Gestalt principle of good continuation, and depth from contrast and atmospheric scattering. This real-world “failure” of scene segmentation reinforces how ingeniously the human visual system typically integrates complex sources of perceptual information using heuristics based on likelihood as shortcuts to veridical perception.

  14. Surprise Leads to Noisier Perceptual Decisions

    Directory of Open Access Journals (Sweden)

    Marta I Garrido

    2011-02-01

    Full Text Available Surprising events in the environment can impair task performance. This might be due to complete distraction, leading to lapses during which performance is reduced to guessing. Alternatively, unpredictability might cause a graded withdrawal of perceptual resources from the task at hand and thereby reduce sensitivity. Here we attempt to distinguish between these two mechanisms. Listeners performed a novel auditory pitch—duration discrimination, where stimulus loudness changed occasionally and incidentally to the task. Responses were slower and less accurate in the surprising condition, where loudness changed unpredictably, than in the predictable condition, where the loudness was held constant. By explicitly modelling both lapses and changes in sensitivity, we found that unpredictable changes diminished sensitivity but did not increase the rate of lapses. These findings suggest that background environmental uncertainty can disrupt goal-directed behaviour. This graded processing strategy might be adaptive in potentially threatening contexts, and reflect a flexible system for automatic allocation of perceptual resources.

  15. Neurophysiological mechanisms involved in auditory perceptual organization

    Directory of Open Access Journals (Sweden)

    Aurélie Bidet-Caulet

    2009-09-01

    Full Text Available In our complex acoustic environment, we are confronted with a mixture of sounds produced by several simultaneous sources. However, we rarely perceive these sounds as incomprehensible noise. Our brain uses perceptual organization processes to independently follow the emission of each sound source over time. If the acoustic properties exploited in these processes are well-established, the neurophysiological mechanisms involved in auditory scene analysis have raised interest only recently. Here, we review the studies investigating these mechanisms using electrophysiological recordings from the cochlear nucleus to the auditory cortex, in animals and humans. Their findings reveal that basic mechanisms such as frequency selectivity, forward suppression and multi-second habituation shape the automatic brain responses to sounds in a way that can account for several important characteristics of perceptual organization of both simultaneous and successive sounds. One challenging question remains unresolved: how are the resulting activity patterns integrated to yield the corresponding conscious perceptsµ

  16. 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.

  17. 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

  18. 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...

  19. Perceptual centering effects in body orientation.

    Science.gov (United States)

    Hanes, D A

    2006-04-01

    This study mathematically characterizes the results of DiZio and Lackner (Percept Psychphys 39(1): 39-46) on the perception of self-orientation during circular vection induced by an optokinetic stimulus. Using the hypothesis of perceptual centering, it is shown that five basic centering transformations can logically account for the full range of illusions reported by the subjects. All five of these transformations center the perceived orientations of body components, the rotating disk, and gravity : two align the perceived visual and inertial rotation axes, one centers the perceived axis of visual rotation in front of the head, and two straighten the perceived neck angle. These transformations generate a mathematical semigroup. Application of the semigroup to an actual stimulus condition generates an orbit of predicted illusions. The semigroup analysis of perceptual centering predicts all of the illusions observed in the experiments of DiZio and Lackner (Percept Psychphys 39(1): 39-46). Moreover, the structure of perceptual centering (1) provides a logical explanation for the occurrence of those misperceptions; and (2) predicts the complete set of perceptions that are expected to occur in a larger sample. In addition, our analysis predicts illusions in experimental conditions not yet investigated.

  20. Perceptual and neural olfactory similarity in honeybees.

    Directory of Open Access Journals (Sweden)

    Fernando Guerrieri

    2005-04-01

    Full Text Available The question of whether or not neural activity patterns recorded in the olfactory centres of the brain correspond to olfactory perceptual measures remains unanswered. To address this question, we studied olfaction in honeybees Apis mellifera using the olfactory conditioning of the proboscis extension response. We conditioned bees to odours and tested generalisation responses to different odours. Sixteen odours were used, which varied both in their functional group (primary and secondary alcohols, aldehydes and ketones and in their carbon-chain length (from six to nine carbons. The results obtained by presentation of a total of 16 x 16 odour pairs show that (i all odorants presented could be learned, although acquisition was lower for short-chain ketones; (ii generalisation varied depending both on the functional group and the carbon-chain length of odours trained; higher generalisation was found between long-chain than between short-chain molecules and between groups such as primary and secondary alcohols; (iii for some odour pairs, cross-generalisation between odorants was asymmetric; (iv a putative olfactory space could be defined for the honeybee with functional group and carbon-chain length as inner dimensions; (v perceptual distances in such a space correlate well with physiological distances determined from optophysiological recordings of antennal lobe activity. We conclude that functional group and carbon-chain length are inner dimensions of the honeybee olfactory space and that neural activity in the antennal lobe reflects the perceptual quality of odours.

  1. Perceptual and Neural Olfactory Similarity in Honeybees

    Directory of Open Access Journals (Sweden)

    Guerrieri Fernando

    2005-01-01

    Full Text Available The question of whether or not neural activity patterns recorded in the olfactory centres of the brain correspond to olfactory perceptual measures remains unanswered. To address this question, we studied olfaction in honeybees Apis mellifera using the olfactory conditioning of the proboscis extension response. We conditioned bees to odours and tested generalisation responses to different odours. Sixteen odours were used, which varied both in their functional group (primary and secondary alcohols, aldehydes and ketones and in their carbon-chain length (from six to nine carbons.The results obtained by presentation of a total of 16 x 16 odour pairs show that (i all odorants presented could be learned, although acquisition was lower for short-chain ketones; (ii generalisation varied depending both on the functional group and the carbon-chain length of odours trained; higher generalisation was found between long-chain than between short-chain molecules and between groups such as primary and secondary alcohols; (iii for some odour pairs, cross-generalisation between odorants was asymmetric; (iv a putative olfactory space could be defined for the honeybee with functional group and carbon-chain length as inner dimensions; (v perceptual distances in such a space correlate well with physiological distances determined from optophysiological recordings of antennal lobe activity. We conclude that functional group and carbon-chain length are inner dimensions of the honeybee olfactory space and that neural activity in the antennal lobe reflects the perceptual quality of odours.

  2. Perceptual asymmetries and handedness: A neglected link?

    Directory of Open Access Journals (Sweden)

    Daniele eMarzoli

    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.

  3. Generalized perceptual features for animal vocalization classification

    Science.gov (United States)

    Clemins, Patrick J.; Johnson, Michael T.

    2001-05-01

    Two sets of generalized, perceptual-based features are investigated for use in classifying animal vocalizations. Since many species, especially mammals, share similar physical sound perception mechanisms which vary in size, two features sets commonly used in human speech processing, mel-frequency cepstral coefficients (MFCCs) and perceptual linear prediction (PLP) analysis, are modified for use in other species. One modification made to the feature extraction process is incorporating the frequency range of hearing and length of the basilar membrane of the animal in order to correctly determine the width and location of the critical band filters used for signal processing. Experimentally determined critical bands (equivalent rectangular bandwidth) and equal loudness curves (audiograms) can also be incorporated directly into the feature extraction process. Experiments are performed on African elephant (Loxodonta africana) vocalizations using a hidden Markov model (HMM) based classifier showing increased classification accuracy when using features sets based on the specific animals perceptual abilities compared to the original human perception-based feature sets.

  4. Brightness and darkness as perceptual dimensions.

    Directory of Open Access Journals (Sweden)

    Tony Vladusich

    2007-10-01

    Full Text Available A common-sense assumption concerning visual perception states that brightness and darkness cannot coexist at a given spatial location. One corollary of this assumption is that achromatic colors, or perceived grey shades, are contained in a one-dimensional (1-D space varying from bright to dark. The results of many previous psychophysical studies suggest, by contrast, that achromatic colors are represented as points in a color space composed of two or more perceptual dimensions. The nature of these perceptual dimensions, however, presently remains unclear. Here we provide direct evidence that brightness and darkness form the dimensions of a two-dimensional (2-D achromatic color space. This color space may play a role in the representation of object surfaces viewed against natural backgrounds, which simultaneously induce both brightness and darkness signals. Our 2-D model generalizes to the chromatic dimensions of color perception, indicating that redness and greenness (blueness and yellowness also form perceptual dimensions. Collectively, these findings suggest that human color space is composed of six dimensions, rather than the conventional three.

  5. Interocular transfer of perceptual skills after sleep.

    Science.gov (United States)

    Deliens, Gaétane; Schmitz, Rémy; Peigneux, Philippe

    2014-01-24

    Several studies suggest that sleep improves perceptual skills in the visual texture discrimination task (TDT). Here we report that besides consolidation, sleep also generalizes the learned perceptual abilities to the untrained eye. Healthy volunteers (n = 32) were trained on the TDT, in which they had to discriminate between horizontal and vertical target textures briefly presented in the periphery of the visual field (left upper quadrant). After a 10-hr interval filled with either sleep or wakefulness, they were retested first on the trained eye in the trained quadrant and then on the untrained eye and quadrant. In line with prior findings, visual discrimination was globally higher after sleep than after wakefulness, as compared to performance levels at the end of training. Furthermore, discrimination performance was significantly improved only in the sleep condition for the untrained eye in the same quadrant, but also showed a trend to generalize to the untrained eye and untrained quadrant. Our results suggest that sleep-dependent perceptual skills continue developing at a later visual-process stage than the V1 area, where learning is not monocular anymore.

  6. Perceptual crossing: The simplest online paradigm

    Directory of Open Access Journals (Sweden)

    Malika eAuvray

    2012-06-01

    Full Text Available Researchers in social cognition increasingly realize that many phenomena cannot be understood by investigating offline situations only, focusing on individual mechanisms and an observer perspective. There are processes of dynamic emergence specific to online situations, when two or more persons are engaged in a real-time interaction that are more than just the sum of the individual capacities or behaviours, and these require the study of online social interaction. Auvray et al.’s (2009 perceptual crossing paradigm offers possibly the simplest paradigm for studying such online interactions: two persons, a one-dimensional space, one bit of information, and a yes/no answer. Despite, or maybe because of its simplicity, this study has provoked a lot of resonance in different areas of research, including experimental psychology, computer/robot modelling, philosophy, more recently psychopathology, and even in the field of design. In this article, we review and critically assess this body of literature. We give an overview over work on the perceptual crossing paradigm, both concerning behavioural experiments and computational agent modelling, and review the different contexts in which it has been referred to. We discuss the controversy about the possible constitutive role of perceptual crossing for social cognition and other theoretical contexts in which the research has been cited, offering our own interpretation. We conclude with an outlook on future research possibilities, in particular those that could elucidate the link between online interaction dynamics and individual social cognition.

  7. 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.

  8. Attribution and reciprocity

    DEFF Research Database (Denmark)

    Sebald, Alexander Christopher

    2010-01-01

    , in turn, influence behavior. Dufwenberg and Kirchsteiger [Dufwenberg, M., Kirchsteiger, G., 2004. A theory of sequential reciprocity. Games Econ. Behav. 47 (2), 268-298] formalize this empirical finding in their ‘theory of sequential reciprocity'. This paper extends their analysis by moves of chance. More...... precisely, an extended framework is presented which allows for the analysis of strategic interactions of reciprocal agents in situations in which material outcomes also depend on chance. Moves of chance influence the attribution of responsibilities, people's perceptions about the (un)kindness of others and......, hence, their reciprocal behavior. Furthermore, with the help of two applications it is demonstrated how this framework can be used to explain experimental findings showing that people react very differently in outcomewise-identical situations depending on the moves of chance involved....

  9. Perceptual pitch deficits coexist with pitch production difficulties in music but not Mandarin speech.

    Science.gov (United States)

    Yang, Wu-Xia; Feng, Jie; Huang, Wan-Ting; Zhang, Cheng-Xiang; Nan, Yun

    2013-01-01

    Congenital amusia is a musical disorder that mainly affects pitch perception. Among Mandarin speakers, some amusics also have difficulties in processing lexical tones (tone agnosics). To examine to what extent these perceptual deficits may be related to pitch production impairments in music and Mandarin speech, eight amusics, eight tone agnosics, and 12 age- and IQ-matched normal native Mandarin speakers were asked to imitate music note sequences and Mandarin words of comparable lengths. The results indicated that both the amusics and tone agnosics underperformed the controls on musical pitch production. However, tone agnosics performed no worse than the amusics, suggesting that lexical tone perception deficits may not aggravate musical pitch production difficulties. Moreover, these three groups were all able to imitate lexical tones with perfect intelligibility. Taken together, the current study shows that perceptual musical pitch and lexical tone deficits might coexist with musical pitch production difficulties. But at the same time these perceptual pitch deficits might not affect lexical tone production or the intelligibility of the speech words that were produced. The perception-production relationship for pitch among individuals with perceptual pitch deficits may be, therefore, domain-dependent.

  10. Perceptual Pitch Deficits Coexist with Pitch Production Difficulties in Music but Not Mandarin Speech

    Directory of Open Access Journals (Sweden)

    Wu-xia eYang

    2014-01-01

    Full Text Available Congenital amusia is a musical disorder that mainly affects pitch perception. Among Mandarin speakers, some amusics also have difficulties in processing lexical tones (tone agnosics. To examine to what extent these perceptual deficits may be related to pitch production impairments in music and Mandarin speech, 8 amusics, 8 tone agnosics, and 12 age- and IQ-matched normal native Mandarin speakers were asked to imitate music note sequences and Mandarin words of comparable lengths. The results indicated that both the amusics and tone agnosics underperformed the controls on musical pitch production. However, tone agnosics performed no worse than the amusics, suggesting that lexical tone perception deficits may not aggravate musical pitch production difficulties. Moreover, these three groups were all able to imitate lexical tones with perfect intelligibility. Taken together, the current study shows that perceptual musical pitch and lexical tone deficits might coexist with musical pitch production difficulties. But at the same time these perceptual pitch deficits might not affect lexical tone production or the intelligibility of the speech words that were produced. The perception-production relationship for pitch among individuals with perceptual pitch deficits may be, therefore, domain-dependent.

  11. Perceptual pitch deficits coexist with pitch production difficulties in music but not Mandarin speech

    OpenAIRE

    Wu-xia eYang; Jie eFeng; Wan-ting eHuang; Cheng-xiang eZhang; Yun eNan

    2014-01-01

    Congenital amusia is a musical disorder that mainly affects pitch perception. Among Mandarin speakers, some amusics also have difficulties in processing lexical tones (tone agnosics). To examine to what extent these perceptual deficits may be related to pitch production impairments in music and Mandarin speech, eight amusics, eight tone agnosics, and 12 age- and IQ-matched normal native Mandarin speakers were asked to imitate music note sequences and Mandarin words of comparable lengths. The ...

  12. Development of Neural Sensitivity to Face Identity Correlates with Perceptual Discriminability.

    Science.gov (United States)

    Natu, Vaidehi S; Barnett, Michael A; Hartley, Jake; Gomez, Jesse; Stigliani, Anthony; Grill-Spector, Kalanit

    2016-10-19

    Face perception is subserved by a series of face-selective regions in the human ventral stream, which undergo prolonged development from childhood to adulthood. However, it is unknown how neural development of these regions relates to the development of face-perception abilities. Here, we used functional magnetic resonance imaging (fMRI) to measure brain responses of ventral occipitotemporal regions in children (ages, 5-12 years) and adults (ages, 19-34 years) when they viewed faces that parametrically varied in dissimilarity. Since similar faces generate lower responses than dissimilar faces due to fMRI adaptation, this design objectively evaluates neural sensitivity to face identity across development. Additionally, a subset of subjects participated in a behavioral experiment to assess perceptual discriminability of face identity. Our data reveal three main findings: (1) neural sensitivity to face identity increases with age in face-selective but not object-selective regions; (2) the amplitude of responses to faces increases with age in both face-selective and object-selective regions; and (3) perceptual discriminability of face identity is correlated with the neural sensitivity to face identity of face-selective regions. In contrast, perceptual discriminability is not correlated with the amplitude of response in face-selective regions or of responses of object-selective regions. These data suggest that developmental increases in neural sensitivity to face identity in face-selective regions improve perceptual discriminability of faces. Our findings significantly advance the understanding of the neural mechanisms of development of face perception and open new avenues for using fMRI adaptation to study the neural development of high-level visual and cognitive functions more broadly.

  13. 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...

  14. The role of perceptual load in object recognition

    OpenAIRE

    Lavie, Nilli; Lin, Zhicheng; Zokaei, Nahid; Thoma, Volker

    2009-01-01

    Predictions from perceptual load theory (Lavie, 1995, 2005) regarding object recognition across the same or different viewpoints were tested. Results showed that high perceptual load reduces distracter\\ud recognition levels despite always presenting distracter objects from the same view. They also showed that the levels of distracter recognition were unaffected by a change in the distracter object view under conditions of low perceptual load. These results were found both with repetition prim...

  15. Paranormal belief and attributional style.

    Science.gov (United States)

    Dudley, R T; Whisnand, E A

    2000-06-01

    52 college students completed Tobacyk's 1988 Revised Paranormal Belief Scale and Peterson, Semmel, von Baeyer, Abramson, Metalsky, and Seligman's 1982 Attributional Style Questionnaire. Analysis showed significantly higher depressive attributional styles among high scorers on paranormal phenomena than low scorers.

  16. Conceptual and Methodological Concerns in the Theory of Perceptual Load

    Directory of Open Access Journals (Sweden)

    Hanna eBenoni

    2013-08-01

    Full Text Available The present paper provides a short critical review of the theory of perceptual load. It closely examines the basic tenets and assumptions of the theory and identifies major conceptual and methodological problems that have been largely ignored in the literature. The discussion focuses on problems in the definition of the concept of perceptual load, on the circularity in the characterization and manipulation of perceptual load and the confusion between the concept of perceptual load and its operationalization. The paper also selectively reviews evidence supporting the theory as well as inconsistent evidence which proposed alternative dominant factors influencing the efficacy of attentional selection.

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

    Science.gov (United States)

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

    2010-04-21

    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 subjects, aged 55-76years, were randomly assigned to training or control groups. Visual-span profiles (plots of letter-recognition accuracy as a function of horizontal letter position) and RSVP reading speeds were measured at 10 degrees above and below fixation during pre- and post-tests for all subjects. Training consisted of repeated measurements of visual-span profiles at 10 degrees below fixation, in four daily sessions. The control subjects did not receive any training. Perceptual learning enlarged the visual spans in both trained (lower) and untrained (upper) visual fields. Reading speed improved in the trained field by 60% when the trained print size was used. The training benefits for these older subjects were weaker than the training benefits for young adults found by Chung et al. Despite the weaker training benefits, perceptual learning remains a potential option for low-vision reading rehabilitation among older adults.

  18. Velopharyngeal function assessment in patients with cleft palate: perceptual speech assessment versus nasopharyngoscopy.

    Science.gov (United States)

    Ma, Li; Shi, Bing; Li, Yang; Zheng, Qian

    2013-07-01

    There is no doubt that perceptual speech assessment and instrumental examination could provide different diagnostic information on patients with cleft palate (CP), but not all patients simultaneously need the 2 examinations. So the purposes of this study were to explore a simple and effective evaluation method to assess velopharyngeal function and to investigate speech traits that affect the diagnosis of velopharyngeal function in patients with CP. The investigators implemented a retrospective study, and 247 postoperative patients with CP were selected, including 155 boys and 92 girls, with a mean (SD) age of 13 years and 2 months (7 years and 7 months). All of these patients were assessed by perceptual speech evaluation and nasopharyngoscopy after surgery, and the result was divided into velopharyngeal closure (VPC), velopharyngeal insufficiency, and marginal VPC. The number of diagnostic consistency patients was 170 (VPC, 51 patients; velopharyngeal insufficiency, 115 patients; marginal VPC, 4 patients), and the consistent ratio was 68.83%. There was no significant difference between perceptual speech assessment and nasopharyngoscopy. Furthermore, the difference in distribution of hypernasality between the consistent group and the inconsistent group was significant. In addition, the correlation analysis indicated that surgical age, hypernasality, nasal emission, and compensatory articulation were correlated with the velopharyngeal function (P velopharyngeal function. Much more attention should be paid to the surgical age, the alteration of hypernasality, nasal emission, and compensatory articulation during CP therapy.

  19. Perceptual distinctiveness produces long-lasting priming of pop-out.

    Science.gov (United States)

    Thomson, David R; Milliken, Bruce

    2012-04-01

    Maljkovic and Nakayama (1994) demonstrated memory influences in singleton search from one trial to the next, an effect they termed priming of pop-out (PoP). This effect was described as resulting from the persistence of an implicit memory trace, the influence of which could be observed for around five to eight subsequent trials. The seemingly short-lived nature of this priming effect has been attributed to decay of the underlying memory representation that occurs when attention is directed to intervening search items, even when such items are perceptually dissimilar from the search trials upon which PoP is measured (Maljkovic & Nakayama, 2000). The present study reexamines the role of perceptual similarity as a mechanism of interference by examining the influence on PoP of rare search trials that were perceptually distinct with respect to the other, common trials. Long-lasting (n - 16) PoP was observed for rare trials that were composed of distinct target/distractor colors, suggesting that PoP can be observed across at least twice as many trials as has previously been reported. Thus, the time span across which PoP can be measured depends heavily on the nature of the intervening search displays, a result that must be accommodated by current theoretical accounts of PoP.

  20. Assessing the applied benefits of perceptual training: Lessons from studies of training working-memory.

    Science.gov (United States)

    Jacoby, Nori; Ahissar, Merav

    2015-01-01

    In the 1980s to 1990s, studies of perceptual learning focused on the specificity of training to basic visual attributes such as retinal position and orientation. These studies were considered scientifically innovative since they suggested the existence of plasticity in the early stimulus-specific sensory cortex. Twenty years later, perceptual training has gradually shifted to potential applications, and research tends to be devoted to showing transfer. In this paper we analyze two key methodological issues related to the interpretation of transfer. The first has to do with the absence of a control group or the sole use of a test-retest group in traditional perceptual training studies. The second deals with claims of transfer based on the correlation between improvement on the trained and transfer tasks. We analyze examples from the general intelligence literature dealing with the impact on general intelligence of training on a working memory task. The re-analyses show that the reports of a significantly larger transfer of the trained group over the test-retest group fail to replicate when transfer is compared to an actively trained group. Furthermore, the correlations reported in this literature between gains on the trained and transfer tasks can be replicated even when no transfer is assumed.

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

    Directory of Open Access Journals (Sweden)

    Eduardo eMercado

    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 separability of featural and configural information in congenital prosopagnosia.

    Science.gov (United States)

    Kimchi, Ruth; Behrmann, Marlene; Avidan, Galia; Amishav, Rama

    2012-01-01

    The deficit in face recognition in individuals with prosopagnosia has often been attributed to an underlying impairment in holistic processing. Exactly what constitutes holistic processing has remained controversial, however. Here, we compare how configural information and featural information interact during face processing in a group of individuals with congenital prosopagnosia (CP) and matched controls. We adopted Amishav and Kimchi's version of Garner's speeded classification task, in which observers classify upright faces based on configural (intereyes and nose-mouth spacing) or featural (shape of eyes, nose, and mouth) information while the other dimension remains constant or varied randomly. We replicated the finding that normal observers evince symmetric Garner interference--failure to selectively attend to features without being influenced by irrelevant variation in configuration, and vice versa--indicating that featural and configural information are integral in normal face processing. In contrast, the CPs showed no Garner interference: They were able to attend to configural information without interference from irrelevant variation in featural information, and they were able to attend to featural information without interference from irrelevant variation in configural information. The absence of Garner interference in CP provides strong evidence that featural information and configural information are perceptually separable in CP's face processing. These findings indicate that CPs do not perceive faces holistically; rather, they process featural and configural information independently.

  3. Nicotine facilitates memory consolidation in perceptual learning.

    Science.gov (United States)

    Beer, Anton L; Vartak, Devavrat; Greenlee, Mark W

    2013-01-01

    Perceptual learning is a special type of non-declarative learning that involves experience-dependent plasticity in sensory cortices. The cholinergic system is known to modulate declarative learning. In particular, reduced levels or efficacy of the neurotransmitter acetylcholine were found to facilitate declarative memory consolidation. However, little is known about the role of the cholinergic system in memory consolidation of non-declarative learning. Here we compared two groups of non-smoking men who learned a visual texture discrimination task (TDT). One group received chewing tobacco containing nicotine for 1 h directly following the TDT training. The other group received a similar tasting control substance without nicotine. Electroencephalographic recordings during substance consumption showed reduced alpha activity and P300 latencies in the nicotine group compared to the control group. When re-tested on the TDT the following day, both groups responded more accurately and more rapidly than during training. These improvements were specific to the retinal location and orientation of the texture elements of the TDT suggesting that learning involved early visual cortex. A group comparison showed that learning effects were more pronounced in the nicotine group than in the control group. These findings suggest that oral consumption of nicotine enhances the efficacy of nicotinic acetylcholine receptors. Our findings further suggest that enhanced efficacy of the cholinergic system facilitates memory consolidation in perceptual learning (and possibly other types of non-declarative learning). In that regard acetylcholine seems to affect consolidation processes in perceptual learning in a different manner than in declarative learning. Alternatively, our findings might reflect dose-dependent cholinergic modulation of memory consolidation. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

  4. 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.

  5. Evidence of a Transition from Perceptual to Category Induction in 3- to 9-Year-Old Children

    Science.gov (United States)

    Badger, Julia R.; Shapiro, Laura R.

    2012-01-01

    We examined whether inductive reasoning development is better characterized by accounts assuming an early category bias versus an early perceptual bias. We trained 264 children aged 3 to 9 years to categorize novel insects using a rule that directly pitted category membership against appearance. This was followed by an induction task with…

  6. Consequences of comorbidity of developmental coordination disorders and learning disabilities for severity and pattern of perceptual-motor dysfunction

    NARCIS (Netherlands)

    Jongmans, MJ; Smits-Engelsman, BCM; Schoemaker, MM

    2003-01-01

    Children with developmental coordination disorder (DCD) have difficulty learning and performing age-appropriate perceptual-motor skills in the absence of diagnosable neurological disorders. Descriptive studies have shown that comorbidity of DCD exists with attention-deficit/hyperactivity disorder (A

  7. Motor Development and the Mind: The Potential Role of Motor Abilities as a Determinant of Aspects of Perceptual Development.

    Science.gov (United States)

    Bushnell, Emily W.; Boudreau, J. Paul

    1993-01-01

    Emphasizes the role that motor development may play in determining developmental sequences in other domains, such as haptic or tactile perception and depth perception. Maintains that there is a high degree of fit between the developmental sequence in which certain perceptual sensitivities unfold and the ages at which the corresponding motor…

  8. Effects of an Integrated Physical Education/Music Program in Changing Early Childhood Perceptual-Motor Performance.

    Science.gov (United States)

    Brown, Judy; And Others

    1981-01-01

    Two approaches to facilitating perceptual-motor development in children ages 4-6 were investigated. Fifteen children (the experimental group) received integrated physical education/music instruction based on Kodaly and Dalcroze (Eurhythmics) concepts. The control group received movement exploration and self-testing instruction. Significant…

  9. Instantaneous Frequency Attribute Comparison

    Science.gov (United States)

    Yedlin, M. J.; Margrave, G. F.; Ben Horin, Y.

    2013-12-01

    The instantaneous seismic data attribute provides a different means of seismic interpretation, for all types of seismic data. It first came to the fore in exploration seismology in the classic paper of Taner et al (1979), entitled " Complex seismic trace analysis". Subsequently a vast literature has been accumulated on the subject, which has been given an excellent review by Barnes (1992). In this research we will compare two different methods of computation of the instantaneous frequency. The first method is based on the original idea of Taner et al (1979) and utilizes the derivative of the instantaneous phase of the analytic signal. The second method is based on the computation of the power centroid of the time-frequency spectrum, obtained using either the Gabor Transform as computed by Margrave et al (2011) or the Stockwell Transform as described by Stockwell et al (1996). We will apply both methods to exploration seismic data and the DPRK events recorded in 2006 and 2013. In applying the classical analytic signal technique, which is known to be unstable, due to the division of the square of the envelope, we will incorporate the stabilization and smoothing method proposed in the two paper of Fomel (2007). This method employs linear inverse theory regularization coupled with the application of an appropriate data smoother. The centroid method application is straightforward and is based on the very complete theoretical analysis provided in elegant fashion by Cohen (1995). While the results of the two methods are very similar, noticeable differences are seen at the data edges. This is most likely due to the edge effects of the smoothing operator in the Fomel method, which is more computationally intensive, when an optimal search of the regularization parameter is done. An advantage of the centroid method is the intrinsic smoothing of the data, which is inherent in the sliding window application used in all Short-Time Fourier Transform methods. The Fomel technique

  10. 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…

  11. Perceptual advantage for category-relevant perceptual dimensions: The case of shape and motion

    Directory of Open Access Journals (Sweden)

    Jonathan R Folstein

    2014-12-01

    Full Text Available Category learning facilitates perception along relevant stimulus dimensions, even when tested in a discrimination task that does not require categorization. While this general phenomenon has been demonstrated previously, perceptual facilitation along dimensions has been documented by measuring different specific phenomena in different studies using different kinds of objects. Across several object domains, there is support for acquired distinctiveness, the stretching of a perceptual dimension relevant to learned categories. Studies using faces and studies using simple separable visual dimensions have also found evidence of acquired equivalence, the shrinking of a perceptual dimension irrelevant to learned categories, and categorical perception, the local stretching across the category boundary. These later two effects are rarely observed with complex non-face objects. Failures to find these effects with complex non-face objects may have been because the dimensions tested previously were perceptually integrated. Here we tested effects of category learning with non-face objects categorized along dimensions that have been found to be processed by different areas of the brain, shape and motion. While we replicated acquired distinctiveness, we found no evidence for acquired equivalence or categorical perception.

  12. Prolonged perceptual learning of positional acuity in adult amblyopia: perceptual template retuning dynamics.

    Science.gov (United States)

    Li, Roger W; Klein, Stanley A; Levi, Dennis M

    2008-12-24

    Amblyopia is a developmental abnormality that results in physiological alterations in the visual cortex and impairs form vision. It is often successfully treated by patching the sound eye in infants and young children, but is generally considered to be untreatable in adults. However, a number of recent studies suggest that repetitive practice of a visual task using the amblyopic eye results in improved performance in both children and adults with amblyopia. These perceptual learning studies have used relatively brief periods of practice; however, clinical studies have shown that the time-constant for successful patching is long. The time-constant for perceptual learning in amblyopia is still unknown. Here we show that the time-constant for perceptual learning depends on the degree of amblyopia. Severe amblyopia requires >50 h (approximately equal to 35,000 trials) to reach plateau, yielding as much as a five-fold improvement in performance at a rate of approximately equal to 1.5%/h. There is significant transfer of learning from the amblyopic to the dominant eye, suggesting that the learning reflects alterations in higher decision stages of processing. Using a reverse correlation technique, we document, for the first time, a dynamic retuning of the amblyopic perceptual decision template and a substantial reduction in internal spatial distortion. These results show that the mature amblyopic brain is surprisingly malleable, and point to more intensive treatment methods for amblyopia.

  13. Physiological attributes of triathletes.

    Science.gov (United States)

    Suriano, R; Bishop, D

    2010-05-01

    Triathlons of all distances can be considered endurance events and consist of the individual disciplines of swimming, cycling and running which are generally completed in this sequential order. While it is expected that elite triathletes would possess high values for submaximal and maximal measures of aerobic fitness, little is known about how these values compare with those of single-sport endurance athletes. Earlier reviews, conducted in the 1980s, concluded that triathletes possessed lower V(O2(max)) values than other endurance athletes. An update of comparisons is of interest to determine if the physiological capacities of elite triathletes now reflect those of single-sport athletes or whether these physiological capacities are compromised by the requirement to cross-train for three different disciplines. It was found that although differences in the physiological attributes during swimming, cycling and running are evident among triathletes, those who compete at an international level possess V(O2(max)) values that are indicative of success in endurance-based individual sports. Furthermore, various physiological parameters at submaximal workloads have been used to describe the capacities of these athletes. Only a few studies have reported the lactate threshold among triathletes with the majority of studies reporting the ventilatory threshold. Although observed differences among triathletes for both these submaximal measures are complicated by the various methods used to determine them, the reported values for triathletes are similar to those for trained cyclists and runners. Thus, from the limited data available, it appears that triathletes are able to obtain similar physiological values as single-sport athletes despite dividing their training time among three disciplines.

  14. A ratio model of perceptual transparency.

    Science.gov (United States)

    Tommasi, M

    1999-12-01

    A ratio model of the achromatic transparency of a phenomenal surface on a bipartite background is proposed. The model asserts that transparency corresponds to the evaluation of the ratio of the lightness difference inside the transparent surface to the difference in reference lightness inside the background. It applies to both balanced and unbalanced transparency. The ratio model was compared experimentally with the previous perceptual model of achromatic transparency proposed by Metelli. Each model was tested by comparing the rated with the predicted transparency. Analysis shows that the ratio model provides better predictions of transparency than those provided by Metelli's model.

  15. Perceptual Grouping via Untangling Gestalt Principles

    DEFF Research Database (Denmark)

    Qi, Yonggang; Guo, Jun; Li, Yi

    2013-01-01

    Gestalt principles, a set of conjoining rules derived from hu- man visual studies, have been known to play an important role in computer vision. Many applications such as image segmentation, contour grouping and scene understanding of- ten rely on such rules to work. However, the problem of Gestalt...... the importance of Gestalt rules by solving a learning to rank problem, and formulate a multi-label graph-cuts algo- rithm to group image primitives while taking into account the learned Gestalt confliction. Our experiment results confirm the existence of Gestalt confliction in perceptual grouping and demonstrate...

  16. JPEG 2000 Encoding with Perceptual Distortion Control

    Science.gov (United States)

    Watson, Andrew B.; Liu, Zhen; Karam, Lina J.

    2008-01-01

    An alternative approach has been devised for encoding image data in compliance with JPEG 2000, the most recent still-image data-compression standard of the Joint Photographic Experts Group. Heretofore, JPEG 2000 encoding has been implemented by several related schemes classified as rate-based distortion-minimization encoding. In each of these schemes, the end user specifies a desired bit rate and the encoding algorithm strives to attain that rate while minimizing a mean squared error (MSE). While rate-based distortion minimization is appropriate for transmitting data over a limited-bandwidth channel, it is not the best approach for applications in which the perceptual quality of reconstructed images is a major consideration. A better approach for such applications is the present alternative one, denoted perceptual distortion control, in which the encoding algorithm strives to compress data to the lowest bit rate that yields at least a specified level of perceptual image quality. Some additional background information on JPEG 2000 is prerequisite to a meaningful summary of JPEG encoding with perceptual distortion control. The JPEG 2000 encoding process includes two subprocesses known as tier-1 and tier-2 coding. In order to minimize the MSE for the desired bit rate, a rate-distortion- optimization subprocess is introduced between the tier-1 and tier-2 subprocesses. In tier-1 coding, each coding block is independently bit-plane coded from the most-significant-bit (MSB) plane to the least-significant-bit (LSB) plane, using three coding passes (except for the MSB plane, which is coded using only one "clean up" coding pass). For M bit planes, this subprocess involves a total number of (3M - 2) coding passes. An embedded bit stream is then generated for each coding block. Information on the reduction in distortion and the increase in the bit rate associated with each coding pass is collected. This information is then used in a rate-control procedure to determine the

  17. Homogeneity of Prototypical Attributes in Soccer Teams

    Directory of Open Access Journals (Sweden)

    Christian Zepp

    2015-09-01

    Full Text Available Research indicates that the homogeneous perception of prototypical attributes influences several intragroup processes. The aim of the present study was to describe the homogeneous perception of the prototype and to identify specific prototypical subcategories, which are perceived as homogeneous within sport teams. The sample consists of N = 20 soccer teams with a total of N = 278 athletes (age M = 23.5 years, SD = 5.0 years. The results reveal that subcategories describing the cohesiveness of the team and motivational attributes are mentioned homogeneously within sport teams. In addition, gender, identification, team size, and the championship ranking significantly correlate with the homogeneous perception of prototypical attributes. The results are discussed on the basis of theoretical and practical implications.

  18. Facial expression recognition in perceptual color space.

    Science.gov (United States)

    Lajevardi, Seyed Mehdi; Wu, Hong Ren

    2012-08-01

    This paper introduces a tensor perceptual color framework (TPCF) for facial expression recognition (FER), which is based on information contained in color facial images. The TPCF enables multi-linear image analysis in different color spaces and demonstrates that color components provide additional information for robust FER. Using this framework, the components (in either RGB, YCbCr, CIELab or CIELuv space) of color images are unfolded to two-dimensional (2- D) tensors based on multi-linear algebra and tensor concepts, from which the features are extracted by Log-Gabor filters. The mutual information quotient (MIQ) method is employed for feature selection. These features are classified using a multi-class linear discriminant analysis (LDA) classifier. The effectiveness of color information on FER using low-resolution and facial expression images with illumination variations is assessed for performance evaluation. Experimental results demonstrate that color information has significant potential to improve emotion recognition performance due to the complementary characteristics of image textures. Furthermore, the perceptual color spaces (CIELab and CIELuv) are better overall for facial expression recognition than other color spaces by providing more efficient and robust performance for facial expression recognition using facial images with illumination variation.

  19. On the filter approach to perceptual transparency.

    Science.gov (United States)

    Faul, Franz; Ekroll, Vebjørn

    2011-06-09

    In F. Faul and V. Ekroll (2002), we proposed a filter model of perceptual transparency that describes typical color changes caused by optical filters and accurately predicts perceived transparency. Here, we provide a more elaborate analysis of this model: (A) We address the question of how the model parameters can be estimated in a robust way. (B) We show that the parameters of the original model, which are closely related to physical properties, can be transformed into the alternative parameters hue H, saturation S, transmittance V, and clarity C that better reflect perceptual dimensions of perceived transparency. (C) We investigate the relation of H, S, V, and C to the physical parameters of optical filters and show that C is closely related to the refractive index of the filter, whereas V and S are closely related to its thickness. We also demonstrate that the latter relationship can be used to estimate relative filter thickness from S and V. (D) We investigate restrictions on S that result from properties of color space and determine its distribution under realistic choices of physical parameters. (E) We experimentally determine iso-saturation curves that yield nominal saturation values for filters of different hue such that they appear equally saturated.

  20. 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.

  1. 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.

  2. Dysarthria in Friedreich's ataxia: a perceptual analysis.

    Science.gov (United States)

    Folker, Joanne; Murdoch, Bruce; Cahill, Louise; Delatycki, Martin; Corben, Louise; Vogel, Adam

    2010-01-01

    The aims of this study were to: (1) evaluate the perceptual speech dimensions, speech intelligibility and dysarthria severity of a group of individuals diagnosed with Friedreich's ataxia (FRDA); (2) determine the presence of subgroups within FRDA dysarthria; (3) investigate the relationship between the speech outcome and the clinical factors of disease progression. The study included 38 individuals (21 female, 17 male) with a confirmed diagnosis of FRDA. A group of 20 non-neurologically impaired individuals served as controls. Perceptual analysis, investigating 30 different dimensions of speech, was conducted on a speech sample obtained from each participant. In addition, the Assessment of Intelligibility of Dysarthria Speech was administered. All FRDA participants presented with dysarthria with severities ranging from mild to moderate. Cluster analysis revealed 3 subgroups, the first presenting with mild dysarthric symptoms, the second with increased velopharyngeal involvement and the third characterized by increased laryngeal dysfunction. Dysarthria severity showed a significant correlation to disease duration but to no other clinical measure. The findings support the notion of subgroups in FRDA dysarthria, representing distinct impairments of the speech mechanism and perhaps reflective of differing evolutions beyond the cerebellum.

  3. 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.

  4. 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.

  5. 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…

  6. Perceptual biases in relation to paranormal and conspiracy beliefs

    NARCIS (Netherlands)

    van Elk, M.

    2015-01-01

    Previous studies have shown that one’s prior beliefs have a strong effect on perceptual decision-making and attentional processing. The present study extends these findings by investigating how individual differences in paranormal and conspiracy beliefs are related to perceptual and attentional bias

  7. 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…

  8. Perceptual Learning: 12-Month-Olds' Discrimination of Monkey Faces

    Science.gov (United States)

    Fair, Joseph; Flom, Ross; Jones, Jacob; Martin, Justin

    2012-01-01

    Six-month-olds reliably discriminate different monkey and human faces whereas 9-month-olds only discriminate different human faces. It is often falsely assumed that perceptual narrowing reflects a permanent change in perceptual abilities. In 3 experiments, ninety-six 12-month-olds' discrimination of unfamiliar monkey faces was examined. Following…

  9. Ambiguity Tolerance and Perceptual Learning Styles of Chinese EFL Learners

    Science.gov (United States)

    Li, Haishan; He, Qingshun

    2016-01-01

    Ambiguity tolerance and perceptual learning styles are the two influential elements showing individual differences in EFL learning. This research is intended to explore the relationship between Chinese EFL learners' ambiguity tolerance and their preferred perceptual learning styles. The findings include (1) the learners are sensitive to English…

  10. Harnessing the Wandering Mind: The Role of Perceptual Load

    Science.gov (United States)

    Forster, Sophie; Lavie, Nilli

    2009-01-01

    Perceptual load is a key determinant of distraction by task-irrelevant stimuli (e.g., Lavie, N. (2005). "Distracted and confused?: Selective attention under load." "Trends in Cognitive Sciences," 9, 75-82). Here we establish the role of perceptual load in determining an internal form of distraction by task-unrelated thoughts (TUTs or…

  11. Perceptual Specificity Effects in Rereading: Evidence from Eye Movements

    Science.gov (United States)

    Sheridan, Heather; Reingold, Eyal M.

    2012-01-01

    The present experiments examined perceptual specificity effects using a rereading paradigm. Eye movements were monitored while participants read the same target word twice, in two different low-constraint sentence frames. The congruency of perceptual processing was manipulated by either presenting the target word in the same distortion typography…

  12. Bayesian Face Recognition and Perceptual Narrowing in Face-Space

    Science.gov (United States)

    Balas, Benjamin

    2012-01-01

    During the first year of life, infants' face recognition abilities are subject to "perceptual narrowing", the end result of which is that observers lose the ability to distinguish previously discriminable faces (e.g. other-race faces) from one another. Perceptual narrowing has been reported for faces of different species and different races, in…

  13. The Role of Perceptual Load in Object Recognition

    Science.gov (United States)

    Lavie, Nilli; Lin, Zhicheng; Zokaei, Nahid; Thoma, Volker

    2009-01-01

    Predictions from perceptual load theory (Lavie, 1995, 2005) regarding object recognition across the same or different viewpoints were tested. Results showed that high perceptual load reduces distracter recognition levels despite always presenting distracter objects from the same view. They also showed that the levels of distracter recognition were…

  14. The Role of Perceptual Load in Inattentional Blindness

    Science.gov (United States)

    Cartwright-Finch, Ula; Lavie, Nilli

    2007-01-01

    Perceptual load theory offers a resolution to the long-standing early vs. late selection debate over whether task-irrelevant stimuli are perceived, suggesting that irrelevant perception depends upon the perceptual load of task-relevant processing. However, previous evidence for this theory has relied on RTs and neuroimaging. Here we tested the…

  15. Volitional action as perceptual detection: predictors of conscious intention in adolescents with tic disorders.

    Science.gov (United States)

    Ganos, Christos; Asmuss, Luisa; Bongert, Jens; Brandt, Valerie; Münchau, Alexander; Haggard, Patrick

    2015-03-01

    Voluntary actions are accompanied by a distinctive subjective experience, so that they feel quite different from physically similar involuntary movements. However, the nature and origin of this experience of volition remain unclear. Voluntary actions emerge during early childhood, in parallel with reduction of involuntary movements. However, the available markers of the experience of volition, notably Libet's mental chronometry of intention, cannot readily be used in young children. In Gilles de la Tourette syndrome (GTS), however, involuntary tic movements may coexist with voluntary control into adulthood. Therefore, adolescents with GTS could potentially confuse the two classes of movement. We have measured the temporal experience of voluntary action in a well-characterised group of adolescents with GTS, and age-matched controls. We replicated previous reports of a conscious intention occurring a few hundred milliseconds prior to voluntary keypress actions. Multiple regression across 25 patients' results showed that age and trait tic severity did not influence the experience of conscious intention. However, patients with stronger premonitory urges prior to tics showed significantly later conscious intentions, suggesting that the anticipatory experience of one's own volition involves a perceptual discrimination between potentially competing pre-movement signals. Patients who were more able to voluntarily suppress their tics showed significantly earlier conscious intention, suggesting that the perceptual discrimination between different action classes may also contribute to voluntary control of tics. We suggest that the brain learns voluntary control by perceptually discriminating a special class of internal 'intentional' signals, allowing them to emerge from motor noise.

  16. WAIS-III processing speed index scores after TBI: the influence of working memory, psychomotor speed and perceptual processing.

    Science.gov (United States)

    Kennedy, Jan E; Clement, Pamelia F; Curtiss, Glenn

    2003-08-01

    This study investigates the extent to which working memory, motor speed and perceptual processing speed influence Wechsler Adult Intelligence Scale-III (WAIS-III) Processing Speed Index (PSI) scores. Sixty-eight adult outpatients with Traumatic Brain Injury (TBI) of varying severity and complete data on all outcome measures were identified. Two cases with outlying values on one outcome measure were omitted from the final sample. Working memory was measured by the Working Memory Index score from the WAIS-III. Motor speed was measured as score on the Halstead-Reitan Finger Oscillation Test (finger tapping) and perceptual processing as score on the Trail Making Test--Part B. In hierarchical multiple regression analyses, working memory accounted for 10% of the variance in PSI scores, whereas motor speed only accounted for 3%. An independent measure of perceptual processing, Trail Making Test--B, accounted for 26% of the variance in WAIS-III PSI scores. The total variance accounted for by the three factors was 56%. Findings confirm that the WAIS-III PSI scores of individuals who have received a TBI reflect perceptual processing speed, with an additional component attributable to working memory. Motor speed made only a small contribution to WAIS-III PSI scores in the present sample.

  17. Exogenous attention facilitates location transfer of perceptual learning.

    Science.gov (United States)

    Donovan, Ian; Szpiro, Sarit; Carrasco, Marisa

    2015-01-01

    Perceptual skills can be improved through practice on a perceptual task, even in adulthood. Visual perceptual learning is known to be mostly specific to the trained retinal location, which is considered as evidence of neural plasticity in retinotopic early visual cortex. Recent findings demonstrate that transfer of learning to untrained locations can occur under some specific training procedures. Here, we evaluated whether exogenous attention facilitates transfer of perceptual learning to untrained locations, both adjacent to the trained locations (Experiment 1) and distant from them (Experiment 2). The results reveal that attention facilitates transfer of perceptual learning to untrained locations in both experiments, and that this transfer occurs both within and across visual hemifields. These findings show that training with exogenous attention is a powerful regime that is able to overcome the major limitation of location specificity.

  18. Reliability and validity of scores on the Slosson Visual Perceptual Skill Screener.

    Science.gov (United States)

    Erford, Bradley T; Snyder, Henry

    2004-10-01

    Psychometric characteristics of the Slosson Visual Perceptual Skill Screener were studied using three independent samples of 595 boys and 578 girls ages 5 to 10 years. Adequate characteristics for item selection were indicated by item difficulty (Mdn=.49) and item discrimination (Mdn=.59). Interitem consistency of .93 (n1 = 1,045) was recorded for the total scale, while 30-day test-retest reliability was .80 (n2=55). Convergent validity was estimated using the Bender Visual-Motor Gestalt test (Koppitz developmental scoring system; r = .43, n3=47), the Developmental Test of Visuo-motor Integration, Visual Perception subtest (r =.62, n3 =73), and the Test of Visual Perceptual Skills-Revised-Nonmotor Total Score (r = .63, n2 =59).

  19. Perceptual evaluation of motor speech following treatment for childhood cerebellar tumour.

    Science.gov (United States)

    Cornwell, Petrea L; Murdoch, Bruce E; Ward, Elizabeth C; Kellie, Stewart

    2003-12-01

    The speech characteristics, oromotor function and speech intelligibility of a group of children treated for cerebellar tumour (CT) was investigated perceptually. Assessment of these areas was performed on 11 children treated for CT with dysarthric speech as well as 21 non-neurologically impaired controls matched for age and sex to obtain a comprehensive perceptual profile of their speech and oromotor mechanism. Contributing to the perception of dysarthria were a number of deviant speech dimensions including imprecision of consonants, hoarseness and decreased pitch variation, as well as a reduction in overall speech intelligibility for both sentences and connected speech. Oromotor assessment revealed deficits in lip, tongue and laryngeal function, particularly relating to deficits in timing and coordination of movements. The most salient features of the dysarthria seen in children treated for CT were the mild nature of the speech disorder and clustering of speech deficits in the prosodic, phonatory and articulatory aspects of speech production.

  20. Customers' attributional judgments towards complaint handling in airline service: a confirmatory study based on attribution theory.

    Science.gov (United States)

    Chiou, Wen-Bin

    2007-06-01

    Besides flight safety, complaint handling plays a crucial role in airline service. Based upon Kelley's attribution theory, in the present study customers' attributions were examined under different conditions of complaint handling by the airlines. There were 531 passengers (216 women; ages 21 to 63 years, M = 41.5, SD = 11.1) with experiences of customer complaints who were recruited while awaiting boarding. Participants received one hypothetical scenario of three attributional conditions about complaint handling and then reported their attributional judgments. The findings indicated that the passengers were most likely to attribute the company's complaint handling to unconditional compliance when the airline company reacted to customer complaints under low distinctiveness, high consistency, and when consensus among the airlines was low. On the other hand, most passengers attributed the company's complaint handling to conditional compliance under the conditions in which distinctiveness, consistency, and consensus were all high. The results provide further insights into how different policies of complaint management affect customers' attributions. Future directions and managerial implications are also discussed.

  1. Attribute-Value Functions as Global Interpretations of Attribute Importance

    NARCIS (Netherlands)

    Ittersum, van K.; Pennings, J.M.E.

    2012-01-01

    In order to better understand decision maker’s perceptions of the importance of attributes, Goldstein (1990) differentiates between global and local interpretations of attribute importance. While the appreciation for the distinction is growing, research on the relationship between measures of global

  2. Acoustic and perceptual characteristics of voicing in fricatives and fricative clusters.

    Science.gov (United States)

    Stevens, K N; Blumstein, S E; Glicksman, L; Burton, M; Kurowski, K

    1992-05-01

    Several types of measurements were made to determine the acoustic characteristics that distinguish between voiced and voiceless fricatives in various phonetic environments. The selection of measurements was based on a theoretical analysis that indicated the acoustic and aerodynamic attributes at the boundaries between fricatives and vowels. As expected, glottal vibration extended over a longer time in the obstruent interval for voiced fricatives than for voiceless fricatives, and there were more extensive transitions of the first formant adjacent to voiced fricatives than for the voiceless cognates. When two fricatives with different voicing were adjacent, there were substantial modifications of these acoustic attributes, particularly for the syllable-final fricative. In some cases, these modifications leads to complete assimilation of the voicing feature. Several perceptual studies with synthetic vowel-consonant-vowel stimuli and with edited natural stimuli examined the role of consonant duration, extent and location of glottal vibration, and extent of formant transitions on the identification of the voicing characteristics of fricatives. The perceptual results were in general consistent with the acoustic observations and with expectations based on the theoretical model. The results suggest that listeners base their voicing judgments of intervocalic fricatives on an assessment of the time interval in the fricative during which there is no glottal vibration. This time interval must exceed about 60 ms if the fricative is to be judged as voiceless, except that a small correction to this threshold is applied depending on the extent to which the first-formant transitions are truncated at the consonant boundaries.

  3. 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.

  4. 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),

  5. Rich Man, Poor Man: Developmental Differences in Attributions and Perceptions

    Science.gov (United States)

    Sigelman, Carol K.

    2012-01-01

    In an examination guided by cognitive developmental and attribution theory of how explanations of wealth and poverty and perceptions of rich and poor people change with age and are interrelated, 6-, 10-, and 14-year-olds (N = 88) were asked for their causal attributions and trait judgments concerning a rich man and a poor man. First graders, like…

  6. Perceptual effects in auralization of virtual rooms

    Science.gov (United States)

    Kleiner, Mendel; Larsson, Pontus; Vastfjall, Daniel; Torres, Rendell R.

    2002-05-01

    By using various types of binaural simulation (or ``auralization'') of physical environments, it is now possible to study basic perceptual issues relevant to room acoustics, as well to simulate the acoustic conditions found in concert halls and other auditoria. Binaural simulation of physical spaces in general is also important to virtual reality systems. This presentation will begin with an overview of the issues encountered in the auralization of room and other environments. We will then discuss the influence of various approximations in room modeling, in particular, edge- and surface scattering, on the perceived room response. Finally, we will discuss cross-modal effects, such as the influence of visual cues on the perception of auditory cues, and the influence of cross-modal effects on the judgement of ``perceived presence'' and the rating of room acoustic quality.

  7. Perceptual grouping determines haptic contextual modulation.

    Science.gov (United States)

    Overvliet, K E; Sayim, B

    2016-09-01

    Since the early phenomenological demonstrations of Gestalt principles, one of the major challenges of Gestalt psychology has been to quantify these principles. Here, we show that contextual modulation, i.e. the influence of context on target perception, can be used as a tool to quantify perceptual grouping in the haptic domain, similar to the visual domain. We investigated the influence of target-flanker grouping on performance in haptic vernier offset discrimination. We hypothesized that when, despite the apparent differences between vision and haptics, similar grouping principles are operational, a similar pattern of flanker interference would be observed in the haptic as in the visual domain. Participants discriminated the offset of a haptic vernier. The vernier was flanked by different flanker configurations: no flankers, single flanking lines, 10 flanking lines, rectangles and single perpendicular lines, varying the degree to which the vernier grouped with the flankers. Additionally, we used two different flanker widths (same width as and narrower than the target), again to vary target-flanker grouping. Our results show a clear effect of flankers: performance was much better when the vernier was presented alone compared to when it was presented with flankers. In the majority of flanker configurations, grouping between the target and the flankers determined the strength of interference, similar to the visual domain. However, in the same width rectangular flanker condition we found aberrant results. We discuss the results of our study in light of similarities and differences between vision and haptics and the interaction between different grouping principles. We conclude that in haptics, similar organization principles apply as in visual perception and argue that grouping and Gestalt are key organization principles not only of vision, but of the perceptual system in general.

  8. Asymmetric transfer of auditory perceptual learning

    Directory of Open Access Journals (Sweden)

    Sygal eAmitay

    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.

  9. 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 abstra...

  10. Authorship Attribution of Source Code

    Science.gov (United States)

    Tennyson, Matthew F.

    2013-01-01

    Authorship attribution of source code is the task of deciding who wrote a program, given its source code. Applications include software forensics, plagiarism detection, and determining software ownership. A number of methods for the authorship attribution of source code have been presented in the past. A review of those existing methods is…

  11. The neural basis of implicit perceptual sequence learning

    Directory of Open Access Journals (Sweden)

    Freja eGheysen

    2011-11-01

    Full Text Available The present fMRI study investigated the neural areas involved in implicit perceptual sequence learning. To obtain more insight in the functional contributions of the brain areas, we tracked both the behavioral and neural time course of the learning process, using a perceptual serial color matching task. Next, to investigate whether the neural time course was specific for perceptual information, imaging results were compared to the results of implicit motor sequence learning, previously investigated using an identical serial color matching task. Results indicated that implicit sequences can be acquired by at least two neural systems: the caudate nucleus and the hippocampus, having different operating principles. The caudate nucleus contributed to the implicit sequence learning process for perceptual as well as motor information in a similar and gradual way. The hippocampus, on the other hand, was engaged in a much faster learning process which was more pronounced for the motor compared to the perceptual task. Interestingly, the perceptual and motor learning process occurred on a comparable implicit level, suggesting that consciousness is not the main determinant factor dissociating the hippocampal from the caudate learning system. This study is not only the first to successfully and unambiguously compare brain activation between perceptual and motor levels of implicit sequence learning, it also provides new insights into the specific hippocampal and caudate learning function.

  12. Auditory-perceptual learning improves speech motor adaptation in children.

    Science.gov (United States)

    Shiller, Douglas M; Rochon, Marie-Lyne

    2014-08-01

    Auditory feedback plays an important role in children's speech development by providing the child with information about speech outcomes that is used to learn and fine-tune speech motor plans. The use of auditory feedback in speech motor learning has been extensively studied in adults by examining oral motor responses to manipulations of auditory feedback during speech production. Children are also capable of adapting speech motor patterns to perceived changes in auditory feedback; however, it is not known whether their capacity for motor learning is limited by immature auditory-perceptual abilities. Here, the link between speech perceptual ability and the capacity for motor learning was explored in two groups of 5- to 7-year-old children who underwent a period of auditory perceptual training followed by tests of speech motor adaptation to altered auditory feedback. One group received perceptual training on a speech acoustic property relevant to the motor task while a control group received perceptual training on an irrelevant speech contrast. Learned perceptual improvements led to an enhancement in speech motor adaptation (proportional to the perceptual change) only for the experimental group. The results indicate that children's ability to perceive relevant speech acoustic properties has a direct influence on their capacity for sensory-based speech motor adaptation.

  13. Attentional sets influence perceptual load effects, but not dilution effects.

    Science.gov (United States)

    Benoni, Hanna; Zivony, Alon; Tsal, Yehoshua

    2014-01-01

    Perceptual load theory [Lavie, N. (1995). Perceptual load as a necessary condition for selective attention. Journal of Experimental Psychology: Human Perception and Performance, 21, 451-468.; Lavie, N., & Tsal, Y. (1994) Perceptual load as a major determinant of the locus of selection in visual attention. Perception & Psychophysics, 56, 183-197.] proposes that interference from distractors can only be avoided in situations of high perceptual load. This theory has been supported by blocked design manipulations separating low load (when the target appears alone) and high load (when the target is embedded among neutral letters). Tsal and Benoni [(2010a). Diluting the burden of load: Perceptual load effects are simply dilution effects. Journal of Experimental Psychology: Human Perception and Performance, 36, 1645-1656.; Benoni, H., & Tsal, Y. (2010). Where have we gone wrong? Perceptual load does not affect selective attention. Vision Research, 50, 1292-1298.] have recently shown that these manipulations confound perceptual load with "dilution" (the mere presence of additional heterogeneous items in high-load situations). Theeuwes, Kramer, and Belopolsky [(2004). Attentional set interacts with perceptual load in visual search. Psychonomic Bulletin & Review, 11, 697-702.] independently questioned load theory by suggesting that attentional sets might also affect distractor interference. When high load and low load were intermixed, and participants could not prepare for the presentation that followed, both the low-load and high-load trials showed distractor interference. This result may also challenge the dilution account, which proposes a stimulus-driven mechanism. In the current study, we presented subjects with both fixed and mixed blocks, including a mix of dilution trials with low-load trials and with high-load trials. We thus separated the effect of dilution from load and tested the influence of attentional sets on each component. The results revealed that whereas

  14. Double Sided Watermark Embedding and Detection with Perceptual Analysis

    CERN Document Server

    Zhong, Jidong

    2007-01-01

    In our previous work, we introduced a double-sided technique that utilizes but not reject the host interference. Due to its nice property of utilizing but not rejecting the host interference, it has a big advantage over the host interference schemes in that the perceptual analysis can be easily implemented for our scheme to achieve the locally bounded maximum embedding strength. Thus, in this work, we detail how to implement the perceptual analysis in our double-sided schemes since the perceptual analysis is very important for improving the fidelity of watermarked contents. Through the extensive performance comparisons, we can further validate the performance advantage of our double-sided schemes.

  15. 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.

  16. Newborn hearing screening in the Campania region (Italy): early language and perceptual outcomes of infants with permanent hearing loss.

    Science.gov (United States)

    Marciano, E; Laria, C; Malesci, R; Iadicicco, P; Landolfi, E; Niri, C; Papa, C; Franzè, A; Auletta, G

    2013-12-01

    Hearing loss in children causes a deficit in early perceptive and language skills. The objective of this study was to evaluate early receptive and expressive language outcomes in children with hearing loss, identified by hearing screening, compared to the time of diagnosis. We studied 18 severely hearing impaired children who were divided into two groups according to the time of diagnosis. Evaluation of communicative language ability was carried out at 18 month of age using the "MacArthur Child Development Inventory" questionnaire, while evaluation of acoustic-perceptual abilities was assessed with the Genovese-Arslan protocol every three months following diagnosis. The linguistic communicative and acoustic-perceptual outcomes of hearing impaired children diagnosed before 6 months of age followed those expected for normally hearing children, with a trend of temporal progression of skills that were faster than those of children diagnosed after 6 months of age.

  17. 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.

  18. Perceptual skills of children with developmental coordination disorder.

    Science.gov (United States)

    Schoemaker, M M; van der Wees, M; Flapper, B; Verheij-Jansen, N; Scholten-Jaegers, S; Geuze, R H

    2001-03-01

    The aim of this study was to investigate whether children with a Developmental Coordination Disorder (DCD) experience problems in the processing of visual, proprioceptive or tactile information. Different aspects of visual perception were tested with the Developmental Test of Visual Perception (DTVP-2), tactile perception was assessed with the Tactual Performance Test (TPT), and a manual pointing task was employed to measure the ability to use visual and proprioceptive information in goal-directed movements. Nineteen children with DCD and nineteen age and sex-matched controls participated in this study. Differences between groups were most pronounced in the subtests measuring visual-motor integration of the DTVP-2, and in two subtests measuring visual perception (visual closure and position in space). On average the children with DCD performed slightly below the norm for tactile perception, with only three children failing the norm. On the manual pointing task, children with DCD made inconsistent responses towards the targets in all three conditions (visual, visual-proprioceptive and proprioceptive condition). No significant differences between groups were found for absolute error. Inspection of the individual data revealed that only two children failed on the majority of perceptual tasks in the three modalities. Across tasks, no consistent pattern of deficits appeared, illustrating the heterogeneity of the problems of children with DCD.

  19. Thin slices of child personality: Perceptual, situational, and behavioral contributions.

    Science.gov (United States)

    Tackett, Jennifer L; Herzhoff, Kathrin; Kushner, Shauna C; Rule, Nicholas

    2016-01-01

    The present study examined whether thin-slice ratings of child personality serve as a resource-efficient and theoretically valid measurement of child personality traits. We extended theoretical work on the observability, perceptual accuracy, and situational consistency of childhood personality traits by examining intersource and interjudge agreement, cross-situational consistency, and convergent, divergent, and predictive validity of thin-slice ratings. Forty-five unacquainted independent coders rated 326 children's (ages 8-12) personality in 1 of 15 thin-slice behavioral scenarios (i.e., 3 raters per slice, for over 14,000 independent thin-slice ratings). Mothers, fathers, and children rated children's personality, psychopathology, and competence. We found robust evidence for correlations between thin-slice and mother/father ratings of child personality, within- and across-task consistency of thin-slice ratings, and convergent and divergent validity with psychopathology and competence. Surprisingly, thin-slice ratings were more consistent across situations in this child sample than previously found for adults. Taken together, these results suggest that thin slices are a valid and reliable measure to assess child personality, offering a useful method of measurement beyond questionnaires, helping to address novel questions of personality perception and consistency in childhood.

  20. Few juvenile auditory perceptual skills correlate with adult performance.

    Science.gov (United States)

    Sarro, Emma C; Sanes, Dan H

    2014-02-01

    Measures of human mental development suggest that behavioral skills displayed during early life can predict an individual's subsequent cognitive performance. Support for this draws from longitudinal studies that reveal compelling within-subject correlations during childhood. If this idea applies across the life span, then correlations in performance should persist into adulthood. Here, we address this prediction in juvenile and adult gerbils by evaluating within-subject measures of auditory learning and perception. Animals were trained and tested as juveniles on either an amplitude modulation (AM) or a frequency modulation (FM) detection task. Measures of learning and perception obtained from juveniles were then compared to similar measures obtained when each subject was tested in adulthood on either the same task or the untrained task. For animals trained and tested on the AM detection task as juveniles and adults, there was no correlation between juvenile and adult learning metrics, or perceptual sensitivity. For animals trained and tested on FM detection as juveniles, we observed a significant relationship to their adult performance. Juveniles that performed the best on FM detection were the poorest at AM detection, and the best at FM detection, when tested as adults. Thus, across-age correlations for sensory and cognitive measures, obtained during development and in adulthood, depend heavily on the specific type of developmental experience and the outcome measure.

  1. 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...

  2. Can human eyes prevent perceptual narrowing for monkey faces in human infants?

    Science.gov (United States)

    Damon, Fabrice; Bayet, Laurie; Quinn, Paul C; Hillairet de Boisferon, Anne; Méary, David; Dupierrix, Eve; Lee, Kang; Pascalis, Olivier

    2015-07-01

    Perceptual narrowing has been observed in human infants for monkey faces: 6-month-olds can discriminate between them, whereas older infants from 9 months of age display difficulty discriminating between them. The difficulty infants from 9 months have processing monkey faces has not been clearly identified. It could be due to the structural characteristics of monkey faces, particularly the key facial features that differ from human faces. The current study aimed to investigate whether the information conveyed by the eyes is of importance. We examined whether the presence of Caucasian human eyes in monkey faces allows recognition to be maintained in 6-month-olds and facilitates recognition in 9- and 12-month-olds. Our results revealed that the presence of human eyes in monkey faces maintains recognition for those faces at 6 months of age and partially facilitates recognition of those faces at 9 months of age, but not at 12 months of age. The findings are interpreted in the context of perceptual narrowing and suggest that the attenuation of processing of other-species faces is not reversed by the presence of human eyes.

  3. Cultural differences in perceptual reorganization in US and Piraha adults.

    Directory of Open Access Journals (Sweden)

    Jennifer M D Yoon

    Full Text Available Visual illusions and other perceptual phenomena can be used as tools to uncover the otherwise hidden constructive processes that give rise to perception. Although many perceptual processes are assumed to be universal, variable susceptibility to certain illusions and perceptual effects across populations suggests a role for factors that vary culturally. One striking phenomenon is seen with two-tone images-photos reduced to two tones: black and white. Deficient recognition is observed in young children under conditions that trigger automatic recognition in adults. Here we show a similar lack of cue-triggered perceptual reorganization in the Pirahã, a hunter-gatherer tribe with limited exposure to modern visual media, suggesting such recognition is experience- and culture-specific.

  4. Perceptual discrimination in fear generalization: Mechanistic and clinical implications.

    Science.gov (United States)

    Struyf, Dieter; Zaman, Jonas; Vervliet, Bram; Van Diest, Ilse

    2015-12-01

    For almost a century, Pavlovian conditioning is the imperative experimental paradigm to investigate the development and generalization of fear. However, despite the rich research tradition, the conceptualization of fear generalization has remained somewhat ambiguous. In this selective review, we focus explicitly on some challenges with the current operationalization of fear generalization and their impact on the ability to make inferences on its clinical potential and underlying processes. The main conclusion is that, despite the strong evidence that learning influences perception, current research has largely neglected the role of perceptual discriminability and its plasticity in fear generalization. We propose an alternative operationalization of generalization, where the essence is that Pavlovian conditioning itself influences the breadth of fear generalization via learning-related changes in perceptual discriminability. Hence a conceptualization of fear generalization is incomplete without an in-depth analysis of processes of perceptual discriminability. Furthermore, this highlights perceptual learning and discriminability as important future targets for pre-clinical and clinical research.

  5. Role and Development of Perceptual Skills in Medical Education

    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. (2010, May). Role and Development of Perceptual Skills in Medical Education. The Scandinavian Workshop on Applied Eye-Tracking (SWAET), Lund, Sweden.

  6. Selective target processing: perceptual load or distractor salience?

    Science.gov (United States)

    Eltiti, Stacy; Wallace, Denise; Fox, Elaine

    2005-07-01

    Perceptual load theory (Lavie, 1995) states that participants cannot engage in focused attention when shown displays containing a low perceptual load, because attentional resources are not exhausted, whereas in high-load displays attention is always focused, because attentional resources are exhausted. An alternative "salience" hypothesis holds that the salience of distractors and not perceptual load per se determines selective attention. Three experiments were conducted to investigate the influence that target and distractor onsets and offsets have on selective processing in a standard interference task. Perceptual load theory predicts that, regardless of target or distractor presentation (onset or offset), interference from ignored distractors should occur in low-load displays only. In contrast, the salience hypothesis predicts that interference should occur when the distractor appears as an onset and would occur for distractor offsets only when the target was also an offset. Interference may even occur in highload displays if the distractor is more salient. The results supported the salience hypothesis.

  7. Linguistic and perceptual processing of communicative cues in Asperger Syndrome

    OpenAIRE

    Saalasti, Satu

    2012-01-01

    Asperger Syndrome (AS) belongs to autism spectrum disorders where both verbal and non-verbal communication difficulties are at the core of the impairment. Social communication requires a complex use of affective, linguistic-cognitive and perceptual processes. In the four studies included in the current thesis, some of the linguistic and perceptual factors that are important for face-to-face communication were studied using behavioural methods. In all four studies the results obtained from ind...

  8. Aging, Brain Size, and IQ.

    Science.gov (United States)

    Bigler, Erin D.; And Others

    1995-01-01

    Whether cross-sectional rates of decline for brain volume and the Performance Intellectual Quotient of the Wechsler Adult Intelligence Scale-Revised were equivalent over the years 16 to 65 was studied with 196 volunteers. Results indicate remarkably similar rates of decline in perceptual-motor functions and aging brain volume loss. (SLD)

  9. Success attributions and more: multidimensional extensions of the sexual attribution bias to failure attributions, social emotions, and the desire for social interaction.

    Science.gov (United States)

    Agthe, Maria; Spörrle, Matthias; Försterling, Friedrich

    2008-12-01

    According to the recently discovered sexual attribution bias (SAB), young adults attribute the success of same-aged, same-sex attractive stimulus persons in a more derogative way than the success of less attractive same-sex persons, whereas this pattern is reversed for members of the opposite sex. Because this bias has so far only been investigated with respect to attributions in success scenarios, two studies examined its potential transferability to other psychological variables and settings: Study 1 (N = 419) demonstrated analogous biases for emotions and the desire for social interaction, and Study 2 (N = 509) revealed that the SAB can also be extended to failure scenarios.

  10. Automatic imitation? Imitative compatibility affects responses at high perceptual load.

    Science.gov (United States)

    Catmur, Caroline

    2016-04-01

    Imitation involves matching the visual representation of another's action onto the observer's own motor program for that action. However, there has been some debate regarding the extent to which imitation is "automatic"-that is, occurs without attention. Participants performed a perceptual load task in which images of finger movements were presented as distractors. Responses to target letter stimuli were performed via finger movements that could be imitatively compatible (requiring the same finger movement) or incompatible with the distractor movements: In this common stimulus-response compatibility manipulation, the stimulus set comprises images of the response movements, producing an imitative compatibility effect. Attention to the distractor movements was manipulated by altering perceptual load through increasing the number of nontarget letter stimuli. If imitation requires attention, then at high perceptual load, imitative compatibility should not affect response times. In contrast, imitative compatibility influenced response times at high perceptual load, demonstrating that distractor movements were processed. However, the compatibility effect was reversed, suggesting that longer response times at high perceptual load tap into an inhibitory stage of distractor movement processing. A follow-up experiment manipulating temporal delay between targets and distractor movements supported this explanation. Further experiments confirmed that nonmovement distractor stimuli in the same configuration produced standard perceptual load effects and that results were not solely due to effector compatibility. These data suggest that imitation can occur without attention. (PsycINFO Database Record

  11. 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

  12. Perceptual Load Affects Eyewitness Accuracy & Susceptibility to Leading Questions

    Directory of Open Access Journals (Sweden)

    Gillian Murphy

    2016-08-01

    Full Text Available 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.

  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 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.

  15. 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.

  16. Neural Variability Quenching Predicts Individual Perceptual Abilities.

    Science.gov (United States)

    Arazi, Ayelet; Censor, Nitzan; Dinstein, Ilan

    2017-01-04

    Neural activity during repeated presentations of a sensory stimulus exhibits considerable trial-by-trial variability. Previous studies have reported that trial-by-trial neural variability is reduced (quenched) by the presentation of a stimulus. However, the functional significance and behavioral relevance of variability quenching and the potential physiological mechanisms that may drive it have been studied only rarely. Here, we recorded neural activity with EEG as subjects performed a two-interval forced-choice contrast discrimination task. Trial-by-trial neural variability was quenched by ∼40% after the presentation of the stimulus relative to the variability apparent before stimulus presentation, yet there were large differences in the magnitude of variability quenching across subjects. Individual magnitudes of quenching predicted individual discrimination capabilities such that subjects who exhibited larger quenching had smaller contrast discrimination thresholds and steeper psychometric function slopes. Furthermore, the magnitude of variability quenching was strongly correlated with a reduction in broadband EEG power after stimulus presentation. Our results suggest that neural variability quenching is achieved by reducing the amplitude of broadband neural oscillations after sensory input, which yields relatively more reproducible cortical activity across trials and enables superior perceptual abilities in individuals who quench more.

  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.

  18. Adaptation to direction statistics modulates perceptual discrimination.

    Science.gov (United States)

    Price, Nicholas S C; Prescott, Danielle L

    2012-06-22

    Perception depends on the relative activity of populations of sensory neurons with a range of tunings and response gains. Each neuron's tuning and gain are malleable and can be modified by sustained exposure to an adapting stimulus. Here, we used a combination of human psychophysical testing and models of neuronal population decoding to assess how rapid adaptation to moving stimuli might change neuronal tuning and thereby modulate direction perception. Using a novel motion stimulus in which the direction changed every 10 ms, we demonstrated that 1,500 ms of adaptation to a distribution of directions was capable of modifying human psychophysical direction discrimination performance. Consistent with previous reports, we found perceptual repulsion following adaptation to a single direction. Notably, compared with a uniform adaptation condition in which all motion directions were equiprobable, discrimination was impaired after adaptation to a stimulus comprising only directions ± 30-60° from the discrimination boundary and enhanced after adaptation to the complementary range of directions. Thus, stimulus distributions can be selectively chosen to either impair or improve discrimination performance through adaptation. A neuronal population decoding model incorporating adaptation-induced repulsive shifts in direction tuning curves can account for most aspects of our psychophysical data; however, changes in neuronal gain are sufficient to account for all aspects of our psychophysical data.

  19. An Electrophysiological Index of Perceptual Goodness

    Science.gov (United States)

    Makin, Alexis D.J.; Wright, Damien; Rampone, Giulia; Palumbo, Letizia; Guest, Martin; Sheehan, Rhiannon; Cleaver, Helen; Bertamini, Marco

    2016-01-01

    A traditional line of work starting with the Gestalt school has shown that patterns vary in strength and salience; a difference in “Perceptual goodness.” The Holographic weight of evidence model quantifies goodness of visual regularities. The key formula states that W = E/N, where E is number of holographic identities in a pattern and N is number of elements. We tested whether W predicts the amplitude of the neural response to regularity in an extrastriate symmetry-sensitive network. We recorded an Event Related Potential (ERP) generated by symmetry called the Sustained Posterior Negativity (SPN). First, we reanalyzed the published work and found that W explained most variance in SPN amplitude. Then in four new studies, we confirmed specific predictions of the holographic model regarding 1) the differential effects of numerosity on reflection and repetition, 2) the similarity between reflection and Glass patterns, 3) multiple symmetries, and 4) symmetry and anti-symmetry. In all cases, the holographic approach predicted SPN amplitude remarkably well; particularly in an early window around 300–400 ms post stimulus onset. Although the holographic model was not conceived as a model of neural processing, it captures many details of the brain response to symmetry. PMID:27702812

  20. 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.

  1. A perceptual space of local image statistics.

    Science.gov (United States)

    Victor, Jonathan D; Thengone, Daniel J; Rizvi, Syed M; Conte, Mary M

    2015-12-01

    Local image statistics are important for visual analysis of textures, surfaces, and form. There are many kinds of local statistics, including those that capture luminance distributions, spatial contrast, oriented segments, and corners. While sensitivity to each of these kinds of statistics have been well-studied, much less is known about visual processing when multiple kinds of statistics are relevant, in large part because the dimensionality of the problem is high and different kinds of statistics interact. To approach this problem, we focused on binary images on a square lattice - a reduced set of stimuli which nevertheless taps many kinds of local statistics. In this 10-parameter space, we determined psychophysical thresholds to each kind of statistic (16 observers) and all of their pairwise combinations (4 observers). Sensitivities and isodiscrimination contours were consistent across observers. Isodiscrimination contours were elliptical, implying a quadratic interaction rule, which in turn determined ellipsoidal isodiscrimination surfaces in the full 10-dimensional space, and made predictions for sensitivities to complex combinations of statistics. These predictions, including the prediction of a combination of statistics that was metameric to random, were verified experimentally. Finally, check size had only a mild effect on sensitivities over the range from 2.8 to 14min, but sensitivities to second- and higher-order statistics was substantially lower at 1.4min. In sum, local image statistics form a perceptual space that is highly stereotyped across observers, in which different kinds of statistics interact according to simple rules.

  2. Perceptual Depth Quality in Distorted Stereoscopic Images.

    Science.gov (United States)

    Wang, Jiheng; Wang, Shiqi; Ma, Kede; Wang, Zhou

    2017-03-01

    Subjective and objective measurement of the perceptual quality of depth information in symmetrically and asymmetrically distorted stereoscopic images is a fundamentally important issue in stereoscopic 3D imaging that has not been deeply investigated. Here, we first carry out a subjective test following the traditional absolute category rating protocol widely used in general image quality assessment research. We find this approach problematic, because monocular cues and the spatial quality of images have strong impact on the depth quality scores given by subjects, making it difficult to single out the actual contributions of stereoscopic cues in depth perception. To overcome this problem, we carry out a novel subjective study where depth effect is synthesized at different depth levels before various types and levels of symmetric and asymmetric distortions are applied. Instead of following the traditional approach, we ask subjects to identify and label depth polarizations, and a depth perception difficulty index (DPDI) is developed based on the percentage of correct and incorrect subject judgements. We find this approach highly effective at quantifying depth perception induced by stereo cues and observe a number of interesting effects regarding image content dependency, distortion-type dependence, and the impact of symmetric versus asymmetric distortions. Furthermore, we propose a novel computational model for DPDI prediction. Our results show that the proposed model, without explicitly identifying image distortion types, leads to highly promising DPDI prediction performance. We believe that these are useful steps toward building a comprehensive understanding on 3D quality-of-experience of stereoscopic images.

  3. Visual perceptual load induces inattentional deafness.

    Science.gov (United States)

    Macdonald, James S P; Lavie, Nilli

    2011-08-01

    In this article, we establish a new phenomenon of "inattentional deafness" and highlight the level of load on visual attention as a critical determinant of this phenomenon. In three experiments, we modified an inattentional blindness paradigm to assess inattentional deafness. Participants made either a low- or high-load visual discrimination concerning a cross shape (respectively, a discrimination of line color or of line length with a subtle length difference). A brief pure tone was presented simultaneously with the visual task display on a final trial. Failures to notice the presence of this tone (i.e., inattentional deafness) reached a rate of 79% in the high-visual-load condition, significantly more than in the low-load condition. These findings establish the phenomenon of inattentional deafness under visual load, thereby extending the load theory of attention (e.g., Lavie, Journal of Experimental Psychology. Human Perception and Performance, 25, 596-616, 1995) to address the cross-modal effects of visual perceptual load.

  4. Neural Correlates of Multisensory Perceptual Learning

    Science.gov (United States)

    Powers, Albert R.; Hevey, Matthew A.; Wallace, Mark T.

    2012-01-01

    The brain’s ability to bind incoming auditory and visual stimuli depends critically on the temporal structure of this information. Specifically, there exists a temporal window of audiovisual integration within which stimuli are highly likely to be perceived as part of the same environmental event. Several studies have described the temporal bounds of this window, but few have investigated its malleability. Recently, our laboratory has demonstrated that a perceptual training paradigm is capable of eliciting a 40% narrowing in the width of this window that is stable for at least one week after cessation of training. In the current study we sought to reveal the neural substrates of these changes. Eleven human subjects completed an audiovisual simultaneity judgment training paradigm, immediately before and after which they performed the same task during an event-related 3T fMRI session. The posterior superior temporal sulcus (pSTS) and areas of auditory and visual cortex exhibited robust BOLD decreases following training, and resting state and effective connectivity analyses revealed significant increases in coupling among these cortices after training. These results provide the first evidence of the neural correlates underlying changes in multisensory temporal binding and that likely represent the substrate for a multisensory temporal binding window. PMID:22553032

  5. The influence of imagery vividness on cognitive and perceptual cues in circular auditorily-induced vection

    Directory of Open Access Journals (Sweden)

    Aleksander eVäljamäe

    2014-12-01

    Full Text Available In the absence of other congruent multisensory motion cues, sound contribution to illusions of self-motion (vection is relatively weak and often attributed to purely cognitive, top-down processes. The present study addressed the influence of cognitive and perceptual factors in the experience of circular, yaw auditorily-induced vection (AIV, focusing on participants’ imagery vividness scores. We used different rotating sound sources (acoustic landmark vs. movable types and their filtered versions that provided different binaural cues (interaural time or level differences, ITD vs. ILD when delivering via loudspeaker array. The significant differences in circular vection intensity showed that 1 AIV was stronger for rotating sound fields containing auditory landmarks as compared to movable sound objects; 2 ITD based acoustic cues were more instrumental than ILD based ones for horizontal AIV; and 3 individual differences in imagery vividness significantly influenced the effects of contextual and perceptual cues. While participants with high scores of kinesthetic and visual imagery were helped by vection ``rich cues, i.e. acoustic landmarks and ITD cues, the participants from the low-vivid imagery group did not benefit from these cues automatically. Only when specifically asked to use their imagination intentionally did these external cues start influencing vection sensation in similar way to high-vivid imagers. These findings are in line with the recent fMRI work which suggested that high-vivid imagers employ automatic, almost unconscious mechanisms in imagery generation, while low-vivid imagers rely on more schematic and conscious framework. Consequently, our results provide an additional insight into the interaction between perceptual and contextual cues when experiencing purely auditorily or multisensorily induced vection.

  6. Assessment of cerebral visual impairment with the L94 visual perceptual battery: clinical value and correlation with MRI findings.

    Science.gov (United States)

    Ortibus, E; Lagae, L; Casteels, I; Demaerel, P; Stiers, P

    2009-03-01

    In this article we describe visual perceptual abilities of a clinical population, referred for visual problems to our multidisciplinary team and assessed with the five computer tasks from the L94 visual perceptual battery. Clinical and neuroimaging findings were correlated with the findings on this task battery. Seventy children (35 males, 35 females) constituted our cohort. Age ranged from 4 to 20 years (mean 7y [SD 3y]). Forty children were born before 37 weeks gestational age. Thirty-six children had cerebral palsy (CP), of whom 24 had spastic diplegia, five had spastic hemiplegia, and four had spastic quadriplegia. Three children had ataxic CP. Perceptual visual impairment (PVI) was established in comparison to the performance age obtained on non-verbal intelligence subtests, instead of chronological age. Our results suggest that children with a history of preterm birth and a clinical CP picture are most at risk for a specific PVI. Correlations among other clinical variables did not define a clinical subgroup more at risk. Children with periventricular leucomalacia were almost equally represented in both PVI and non-PVI groups. Normal magnetic resonance imaging did not exclude the presence of PVI. In these children, however, we found another impairment profile, more in favour of dorsal stream impairment.

  7. 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.

  8. Low level perceptual, not attentional, processes modulate distractor interference in high perceptual Load displays: evidence from neglect/extinction

    Directory of Open Access Journals (Sweden)

    Carmel eMevorach

    2014-01-01

    Full Text Available According to perceptual load theory (Lavie, 2005 distractor interference is determined by the availability of attentional resources. If target processing does not exhaust resources (with low perceptual load distractor processing will take place resulting in interference with a primary task; however when target processing uses-up attentional capacity (with high perceptual load interference can be avoided. An alternative account (Tsal & Benoni, 2010 suggests that perceptual load effects can be based on distractor dilution by the mere presence of additional neutral items in high load displays so that the effect is not driven by the amount of attention resources required for target processing. Here we tested whether patients with unilateral neglect or extinction would show dilution effects from neutral items in their contralesional (neglected/extinguished field, even though these items do not impose increased perceptual load on the target and at the same time attract reduced attentional resources compared to stimuli in the ipsilesional field. Thus, such items do not affect the amount of attention resources available for distractor processing. We found that contralesional neutral elements can eliminate distractor interference as strongly as centrally presented ones in neglect/extinction patients, despite contralesional items being less well attended. The data are consistent with an account in terms of perceptual dilution of distracters rather than available resources for distractor processing. We conclude that distractor dilution can underlie the elimination of distractor interference in visual displays.

  9. Low level perceptual, not attentional, processes modulate distractor interference in high perceptual load displays: evidence from neglect/extinction.

    Science.gov (United States)

    Mevorach, Carmel; Tsal, Yehoshua; Humphreys, Glyn W

    2014-01-10

    According to perceptual load theory (Lavie, 2005) distractor interference is determined by the availability of attentional resources. If target processing does not exhaust resources (with low perceptual load) distractor processing will take place resulting in interference with a primary task; however, when target processing uses-up attentional capacity (with high perceptual load) interference can be avoided. An alternative account (Tsal and Benoni, 2010a) suggests that perceptual load effects can be based on distractor dilution by the mere presence of additional neutral items in high-load displays so that the effect is not driven by the amount of attention resources required for target processing. Here we tested whether patients with unilateral neglect or extinction would show dilution effects from neutral items in their contralesional (neglected/extinguished) field, even though these items do not impose increased perceptual load on the target and at the same time attract reduced attentional resources compared to stimuli in the ipsilesional field. Thus, such items do not affect the amount of attention resources available for distractor processing. We found that contralesional neutral elements can eliminate distractor interference as strongly as centrally presented ones in neglect/extinction patients, despite contralesional items being less well attended. The data are consistent with an account in terms of perceptual dilution of distracters rather than available resources for distractor processing. We conclude that distractor dilution can underlie the elimination of distractor interference in visual displays.

  10. Attribution of blame in incest.

    Science.gov (United States)

    Jackson, T L; Ferguson, W P

    1983-06-01

    This study was designed to identify the empirical structure of attitudes relating to attribution of blame in incest. A second purpose was to determine how variables such as gender, physically abused status, and sexually abused status influence the attribution of blame in incest. A sample of 201 male and 211 female college students was administered the Jackson Incest Blame Scale. Four factors emerged from the factor analysis of the total sample supporting the hypothesis that attribution of blame in incest is a multidimensional construct including victim, offender, situational, and societal factors. A difference in the level of victim blame was found between male and female samples. Results are discussed with regard to their implications for further research and training. Other potential uses of the Jackson Incest Blame Scale are suggested.

  11. Subspace clustering through attribute clustering

    Institute of Scientific and Technical Information of China (English)

    Kun NIU; Shubo ZHANG; Junliang CHEN

    2008-01-01

    Many recently proposed subspace clustering methods suffer from two severe problems. First, the algorithms typically scale exponentially with the data dimensionality or the subspace dimensionality of clusters. Second, the clustering results are often sensitive to input parameters. In this paper, a fast algorithm of subspace clustering using attribute clustering is proposed to over-come these limitations. This algorithm first filters out redundant attributes by computing the Gini coefficient. To evaluate the correlation of every two non-redundant attributes, the relation matrix of non-redundant attributes is constructed based on the relation function of two dimensional united Gini coefficients. After applying an overlapping clustering algorithm on the relation matrix, the candidate of all interesting subspaces is achieved. Finally, all subspace clusters can be derived by clustering on interesting subspaces. Experiments on both synthesis and real datasets show that the new algorithm not only achieves a significant gain of runtime and quality to find subspace clusters, but also is insensitive to input parameters.

  12. SOA: A Quality Attribute Perspective

    Science.gov (United States)

    2011-06-23

    JMS) – CORBA … • Infrastructure services available to service providers and/or service consumers to perform common tasks or satisfy QoS requirements...Services is one technology for SOA implementation SOA and Quality Attributes SOA WS* Web Services CORBA REST Services and POX Key Class Realization

  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. 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 tech...

  15. 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...

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

    Science.gov (United States)

    Zhou, Peiyun; Christianson, Kiel

    2016-01-01

    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.

  17. 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.

  18. Perceptual Biases in Relation to Paranormal and Conspiracy Beliefs.

    Science.gov (United States)

    van Elk, Michiel

    2015-01-01

    Previous studies have shown that one's prior beliefs have a strong effect on perceptual decision-making and attentional processing. The present study extends these findings by investigating how individual differences in paranormal and conspiracy beliefs are related to perceptual and attentional biases. Two field studies were conducted in which visitors of a paranormal conducted a perceptual decision making task (i.e. the face/house categorization task; Experiment 1) or a visual attention task (i.e. the global/local processing task; Experiment 2). In the first experiment it was found that skeptics compared to believers more often incorrectly categorized ambiguous face stimuli as representing a house, indicating that disbelief rather than belief in the paranormal is driving the bias observed for the categorization of ambiguous stimuli. In the second experiment, it was found that skeptics showed a classical 'global-to-local' interference effect, whereas believers in conspiracy theories were characterized by a stronger 'local-to-global interference effect'. The present study shows that individual differences in paranormal and conspiracy beliefs are associated with perceptual and attentional biases, thereby extending the growing body of work in this field indicating effects of cultural learning on basic perceptual processes.

  19. Acoustic and perceptual similarity of Japanese and American English vowels.

    Science.gov (United States)

    Nishi, Kanae; Strange, Winifred; Akahane-Yamada, Reiko; Kubo, Rieko; Trent-Brown, Sonja A

    2008-07-01

    Acoustic and perceptual similarities between Japanese and American English (AE) vowels were investigated in two studies. In study 1, a series of discriminant analyses were performed to determine acoustic similarities between Japanese and AE vowels, each spoken by four native male speakers using F1, F2, and vocalic duration as input parameters. In study 2, the Japanese vowels were presented to native AE listeners in a perceptual assimilation task, in which the listeners categorized each Japanese vowel token as most similar to an AE category and rated its goodness as an exemplar of the chosen AE category. Results showed that the majority of AE listeners assimilated all Japanese vowels into long AE categories, apparently ignoring temporal differences between 1- and 2-mora Japanese vowels. In addition, not all perceptual assimilation patterns reflected context-specific spectral similarity patterns established by discriminant analysis. It was hypothesized that this incongruity between acoustic and perceptual similarity may be due to differences in distributional characteristics of native and non-native vowel categories that affect the listeners' perceptual judgments.

  20. Perceptual learning reconfigures the effects of visual adaptation.

    Science.gov (United States)

    McGovern, David P; Roach, Neil W; Webb, Ben S

    2012-09-26

    Our sensory experiences over a range of different timescales shape our perception of the environment. Two particularly striking short-term forms of plasticity with manifestly different time courses and perceptual consequences are those caused by visual adaptation and perceptual learning. Although conventionally treated as distinct forms of experience-dependent plasticity, their neural mechanisms and perceptual consequences have become increasingly blurred, raising the possibility that they might interact. To optimize our chances of finding a functionally meaningful interaction between learning and adaptation, we examined in humans the perceptual consequences of learning a fine discrimination task while adapting the neurons that carry most information for performing this task. Learning improved discriminative accuracy to a level that ultimately surpassed that in an unadapted state. This remarkable improvement came at a price: adapting directions that before learning had little effect elevated discrimination thresholds afterward. The improvements in discriminative accuracy grew quickly and surpassed unadapted levels within the first few training sessions, whereas the deterioration in discriminative accuracy had a different time course. This learned reconfiguration of adapted discriminative accuracy occurred without a concomitant change to the characteristic perceptual biases induced by adaptation, suggesting that the system was still in an adapted state. Our results point to a functionally meaningful push-pull interaction between learning and adaptation in which a gain in sensitivity in one adapted state is balanced by a loss of sensitivity in other adapted states.

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

    Science.gov (United States)

    Jepma, Marieke; Verdonschot, Rinus G; van Steenbergen, Henk; Rombouts, Serge A R B; Nieuwenhuis, Sander

    2012-01-01

    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 (1) the induction of perceptual curiosity, through the presentation of ambiguous visual input, activated the anterior insula and anterior cingulate cortex (ACC), brain regions sensitive to conflict and arousal; (2) the relief of perceptual curiosity, through visual disambiguation, activated regions of the striatum that have been related to reward processing; and (3) 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.

  2. Perceptual averaging in individuals with Autism Spectrum Disorder

    Directory of Open Access Journals (Sweden)

    Jennifer Elise Corbett

    2016-11-01

    Full Text Available There is mounting evidence that observers rely on statistical summaries of visual information to maintain stable and coherent perception. Sensitivity to the mean (or other prototypical value of a visual feature (e.g., mean size appears to be a pervasive process in human visual perception. Previous studies in individuals diagnosed with Autism Spectrum Disorder (ASD have uncovered characteristic patterns of visual processing that suggest they may rely more on enhanced local representations of individual objects instead of computing such perceptual averages. To further explore the fundamental nature of abstract statistical representation in visual perception, we investigated perceptual averaging of mean size in a group of 12 high-functioning individuals diagnosed with ASD using simplified versions of two identification and adaptation tasks that elicited characteristic perceptual averaging effects in a control group of neurotypical participants. In Experiment 1, participants performed with above chance accuracy in recalling the mean size of a set of circles (mean task despite poor accuracy in recalling individual circle sizes (member task. In Experiment 2, their judgments of single circle size were biased by mean size adaptation. Overall, these results suggest that individuals with ASD perceptually average information about sets of objects in the surrounding environment. Our results underscore the fundamental nature of perceptual averaging in vision, and further our understanding of how autistic individuals make sense of the external environment.

  3. Perceptual Biases in Relation to Paranormal and Conspiracy Beliefs.

    Directory of Open Access Journals (Sweden)

    Michiel van Elk

    Full Text Available Previous studies have shown that one's prior beliefs have a strong effect on perceptual decision-making and attentional processing. The present study extends these findings by investigating how individual differences in paranormal and conspiracy beliefs are related to perceptual and attentional biases. Two field studies were conducted in which visitors of a paranormal conducted a perceptual decision making task (i.e. the face/house categorization task; Experiment 1 or a visual attention task (i.e. the global/local processing task; Experiment 2. In the first experiment it was found that skeptics compared to believers more often incorrectly categorized ambiguous face stimuli as representing a house, indicating that disbelief rather than belief in the paranormal is driving the bias observed for the categorization of ambiguous stimuli. In the second experiment, it was found that skeptics showed a classical 'global-to-local' interference effect, whereas believers in conspiracy theories were characterized by a stronger 'local-to-global interference effect'. The present study shows that individual differences in paranormal and conspiracy beliefs are associated with perceptual and attentional biases, thereby extending the growing body of work in this field indicating effects of cultural learning on basic perceptual processes.

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

    Directory of Open Access Journals (Sweden)

    Marieke eJepma

    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.

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

    Science.gov (United States)

    Jepma, Marieke; Verdonschot, Rinus G.; van Steenbergen, Henk; Rombouts, Serge A. R. B.; Nieuwenhuis, Sander

    2012-01-01

    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 (1) the induction of perceptual curiosity, through the presentation of ambiguous visual input, activated the anterior insula and anterior cingulate cortex (ACC), brain regions sensitive to conflict and arousal; (2) the relief of perceptual curiosity, through visual disambiguation, activated regions of the striatum that have been related to reward processing; and (3) 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. PMID:22347853

  6. 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

  7. 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.

  8. Organizational Attributes, Market Growth, and Product Innovation

    NARCIS (Netherlands)

    Song, Michael; Chen, Yan

    2014-01-01

    Extensive research has shown that organizational attributes affect product innovation. Extending this literature, this article delimits two general categories of organizational attributes and relates them to product innovation. Organizational attributes can be either control oriented or flexibility

  9. Probability shapes perceptual precision: A study in orientation estimation.

    Science.gov (United States)

    Jabar, Syaheed B; Anderson, Britt

    2015-12-01

    Probability is known to affect perceptual estimations, but an understanding of mechanisms is lacking. Moving beyond binary classification tasks, we had naive participants report the orientation of briefly viewed gratings where we systematically manipulated contingent probability. Participants rapidly developed faster and more precise estimations for high-probability tilts. The shapes of their error distributions, as indexed by a kurtosis measure, also showed a distortion from Gaussian. This kurtosis metric was robust, capturing probability effects that were graded, contextual, and varying as a function of stimulus orientation. Our data can be understood as a probability-induced reduction in the variability or "shape" of estimation errors, as would be expected if probability affects the perceptual representations. As probability manipulations are an implicit component of many endogenous cuing paradigms, changes at the perceptual level could account for changes in performance that might have traditionally been ascribed to "attention."

  10. A critical evaluation of two approaches to defining perceptual salience

    Directory of Open Access Journals (Sweden)

    Bethany MacLeod

    2015-01-01

    Full Text Available The notion of perceptual salience is frequently invoked as an explanatory factor in discussions of various linguistic phenomena, but the way salience is defined varies between studies. This paper provides a critical evaluation of two approaches to operationalizing perceptual salience that have been applied to studies of phonetic accommodation: the criteria-list approach and the experimental approach. The purpose is to provide a starting point for researchers interested in exploring the role of perceptual salience in linguistic patterns, such as phonetic accommodation. In addition, the paper aims to consider the nature of the information captured by the different approaches, to explore how these approaches might be best used, and to examine how they reflect changes in theorizing on linguistic variables more generally.

  11. Perceptual reasoning managed situation assessment and adaptive fusion processing

    Science.gov (United States)

    Kadar, Ivan

    2001-08-01

    A unified perceptual reasoning system framework for adaptive sensor fusion and situation assessment is presented. The concept and application of perception, the resultant system architecture and its candidate renditions using knowledge- based systems and associative memory are discussed. The perceptual reasoning system is shown to be a natural governing mechanism for extracting, associating and fusing information from multiple sources while adaptively controlling the Joint Director of Laboratories (JDL) Fusion Model processes for optimum fusion system performance. The unified modular system construct is shown to provide a formal framework to accommodate various implementation alternatives. The application of this architectural concept is illustrated for representative network centric surveillance system architecture. A target identification system using Dempster-Shafer declarations level fusion is used to demonstrate the benefits of the adaptive perceptual reasoning system and the iterative evidential reasoning method.

  12. Attribute-based analysis of hunters' lease preferences.

    Science.gov (United States)

    Hussain, Anwar; Munn, Ian A; Hudson, Darren; West, Ben

    2010-12-01

    Understanding of hunter preferences for hunting lease attributes is important to landowners because such knowledge provides key information for managing and marketing fee-hunting in order to maximize revenues. Premised on this insight, we used attribute based modeling to investigate how hunter preferences for potential leases were influenced by lease and hunter-specific attributes. A mail survey of Mississippi licensed hunters provided the necessary data. Estimation results based on McFadden conditional logit regression suggested that lease attributes including game diversity, lease location relative to hunter residence, lease size, lease duration and lease rate influenced willingness to pay for additional units of lease attributes. Depending on the specific levels of these attributes, WTP could vary as much as $5.70 per acre. Of the hunter-specific attributes, age and income significantly influenced hunter decision to buy a lease or opt for status quo. Results of this study should assist landowners in increasing financial returns from fee-hunting endeavors through appropriate changes to their hunting access policies and wildlife management activities in response to hunter preferences regarding lease attributes.

  13. 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.

  14. Motor impairments screened by the movement assessment battery for children-2 are related to the visual-perceptual deficits in children with developmental coordination disorder.

    Science.gov (United States)

    Cheng, Chih-Hsiu; Ju, Yan-Ying; Chang, Hsin-Wen; Chen, Chia-Ling; Pei, Yu-Cheng; Tseng, Kevin C; Cheng, Hsin-Yi Kathy

    2014-09-01

    This study was to examine to what extent the motor deficits of children with Developmental Coordination Disorder (DCD) verified by the Movement Assessment Battery for Children-2 (MABC-2) are linked to their visual-perceptual abilities. Seventeen children with DCD and seventeen typically developing children (TD) aged 5-10 years screened from a total of 250 children were recruited. The assessments included MABC-2, traditional test of visual perceptual skills (TVPS-R), and computerized test for sequential coupling of eye and hand as well as motion coherence. The results indicated that children with DCD scored lower than TD in MABC-2, and their total scores were highly correlated with manual dexterity component scores. DCD group also showed poor visual-perceptual abilities in various aspects. The visual discrimination and visual sequential memory from the TVPS-R, the sequential coupling of eye and hand, and the motion coherence demonstrated a moderate or strong correlation with the MABC-2 in the DCD rather than the TD group. It was concluded that the motor problems screened by MABC-2 were significantly related to the visual-perceptual deficits of children with DCD. MABC-2 is suggested to be a prescreening tool to identify the visual-perceptual related motor deficits.

  15. Constructing knowledge through perceptual processes in making craft-art

    Directory of Open Access Journals (Sweden)

    Milla Ojala

    2013-10-01

    Full Text Available The focus of the study is on the knowledge that is constructed through perceptual processes during craft making in the context of the Finnish Basic Education in the Arts (BEA system. Craft studies in the BEA are defined as craft-art. The research method used is the grounded theory. The data consists of seven interviews and participant observations. Participants in the study are adolescents who study craft-art in the BEA system in Visual Art School, Aimo in Hämeenlinna. The aim of the article is to present, define and reflect on the concepts, properties and dimensions concerning perceptual processes that are discovered in this stage of the study following grounded theory procedures. The perceptual processes are an essential means of constructing knowledge in craft-art. Consequently, one aim of the study is to discuss how these processes are connected to various types of knowledge. The perceptual processes are described by seven concepts: imitative, anticipative, evaluative, experimental, emotional, temporal and bodily perceptions. They indicate on a conceptual level the characteristic of knowledge constructed through perceptual processes in craft-art. Further, theconcepts have several properties that can vary dimensionally between two qualities. The properties are activity, function and position. The dimensions of the properties vary from active to passive, formal to informal and internal to external. In conclusion, the concepts can describe a large range of incidents in different situations. They also seem to describe well the practice of  craft-art and there are several connections with pre-existing concepts of knowledge.Keywords: Craft, Knowledge, Perceptual process, Basic Education in the Arts, Grounded Theory 

  16. 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.

  17. Recent improvements to Thor with emphasis on perceptual coding tools

    Science.gov (United States)

    Davies, Thomas; Bjøntegaard, Gisle; Fuldseth, Arild; Midtskogen, Steinar

    2016-09-01

    Thor supports a number of coding tools that have the potential to improve perceptual as well as objective quality. Synthetic reference frames may be used to support high frame rate applications in circumstances where encoders might typically transmit reduced frame rate content. Quantization matrices can be used to give improved visual quality by allocating bits more closely according to perceptual significance. Thor's Constrained Low Pass Loop Filter provides significant subjective benefit in removing coding artefacts such as ringing. Improved colour fidelity can also be obtained by leveraging luma information. This paper discusses developments in these tools and their objective and subjective performance.

  18. Effects of musicianship and experimental task on perceptual segmentation

    DEFF Research Database (Denmark)

    Hartmann, Martin; Lartillot, Olivier; Toiviainen, Petri

    2015-01-01

    The perceptual structure of music is a fundamental issue in music psychology that can be systematically addressed via computational models. This study estimated the contribution of spectral, rhythmic and tonal descriptors for prediction of perceptual segmentation across stimuli. In a real-time task...... important to predict segmentation by listeners. Our results suggest that musicians pay attention to more features than non-musicians, including more high-level structure interactions. Prediction of non-real-time annotations involved more features, particularly interactions thereof, suggesting high context...

  19. Perceptual distortions and deceptions: what computers can teach us

    Science.gov (United States)

    Nour, Matthew M.; Nour, Joseph M.

    2017-01-01

    The nature of perception has fascinated philosophers for centuries, and has more recently been the focus of research in psychology and neuroscience. Many psychiatric disorders are characterised by perceptual abnormalities, ranging from sensory distortions to illusions and hallucinations. The distinction between normal and abnormal perception is, however, hard to articulate. In this article we argue that the distinction between normal perception and abnormal perception is best seen as a quantitative one, resting on the degree to which the observer's prior expectations influence perceptual inference. We illustrate this point with an example taken from researchers at Google working on computer vision. PMID:28184316

  20. An Improved Scalar Costa Scheme Based on Watson Perceptual Model

    Institute of Scientific and Technical Information of China (English)

    QI Kai-yue; CHEN Jian-bo; ZHOU Yi

    2008-01-01

    An improved scalar Costa scheme (SCS) was proposed by using improved Watson perceptual model to adaptively decide quantization step size and scaling factor. The improved scheme equals to embed hiding data based on an actual image. In order to withstand amplitude scaling attack, the Watson perceptual model was redefined, and the improved scheme using the new definition can insure quantization step size in decoder that is proportional to amplitude scaling attack factor. The performance of the improved scheme outperforms that of SCS with fixed quantization step size. The improved scheme combines information theory and visual model.

  1. 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

  2. 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

  3. 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

  4. Effect Size Matters : The Role of Language Statistics and Perceptual Simulation in Conceptual Processing

    NARCIS (Netherlands)

    Louwerse, M.M.; Hutchinson, S; Tillman, R.N.

    2014-01-01

    The cognitive science literature increasingly demonstrates that perceptual representations are activated during conceptual processing. Such findings suggest that the debate on whether conceptual processing is predominantly symbolic or perceptual has been resolved. However, studies too frequently pro

  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. Cross-modal selective attention and perceptual load in autism spectrum disorder

    OpenAIRE

    Tillmann, J. E.

    2016-01-01

    This thesis investigated cross-modal selective attention in children and adolescents with Autism Spectrum Disorder (ASD) and typically developing (TD) individuals using the Load Theory of Selective Attention and Cognitive Control (Lavie, 1995). Perceptual load theory states that perception of irrelevant stimuli depends on the perceptual load of the task (the amount of task relevant information). At low levels of perceptual load, when finite perceptual capacity is not reached, remaining resour...

  7. Who are you expecting? Biases in face perception reveal prior expectations for sex and age.

    Science.gov (United States)

    Watson, Tamara Lea; Otsuka, Yumiko; Clifford, Colin Walter Giles

    2016-01-01

    A person's appearance contains a wealth of information, including indicators of their sex and age. Because first impressions can set the tone of subsequent relationships, it is crucial we form an accurate initial impression. Yet prior expectation can bias our decisions: Studies have reported biases to respond "male" when asked to report a person's sex from an image of their face and to place their age closer to their own. Perceptual expectation effects and cognitive response biases may both contribute to these inaccuracies. The current research used a Bayesian modeling approach to establish the perceptual biases involved when estimating the sex and age of an individual from their face. We demonstrate a perceptual bias for male and older faces evident under conditions of uncertainty. This suggests the well-established male bias is perceptual in origin and may be impervious to cognitive control. In comparison, the own age anchor effect is not operationalized at the perceptual level: The perceptual expectation is for a face of advanced age. Thus, distinct biases in the estimation of age operate at the perceptual and cognitive levels.

  8. Rich man, poor man: developmental differences in attributions and perceptions.

    Science.gov (United States)

    Sigelman, Carol K

    2012-11-01

    In an examination guided by cognitive developmental and attribution theory of how explanations of wealth and poverty and perceptions of rich and poor people change with age and are interrelated, 6-, 10-, and 14-year-olds (N=88) were asked for their causal attributions and trait judgments concerning a rich man and a poor man. First graders, like older children, perceived the rich man as more competent than the poor man. However, they had difficulty in explaining wealth and poverty, especially poverty, and their trait perceptions were associated primarily with their attributions of wealth to job status, education, and luck. Fifth and ninth graders more clearly attributed wealth and poverty to the equity factors of ability and effort and based their trait perceptions on these attributions. Although the use of structured attribution questions revealed more understanding among young children than previous studies have suggested, the findings suggest a shift with age in the underlying bases for differential evaluation of rich and poor people from a focus on good outcomes associated with wealth (a good education and job) to a focus on personal qualities responsible for wealth (ability and effort).

  9. The Development of Perceptual Grouping Biases in Infancy: A Japanese-English Cross-Linguistic Study

    Science.gov (United States)

    Yoshida, Katherine A.; Iversen, John R.; Patel, Aniruddh D.; Mazuka, Reiko; Nito, Hiromi; Gervain, Judit; Werker, Janet F.

    2010-01-01

    Perceptual grouping has traditionally been thought to be governed by innate, universal principles. However, recent work has found differences in Japanese and English speakers' non-linguistic perceptual grouping, implicating language in non-linguistic perceptual processes (Iversen, Patel, & Ohgushi, 2008). Two experiments test Japanese- and…

  10. On Perceptual Distortion Minimization and Nonlinear Least-Squares Frequency Estimation

    DEFF Research Database (Denmark)

    Christensen, Mads Græsbøll; Jensen, Søren Holdt

    2006-01-01

    In this paper, we present a framework for perceptual error minimization and sinusoidal frequency estimation based on a new perceptual distortion measure, and we state its optimal solution. Using this framework, we relate a number of well-known practical methods for perceptual sinusoidal parameter...

  11. Mississippi Perceptual Motor Symposium Proceedings (Jackson, April 20-21, 1973).

    Science.gov (United States)

    Carlson, Robert; And Others

    Presented are the proceedings of the Mississippi Perceptual-Motor Symposium, April 20-21, 1973. Included are papers on motor development, models for perceptual motor programming, children with minimal brain damage, effects of learning games or academic abilities, research on perceptual motor measures, and programs for motor development. (JB)

  12. First-Hand Accounts of Sensory Perceptual Experiences in Autism: A Qualitative Analysis.

    Science.gov (United States)

    Jones, Robert S. P.; Quigney, Ciara; Huws, Jaci C.

    2003-01-01

    Five first-hand Web page accounts of unusual sensory perceptual experiences written by persons with high-functioning autism were selected for qualitative analysis. Four core categories emerged: turbulent sensory perceptual experiences; coping mechanisms; enjoyable sensory perceptual experiences; and awareness of being different, suggesting they…

  13. Interrogative suggestibility and perceptual motor performance.

    Science.gov (United States)

    Gudjonsson, G H

    1984-04-01

    This study investigates the relationship between interrogative suggestibility, as measured by the Gudjonsson Suggestibility Scale, and Arrow-Dot scores. The tendency of subjects (25 men and 25 women, mean age 30.2 yr.) to alter their answers once interpersonal pressure had been applied correlated significantly with poor Arrow-Dot Ego functioning.

  14. 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.

  15. Perceptual Grouping Affects Pitch Judgments across Time and Frequency

    Science.gov (United States)

    Borchert, Elizabeth M. O.; Micheyl, Christophe; Oxenham, Andrew J.

    2011-01-01

    Pitch, the perceptual correlate of fundamental frequency (F0), plays an important role in speech, music, and animal vocalizations. Changes in F0 over time help define musical melodies and speech prosody, while comparisons of simultaneous F0 are important for musical harmony, and for segregating competing sound sources. This study compared…

  16. Identifying the dominating perceptual differences in headphone reproduction

    DEFF Research Database (Denmark)

    Volk, Christer Peter; Lavandier, Mathieu; Bech, Søren

    2016-01-01

    . A multidimensional scaling analysis revealed two dominating perceptual dimensions used by the listeners to differentiate the reproductions of the headphones. These dimensions were similar for the two musical excerpts. Objective metrics are proposed to describe them, leading to correlations ranging from 0.89 to 0...

  17. Perceptual Classification Images from Vernier Acuity Masked by Noise

    Science.gov (United States)

    Ahumada, A. J.; Null, Cynthia H. (Technical Monitor)

    1996-01-01

    Letting external noise rather than internal noise limit discrimination performance allows information to be extracted about the observer's stimulus classification rule. A perceptual classification image is the correlation over trials between the noise amplitude at a spatial location and the observer's responses. If, for example, the observer followed the rule of the ideal observer, the perceptual classification image would be an estimate of the ideal observer filter, the difference between the two unmasked images being discriminated. Perceptual classification images were estimated for a vernier discrimination task. The display screen had 48 pixels per degree horizontally and vertically. The no-offset image had a dark horizontal line of 4 pixels, a 1 pixel space, and 4 more dark pixels. Classification images were based on 1600 discrimination trials with the line contrast adjusted to keep the error rate near 25 percent. In the offset image, the second line was one pixel higher. Unlike the ideal observer filter (a horizontal dipole), the observer perceptual classification images are strongly oriented. Fourier transforms of the classification images had a peak amplitude near one cycle per degree and an orientation near 25 degrees. The spatial spread is much more than image blur predicts, and probably indicates the spatial position uncertainty in the task.

  18. Prediction Error Associated with the Perceptual Segmentation of Naturalistic Events

    Science.gov (United States)

    Zacks, Jeffrey M.; Kurby, Christopher A.; Eisenberg, Michelle L.; Haroutunian, Nayiri

    2011-01-01

    Predicting the near future is important for survival and plays a central role in theories of perception, language processing, and learning. Prediction failures may be particularly important for initiating the updating of perceptual and memory systems and, thus, for the subjective experience of events. Here, we asked observers to make predictions…

  19. A comparison of multidimensional scaling methods for perceptual mapping

    NARCIS (Netherlands)

    Bijmolt, T.H.A.; Wedel, M.

    1999-01-01

    Multidimensional scaling has been applied to a wide range of marketing problems, in particular to perceptual mapping based on dissimilarity judgments. The introduction of methods based on the maximum likelihood principle is one of the most important developments. In this article, the authors compare

  20. 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…

  1. The stress hormone cortisol blocks perceptual learning in humans.

    Science.gov (United States)

    Dinse, Hubert R; Kattenstroth, J C; Lenz, M; Tegenthoff, M; Wolf, O T

    2017-03-01

    Cortisol, the primary glucocorticoid (GC) in humans, influences neuronal excitability and plasticity by acting on mineralocorticoid and glucocorticoid receptors. Cellular studies demonstrated that elevated GC levels affect neuronal plasticity, for example through a reduction of hippocampal long-term potentiation (LTP). At the behavioural level, after treatment with GCs, numerous studies have reported impaired hippocampal function, such as impaired memory retrieval. In contrast, relatively little is known about the impact of GCs on cortical plasticity and perceptual learning in adult humans. Therefore, in this study, we explored the impact of elevated GC levels on human perceptual learning. To this aim, we used a training-independent learning approach, where lasting changes in human perception can be induced by applying passive repetitive sensory stimulation (rss), the timing of which was determined from cellular LTP studies. In our placebo-controlled double-blind study, we used tactile LTP-like stimulation to induce improvements in tactile acuity (spatial two-point discrimination). Our results show that a single administration of hydrocortisone (30mg) completely blocked rss-induced changes in two-point discrimination. In contrast, the placebo group showed the expected rss-induced increase in two-point discrimination of over 14%. Our data demonstrate that high GC levels inhibit rss-induced perceptual learning. We suggest that the suppression of LTP, as previously reported in cellular studies, may explain the perceptual learning impairments observed here.

  2. The Perceptual Distortion of Height in Intercollegiate Debate.

    Science.gov (United States)

    Hensley, Wayne E.; Angoli, Marilyn

    Both balance and reinforcement theories were used in an examination of the perceptual distortion of height among 146 college debaters. Balance theory predicted that losers would distort winners' heights upward; reinforcement theory predicted that winners would distort losers' heights upward. The results confirmed both predictions. The possibility…

  3. Perceptual and Cognitive Development of Preschoolers in Soviet Psychology.

    Science.gov (United States)

    Pick, Herbert L., Jr.

    1980-01-01

    Experiments on the cognitive and perceptual development of three- to seven-year-old Soviet children are described, especially the work of L. A. Venger, N. N. Poddyakov, and D. B. El'Konin. Visual-action and visual-image thinking are illustrated. (GDC)

  4. 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…

  5. Perceptual hysteresis in the judgment of auditory pitch shift.

    Science.gov (United States)

    Chambers, Claire; Pressnitzer, Daniel

    2014-07-01

    Perceptual hysteresis can be defined as the enduring influence of the recent past on current perception. Here, hysteresis was investigated in a basic auditory task: pitch comparisons between successive tones. On each trial, listeners were presented with pairs of tones and asked to report the direction of subjective pitch shift, as either "up" or "down." All tones were complexes known as Shepard tones (Shepard, 1964), which comprise several frequency components at octave multiples of a base frequency. The results showed that perceptual judgments were determined both by stimulus-related factors (the interval ratio between the base frequencies within a pair) and by recent context (the intervals in the two previous trials). When tones were presented in ordered sequences, for which the frequency interval between tones was varied in a progressive manner, strong hysteresis was found. In particular, ambiguous stimuli that led to equal probabilities of "up" and "down" responses within a randomized context were almost fully determined within an ordered context. Moreover, hysteresis did not act on the direction of the reported pitch shift, but rather on the perceptual representation of each tone. Thus, hysteresis could be observed within sequences in which listeners varied between "up" and "down" responses, enabling us to largely rule out confounds related to response bias. The strength of the perceptual hysteresis observed suggests that the ongoing context may have a substantial influence on fundamental aspects of auditory perception, such as how we perceive the changes in pitch between successive sounds.

  6. Perceptual learning of acoustic noise generates memory-evoked potentials.

    Science.gov (United States)

    Andrillon, Thomas; Kouider, Sid; Agus, Trevor; Pressnitzer, Daniel

    2015-11-01

    Experience continuously imprints on the brain at all stages of life. The traces it leaves behind can produce perceptual learning [1], which drives adaptive behavior to previously encountered stimuli. Recently, it has been shown that even random noise, a type of sound devoid of acoustic structure, can trigger fast and robust perceptual learning after repeated exposure [2]. Here, by combining psychophysics, electroencephalography (EEG), and modeling, we show that the perceptual learning of noise is associated with evoked potentials, without any salient physical discontinuity or obvious acoustic landmark in the sound. Rather, the potentials appeared whenever a memory trace was observed behaviorally. Such memory-evoked potentials were characterized by early latencies and auditory topographies, consistent with a sensory origin. Furthermore, they were generated even on conditions of diverted attention. The EEG waveforms could be modeled as standard evoked responses to auditory events (N1-P2) [3], triggered by idiosyncratic perceptual features acquired through learning. Thus, we argue that the learning of noise is accompanied by the rapid formation of sharp neural selectivity to arbitrary and complex acoustic patterns, within sensory regions. Such a mechanism bridges the gap between the short-term and longer-term plasticity observed in the learning of noise [2, 4-6]. It could also be key to the processing of natural sounds within auditory cortices [7], suggesting that the neural code for sound source identification will be shaped by experience as well as by acoustics.

  7. A Multimedia Application: Spatial Perceptual Entropy of Multichannel Audio Signals

    Directory of Open Access Journals (Sweden)

    Chen Shuixian

    2010-01-01

    Full Text Available Usually multimedia data have to be compressed before transmitting, and higher compression rate, or equivalently lower bitrate, relieves the load of communication channels but impacts negatively the quality. We investigate the bitrate lower bound for perceptually lossless compression of a major type of multimedia—multichannel audio signals. This bound equals to the perceptible information rate of the signals. Traditionally, Perceptual Entropy (PE, based primarily on monaural hearing measures the perceptual information rate of individual channels. But PE cannot measure the spatial information captured by binaural hearing, thus is not suitable for estimating Spatial Audio Coding (SAC bitrate bound. To measure this spatial information, we build a Binaural Cue Physiological Perception Model (BCPPM on the ground of binaural hearing, which represents spatial information in the physical and physiological layers. This model enables computing Spatial Perceptual Entropy (SPE, the lower bitrate bound for SAC. For real-world stereo audio signals of various types, our experiments indicate that SPE reliably estimates their spatial information rate. Therefore, "SPE plus PE" gives lower bitrate bounds for communicating multichannel audio signals with transparent quality.

  8. A Multimedia Application: Spatial Perceptual Entropy of Multichannel Audio Signals

    Directory of Open Access Journals (Sweden)

    Shuixian Chen

    2010-01-01

    Full Text Available Usually multimedia data have to be compressed before transmitting, and higher compression rate, or equivalently lower bitrate, relieves the load of communication channels but impacts negatively the quality. We investigate the bitrate lower bound for perceptually lossless compression of a major type of multimedia—multichannel audio signals. This bound equals to the perceptible information rate of the signals. Traditionally, Perceptual Entropy (PE, based primarily on monaural hearing measures the perceptual information rate of individual channels. But PE cannot measure the spatial information captured by binaural hearing, thus is not suitable for estimating Spatial Audio Coding (SAC bitrate bound. To measure this spatial information, we build a Binaural Cue Physiological Perception Model (BCPPM on the ground of binaural hearing, which represents spatial information in the physical and physiological layers. This model enables computing Spatial Perceptual Entropy (SPE, the lower bitrate bound for SAC. For real-world stereo audio signals of various types, our experiments indicate that SPE reliably estimates their spatial information rate. Therefore, “SPE plus PE” gives lower bitrate bounds for communicating multichannel audio signals with transparent quality.

  9. 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…

  10. Mutual information, perceptual independence, and holistic face perception.

    Science.gov (United States)

    Fitousi, Daniel

    2013-07-01

    The concept of perceptual independence is ubiquitous in psychology. It addresses the question of whether two (or more) dimensions are perceived independently. Several authors have proposed perceptual independence (or its lack thereof) as a viable measure of holistic face perception (Loftus, Oberg, & Dillon, Psychological Review 111:835-863, 2004; Wenger & Ingvalson, Learning, Memory, and Cognition 28:872-892, 2002). According to this notion, the processing of facial features occurs in an interactive manner. Here, I examine this idea from the perspective of two theories of perceptual independence: the multivariate uncertainty analysis (MUA; Garner & Morton, Definitions, models, and experimental paradigms. Psychological Bulletin 72:233-259, 1969), and the general recognition theory (GRT; Ashby & Townsend, Psychological Review 93:154-179, 1986). The goals of the study were to (1) introduce the MUA, (2) examine various possible relations between MUA and GRT using numerical simulations, and (3) apply the MUA to two consensual markers of holistic face perception(-)recognition of facial features (Farah, Wilson, Drain, & Tanaka, Psychological Review 105:482-498, 1998) and the composite face effect (Young, Hellawell, & Hay, Perception 16:747-759, 1987). The results suggest that facial holism is generated by violations of several types of perceptual independence. They highlight the important theoretical role played by converging operations in the study of holistic face perception.

  11. Lexically-guided perceptual learning in speech processing

    NARCIS (Netherlands)

    Eisner, F.

    2006-01-01

    During listening to spoken language, the perceptual system needs to adapt frequently to changes in talkers, and thus to considerable interindividual variability in the articulation of a given speech sound. This thesis investigated a learning process which allows listeners to use stored lexical repre

  12. 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…

  13. 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…

  14. 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…

  15. The Relationship of Measured Perceptual Processes to School Learning.

    Science.gov (United States)

    Kephart, N. C.

    Ten test films were developed to measure aspects of children's visual perception which are difficult to assess through conventional paper and pencil tests. The film medium was selected because it allows the presentation of temporal, as well as spacial, aspects of the stimuli. Four areas of perceptual performance covered in the films are: (1)…

  16. Motoric Aids to Perceptual Training. The Slow Learner Series.

    Science.gov (United States)

    Chaney, Clara M.; Kephart, Newell C.

    Written from a developmental viewpoint, this book for parents and teachers presents both a theoretical orientation and perceptual motor activities for training children with learning disabilities, both the brain injured and the retarded. The theoretical basis for training generalized motor responses is considered in terms of motor perceptual…

  17. Innovative Perceptual Motor Activities: Programing Techniques That Work.

    Science.gov (United States)

    Sorrell, Howard M.

    1978-01-01

    A circuit approach and station techniques are used to depict perceptual motor games for handicapped and nonhandicapped children. Twenty activities are described in terms of objectives, materials, and procedures, and their focus on visual tracking, visual discrimination and copying of forms, spatial body perception, fine motor coordination, tactile…

  18. Attentional Modulation in Visual Cortex Is Modified during Perceptual Learning

    Science.gov (United States)

    Bartolucci, Marco; Smith, Andrew T.

    2011-01-01

    Practicing a visual task commonly results in improved performance. Often the improvement does not transfer well to a new retinal location, suggesting that it is mediated by changes occurring in early visual cortex, and indeed neuroimaging and neurophysiological studies both demonstrate that perceptual learning is associated with altered activity…

  19. 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.

  20. Perceptual, Categorical, and Affective Processing of Ambiguous Smiling Facial Expressions

    Science.gov (United States)

    Calvo, Manuel G.; Fernandez-Martin, Andres; Nummenmaa, Lauri

    2012-01-01

    Why is a face with a smile but non-happy eyes likely to be interpreted as happy? We used blended expressions in which a smiling mouth was incongruent with the eyes (e.g., angry eyes), as well as genuine expressions with congruent eyes and mouth (e.g., both happy or angry). Tasks involved detection of a smiling mouth (perceptual), categorization of…

  1. Perceptual anomalies in schizophrenia: integrating phenomenology and cognitive neuroscience.

    Science.gov (United States)

    Uhlhaas, Peter J; Mishara, Aaron L

    2007-01-01

    From phenomenological and experimental perspectives, research in schizophrenia has emphasized deficits in "higher" cognitive functions, including attention, executive function, as well as memory. In contrast, general consensus has viewed dysfunctions in basic perceptual processes to be relatively unimportant in the explanation of more complex aspects of the disorder, including changes in self-experience and the development of symptoms such as delusions. We present evidence from phenomenology and cognitive neuroscience that changes in the perceptual field in schizophrenia may represent a core impairment. After introducing the phenomenological approach to perception (Husserl, the Gestalt School), we discuss the views of Paul Matussek, Klaus Conrad, Ludwig Binswanger, and Wolfgang Blankenburg on perception in schizophrenia. These 4 psychiatrists describe changes in perception and automatic processes that are related to the altered experience of self. The altered self-experience, in turn, may be responsible for the emergence of delusions. The phenomenological data are compatible with current research that conceptualizes dysfunctions in perceptual processing as a deficit in the ability to combine stimulus elements into coherent object representations. Relationships of deficits in perceptual organization to cognitive and social dysfunction as well as the possible neurobiological mechanisms are discussed.

  2. Steady-state and dynamic network modes for perceptual expectation.

    Science.gov (United States)

    Choi, Uk-Su; Sung, Yul-Wan; Ogawa, Seiji

    2017-01-12

    Perceptual expectation can attenuate repetition suppression, the stimulus-induced neuronal response generated by repeated stimulation, suggesting that repetition suppression is a top-down modulatory phenomenon. However, it is still unclear which high-level brain areas are involved and how they interact with low-level brain areas. Further, the temporal range over which perceptual expectation can effectively attenuate repetition suppression effects remains unclear. To elucidate the details of this top-down modulatory process, we used two short and long inter-stimulus intervals for a perceptual expectation paradigm of paired stimulation. We found that top-down modulation enhanced the response to the unexpected stimulus when repetition suppression was weak and that the effect disappeared at 1,000 ms prior to stimulus exposure. The high-level areas involved in this process included the left inferior frontal gyrus (IFG_L) and left parietal lobule (IPL_L). We also found two systems providing modulatory input to the right fusiform face area (FFA_R): one from IFG_L and the other from IPL_L. Most importantly, we identified two states of networks through which perceptual expectation modulates sensory responses: one is a dynamic state and the other is a steady state. Our results provide the first functional magnetic resonance imaging (fMRI) evidence of temporally nested networks in brain processing.

  3. 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…

  4. Modelling perceptual characteristics of loudspeaker reproduction in a stereo setup

    DEFF Research Database (Denmark)

    Volk, Christer Peter; Bech, Søren; Pedersen, Torben Holm

    2017-01-01

    of the perceptual evaluation, four of the descriptors were found suited for modelling, with the purpose of developing metrics for prediction of Bass depth, Punch, Brilliance, and Dark-Bright. Bass depth and Punch were modelled as one due to high correlation between them. The experimental setup included loudspeaker...

  5. Representing and Inferring Visual Perceptual Skills in Dermatological Image Understanding

    Science.gov (United States)

    Li, Rui

    2013-01-01

    Experts have a remarkable capability of locating, perceptually organizing, identifying, and categorizing objects in images specific to their domains of expertise. Eliciting and representing their visual strategies and some aspects of domain knowledge will benefit a wide range of studies and applications. For example, image understanding may be…

  6. 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…

  7. Predicting the Perceptual Consequences of Hidden Hearing Loss

    Directory of Open Access Journals (Sweden)

    Andrew J. Oxenham

    2016-12-01

    Full Text Available Recent physiological studies in several rodent species have revealed that permanent damage can occur to the auditory system after exposure to a noise that produces only a temporary shift in absolute thresholds. The damage has been found to occur in the synapses between the cochlea’s inner hair cells and the auditory nerve, effectively severing part of the connection between the ear and the brain. This synaptopathy has been termed hidden hearing loss because its effects are not thought to be revealed in standard clinical, behavioral, or physiological measures of absolute threshold. It is currently unknown whether humans suffer from similar deficits after noise exposure. Even if synaptopathy occurs in humans, it remains unclear what the perceptual consequences might be or how they should best be measured. Here, we apply a simple theoretical model, taken from signal detection theory, to provide some predictions for what perceptual effects could be expected for a given loss of synapses. Predictions are made for a number of basic perceptual tasks, including tone detection in quiet and in noise, frequency discrimination, level discrimination, and binaural lateralization. The model’s predictions are in line with the empirical observations that a 50% loss of synapses leads to changes in threshold that are too small to be reliably measured. Overall, the model provides a simple initial quantitative framework for understanding and predicting the perceptual effects of synaptopathy in humans.

  8. 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.

  9. Perceptual tests of rhythmic similarity: II. Syllable rhythm

    NARCIS (Netherlands)

    Kim, J.; Davis, C.; Cutler, A.

    2008-01-01

    To segment continuous speech into its component words, listeners make use of language rhythm; because rhythm differs across languages, so do the segmentation procedures which listeners use. For each of stress-, syllable-and mora-based rhythmic structure, perceptual experiments have led to the discov

  10. The Multisensory Temporal Binding Window: Perceptual Fusion, Training, and Autism

    Directory of Open Access Journals (Sweden)

    Ryan A Stevenson

    2011-10-01

    Full Text Available The process of integrating information across sensory modalities is highly dependent upon the temporal coincidence of the inputs. Audiovisual information is integrated within a range of temporal offsets, known as the temporal binding window (TBW, which varies between individuals. Three particular findings relating to TBW have led us to a novel approach to address sensory integration impairments in children with autism. The first is that autistic children have an atypically wide TBW, as measured through manipulations of audiovisual illusions. Second, an individual's TBW is related to their ability to perceptually fuse audiovisual inputs, particularly as seen in the McGurk effect; the narrower the right TBW, the stronger the McGurk effect. The third finding is that the TBW is plastic. Through perceptual feedback training, our lab showed that individuals' right TBW can be narrowed. These three findings, which we will present, lead to a study of perceptual feedback training in autistic children, who may have the ability to narrow their TBW, with a possible positive impact on their ability to integrate multisensory information, specifically speech. We will conclude with the presentation of behavioral and electrophysiological data illustrating an atypical relationship between the TBW and perceptual fusion in ASD.

  11. Perceptual Load Influences Auditory Space Perception in the Ventriloquist Aftereffect

    Science.gov (United States)

    Eramudugolla, Ranmalee; Kamke, Marc. R.; Soto-Faraco, Salvador; Mattingley, Jason B.

    2011-01-01

    A period of exposure to trains of simultaneous but spatially offset auditory and visual stimuli can induce a temporary shift in the perception of sound location. This phenomenon, known as the "ventriloquist aftereffect", reflects a realignment of auditory and visual spatial representations such that they approach perceptual alignment despite their…

  12. 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.

  13. 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.

  14. Headache attributed to psychiatric disorders.

    Science.gov (United States)

    Guidetti, Vincenzo; Galli, Federica; Sheftell, Fred

    2010-01-01

    The association between psychiatric illness and headache is widely recognized. "Headache attributed to psychiatric disorder" is a new category of secondary headache introduced in the 2004 revision of the International Classification of Headache Disorders (ICHD-II) (Headache Classification Subcommittee of the International Headache Society, 2004). It represents a new, but not conclusive, step toward a better systematization of the topic "headache and psychological factors." From the early 1990s the involvement of psychological factors in headache disorders has been clearly identified as "psychiatric comorbidity." The current conceptualization of the term implies an association, more than casual, but likely not causal, between an index disease or disorder and one or more coexisting physical or psychological pathologies. Additionally, clarifying the direction, meaning, and weight of comorbidities has pathophysiological, nosological, course, and treatment implications. However, the study of comorbidity may present a series of difficulties related to the current understanding of the etiology and pathophysiology of diseases at the center of our attention. Sometimes, as happens in the subject of headache, we proceed against a background where many issues need to be clarified. In this chapter, we analyze the past and current literature, tracing the line from "migraine personality" to "psychiatric comorbidity" to "headache attributed to psychiatric disorders." Questions related to etiology, pathophysiology, and treatment options are discussed for different headache subtypes.

  15. Interrelationships among Age, Sex, and Depth of Sport Experience on a Complex Motor Task by 4- to 9-Year Old Children.

    Science.gov (United States)

    Kuhlman, Jolynn S.; Beitel, Patricia A.

    Age, gender, and/or previous experience seem to be related to the performance/learning of new perceptual motor tasks. This study sought to determine the relative interrelationships of age, gender, and the depth of sport experience on initial practice of a complex perceptual motor soccer task for 46 children 4- to 9-years-old who were enrolled in a…

  16. The role of textured material in supporting perceptual-motor functions.

    Directory of Open Access Journals (Sweden)

    Dominic Orth

    Full Text Available Simple deformation of the skin surface with textured materials can improve human perceptual-motor performance. The implications of these findings are inexpensive, adaptable and easily integrated clothing, equipment and tools for improving perceptual-motor functionality. However, some clarification is needed because mixed results have been reported in the literature, highlighting positive, absent and/or negative effects of added texture on measures of perceptual-motor performance. Therefore the aim of this study was to evaluate the efficacy of textured materials for enhancing perceptual-motor functionality. The systematic review uncovered two variables suitable for sub-group analysis within and between studies: participant age (groupings were 18-51 years and 64.7-79.4 years and experimental task (upright balance and walking. Evaluation of studies that observed texture effects during upright balance tasks, uncovered two additional candidate sub-groups for future work: vision (eyes open and eyes closed and stability (stable and unstable. Meta-analysis (random effects revealed that young participants improve performance by a small to moderate amount in upright balance tasks with added texture (SMD = 0.28, 95%CI = 0.46-0.09, Z = 2.99, P = 0.001; Tau(2 = 0.02; Chi(2 = 9.87, df = 6, P = 0.13; I(2 = 39.22. Significant heterogeneity was found in, the overall effect of texture: Tau(2 = 0.13; Chi(2 = 130.71, df = 26, P<0.0001; I(2 = 85.98%, pooled samples in upright balance tasks: Tau(2 = 0.09; Chi(2 = 101.57, df = 13, P<0.001; I(2 = 72.67%, and in elderly in upright balance tasks: Tau(2 = 0.16; Chi(2 = 39.42, df = 5, P<0.001; I(2 = 83.05%. No effect was shown for walking tasks: Tau(2 = 0.00; Chi(2 = 3.45, df = 4, P = 0.27, I(2 = 22.99%. Data provides unequivocal support for utilizing textured materials in young healthy populations for improving

  17. 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.

  18. Theory of Mind, Causal Attribution and Paranoia in Asperger Syndrome.

    Science.gov (United States)

    Blackshaw, Alison J.; Kinderman, Peter; Hare, Dougal J.; Hatton, Chris

    2001-01-01

    Twenty-five participants (ages 15-40) with Asperger syndrome scored significantly higher on a measure of paranoia and lower on a measure of theory of mind, compared with a control group. They did not differ in self-concept and causal attributions. A regression analysis highlighted private self-consciousness as the only predictor of paranoia.…

  19. 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…

  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. Effects of aging on peripheral and central auditory processing in rats.

    Science.gov (United States)

    Costa, Margarida; Lepore, Franco; Prévost, François; Guillemot, Jean-Paul

    2016-08-01

    Hearing loss is a hallmark sign in the elderly population. Decline in auditory perception provokes deficits in the ability to localize sound sources and reduces speech perception, particularly in noise. In addition to a loss of peripheral hearing sensitivity, changes in more complex central structures have also been demonstrated. Related to these, this study examines the auditory directional maps in the deep layers of the superior colliculus of the rat. Hence, anesthetized Sprague-Dawley adult (10 months) and aged (22 months) rats underwent distortion product of otoacoustic emissions (DPOAEs) to assess cochlear function. Then, auditory brainstem responses (ABRs) were assessed, followed by extracellular single-unit recordings to determine age-related effects on central auditory functions. DPOAE amplitude levels were decreased in aged rats although they were still present between 3.0 and 24.0 kHz. ABR level thresholds in aged rats were significantly elevated at an early (cochlear nucleus - wave II) stage in the auditory brainstem. In the superior colliculus, thresholds were increased and the tuning widths of the directional receptive fields were significantly wider. Moreover, no systematic directional spatial arrangement was present among the neurons of the aged rats, implying that the topographical organization of the auditory directional map was abolished. These results suggest that the deterioration of the auditory directional spatial map can, to some extent, be attributable to age-related dysfunction at more central, perceptual stages of auditory processing.

  2. Speechreading in Deaf Adults with Cochlear Implants: Evidence for Perceptual Compensation

    Science.gov (United States)

    Pimperton, Hannah; Ralph-Lewis, Amelia; MacSweeney, Mairéad

    2017-01-01

    Previous research has provided evidence for a speechreading advantage in congenitally deaf adults compared to hearing adults. A ‘perceptual compensation’ account of this finding proposes that prolonged early onset deafness leads to a greater reliance on visual, as opposed to auditory, information when perceiving speech which in turn results in superior visual speech perception skills in deaf adults. In the current study we tested whether previous demonstrations of a speechreading advantage for profoundly congenitally deaf adults with hearing aids, or no amplificiation, were also apparent in adults with the same deafness profile but who have experienced greater access to the auditory elements of speech via a cochlear implant (CI). We also tested the prediction that, in line with the perceptual compensation account, receiving a CI at a later age is associated with superior speechreading skills due to later implanted individuals having experienced greater dependence on visual speech information. We designed a speechreading task in which participants viewed silent videos of 123 single words spoken by a model and were required to indicate which word they thought had been said via a free text response. We compared congenitally deaf adults who had received CIs in childhood or adolescence (N = 15) with a comparison group of hearing adults (N = 15) matched on age and education level. The adults with CI showed significantly better scores on the speechreading task than the hearing comparison group. Furthermore, within the group of adults with CI, there was a significant positive correlation between age at implantation and speechreading performance; earlier implantation was associated with lower speechreading scores. These results are both consistent with the hypothesis of perceptual compensation in the domain of speech perception, indicating that more prolonged dependence on visual speech information in speech perception may lead to improvements in the perception of

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

    Directory of Open Access Journals (Sweden)

    Wei eWang

    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.

  4. 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.

  5. 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.

  6. Electrophysiological evidence for early perceptual facilitation and efficient categorization of self-related stimuli during an Implicit Association Test measuring neuroticism.

    Science.gov (United States)

    Fleischhauer, Monika; Strobel, Alexander; Diers, Kersten; Enge, Sören

    2014-02-01

    The Implicit Association Test (IAT) is a widely used latency-based categorization task that indirectly measures the strength of automatic associations between target and attribute concepts. So far, little is known about the perceptual and cognitive processes underlying personality IATs. Thus, the present study examined event-related potential indices during the execution of an IAT measuring neuroticism (N  =  70). The IAT effect was strongly modulated by the P1 component indicating early facilitation of relevant visual input and by a P3b-like late positive component reflecting the efficacy of stimulus categorization. Both components covaried, and larger amplitudes led to faster responses. The results suggest a relationship between early perceptual and semantic processes operating at a more automatic, implicit level and later decision-related categorization of self-relevant stimuli contributing to the IAT effect.

  7. Perceptual learning in patients with macular degeneration

    Directory of Open Access Journals (Sweden)

    Tina ePlank

    2014-10-01

    Full Text Available Patients with age-related macular degeneration (AMD or hereditary macular dystrophies (JMD rely on an efficient use of their peripheral visual field. We trained eight AMD and five JMD patients to perform a texture-discrimination task (TDT at their preferred retinal locus (PRL used for fixation. Six training sessions of approximately one hour duration were conducted over a period of approximately 3 weeks. Before, during and after training twelve patients and twelve age-matched controls (the data from two controls had to be discarded later took part in three functional magnetic resonance imaging (fMRI sessions to assess training-related changes in the BOLD response in early visual cortex. Patients benefited from the training measurements as indexed by significant decrease (p=.001 in the stimulus onset asynchrony (SOA between the presentation of the texture target on background and the visual mask, and in a significant location specific effect of the PRL with respect to hit rate (p=.014. The following trends were observed: (i Improvement in Vernier acuity for an eccentric line-bisection task; (ii positive correlation between the development of BOLD signals in early visual cortex and initial fixation stability (r=0.531; (iii positive correlation between the increase in task performance and initial fixation stability (r=0.730. The first two trends were non-significant, whereas the third trend was significant at p=.014, Bonferroni corrected. Consequently, our exploratory study suggests that training on the TDT can enhance eccentric vision in patients with central vision loss. This enhancement is accompanied by a modest alteration in the BOLD response in early visual cortex.

  8. Perceptual-Cognitive Expertise in Elite Volleyball Players

    Science.gov (United States)

    Alves, Heloisa; Voss, Michelle W.; Boot, Walter R.; Deslandes, Andrea; Cossich, Victor; Salles, Jose Inacio; Kramer, Arthur F.

    2013-01-01

    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. PMID:23471100

  9. Perceptual assimilation and discrimination of non-native vowel contrasts.

    Science.gov (United States)

    Tyler, Michael D; Best, Catherine T; Faber, Alice; Levitt, Andrea G

    2014-01-01

    Research on language-specific tuning in speech perception has focused mainly on consonants, while that on non-native vowel perception has failed to address whether the same principles apply. Therefore, non-native vowel perception was investigated here in light of relevant theoretical models: the Perceptual Assimilation Model (PAM) and the Natural Referent Vowel (NRV) framework. American-English speakers completed discrimination and native language assimilation (categorization and goodness rating) tests on six nonnative vowel contrasts. Discrimination was consistent with PAM assimilation types, but asymmetries predicted by NRV were only observed for single-category assimilations, suggesting that perceptual assimilation might modulate the effects of vowel peripherality on non-native vowel perception.

  10. Perceptual assimilation and discrimination of non-native vowel contrasts

    Science.gov (United States)

    Tyler, Michael D.; Best, Catherine T.; Faber, Alice; Levitt, Andrea G.

    2014-01-01

    Research on language-specific tuning in speech perception has focused mainly on consonants, while that on non-native vowel perception has failed to address whether the same principles apply. Therefore, non-native vowel perception was investigated here in light of relevant theoretical models: The Perceptual Assimilation Model (PAM) and the Natural Referent Vowel (NRV) framework. American-English speakers completed discrimination and L1-assimilation (categorization and goodness rating) tests on six non-native vowel contrasts. Discrimination was consistent with PAM assimilation types, but asymmetries predicted by NRV were only observed for single-category assimilations, suggesting that perceptual assimilation might modulate the effects of vowel peripherality on non-native vowel perception. PMID:24923313

  11. A Weber-like law for perceptual learning.

    Science.gov (United States)

    Astle, Andrew T; Li, Roger W; Webb, Ben S; Levi, Dennis M; McGraw, Paul V

    2013-01-01

    What determines how much an organism can learn? One possibility is that the neural factors that limit sensory performance prior to learning, place an upper limit on the amount of learning that can take place. We tested this idea by comparing learning on a sensory task where performance is limited by cortical mechanisms, at two retinal eccentricities. Prior to learning, visual performance at the two eccentricities was either unmatched or equated in two different ways (through spatial scaling or visual crowding). The magnitude of learning was equivalent when initial levels of performance were matched regardless of how performance was equated. The magnitude of learning was a constant proportion of initial performance. This Weber-like law for perceptual learning demonstrates that it should be possible to predict the degree of perceptual improvement and the final level of performance that can be achieved via sensory training, regardless of what cortical constraint limits performance.

  12. Perceptual fluency and judgments of vocal aesthetics and stereotypicality.

    Science.gov (United States)

    Babel, Molly; McGuire, Grant

    2015-05-01

    Research has shown that processing dynamics on the perceiver's end determine aesthetic pleasure. Specifically, typical objects, which are processed more fluently, are perceived as more attractive. We extend this notion of perceptual fluency to judgments of vocal aesthetics. Vocal attractiveness has traditionally been examined with respect to sexual dimorphism and the apparent size of a talker, as reconstructed from the acoustic signal, despite evidence that gender-specific speech patterns are learned social behaviors. In this study, we report on a series of three experiments using 60 voices (30 females) to compare the relationship between judgments of vocal attractiveness, stereotypicality, and gender categorization fluency. Our results indicate that attractiveness and stereotypicality are highly correlated for female and male voices. Stereotypicality and categorization fluency were also correlated for male voices, but not female voices. Crucially, stereotypicality and categorization fluency interacted to predict attractiveness, suggesting the role of perceptual fluency is present, but nuanced, in judgments of human voices.

  13. 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

  14. Perceptual image hashing via feature points: performance evaluation and tradeoffs.

    Science.gov (United States)

    Monga, Vishal; Evans, Brian L

    2006-11-01

    We propose an image hashing paradigm using visually significant feature points. The feature points should be largely invariant under perceptually insignificant distortions. To satisfy this, we propose an iterative feature detector to extract significant geometry preserving feature points. We apply probabilistic quantization on the derived features to introduce randomness, which, in turn, reduces vulnerability to adversarial attacks. The proposed hash algorithm withstands standard benchmark (e.g., Stirmark) attacks, including compression, geometric distortions of scaling and small-angle rotation, and common signal-processing operations. Content changing (malicious) manipulations of image data are also accurately detected. Detailed statistical analysis in the form of receiver operating characteristic (ROC) curves is presented and reveals the success of the proposed scheme in achieving perceptual robustness while avoiding misclassification.

  15. Albert's test: a neglected test of perceptual neglect.

    Science.gov (United States)

    Fullerton, K J; McSherry, D; Stout, R W

    1986-02-22

    Disorders of perception are thought to be important in predicting the outcome from stroke, but their exact significance is difficult to define because of lack of standardised terminology and diagnostic methods. In a prospective study of 205 unselected stroke patients, perceptual neglect, assessed by a standardised test battery, was found in 49% of patients with lesions of the non-dominant hemisphere and in 25% with lesions of the dominant hemisphere. One component of the test battery was a simple test described by Albert in which patients cross out lines ruled in a standard fashion on a sheet of paper; this was easy to administer and related closely to neglect diagnosed by the test battery as a whole. Results of Albert's test were a significant predictor of both mortality and functional activity six months after the stroke, independent of the influence of other clinical, neurological, laboratory, and social factors. The full test battery for perceptual neglect was of no significant additional predictive value.

  16. 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

  17. Transfer of motor and perceptual skills from basketball to darts.

    Science.gov (United States)

    Rienhoff, Rebecca; Hopwood, Melissa J; Fischer, Lennart; Strauss, Bernd; Baker, Joseph; Schorer, Jörg

    2013-01-01

    The quiet eye is a perceptual skill associated with expertise and superior performance; however, little is known about the transfer of quiet eye across domains. We attempted to replicate previous skill-based differences in quiet eye and investigated whether transfer of motor and perceptual skills occurs between similar tasks. Throwing accuracy and quiet eye duration for skilled and less-skilled basketball players were examined in basketball free throw shooting and the transfer task of dart throwing. Skilled basketball players showed significantly higher throwing accuracy and longer quiet eye duration in the basketball free throw task compared to their less-skilled counterparts. Further, skilled basketball players showed positive transfer from basketball to dart throwing in accuracy but not in quiet eye duration. Our results raise interesting questions regarding the measurement of transfer between skills.

  18. Towards perception awareness: Perceptual event detection for Brain computer interfaces.

    Science.gov (United States)

    Nejati, Hossein; Tsourides, Kleovoulos; Pomponiu, Victor; Ehrenberg, Evan C; Ngai-Man Cheung; Sinha, Pawan

    2015-08-01

    Brain computer interface (BCI) technology is becoming increasingly popular in many domains such as entertainment, mental state analysis, and rehabilitation. For robust performance in these domains, detecting perceptual events would be a vital ability, enabling adaptation to and act on the basis of user's perception of the environment. Here we present a framework to automatically mine spatiotemporal characteristics of a given perceptual event. As this "signature" is derived directly from subject's neural behavior, it can serve as a representation of the subject's perception of the targeted scenario, which in turn allows a BCI system to gain a new level of context awareness: perception awareness. As a proof of concept, we show the application of the proposed framework on MEG signal recordings from a face perception study, and the resulting temporal and spatial characteristics of the derived neural signature, as well as it's compatibility with the neuroscientific literature on face perception.

  19. Attributions and Relapse in Opiate Addicts.

    Science.gov (United States)

    Bradley, Brendan P.; And Others

    1992-01-01

    Investigated whether attributions of opiate addicts would predict abstinence and reactions to abstinence violations. Found that addicts who at admission attributed to themselves greater responsibility for negative outcomes and who attributed relapse episodes to more personally controllable factors were subsequently more likely either to be…

  20. Visual-perceptual-kinesthetic inputs on influencing writing performances in children with handwriting difficulties.

    Science.gov (United States)

    Tse, Linda F L; Thanapalan, Kannan C; Chan, Chetwyn C H

    2014-02-01

    This study investigated the role of visual-perceptual input in writing Chinese characters among senior school-aged children who had handwriting difficulties (CHD). The participants were 27 CHD (9-11 years old) and 61 normally developed control. There were three writing conditions: copying, and dictations with or without visual feedback. The motor-free subtests of the Developmental Test of Visual Perception (DTVP-2) were conducted. The CHD group showed significantly slower mean speeds of character production and less legibility of produced characters than the control group in all writing conditions (psDTVP-2 was significantly correlated with the legibility among CHD (r=-0.62, p=0.001). Poor legibility seems to be related to the less-intact spatial representation of the characters in working memory, which can be rectified by viewing the characters during writing. Visual feedback regarding one's own actions in writing can also improve legibility of characters among these children.

  1. 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

    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。%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.

  2. 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.

  3. The effect of perceptual grouping on selective attention

    OpenAIRE

    Chow, Hiu-mei.; 周曉薇.

    2013-01-01

    Perceptual grouping plays an indispensable role on attention distribution. An example of this interaction is the impaired visual search performance when the target overlaps with a task-irrelevant salient distractor organized to a snake-like configuration by collinear bars, and when the collinear distractor is long enough (Jingling & Tseng, 2013). This phenomenon is puzzling because it is opposite to our understanding of attention capture which predicts search facilitation instead of impairme...

  4. Perceptual assimilation and discrimination of non-native vowel contrasts

    OpenAIRE

    2014-01-01

    Research on language-specific tuning in speech perception has focused mainly on consonants, while that on non-native vowel perception has failed to address whether the same principles apply. Therefore, non-native vowel perception was investigated here in light of relevant theoretical models: The Perceptual Assimilation Model (PAM) and the Natural Referent Vowel (NRV) framework. American-English speakers completed discrimination and L1-assimilation (categorization and goodnes...

  5. 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.

  6. Atypical Prosody in Asperger Syndrome: Perceptual and Acoustic Measurements

    OpenAIRE

    Marisa G. Filipe; Frota, Sónia; Castro, São Luís; Vicente, Selene G.

    2014-01-01

    It is known that individuals with Asperger syndrome (AS) may show no problems with regard to what is said (e.g., lexical content) but tend to have difficulties in how utterances are produced, i.e., they may show prosodic impairments. In the present study, we focus on the use of prosodic features to express grammatical meaning. Specifically, we explored the sentence type difference between statements and questions that is conveyed by intonation, using perceptual and acoustic measurements. Chil...

  7. How much gravity is needed to establish the perceptual upright?

    Science.gov (United States)

    Harris, Laurence R; Herpers, Rainer; Hofhammer, Thomas; Jenkin, Michael

    2014-01-01

    Might the gravity levels found on other planets and on the moon be sufficient to provide an adequate perception of upright for astronauts? Can the amount of gravity required be predicted from the physiological threshold for linear acceleration? The perception of upright is determined not only by gravity but also visual information when available and assumptions about the orientation of the body. Here, we used a human centrifuge to simulate gravity levels from zero to earth gravity along the long-axis of the body and measured observers' perception of upright using the Oriented Character Recognition Test (OCHART) with and without visual cues arranged to indicate a direction of gravity that differed from the body's long axis. This procedure allowed us to assess the relative contribution of the added gravity in determining the perceptual upright. Control experiments off the centrifuge allowed us to measure the relative contributions of normal gravity, vision, and body orientation for each participant. We found that the influence of 1 g in determining the perceptual upright did not depend on whether the acceleration was created by lying on the centrifuge or by normal gravity. The 50% threshold for centrifuge-simulated gravity's ability to influence the perceptual upright was at around 0.15 g, close to the level of moon gravity but much higher than the threshold for detecting linear acceleration along the long axis of the body. This observation may partially explain the instability of moonwalkers but is good news for future missions to Mars.

  8. Visual Motor and Perceptual Task Performance in Astigmatic Students

    Directory of Open Access Journals (Sweden)

    Erin M. Harvey

    2017-01-01

    Full Text Available Purpose. To determine if spectacle corrected and uncorrected astigmats show reduced performance on visual motor and perceptual tasks. Methods. Third through 8th grade students were assigned to the low refractive error control group (astigmatism < 1.00 D, myopia < 0.75 D, hyperopia < 2.50 D, and anisometropia < 1.50 D or bilateral astigmatism group (right and left eye ≥ 1.00 D based on cycloplegic refraction. Students completed the Beery-Buktenica Developmental Test of Visual Motor Integration (VMI and Visual Perception (VMIp. Astigmats were randomly assigned to testing with/without correction and control group was tested uncorrected. Analyses compared VMI and VMIp scores for corrected and uncorrected astigmats to the control group. Results. The sample included 333 students (control group 170, astigmats tested with correction 75, and astigmats tested uncorrected 88. Mean VMI score in corrected astigmats did not differ from the control group (p=0.829. Uncorrected astigmats had lower VMI scores than the control group (p=0.038 and corrected astigmats (p=0.007. Mean VMIp scores for uncorrected (p=0.209 and corrected astigmats (p=0.124 did not differ from the control group. Uncorrected astigmats had lower mean scores than the corrected astigmats (p=0.003. Conclusions. Uncorrected astigmatism influences visual motor and perceptual task performance. Previously spectacle treated astigmats do not show developmental deficits on visual motor or perceptual tasks when tested with correction.

  9. Enhancement and suppression in the visual field under perceptual load.

    Science.gov (United States)

    Parks, Nathan A; Beck, Diane M; Kramer, Arthur F

    2013-01-01

    The perceptual load theory of attention proposes that the degree to which visual distractors are processed is a function of the attentional demands of a task-greater demands increase filtering of irrelevant distractors. The spatial configuration of such filtering is unknown. Here, we used steady-state visual evoked potentials (SSVEPs) in conjunction with time-domain event-related potentials (ERPs) to investigate the distribution of load-induced distractor suppression and task-relevant enhancement in the visual field. Electroencephalogram (EEG) was recorded while subjects performed a foveal go/no-go task that varied in perceptual load. Load-dependent distractor suppression was assessed by presenting a contrast reversing ring at one of three eccentricities (2, 6, or 11°) during performance of the go/no-go task. Rings contrast reversed at 8.3 Hz, allowing load-dependent changes in distractor processing to be tracked in the frequency-domain. ERPs were calculated to the onset of stimuli in the load task to examine load-dependent modulation of task-relevant processing. Results showed that the amplitude of the distractor SSVEP (8.3 Hz) was attenuated under high perceptual load (relative to low load) at the most proximal (2°) eccentricity but not at more eccentric locations (6 or 11°). Task-relevant ERPs revealed a significant increase in N1 amplitude under high load. These results are consistent with a center-surround configuration of load-induced enhancement and suppression in the visual field.

  10. Perceptual asymmetry reveals neural substrates underlying stereoscopic transparency.

    Science.gov (United States)

    Tsirlin, Inna; Allison, Robert S; Wilcox, Laurie M

    2012-02-01

    We describe a perceptual asymmetry found in stereoscopic perception of overlaid random-dot surfaces. Specifically, the minimum separation in depth needed to perceptually segregate two overlaid surfaces depended on the distribution of dots across the surfaces. With the total dot density fixed, significantly larger inter-plane disparities were required for perceptual segregation of the surfaces when the front surface had fewer dots than the back surface compared to when the back surface was the one with fewer dots. We propose that our results reflect an asymmetry in the signal strength of the front and back surfaces due to the assignment of the spaces between the dots to the back surface by disparity interpolation. This hypothesis was supported by the results of two experiments designed to reduce the imbalance in the neuronal response to the two surfaces. We modeled the psychophysical data with a network of inter-neural connections: excitatory within-disparity and inhibitory across disparity, where the spread of disparity was modulated according to figure-ground assignment. These psychophysical and computational findings suggest that stereoscopic transparency depends on both inter-neural interactions of disparity-tuned cells and higher-level processes governing figure ground segregation.

  11. 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.

  12. Perceptual rivalry: reflexes reveal the gradual nature of visual awareness.

    Directory of Open Access Journals (Sweden)

    Marnix Naber

    Full Text Available 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 optokinetic nystagmus (OKN; second, we use a continuous input device (analog joystick to allow observers a gradual subjective report. We find that the "reflexes" reflect the percept rather than the physical stimulus. Both reflexes show a gradual dependence on the time relative to perceptual transitions. Similarly, observers' joystick deflections, which are highly correlated with the reflex measures, indicate gradual transitions. Physically simulating wave-like transitions between percepts suggest piece-meal rivalry (i.e., different regions of space belonging to distinct percepts as one possible explanation for the gradual transitions. Furthermore, the reflexes show that dominance durations depend on whether or not the percept is actively reported. In addition, reflexes respond to transitions with shorter latencies than the subjective report and show an abundance of short dominance durations. This failure to report fast changes in dominance may result from limited access of introspection to rivalry dynamics. In sum, reflexes reveal that rivalry is a gradual process, rivalry's dynamics is modulated by the required action (response mode, and that rapid transitions in perceptual dominance can slip away from awareness.

  13. Golden Perception: Simulating Perceptual Habits of the Past

    Directory of Open Access Journals (Sweden)

    Claus-Christian Carbon

    2013-09-01

    Full Text Available Medieval times were neither dark nor grey; natural light illuminated colourful scenes depicted in paintings through coloured windows and via artificial beeswax candlelight. When we enter, for example, a church to inspect its historic treasures ranging from mosaics to depictions of saints, we do this under quite unfavourable conditions; particularly as we mainly depend on artificial halogen, LED or fluorescent light for illuminating the desired object. As these light spectrums are different from the natural light conditions under which the old masterpieces were previously developed and perceived, the perceptual effects may dramatically differ, leading to significantly altered affective and cognitive processing. Different qualities of processing might particularly be triggered when perceiving artworks which deal with specific material prone to strong interaction with idiosyncratic light conditions, for instance gold-leafed surfaces that literally start to glow when lit by candles. We tested the perceptual experiences of a figurative piece of art which we created in 3 (foreground by 3 (background versions, illuminated under three different light conditions (daylight, coloured light and beeswax candlelight. Results demonstrated very different perceptual experiences with stunning effects for the interaction of the specific painting depicted on a gold-leafed background lit by candlelight.

  14. Perceptual Fidelity vs. Engineering Compromises In Virtual Acoustic Displays

    Science.gov (United States)

    Wenzel, Elizabeth M.; Ahumada, Albert (Technical Monitor)

    1997-01-01

    Immersive, three-dimensional displays are increasingly becoming a goal of advanced human-machine interfaces. While the technology for achieving truly useful multisensory environments is still being developed, techniques for generating three-dimensional sound are now both sophisticated and practical enough to be applied to acoustic displays. The ultimate goal of virtual acoustics is to simulate the complex acoustic field experienced by a listener freely moving around within an environment. Of course, such complexity, freedom of movement and interactively is not always possible in a "true" virtual environment, much less in lower-fidelity multimedia systems. However, many of the perceptual and engineering constraints (and frustrations) that researchers, engineers and listeners have experienced in virtual audio are relevant to multimedia. In fact, some of the problems that have been studied will be even more of an issue for lower fidelity systems that are attempting to address the requirements of a huge, diverse and ultimately unknown audience. Examples include individual differences in head-related transfer functions, a lack of real interactively (head-tracking) in many multimedia displays, and perceptual degradation due to low sampling rates and/or low-bit compression. This paper discusses some of the engineering Constraints faced during implementation of virtual acoustic environments and the perceptual consequences of these constraints. Specific examples are given for NASA applications such as telerobotic control, aeronautical displays, and shuttle launch communications. An attempt will also be made to relate these issues to low-fidelity implementations such as the internet.

  15. Perceptual Fidelity Versus Engineering Compromises in Virtual Acoustic Displays

    Science.gov (United States)

    Wenzel, Elizabeth M.; Ellis, Stephen R. (Technical Monitor); Frey, Mary Anne (Technical Monitor); Schneider, Victor S. (Technical Monitor)

    1997-01-01

    Immersive, three-dimensional displays are increasingly becoming a goal of advanced human-machine interfaces. While the technology for achieving truly useful multisensory environments is still being developed, techniques for generating three-dimensional sound are now both sophisticated and practical enough to be applied to acoustic displays. The ultimate goal of virtual acoustics is to simulate the complex acoustic field experienced by a listener freely moving around within an environment. Of course, such complexity, freedom of movement and interactivity is not always possible in a 'true' virtual environment, much less in lower-fidelity multimedia systems. However, many of the perceptual and engineering constraints (and frustrations) that researchers, engineers and listeners have experienced in virtual audio are relevant to multimedia. In fact, some of the problems that have been studied will be even more of an issue for lower fidelity systems that are attempting to address the requirements of a huge, diverse and ultimately unknown audience. Examples include individual differences in head-related transfer functions, A lack of real interactively (head-tracking) in many multimedia displays, and perceptual degradation due to low sampling rates and/or low-bit compression. This paper discusses some of the engineering constraints faced during implementation of virtual acoustic environments and the perceptual consequences of these constraints. Specific examples are given for NASA applications such as telerobotic control, aeronautical displays, and shuttle launch communications. An attempt will also be made to relate these issues to low-fidelity implementations such as the internet.

  16. The brain's specialized systems for aesthetic and perceptual judgment.

    Science.gov (United States)

    Ishizu, T; Zeki, S

    2013-05-01

    We recorded brain activity when 21 subjects judged the beauty (aesthetic or affective judgment) and brightness (perceptual or cognitive judgment) of simultaneously presented paintings. Aesthetic judgments engaged medial and lateral subdivisions of the orbitofrontal cortex as well as subcortical stations associated with affective motor planning (globus pallidus, putamen-claustrum, amygdala, and cerebellar vermis), whereas the motor, premotor and supplementary motor areas, as well as the anterior insula and the dorsolateral prefrontal cortex, were engaged by both kinds of judgment. The results lead us to conclude: (i) that there is a functional specialization for judgment, with aesthetic judgments engaging distinct systems, in addition to those that they share with perceptual judgments; (ii) that the systems engaged by affective judgments are those in which activity correlates with polar experiences (e.g. love-hate, beauty-ugliness, and attraction-repulsion); and (iii) that there is also a functional specialization in the motor pathways, with aesthetic judgments engaging motor systems not engaged by perceptual judgments, in addition to those engaged by both kinds of judgment.

  17. 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.

  18. 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.

  19. 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.

  20. A longitudinal investigation of maternal influences on the development of child hostile attributions and aggression.

    Science.gov (United States)

    Healy, Sarah J; Murray, Lynne; Cooper, Peter J; Hughes, Claire; Halligan, Sarah L

    2015-01-01

    Aggression in children is associated with an enhanced tendency to attribute hostile intentions to others. However, limited information is available regarding the factors that contribute to the development of such hostile attribution tendencies. We examined factors that contribute to individual differences in child hostile attributions and aggression, focusing on potential pathways from maternal hostile attributions via negative parenting behavior. We conducted a longitudinal study of 98 mothers and children (47 male, 51 female), recruited from groups experiencing high and low levels of psychosocial adversity. Maternal hostile attributions, observed parenting, and child behaviour were assessed at 18 months and 5 years child age, and child hostile attributions were also examined at 5 years. Independent assessments of maternal and child processes were utilized where possible. Analyses provided support for a direct influence of maternal hostile attributions on the development of child hostile attributions and aggressive behaviour. Maternal hostile attributions were also associated with negative parenting behaviour, which in turn influenced child adjustment. Even taking account of possible parenting influences and preexisting child difficulties, hostile attributions in the mother showed a direct link with child aggression at 5 years. Maternal hostile attributions were themselves related to psychosocial adversity. We conclude that maternal hostile attributions are prevalent in high-risk samples and are related to less optimal parenting behaviour, child hostile attributions, and child aggression. Targeting hostile maternal cognitions may be a useful adjunct to parenting programs.

  1. 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…

  2. 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…

  3. Conformity in the Asch Task as a Function of Age.

    Science.gov (United States)

    Walker, Michael B.; Andrade, Maria G.

    1996-01-01

    Replicates the Asch conformity experiment (two participants pretend to misjudge a shorter line for a longer one in an attempt to influence a third participant) and applies it to 110 school children ages 3 to 17. Indicates that conformity decreases with age in perceptually ambiguous tasks. (MJP)

  4. Labeled experimental choice design for estimating attribute and availability cross effects with N attributes and specific brand attribute levels

    DEFF Research Database (Denmark)

    Nguyen, Thong Tien

    2011-01-01

    , orthogonal design is not available for every situation. Instead, efficient design based on computerized design algorithm is always available. This paper presents the method of efficient design for estimating brand models having attribute and availability cross effects. The paper gives a framework...... for implementing designs that is efficient enough to estimate model with N brands, each brand have K attributes, and brand attribute has specific levels. The paper also illustrates an example in food consumption study....

  5. 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.

  6. Developmental Trends of Black Spruce Fibre Attributes in Maturing Plantations

    Directory of Open Access Journals (Sweden)

    Peter F. Newton

    2016-01-01

    Full Text Available This study assessed the temporal developmental patterns of commercially relevant fibre attributes (tracheid length and diameters, wall thickness, specific surface area, wood density, microfibril angle, fibre coarseness, and modulus of elasticity and their interrelationships within maturing black spruce (Picea mariana (Mill. B.S.P. plantations. A size-based stratified random sample procedure within 5 semimature plantations located in the Canadian Boreal Forest Region was used to select 50 trees from which radial cross-sectional xylem sequences at breast-height (1.3 m were cut and analyzed. Statistically, the graphical and linear correlation analyses indicated that the attributes exhibited significant (p≤0.05 relationships among themselves and with morphological tree characteristics. Relative variation of each annually measured attribute declined with increasing size class (basal area quintile. The transitional shifts in temporal correlation patterns occurring at the time of approximate crown closure where suggestive of intrinsic differences in juvenile and mature wood formation processes. The temporal cumulative development patterns of all 8 of the annually measured attributes varied systematically with tree size and exhibited the most rapid rates of change before the trees reached a cambial age of 20 years. At approximately 50 years after establishment, plantation mean attribute values were not dissimilar from those reported for more mature natural-origin stands.

  7. Attributions and Attitudes of Mothers and Fathers in Jordan.

    Science.gov (United States)

    Al-Hassan, Suha; Takash, Hanan

    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 in Jordan. DESIGN: Interviews were conducted with both mothers and fathers in 112 families. RESULTS: There were no significant main effects of gender on any of the constructs of interest. Mothers and fathers reported similar levels of attributions regarding uncontrollable success, adult-controlled failure, and child-controlled failure in the same family. Regarding attitudes, mothers and fathers reported greater progressive attitudes than authoritarian attitudes. Large, significant correlations were found for concordance between parents in the same family on all seven attributions and attitudes examined; all remained significant after controlling for parents' age, education, and possible social desirability bias. Significant positive correlations were found for mothers' and fathers' attributions regarding uncontrollable success, adult-controlled failure, child-controlled failure, perceived control over failure, progressive attitudes, authoritarian attitudes, and modernity of attitudes. CONCLUSIONS: This study concluded that in Jordan mothers and fathers hold similar levels of attributions and attitudes.

  8. Rhetorical intentionality attribution: its ontogenesis in ordinary conversation.

    Science.gov (United States)

    Bonaiuto, M; Fasulo, A

    1997-12-01

    This paper addresses the assumption that the epistemological dichotomy between reality and its construction is an everyday rhetorical tool children and adults use in their explanations and arguments. Within a discursive psychology perspective, the phenomenon of attribution of rhetorical intentionality (AIR) is theoretically defined developing the notion of prepackaged interest attribution technique (Edwards & Potter, 1992). AIR consists in an explanation of others' discursive moves in terms of a rhetorical-argumentative activity; that is, in terms of a deliberate attempt aimed at construing and presenting reality as a function of the speaker's point of view, perspective and interests, in order to affect the listeners mental state (belief, knowledge, intention) or action. Theoretical links are made to the theory of mind paradigm in the study of intentionality attribution, particularly to the form of life approach which defines intentionality attribution in terms of language games. On this basis, the present study examines the structures and functions of AIR used by children and their parents in everyday conversation. Qualitative discourse analysis of transcripts of 22 dinner conversations from eight Italian families shows explicit and implicit AIR in children from three and a half to seven years of age. Moreover, parents attribute rhetorical intentionality to their children, contributing to their social construction as rhetorical speakers. AIR is used as a rhetorical strategy within disputes and argumentative contexts, often achieving topic closure. Results are discussed with reference to the ontological status of intentionalist talk.

  9. Temporal characteristics of the influence of punishment on perceptual decision making in the human brain

    OpenAIRE

    Blank, H.; Guido, B.; Heekeren, H.R.; Philiastides, M.G.

    2013-01-01

    Perceptual decision making is the process by which information from sensory systems is combined and used to influence our behavior. In addition to the sensory input, this process can be affected by other factors, such as reward and punishment for correct and incorrect responses. To investigate the temporal dynamics of how monetary punishment influences perceptual decision making in humans, we collected electroencephalography (EEG) data during a perceptual categorization task whereby the punis...

  10. Looking without Perceiving: Impaired Preattentive Perceptual Grouping in Autism Spectrum Disorder

    OpenAIRE

    Tiffany A Carther-Krone; Sarah Shomstein; Marotta, Jonathan J.

    2016-01-01

    Before becoming aware of a visual scene, our perceptual system has organized and selected elements in our environment to which attention should be allocated. Part of this process involves grouping perceptual features into a global whole. Individuals with autism spectrum disorders (ASD) rely on a more local processing strategy, which may be driven by difficulties perceptually grouping stimuli. We tested this notion using a line discrimination task in which two horizontal lines were superimpose...

  11. 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...

  12. 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...

  13. 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.

  14. Perceptual Space of Superimposed Dual-Frequency Vibrations in the Hands

    Science.gov (United States)

    Seo, Jeongil; Choi, Seungmoon

    2017-01-01

    The use of distinguishable complex vibrations that have multiple spectral components can improve the transfer of information by vibrotactile interfaces. We investigated the qualitative characteristics of dual-frequency vibrations as the simplest complex vibrations compared to single-frequency vibrations. Two psychophysical experiments were conducted to elucidate the perceptual characteristics of these vibrations by measuring the perceptual distances among single-frequency and dual-frequency vibrations. The perceptual distances of dual-frequency vibrations between their two frequency components along their relative intensity ratio were measured in Experiment I. The estimated perceptual spaces for three frequency conditions showed non-linear perceptual differences between the dual-frequency and single-frequency vibrations. A perceptual space was estimated from the measured perceptual distances among ten dual-frequency compositions and five single-frequency vibrations in Experiment II. The effect of the component frequency and the frequency ratio was revealed in the perceptual space. In a percept of dual-frequency vibration, the lower frequency component showed a dominant effect. Additionally, the perceptual difference among single-frequency and dual-frequency vibrations were increased with a low relative difference between two frequencies of a dual-frequency vibration. These results are expected to provide a fundamental understanding about the perception of complex vibrations to enrich the transfer of information using vibrotactile stimuli. PMID:28081187

  15. Attributional style and life-events.

    Science.gov (United States)

    Rothwell, N; Williams, J M

    1983-06-01

    The study addressed the question of the significance of intervening life-events in linking attributional style and depression. Twenty male subjects who had experienced an uncontrollable event, job redundancy, were compared with 20 controls on measures of attributional style, depression and self-esteem. The reformulated helplessness hypothesis implies that attribution and depression should be correlated only after the uncontrollable event. This was found to be the case for internal--external dimension, providing tentative support for the reformulated helplessness model.

  16. The process of processing: exploring the validity of Neisser's perceptual cycle model with accounts from critical decision-making in the cockpit.

    Science.gov (United States)

    Plant, Katherine L; Stanton, Neville A

    2015-01-01

    The perceptual cycle model (PCM) has been widely applied in ergonomics research in domains including road, rail and aviation. The PCM assumes that information processing occurs in a cyclical manner drawing on top-down and bottom-up influences to produce perceptual exploration and actions. However, the validity of the model has not been addressed. This paper explores the construct validity of the PCM in the context of aeronautical decision-making. The critical decision method was used to interview 20 helicopter pilots about critical decision-making. The data were qualitatively analysed using an established coding scheme, and composite PCMs for incident phases were constructed. It was found that the PCM provided a mutually exclusive and exhaustive classification of the information-processing cycles for dealing with critical incidents. However, a counter-cycle was also discovered which has been attributed to skill-based behaviour, characteristic of experts. The practical applications and future research questions are discussed. Practitioner Summary: This paper explores whether information processing, when dealing with critical incidents, occurs in the manner anticipated by the perceptual cycle model. In addition to the traditional processing cycle, a reciprocal counter-cycle was found. This research can be utilised by those who use the model as an accident analysis framework.

  17. 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.

  18. Key attributes of expert NRL referees.

    Science.gov (United States)

    Morris, Gavin; O'Connor, Donna

    2017-05-01

    Experiential knowledge of elite National Rugby League (NRL) referees was investigated to determine the key attributes contributing to expert officiating performance. Fourteen current first-grade NRL referees were asked to identify the key attributes they believed contributed to their expert refereeing performance. The modified Delphi method involved a 3-round process of an initial semi-structured interview followed by 2 questionnaires to reach consensus of opinion. The data revealed 25 attributes that were rated as most important that underpin expert NRL refereeing performance. Results illustrate the significance of the cognitive category, with the top 6 ranked attributes all cognitive skills. Of these, the referees ranked decision-making accuracy as the most important attribute, followed by reading the game, communication, game understanding, game management and knowledge of the rules. Player rapport, positioning and teamwork were the top ranked game skill attributes underpinning performance excellence. Expert referees also highlighted a number of psychological attributes (e.g., concentration, composure and mental toughness) that were significant to performance. There were only 2 physiological attributes (fitness, aerobic endurance) that were identified as significant to elite officiating performance. In summary, expert consensus was attained which successfully provided a hierarchy of the most significant attributes of expert NRL refereeing performance.

  19. Attractiveness judgments and discrimination of mommies and grandmas: perceptual tuning for young adult faces.

    Science.gov (United States)

    Short, Lindsey A; Mondloch, Catherine J; Hackland, Anne T

    2015-01-01

    Adults are more accurate in detecting deviations from normality in young adult faces than in older adult faces despite exhibiting comparable accuracy in discriminating both face ages. This deficit in judging the normality of older faces may be due to reliance on a face space optimized for the dimensions of young adult faces, perhaps because of early and continuous experience with young adult faces. Here we examined the emergence of this young adult face bias by testing 3- and 7-year-old children on a child-friendly version of the task used to test adults. In an attractiveness judgment task, children viewed young and older adult face pairs; each pair consisted of an unaltered face and a distorted face of the same identity. Children pointed to the prettiest face, which served as a measure of their sensitivity to the dimensions on which faces vary relative to a norm. To examine whether biases in the attractiveness task were specific to deficits in referencing a norm or extended to impaired discrimination, we tested children on a simultaneous match-to-sample task with the same stimuli. Both age groups were more accurate in judging the attractiveness of young faces relative to older faces; however, unlike adults, the young adult face bias extended to the match-to-sample task. These results suggest that by 3 years of age, children's perceptual system is more finely tuned for young adult faces than for older adult faces, which may support past findings of superior recognition for young adult faces.

  20. Physiological and perceptual responses to incremental exercise testing in healthy men: effect of exercise test modality.

    Science.gov (United States)

    Muscat, Kristina M; Kotrach, Houssam G; Wilkinson-Maitland, Courtney A; Schaeffer, Michele R; Mendonca, Cassandra T; Jensen, Dennis

    2015-11-01

    In a randomized cross-over study of 15 healthy men aged 20-30 years, we compared physiological and perceptual responses during treadmill and cycle exercise test protocols matched for increments in work rate - the source of increased locomotor muscle metabolic and contractile demands. The rates of O2 consumption and CO2 production were higher at the peak of treadmill versus cycle testing (p ≤ 0.05). Nevertheless, work rate, minute ventilation, tidal volume (VT), breathing frequency (fR), inspiratory capacity (IC), inspiratory reserve volume (IRV), tidal esophageal (Pes,tidal) and transdiaphragmatic pressure swings (Pdi,tidal), peak expiratory gastric pressures (Pga,peak), the root mean square of the diaphragm electromyogram (EMGdi,rms) expressed as a percentage of maximum EMGdi,rms (EMGdi,rms%max), and dyspnea ratings were similar at the peak of treadmill versus cycle testing (p > 0.05). Ratings of leg discomfort were higher at the peak of cycle versus treadmill exercise (p ≤ 0.05), even though peak O2 consumption was lower during cycling. Oxygen consumption, CO2 production, minute ventilation, fR, Pes,tidal, Pdi,tidal and Pga,peak were higher (p ≤ 0.05), while VT, IC, IRV, EMGdi,rms%max, and ratings of dyspnea and leg discomfort were similar (p > 0.05) at all or most submaximal work rates during treadmill versus cycle exercise. Our findings highlight important differences (and similarities) in physiological and perceptual responses at maximal and submaximal work rates during incremental treadmill and cycle exercise testing protocols. The lack of effect of exercise test modality on peak work rate advocates for the use of this readily available parameter to optimize training intensity determination, regardless of exercise training mode.