Background: Theoretical models posit abnormalities in cortico-striatal pathways in two of the most common neurodevelopmental disorders (Developmental dyslexia, DD, and Attention deficit hyperactive disorder, ADHD), but it is still unclear what distinct cortico-striatal dysfunction might distinguish language disorders from others that exhibit very different symptomatology. Although impairments in tasks that depend on the cortico-striatal network, including reinforcement learning (RL), have been implicated in both disorders, there has been little attempt to dissociate between different types of RL or to compare learning processes in these two types of disorders. The present study builds upon prior research indicating the existence of two learning manifestations of RL and evaluates whether these processes can be differentiated in language and attention deficit disorders. We used a two-step RL task shown to dissociate model-based from model-free learning in human learners. Results: Our results show that, relative to neurotypicals, DD individuals showed an impairment in model-free but not in model-based learning, whereas in ADHD the ability to use both model-free and model-based learning strategies was significantly compromised. Conclusions: Thus, learning impairments in DD may be linked to a selective deficit in the ability to form action-outcome associations based on previous history, whereas in ADHD some learning deficits may be related to an incapacity to pursue rewards based on the tasks' structure. Our results indicate how different patterns of learning deficits may underlie different disorders, and how computation-minded experimental approaches can differentiate between them.
|Journal||Behavioral and Brain Functions|
|State||Published - 21 Mar 2023|
Bibliographical noteFunding Information:
This research was supported by grants from the Israel Science Foundation (grant No. 734/22) and the National Institute of Psychobiology in Israel awarded to Yafit Gabay and by Joy Ventures (2020 cycle) awarded to Yafit Gabay and Uri Hertz.
© 2023, The Author(s).
- Attention-deficit/hyperactivity disorder
- Developmental dyslexia
- Model-based vs. Model-free reinforcement learning
- Two-step task
ASJC Scopus subject areas
- Cognitive Neuroscience
- Biological Psychiatry
- Behavioral Neuroscience