Female rats retain goal-directed planning of action sequences after acute stress despite changes in planning structure and action sequence execution

When making decisions under stress, organisms tend to deliberate less and rely on automatic habits. Prior investigation into the influence of stress on decision-making has primarily viewed goal-direction and habit as independent and competitive sources of control in static environments. The effects of acute stress on the integration of goal-direction and habit in hierarchical planning to solve dynamic tasks remain unclear. Here, our aim was to assess whether stress prompted the usage of habitual action sequences over the selection of discrete goal-directed actions in a serial decision task. We trained 16 female Long Evans rats in a two-stage binary choice task and performed two probe tests, one following acute restraint stress and one under control conditions, to identify how stress affected higher-level planning of behavior and intermediate action structures. We found that under both stressed and control conditions, rats exhibited goal-directed planning of habitual action sequences. However, following stress, rats showed a greater tendency to reiterate action sequences independent of reinforcement, indicating that stress may induce an aversion to exploration in action planning. Stress also increased the latency between responses – degrading action sequence integrity despite conserving their overall structure and performance. Taken together, these findings suggest that although acute stress does not disrupt the overall macrostructure of behavior in two-stage decision-making, it does alter the microstructure of goal-directed and habitual control individually. Further, these results imply that the extent to which stress impairs goal-direction in female rats may depend on the incentive structure and attentional demands of the decision environment.