Dysfunctions in striatal microstructure can enhance perceptual decision making through deficits in predictive coding.

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Neurobiology

Background:

• Predictive coding, a key brain function, relies on fronto-striatal circuits to anticipate events.
• The impact of striatal microstructural properties on predictive coding remains unclear.
• X-linked dystonia-parkinsonism (XDP) offers a model for studying striatal dysfunction.

Purpose of the Study:

• To investigate how striatal dysfunction, specifically in XDP, affects predictive coding processes.
• To determine if altered striatal microstructure modulates predictive coding and its impact on perceptual decision-making.

Main Methods:

• Utilized high-density electroencephalography (EEG) and source localization in XDP patients and healthy controls.
• Assessed perceptual decision-making performance under distracting conditions.
• Analyzed event-related potentials (ERPs) including mismatch negativity, N2, P3a, and reorientation negativity (RON).

Main Results:

• XDP patients exhibited faster and more accurate perceptual decision-making during distraction compared to controls.
• Electrophysiological data revealed weakened sensory memory and predictive coding (mismatch negativity) in XDP patients.
• Reduced cognitive conflict (N2 ERP) and less pronounced attentional shifting/reorientation (P3a, RON ERPs) were observed in XDP patients.

Conclusions:

• Striosomal dysfunction in XDP is associated with deficits in predictive coding.
• Impaired predictive coding may lead to enhanced perceptual decision-making by minimizing interference.
• These findings suggest a role for striatal imbalances (striosomes vs. matrix) in cognitive processes.