Word length effect in early reading and in developmental dyslexia

Area of Science:

• Developmental Psychology
• Cognitive Neuroscience
• Linguistics

Background:

• Reading development involves acquiring efficient word recognition strategies.
• Italian, an orthographically transparent language, facilitates early development of lexical reading strategies in typical readers.
• Developmental dyslexia is characterized by persistent difficulties in reading acquisition.

Purpose of the Study:

• To investigate vocal reaction times (RTs) in Italian dyslexic children compared to age-matched proficient readers.
• To examine the developmental trajectory of reading strategies in relation to age and reading ability.
• To explore the underlying processing differences between dyslexic and typical readers in an Italian context.

Main Methods:

• Vocal reaction times were measured during single-word reading tasks.
• Participants included Italian dyslexic children and three groups of control children across elementary school grades.
• Reading ability was assessed using standard reading procedures.

Main Results:

• Vocal RTs in control participants improved and became less sensitive to word length with age, with significant changes between first and second graders.
• Dyslexic children demonstrated significantly slower vocal RTs and higher error rates compared to their peer controls.
• The performance of dyslexic children resembled that of first-grade controls, irrespective of their actual grade level.

Conclusions:

• Normal Italian readers develop lexical reading strategies early, benefiting from the language's transparent orthography.
• Dyslexic children appear to struggle in acquiring lexical processing, continuing to rely on less efficient sub-lexical procedures.
• These findings highlight distinct reading processing pathways in developmental dyslexia, even in transparent orthographic systems.