INS NYC 2024 Program

Poster	Poster Session 10 Program Schedule 02/17/2024 09:00 am - 10:15 am Room: Shubert Complex (Posters 1-60) Poster Session 10: Neurodevelopmental \| Congenital Conditions Final Abstract #6 Part-Based Processing of Visual Objects May be Less Efficient in Developmental Dyslexia Susana Araújo, Faculty of Psychology, University of Lisbon, Lisbon, Portugal Diana Dias, Faculty of Psychology, University of Lisbon, Lisbon, Portugal Inês Bramão, Faculty of Psychology, University of Lund, Lund, Sweden Category: Autism Spectrum Disorders/Developmental Disorders/Intellectual Disability Keyword 1: dyslexia Keyword 2: cognitive processing Objective: Visual word recognition heavily relies on letter-based word identification, largely influenced by experience. Decomposition of the word into parts predominates despite readers expertise at recognizing thousands of written words, however, this processing mechanism seems to be less efficient in people with developmental dyslexia. Here, we examined whether such difficulty extends to other visual categories beyond written words, specifically, whether dyslexic readers may be impaired at part-based processing of non-linguistic visual objects. A relation is predicted because word and object recognition engage overlapping cognitive and neural underpinnings. Participants and Methods: Twenty-seven adults with a formal dyslexia diagnosis (Mage= 23.0 yrs.; 17 females) and 36 control, typical readers (Mage= 23.4 yrs.; 26 females) participated in this study. Groups were matched on years of education, age, and nonverbal IQ, but dyslexic participants scored below the control group on reading fluency for single (non)words. They were tested on a visual naming task with line drawings of familiar objects, that could be recognized either from their global shape alone (e.g., a chair) or based on internal features or constituent parts (e.g., a zebra), and were presented in two visibility conditions, blurred and non-blurred. Results: Object naming accuracy was high and equivalent in the two groups. On response times, a robust three-way interaction indicated that blurring of objects was more detrimental for dyslexic readers’ performance than it was for typical readers, but only for those objects in which several parts/features must be encoded for recognition. Both groups were equally fast at naming “global shape” objects regardless of their visibility. Conclusions: The current results suggest that naming objects whose recognition is mediated by encoding specific features or components poses a different challenge to dyslexic people than objects for which global shape processing suffices. This occurs even though dyslexics are as accurate in naming these objects as typical readers, who do not show such a distinction, and visual ambiguity is kept constant in the two object classes. We speculate that dyslexic readers are disadvantaged at using specific visual processing mechanisms, in particular that part- or feature-based processing of visual objects may be suboptimal in these individuals. This interpretation aligns with recent work testing different non-linguistic stimuli (faces, houses).

Poster

02/17/2024
09:00 am - 10:15 am
Room: Shubert Complex (Posters 1-60)

Poster Session 10: Neurodevelopmental | Congenital Conditions

Final Abstract #6

Part-Based Processing of Visual Objects May be Less Efficient in Developmental Dyslexia

Susana Araújo, Faculty of Psychology, University of Lisbon, Lisbon, Portugal
Diana Dias, Faculty of Psychology, University of Lisbon, Lisbon, Portugal
Inês Bramão, Faculty of Psychology, University of Lund, Lund, Sweden

Category: Autism Spectrum Disorders/Developmental Disorders/Intellectual Disability

Keyword 1: dyslexia
Keyword 2: cognitive processing

Objective:

Visual word recognition heavily relies on letter-based word identification, largely influenced by experience. Decomposition of the word into parts predominates despite readers expertise at recognizing thousands of written words, however, this processing mechanism seems to be less efficient in people with developmental dyslexia. Here, we examined whether such difficulty extends to other visual categories beyond written words, specifically, whether dyslexic readers may be impaired at part-based processing of non-linguistic visual objects. A relation is predicted because word and object recognition engage overlapping cognitive and neural underpinnings.

Participants and Methods:

Twenty-seven adults with a formal dyslexia diagnosis (Mage= 23.0 yrs.; 17 females) and 36 control, typical readers (Mage= 23.4 yrs.; 26 females) participated in this study. Groups were matched on years of education, age, and nonverbal IQ, but dyslexic participants scored below the control group on reading fluency for single (non)words. They were tested on a visual naming task with line drawings of familiar objects, that could be recognized either from their global shape alone (e.g., a chair) or based on internal features or constituent parts (e.g., a zebra), and were presented in two visibility conditions, blurred and non-blurred.

Results:

Object naming accuracy was high and equivalent in the two groups. On response times, a robust three-way interaction indicated that blurring of objects was more detrimental for dyslexic readers’ performance than it was for typical readers, but only for those objects in which several parts/features must be encoded for recognition. Both groups were equally fast at naming “global shape” objects regardless of their visibility.

Conclusions:

The current results suggest that naming objects whose recognition is mediated by encoding specific features or components poses a different challenge to dyslexic people than objects for which global shape processing suffices. This occurs even though dyslexics are as accurate in naming these objects as typical readers, who do not show such a distinction, and visual ambiguity is kept constant in the two object classes. We speculate that dyslexic readers are disadvantaged at using specific visual processing mechanisms, in particular that part- or feature-based processing of visual objects may be suboptimal in these individuals. This interpretation aligns with recent work testing different non-linguistic stimuli (faces, houses).