Sex-dependent effects on tasks assessing reinforcement learning and interference inhibition

Area of Science:

• Neuroscience
• Cognitive Psychology
• Human Behavior

Background:

• Sex steroids influence the prefrontal cortex (PFC), potentially leading to sexually differentiated cognitive functions.
• Previous research indicated male advantages in complex reinforcement learning, but specific contributing factors remain unclear.

Purpose of the Study:

• To investigate sex differences in response inhibition and valenced feedback processing within reinforcement learning tasks.
• To identify specific cognitive components underlying previously observed sex differences in reinforcement learning.

Main Methods:

• Healthy young adults (90 males, 86 females) matched for general intelligence participated.
• Participants completed the Probabilistic Selection Task (PST), a Simon task, and the Stop-Signal task.
• Performance metrics included accuracy, reaction time, and inhibition control.

Main Results:

• Females showed higher accuracy than males in learning from positive feedback on the PST.
• Males exhibited faster reaction times than females on the Simon task, particularly with incongruent stimuli.
• No significant sex difference was detected in Stop-Signal reaction time, indicating similar response inhibition.

Conclusions:

• Findings suggest a potential sex difference in processing valenced feedback, with females excelling in positive feedback learning.
• Preliminary evidence supports sex-based variations in interference inhibition, as shown by Simon task performance.
• These results contribute to understanding the neurobiological underpinnings of cognitive sex differences in the prefrontal cortex.