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Danielle Ropar

Publications and source records attributed to Danielle Ropar.

4 recordsLinked to original sources

Sorting preference in children with autism: the dominance of concrete features.

The current study investigates preference to sort objects on the basis of either concrete or abstract features in children with and without autism. Participants were asked to sort a set of books into two groups that could be differentiated according to concrete (color, size) or abstract criteria (category membership: sports/games). The results showed that those with autism, unlike controls, were significantly more likely to sort according to a concrete criterion. In a further phase of testing, those with autism still did not sort according to abstract criteria, even when this was the only basis for sorting systematically. The findings are interpreted as evidence for a preference in autism to process concrete over abstract features of stimuli.

Adolescent↗

The impact of meaning and dimensionality on copying accuracy in individuals with autism.

Weak Central Coherence (Frith, 1989) predicts that, in autism, perceptual processing is relatively unaffected by conceptual analysis. Enhanced Perceptual Functioning (Mottron & Burack, 2001) predicts that the perceptual processing of those with autism is less influenced by conceptual analysis only when higher-level processing is detrimental to task performance. This research tested these theories using a copying task where one conceptual aspect enhances accuracy (meaningfulness) and another hinders it (three-dimensionality). Children and adolescents with and without autism copied meaningful and non-meaningful two-dimensional and three-dimensional line drawings. Drawing accuracy and strategy (global/local) were assessed. Participants with autism were less affected by dimensionality but not meaningfulness, apparently supporting EPF. Effects of dimensionality did not relate to drawing strategy, also contrary to WCC.

Adolescent↗

How perception impacts on drawings.

In 3 experiments the authors investigate how errors in perception produce errors in drawings. In Experiment 1, when Shepard stimuli were shown as a pair of tables, participants made severe errors in trying to adjust 1 part of the stimulus to match the other. When the table legs were removed, revealing a pair of parallelograms with minimal perspective cues, the illusion was weaker. The authors predicted that participants would err when drawing the table but not the parallelogram stimuli. The results of Experiment 2 support the prediction and establish a direct link between degree of perceptual distortion of the table stimuli and the severity of error in drawing. When drawing only the right-hand part of the figure, participants also erred to a greater degree in drawing the table than the parallelogram (Experiment 3). Collectively, the results suggest that perceptual distortion is linked with errors in drawing the table stimuli.

Adult↗

Shape constancy in autism: the role of prior knowledge and perspective cues.

BACKGROUND: Evidence suggests that individuals with autism may not attend to contextual information (conceptual or perceptual) when processing stimuli (Frith 1989; Shah & Frith, 1983). METHOD: We investigated the role of prior knowledge and perspective cues when judging the shape of a slanted circle in individuals with and without autism. Individuals adjusted a shape on a computer screen to appear the same as a slanted circle. RESULTS: Participants in all groups (autistic, moderate learning difficulties, children aged 9 years and adults) exaggerated circularity. Strikingly, however, individuals with autism were unique in exaggerating circularity significantly far less when perspective cues surrounding the slanted circle were eliminated. Prior knowledge that the shape was a slanted circle provoked a strong exaggeration effect in participants without autism, but not in those with autism. CONCLUSIONS: Perhaps classifying the stimulus as a 'circle' was sufficient to provoke a strong exaggeration effect in those without (but not with) autism. In this domain, we show that perception in autism may be less influenced by prior knowledge, and therefore less 'top-down'.

Adolescent↗