# The Roles of Rule Type and Word Term in the Deductive Reasoning of Adults with and without Dyslexia

## TL;DR

This study explores how adults with and without dyslexia perform on a verbal reasoning task, finding that reasoning accuracy is influenced more by rule type and word properties than by dyslexia status.

## Contribution

The study introduces the Wason selection task to dyslexia research and identifies the impact of rule type and word imageability on reasoning performance.

## Key findings

- Participants were most accurate with the rule type 'If p, then not q' and least accurate with 'If p then q'.
- Highly imageable words improved reasoning accuracy regardless of dyslexia status.
- Dyslexia did not interact with rule type or word term type in affecting reasoning performance.

## Abstract

Despite its importance to everyday functioning, reasoning is underexplored in developmental dyslexia. The current study investigated verbal deductive reasoning on the Wason selection task, not previously used in dyslexia research despite its well-established pedigree. Reasoning rule was manipulated, with the conditional rules varying in the logical values presented. The word frequency and imageability of the word terms was also manipulated. Twenty-six adults with dyslexia and 31 adults without dyslexia completed Wason selection task problems. No group difference in reasoning accuracy or completion time was found. However, the participants were most accurate when reasoning with the rule type “If p, then not q” and least accurate with the rule type “If p then q”. More trials were also answered correctly when the word terms were highly imageable but of average word frequency. These findings are in line with the general reasoning literature. Dyslexia status did not interact with either rule type or word term type. The study expands upon previous research by testing verbal deductive reasoning in dyslexia, highlighting the role of imageability in facilitating reasoning performance for all, regardless of the presence or absence of dyslexia. Implications for the design of educational materials are considered.