A review on exploration-exploitation trade-off in psychiatric disorders.

Balancing exploration and exploitation is a crucial aspect of adaptive decision-making, but psychiatric disorders can disrupt this balance in various ways, shedding light on their neurocognitive roots and guiding targeted interventions. In this systematic review, we aimed to delineate potential exploration-exploitation impairments across psychiatric disorders. Through a thorough search on PubMed, we identified forty-six relevant studies employing tasks probing exploration-exploitation balances, which we synthesized to reveal distinct patterns. These disorders are clustered into three categories: addictive patterns, emotional/cognitive disturbances, and neurological (neurodevelopmental and neurodegenerative) disorders. Our findings show that anxiety and mood disorders often enhance exploratory behaviors, while depression impact decision stability and reward sensitivity. In contrast, schizophrenia, OCD (Obsessive-Compulsive Disorder), and ADHD (Attention-Deficit/Hyperactivity Disorder) are characterized by excessive switching and difficulties in balancing exploration and exploitation, leading to impaired learning and adaptability. Additionally, disorders with addictive-like features disrupt optimal decision-making strategies by either heightening exploration or causing maladaptive persistence, thus skewing the balance away from effective decision-making. Individuals exhibiting addiction-like or compulsive behaviors often demonstrate imbalances in the explore-exploit trade-off, resulting in suboptimal decision-making characterized by reduced exploration, flawed foraging strategies, and impulsive or perseverative choices despite adverse outcomes. This suggests that such disorders may originate from dysfunctional foraging processes applied to decision-making. In sum, different patterns of exploration-exploitation balance in different disorders are crucial in understanding the difficulties in learning and decision making of neuropsychiatric disorders. This suggests that such disorders may stem from dysregulated decision-making processes, where uncertainty plays a central role. Dysfunctions in dopaminergic and noradrenergic pathways appear to disrupt the brain's representation of uncertainty, thereby altering exploratory behavior. In sum, the varying patterns of exploration-exploitation balance across different disorders are critical for understanding the challenges in learning and decision-making associated with neuropsychiatric conditions.