Large-N Rat Data Enables Phenotyping of Risky Decision-Making: A Retrospective Analysis of Brain Injury on the Rodent...

Area of Science:

• Neuroscience
• Behavioral Science
• Decision Science

Background:

• Brain injuries significantly alter decision-making processes.
• Individuals with brain injuries often exhibit suboptimal and risky choices.
• Altered sensitivity to outcomes is a potential mechanism underlying these behavioral changes.

Purpose of the Study:

• To investigate how traumatic brain injury (TBI) affects decision-making in rats.
• To assess changes in sensitivity to overall contingencies, immediate outcomes, and general choice phenotypes after TBI.
• To identify distinct decision-making phenotypes and the impact of TBI on them.

Main Methods:

• Compiled and harmonized data from four studies using the Rodent Gambling Task (RGT).
• Evaluated overall sensitivity using the matching law.
• Assessed immediate outcome sensitivity by analyzing choice switching after wins or losses.
• Identified choice phenotypes using k-means clustering.

Main Results:

• TBI rats showed reduced sensitivity to overall outcomes and a bias toward riskier choices.
• A significant reduction in the tendency to repeatedly choose an option was observed in TBI rats.
• Clustering revealed five decision-making phenotypes, with TBI reducing membership in the 'optimal' type.
• No significant difference in win- or loss-specific sensitivity was found.

Conclusions:

• TBI reduces sensitivity to behavioral contingencies.
• TBI-induced decision-making deficits are not characterized by indiscriminate responding but by suboptimal preferences and increased choice switching.
• Future treatments for TBI should address these specific behavioral changes in decision-making.