Relationships between intra-individual variability and subclinical psychosis

Area of Science:

• Cognitive Psychology
• Psychopathology
• Neuroscience

Background:

• Elevated intra-individual variability (IIV) in reaction time is a known correlate of psychosis.
• Previous research presents equivocal findings on the specificity of this association with psychotic symptoms and task complexity.

Purpose of the Study:

• To investigate whether associations between IIV and subclinical psychosis are specific to certain psychotic symptoms.
• To determine if these associations differ between simple and complex reaction time tasks.

Main Methods:

• Utilized data from 492 undergraduates.
• Assessed schizotypy and psychotic-like experiences (PLE) via interviews and questionnaires.
• Administered simple reaction time (SRT) and continuous performance task-identical pairs version (CPT-IP) tasks.
• Measured IIV using individual standard deviation and coefficient of variation (ICV).

Main Results:

• Participants reporting PLE showed higher ICV on the CPT-IP.
• Associations between ICV and PLE were specific to paranoid experiences and suspiciousness.
• Weak associations were observed between SRT ICV and PLE.

Conclusions:

• Elevated IIV on complex tasks, particularly the CPT-IP, is associated with specific subclinical psychotic experiences like paranoia.
• Findings suggest IIV may be a more sensitive marker for certain aspects of psychosis than previously thought.
• Future research should employ diverse reaction time tasks to fully explore cognitive control deficits in psychosis.