Learning from the Good or the Bad: Understanding the Complex Impact of Stress on Feedback-Based Learning

Stress is a physical, mental, or emotional response to events that cause bodily or mental tension. It arises from any situation or thought that makes you feel frustrated, angry, or nervous. Stress is your body’s way of responding to any kind of demand or threat. When faced with a challenge or danger, the body kicks into gear, flooding the body with hormones that elevate heart rate, increase blood pressure, boost energy, and prepare it to deal with the problem. Stress has profound implications on both behavioral and health outcomes. It’s associated with various detrimental effects including cardiovascular diseases and mental disorders. Feedback-based learning, integral to everyday functioning, involves decision-making based on previous positive or negative feedback. Previous research has highlighted that stress can affect feedback processing through the activation of the hypothalamic–pituitary–adrenal axis and changes in neural activities, particularly in areas such as the prefrontal cortex and striatal circuits. Under stress, individuals might respond better to positive feedback. Stress narrows focus, and positive reinforcement can help in directing this focused attention towards beneficial learning behaviors. Conversely, stress may make individuals more sensitive to negative feedback. This heightened sensitivity can either lead to a more careful and adjusted approach to learning or cause discouragement and avoidance behaviors, depending on the individual’s coping mechanisms and resilience. A new study published in the Journal Brain Sciences, Assistant Professor Xiao Yang from Old Dominion University in collaboration with PhD candidate Brittany Nackley, and Professor Bruce Friedman from Virginia Polytechnic Institute and State University, conducted a laboratory experiment to investigate how different types of stress affect feedback-based learning. Their primary aim was to differentiate between the impacts of physical and psychosocial stressors on this type of learning.

The team recruited 96 participants, mostly college students, and divided them into two groups. Each group was subjected to a different type of stressor: one group underwent a physical stressor (Cold Pressor Task, CPT), where in this task, participants immersed their foot in cold water, creating a physical stress response and the other faced a psychosocial stressor (Mental Arithmetic Task, MAT) where this task involved performing a challenging mental arithmetic exercise in a socially evaluative context, inducing psychosocial stress. The team measured electrocardiography and blood pressure to assess Cardiovascular Reactivity (CVR) as a physiological indicator of the stress response. Moreover, participants rated their emotional response to the stressors. Before and after the stressors, participants engaged in a probabilistic learning task, which measured their ability to learn from positive and negative feedback. Indeed, using a between-group pretest–posttest design, it effectively distinguishes between physical (cold pressor task) and psychosocial (mental arithmetic task) stressors. The use of cardiovascular indices and self-rated valence as stress response metrics offers a novel lens through which to view stressor impacts.

The authors found no significant difference in the impact of physical (CPT) and psychosocial (MAT) stressors on feedback-based learning. This suggests that the type of stressor may not be as critical in determining its impact on this kind of learning. Interestingly, CVR and the emotional valence of the stressors did influence learning outcomes, but differently. Higher CVR was associated with improved accuracy in tasks involving positive feedback (Go accuracy), while the emotional valence of the stressors influenced tasks involving negative feedback (No-go accuracy). These findings suggest that the relationship between stress and learning is multifaceted. Both physiological responses (like CVR) and psychological factors (such as emotional reactions to stress) play a role in how stress affects learning. This highlights the need to consider multiple pathways through which stress can modulate cognitive processes.

One of the critical findings of the study is that while the effects of physical and psychosocial stressors on feedback processing were not significantly different, CVR and emotional valence influenced learning outcomes. This finding highlights the multifaceted nature of stress and its impact on learning, suggesting that stress-modulated feedback-based learning involves multiple pathways. The link between CVR and reward sensitivity, in particular, opens new avenues for understanding the physiological basis of stress impacts on cognitive processes. The researchers’ findings have significant clinical implications because it teaches us how stress affects learning and decision-making, which is important for addressing mental health issues and aging-related cognitive decline.