Loss of Cognitive Flexibility Practice Effects in Female Rats Exposed to Simulated Space Radiation

Area of Science:

• Space science
• Neuroscience
• Radiation biology

Background:

• Astronauts face health risks from space radiation.
• Previous studies show radiation affects male rodent cognition.
• Limited data exists on radiation's impact on female rodent cognitive flexibility.

Purpose of the Study:

• To determine the effects of simulated galactic cosmic radiation (GCRSim) and helium-ion (4He) exposure on female Wistar rats' cognitive flexibility.
• To assess performance in constrained (attentional set shifting - ATSET) and unconstrained cognitive flexibility tasks.

Main Methods:

• Female Wistar rats were exposed to GCRSim or 4He ions.
• Cognitive flexibility was assessed using the ATSET task, including compound discrimination (CD) and compound discrimination reversal (CDR) stages.
• Performance metrics, including time to completion and attempts to reach criterion, were analyzed pre- and post-exposure.

Main Results:

• GCRSim exposure impaired performance in the ATSET CD stage, increasing completion time.
• Both 4He and GCRSim exposure reduced the ability to complete the CDR stage, requiring more attempts.
• Radiation exposure eliminated practice effects and increased anterograde interference in the ATSET task.

Conclusions:

• Female rats are susceptible to radiation-induced decrements in cognitive flexibility (ATSET task).
• Radiation exposure negatively impacts performance by impairing task switching and increasing interference.
• Findings suggest potential cognitive challenges for astronauts exposed to space radiation.