Effects of neuromuscular training on physical and tennis-specific performance in youth and young adult male tennis players: A systematic review and meta-analysis.

Parkinson’s disease (PD) involves degeneration of the dopaminergic system, which is central not only for motor control but also for learning, decision-making, and exploratory behavior (–). The dopamine deficit in PD impairs several aspects of cognitive function, including the ability to learn from feedback and adapt to changes in reward contingencies (–). While simpler associative learning mechanisms can be preserved, patients show marked deficits in tasks that require building and using an internal model of the environment (). Dopaminergic medication in the form of levodopa can alleviate these impairments to some degree, especially when learning from reward feedback (, –). Critically, PD also interferes with the ability to navigate the exploration-exploitation trade-off (–), which requires balancing exploring promising novel options and exploiting known high-reward options. Whether deciding between ordering your favorite dish or trying something new, or choosing a new travel destination over a familiar favorite, the fundamental challenge is to choose between what is known to work and discovering something even better (–). Investigating how PD influences the exploration-exploitation trade-off is therefore important from both a clinical and theoretical perspective, as it links dopaminergic dysfunction to central mechanisms of learning and decision-making. An essential paradigm for investigating explore-exploit problems are bandit tasks, in which participants learn about choice options with uncertain outcomes through trial and error (–). In each trial, learners must choose between the available options, balancing the exploration of new options with the exploitation of known options. While many tasks in the literature have independent options where the outcome of one decision does not provide information about other options (–), natural environments are often characterized by structural regularities (–). For instance, spatially proximate areas often yield similar foraging outcomes (), and if two dishes share similar ingredients, trying one helps predict the taste of the other (). Such latent regularities can be used to generalize beyond direct experiences and adapt exploratory decisions to environmental structure ().