Biomedical subjects

Christine Deruelle

Publications and source records attributed to Christine Deruelle.

10 recordsLinked to original sources

PubMed2006

Global and configural visual processing in adults with autism and Asperger syndrome.

This study was designed to explore how adults with autism and Asperger syndrome (ASD) would visually process compound figures. They were tested in two tasks, one involving hierarchical global/local stimuli, the other involving face-like or geometrical stimuli where the processing of the inter-elemental spatial relationships was emphasized. Adults with ASD showed, like controls, a preference for the global level of the hierarchical stimuli. With the stimuli involving inter-elemental spatial relationship manipulations, the adults with ASD showed a preference for local elements, whereas controls did not show a preference. This supports earlier findings from children with ASD, suggesting that though individuals with autism may process global aspects of stimuli in priority, they tend to specific aspects in stimuli containing both local and configural elements.

Adolescent↗

PubMed2006

Laterality in persons with intellectual disability. I--do patients with trisomy 21 and Williams-Beuren syndrome differ from typically developing persons?

Persons with trisomy 21 (T21) and Williams-Beuren syndrome (WBS) have different brain abnormalities which may affect manual laterality. We assessed 45 persons with T21 and 34 with WBS (mean age 13) and 81 typically developing children (TD). Manual laterality was assessed with a fifteen-item task administered two times, and Bishop's card-reaching task. We found more left-handers in the T21 group compared to the other two groups. Inconsistent laterality was higher in the two groups with genetic diseases than in the TD group. For Bishop's test, both T21 and WBS participants were less right-oriented than the TD group. They displayed different response patterns in midline crossing when reaching for the cards, but did not display more midline crossing inhibition than the TD group. Is atypical handedness linked to specific genetic syndromes and, more specifically for persons with T21, to the trisomy of some of the genes?

Aging↗

PubMed2006

Amodal completion by baboons (Papio papio): contribution of background depth cues.

Four baboons (Papio papio) were tested in a computerized two-alternative forced choice task in which partially occluded graphic stimuli were shown either on linear perspective backgrounds depicting a corridor or on uniformly black backgrounds. The results indicated that baboons complete partly occluded stimuli and that amodal completion is facilitated by the display of pictorial background depth cues. Inter-individual differences emerged in the ability to extrapolate three-dimensional information from two-dimensional visual information.

Animals↗

PubMed2006

Laterality in persons with intellectual disability II. Hand, foot, ear, and eye laterality in persons with Trisomy 21 and Williams-Beuren syndrome.

Laterality (hand, foot, ear, and eye) was assessed in participants with Trisomy 21 (62) and Williams-Beuren syndrome (WBS) (39). Handedness was also assessed in a card reaching task. The comparison group included 184 typically developing persons. Two independent age sub-groups were formed: 7 to 10 years old and 11 to 34 years old. We confirmed previous data: individuals with T21 were more frequently left- or mixed-handed than typically developing persons; individuals with WBS had intermediate scores. The two groups with genetic disorders had less right foot preference. Manual and foot inconsistencies characterized both groups with genetic disorders. Cross hand-foot preference was lower in the typically developing group. Differences in IQ levels did not correlate with differences in laterality scores. Overall laterality profiles were not the same in the two groups with genetic disorders: the greatest differences were observed between typically developing persons and persons with Trisomy 21.

Adolescent↗

PubMed2005

Do children with Williams syndrome fail to process visual configural information?

Configural visual abilities in thirteen children with Williams syndrome (WS) compared to 13 children matched on mental age and 13 children matched on chronological age. Configural abilities were tested through four tasks (1) Silhouette (2) Fragmented (3) Mooney and (4) overlapping figures. In the first three tasks, it was necessary to take into account the global information, as the identification of the figures could not be established through a local analysis. In the fourth task, the global configuration of the display had to be ignored. Configural skills seem appropriate in the WS population. A possible dissociation between perceptual and visuo-constructive configural competences is discussed.

Child↗

PubMed2005

Global and local music perception in children with Williams syndrome.

Musical processing can be decomposed into the appreciation of global and local elements. This global/local dissociation was investigated with the processing of contour-violated and interval-violated melodies. Performance of a group of 16 children with Williams syndrome and a group of 16 control children were compared in a same-different task. Control participants were more accurate in detecting differences in the contour-violated than in the interval-violated condition while Williams syndrome individuals performed equally well in both conditions. This finding suggests that global precedence may occur at an early perceptual stage in normally developing children. In contrast, no such global precedence is observed in the Williams syndrome population. These data are discussed in the context of atypical cognitive profiles of individuals with Williams syndrome.

Acoustic Stimulation↗

PubMed2004

Categorizing facial identities, emotions, and genders: attention to high- and low-spatial frequencies by children and adults.

Three age groups of participants (5-6 years, 7-8 years, adults) matched faces on the basis of facial identity. The procedure involved either low- or high-pass filtered faces or hybrid faces composed from two faces associated with different spatial bandwidths. The comparison stimuli were unfiltered faces. In the three age groups, the data indicated a significant bias for processing of low-pass information in priority. In a second task, participants were asked to identify the emotion (smiling or grimacing) or gender (male or female) of hybrid high-pass/low-pass faces. Opposite results emerged in the two tasks irrespective of the age group; the gender discrimination task indicated a bias for low-pass information, and the emotion task indicated a bias for high-pass information. These differences suggest independent processing routes for functionally different types of information such as emotion, gender, and identity. These routes are already established by 5 years of age.

Adolescent↗

PubMed2004

Spatial frequency and face processing in children with autism and Asperger syndrome.

Two experiments were designed to investigate possible abnormal face processing strategies in children with autistic spectrum disorders. A group of 11 children with autism was compared to two groups of normally developing children matched on verbal mental age and on chronological age. In the first experiment, participants had to recognize faces on the basis of identity, emotion, gaze direction, gender, and lip reading. All aspects of face processing, except for identity matching, were deficient in the autistic population compared with controls. In the second study, children had to match faces on either high-(i.e., local facial features) or low-spatial frequency information (i.e., global configuration of faces). Contrary to the control subjects, children with autism showed better performance when using high rather than low spatial frequency, confirming face-processing peculiarities in this population.

Adolescent↗

PubMed2003

Inner and outer face perception in children with autism.

Possible peculiarities in face perception in the autistic population were explored through two experiments. Fourteen autistic children (mean age=10 years 1 month) were individually matched to verbal mental age (VMA) and chronological age (CA) subjects. In a first experiment, subjects were to match faces on the basis of either their outer (hair, chin, ears) or their inner (eyes, nose, mouth) aspects. Autistic children performed equally well in both conditions, while VMA-matched children performed better in the outer than the inner part condition. In a second experiment, chimeric faces consisting of the outer part of an individual's face and the inner part of another individual's face were presented to the subjects. None of the groups showed a preference for neither the outer nor the inner part of the face in this condition. Results were discussed in terms of the existence of a local visual processing strategy in this population.

Asperger Syndrome↗

PubMed2002

Perception of pictorial eye gaze by baboons (Papio papio).

Pictorial faces looking left or right were presented to baboons (Papio papio) before the display of a target letter in the left or right hemifield of a monitor screen. Baboons had to provide go or no-go responses taking into account the identity of the target letter. The 1st 6 experiments showed no reliable effect of eye gaze on discrimination speed, using either schematic gazes or pictures of real gazes. Experiment 7 showed that eye gazes facilitated target processing when eye cues were perfect predictors of target location. Findings suggest that baboons do not spontaneously process eye-gaze direction but can learn to do so if the gaze has a predictive value. Implications of these findings on baboons' perspective-taking abilities are discussed.

Animals↗