Fig 8. Illustrative representation of the results from the extinction portion of the behavioural testing for STD and IMP animals; blue bars represent the initial testing day and white bars represent the scores after the 3rd consecutive day of no reward in the 5 choice serial reaction task.
In this task, rats are no longer rewarded for completing the task as previously trained; therefore learning would entail switching strategies and reducing the number of correct nose pokes. The upper panels (A & B) demonstrate the number of correct lights with STD-shams learning the task quicker; the middle panels (C & D) show that the average number of impulsive nose-pokes (premature or inappropriate) decreased when the reward was removed; and finally (E & F) represent the number of lights that the rats chose to ignore with STD-shams again outperforming all other groups (α significant effect of IMP at Day 1, β significant effect of IMP at Day 3, x significant effect of mTBI, * significant effect of testing period, all p < .05).