Episodic memories bias contextual threat inferences after aerobic and mind-body exercise

Abstract

Background and aim

Contextual threat inference is the process by which latent environmental threat is recognized, a key component of memory which guides decision making. This study sought to interrogate the contribution of episodic memory towards contextual threat inference and determine if acute exercise, an intervention which impacts memory, could magnify the effects of memory on contextual threat inferences.

Methods

Participants (N = 88) underwent two study visits, which each included a contextual threat learning- and inference-task interspersed with 30-min of exercise. Memory probes were embedded during the learning task and manipulated during the inference task. Participants were randomized to complete either moderate- and low-intensity aerobic exercise or yoga and stretching. Linear mixed effect models were used to assess learning outcomes, the impact of episodic memory probes on contextual threat inferences, and the impact of exercise on episodic memory probe recognition and threat inferences.

Results

Participants learned to differentiate contexts based on the unique combinations of conditioned stimuli and threat probabilities. During the threat inference task, recognized episodic memory probes biased contextual threat inferences, but only after participants completed moderate-intensity aerobic exercise or yoga. Recognition of the episodic memory probes was equal across exercise conditions.

Conclusion

These findings provide novel support for the role of episodic memory on contextual threat inferences. There was evidence that moderate-intensity aerobic exercise and yoga impact associative ties between episodic memories and context. These results support neurocomputational models which integrate episodic memory with reinforcement learning and inform the cognitive processes through which exercise may impact contextual threat inference.