Shaul-Rom-2019

ABSTRACT

The present study compared the semantic processing of pictures and words by dyslexics to that of typical readers utilizing the electro-physiological (ERP) technique during a semantic categorization decision task. ERPs of 40 university students, 20 typical readers and 20 dyslexic readers were recorded while they participated in a categorization decision task. The subjects were presented with two kinds of stimuli―words and pictures. Results revealed longer reaction times in response to words as compared to pictures in both groups. Electrophysiological measures revealed differences in amplitudes and latencies of ERP components in addition to differences in the mean activity. The results illustrated that the differences between processing words and processing pictures were manifested in timing and in the brain areas involved in the tasks. It also illustrated that although dyslexic and typical readers displayed equal ability to read and understand familiar words, dyslexics could not perform as quickly as typical readers. The semantic domain may be one of the compensatory mechanisms which help compensated dyslexic readers reach and succeed in the higher education system.

 

Excerpts:

 

This study used behavioral and electro-physiological (ERP) measures to compare the semantic processing with verbal (words) and nonverbal (pictures) stimuli of dyslexic readers to that of regular readers. The aim of the study was to determine whether there are differences between the processing words and the processing of pictures in both timing and in brain areas and whether there are differences in brain activity between dyslexic students and typical readers while processing meaning from words and from pictures.

 

These results may imply that children should be taught words together with their picture; this may strengthen their representation in the mental lexicon and help retrieve the words faster, in fact maybe vocabulary should be taught with pictures, this may broaden the child’s vocabulary in a better and easier way.

 

The behavioral results of reaction time illustrated differences between RT for words and pictures which was larger among the dyslexics as compared to typical readers, meaning that the dyslexics were slower only in words and not in pictures. In contrast, no significant differences or interaction in accuracy between the groups was found.

 

Contrary to our hypothesis, behavioral and electrophysiological results showed no differences between dyslexic students and typical readers while processing words and pictures, except for slowness of the whole process among dyslexic while processing words.

 

The contribution of the present study to the reading research and dyslexia lies on its focus on the semantic processes that help us to comprehend the meaning from written words and objects. The basic semantic domain seems to be intact among the compensated dyslexic students and it is important to strengthen the reliance on it. Berends & Reitsma (2006) suggested that it is important for fluent reading among disabled readers to make them think about the meaning of words (semantics) they are reading and practicing.