Dyslexia: Still Not a Neurodevelopmental Disorder.

Area of Science:

• Neuroscience
• Developmental Psychology
• Education

Background:

• The common view posits brain abnormalities in children with reading difficulties.
• Dyslexia is often debated as a neurodevelopmental disorder due to its impact on quality of life and observed brain differences.
• The definition of neurodevelopmental disorder requires evidence of disrupted neurodevelopment or a brain fault.

Purpose of the Study:

• To evaluate the evidence supporting dyslexia as a neurodevelopmental disorder.
• To critically assess the claims linking brain differences to reading difficulties.
• To determine if current neurological or neuroscientific input is relevant for dyslexia assessment and remediation.

Main Methods:

• Literature review and critical analysis of existing research on dyslexia.
• Examination of the definition and criteria for neurodevelopmental disorders.
• Evaluation of group differences in brain structure/function in relation to individual reading ability.

Main Results:

• No credible evidence was found to support dyslexia as a neurodevelopmental disorder.
• Observed brain differences between reading groups do not equate to a 'brain fault' or abnormal development.
• The concept of 'typicality' in brain function is not established, making claims of atypicality unfounded.

Conclusions:

• The claim that dyslexia is a neurodevelopmental disorder lacks a credible foundation.
• Group differences in brain characteristics do not confirm individual neurodevelopmental deficits.
• Current neurological and neuroscientific approaches offer no clear benefit for dyslexia assessment and remediation.