Implicit and Explicit Sequence Learning in Adults With Developmental Language Disorder.

Area of Science:

• Neuroscience
• Developmental Psychology
• Speech and Language Pathology

Background:

• Developmental language disorder (DLD) affects language skills in approximately 7% of the population.
• Procedural learning, particularly via serial reaction time (SRT) tasks, is used to model DLD.
• Existing SRT paradigms conflate implicit and explicit learning, complicating DLD research.

Purpose of the Study:

• To investigate implicit and explicit procedural learning in adults with DLD.
• To differentiate learning components in SRT tasks for individuals with DLD.
• To test the hypothesis that DLD affects implicit but not explicit learning.

Main Methods:

• Fifty adults (25 with DLD, 25 typically developing) completed implicit and explicit SRT tasks.
• Participants learned visually presented 10-element sequences.
• Evaluated sequence learning, error rates, and explicit sequence recall.

Main Results:

• Both groups demonstrated similar sequence learning abilities across implicit and explicit tasks.
• Individuals with DLD exhibited higher error rates.
• Adults with DLD had significantly poorer explicit recall of learned sequences.

Conclusions:

• Sequence learning appears intact in adults with DLD.
• Explicit learning and motoric response aspects are impaired in DLD.
• Findings support a neurobiological model of DLD, highlighting specific explicit learning deficits.