Effect of Neuromodulation on the Brain Dynamical Repertoire

Brain dynamics go beyond simple bistable models of regional activation, encompassing multiple coexisting states and transitions. Neural activity is constrained to low-dimensional manifolds, where structured flow governs brain function. Neuromodulators such as dopamine, serotonin, and acetylcholine shape this landscape by modulating synaptic plasticity, neuronal excitability, and network connectivity. Here, we investigate how neuromodulation alters neural dynamics. Using a neural mass model incorporating dopamine, we show that increasing dopaminergic input expands the repertoire of dynamical patterns and shifts their frequency content. These findings underscore the critical role of neuromodulation in shaping brain states and highlight the importance of computational models that integrate these effects to better understand both healthy and pathological brain dynamics.