Decoding Competition in the Brain

Competition is a key evolutionary force that drives organisms to exceptional performance in pursuit of critical goals, such as sex or food. Yet it can also induce excessive risk-taking and maladaptive behaviours. Despite its ubiquitous role in nature and human society, we still lack a mechanistic account of how the presence of rivals (‘competitive pressure’) is translated into changes in decision-making. This programme pioneers a multiscale dissection of how competitive pressure recalibrates motivational choice, using Drosophila for its unique genetic and neural-circuit tractability. We discovered that flies exposed to rivals persist in mating and feeding despite visual threats. This behaviour requires prior social experience, implicating long-lasting changes in neural circuits. We will investigate circuit signalling from molecules to networks to understand the underpinnings of competition-driven decision-making. We seek to (1) establish how competitive pressure affects the neural dynamics underlying high-risk decisions; (2) uncover the molecular and cellular-plasticity mechanisms by which competitive context induces long-term effects on decision-making; and (3) test whether common neuromodulatory networks (dopamine/serotonin/neuropeptides) and core neural principles bias decision-making across competitive contexts. This research will address whether competitive pressure functions as a ‘master motivation’, a high-level organiser of behavioural priorities that governs how animals arbitrate between conflicting drives.