Individuals with Attention-Deficit/Hyperactivity Disorder (ADHD) often show impairments in cognitive inhibition, which may affect their ability to suppress incorrect initial interpretations during sentence comprehension. However, little is known about how these inhibitory difficulties shape online syntactic processing, particularly when readers encounter temporarily ambiguous Garden-Path structures. This preregistered eye-tracking experiment investigates these mechanisms in adults with clinically verified ADHD.

In a 2 × 2 mixed design, N = 100 participants (50 ADHD, 50 controls) read validated German Garden-Path sentences containing genitive or dative ambiguities (Van Kampen, 2001), along with non-ambiguous counterparts and 24 fillers. Participants read self-paced while high-resolution eye movements were recorded. Two key dependent measures were collected: (a) total reading time per sentence as an index of syntactic integration difficulty, and (b) reanalysis processes quantified as regression-related saccades per second, standardized by reading duration.

Based on theoretical accounts of reduced inhibitory control in ADHD, we hypothesized longer reading times and increased regression behavior for ambiguous sentences in the ADHD group relative to controls. Data collection has been completed, and statistical analyses are currently being performed. This study aims to provide further insights into the cognitive mechanisms underlying sentence comprehension in ADHD.