title: Neuromodulation of circuits with variable parameters: single neurons and small circuits reveal principles of state-dependent and robust neuromodulation.
abstract: Neuromodulation underlies many behavioral states and has been extensively studied in small circuits. This has allowed the systematic exploration of how neuromodulatory substances and the neurons that release them can influence circuit function. The physiological state of a network and its level of activity can have profound effects on how the modulators act, a phenomenon known as state dependence. We provide insights from experiments and computational work that show how state dependence can arise and the consequences it can have for cellular and circuit function. These observations pose a general unsolved question that is relevant to all nervous systems: How is robust modulation achieved in spite of animal-to-animal variability and degenerate, nonlinear mechanisms for the production of neuronal and network activity?
authors.affiliation: Volen Center and Biology Department, Brandeis University, Waltham, Massachusetts 02454; email: marder@brandeis.edu , toleary@brandeis.edu , sshruti@brandeis.edu.
authors.forename: Eve
authors.initials: E
authors.lastname: Marder
authors.forename: Timothy
authors.initials: T
authors.lastname: O'Leary
authors.forename: Sonal
authors.initials: S
authors.lastname: Shruti
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D063132:Connectome; D006706:Homeostasis / Q000502:physiology; D008959:Models, Neurological; D009434:Neural Pathways / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000502:physiology*; D013569:Synapses / Q000502:physiology*
chemical_list: D018377:Neurotransmitter Agents
keywords: biogenic amines; central pattern generators; intrinsic excitability; neuropeptides; stomatogastric nervous system; synaptic strength