A Neural Hybrid-System Model of the Basal Ganglia
Makin, Joseph Gerard
Technical Report Identifier: EECS-2007-16
January 16, 2007
Abstract: The basal ganglia are a set of functionally related and structurally interconnected nuclei in the human brain which form part of a closed loop between cortex and thalamus, receiving input from the former and outputting to the latter. The BG have been implicated in motor control and cognitive switching tasks; in particular, it is believed that the BG function as a controller for motor tasks by selectively disinhibiting appropriate portions of the thalamus and hence activating, via a feedback loop, cortical regions. These switching behaviors are perforce discrete, whereas the underlying dynamics of neuron voltages and neurotransmitter levels are continuous-time, continuous-state phenomena. To this end, we propose and simulate a hybrid automaton for modeling individual neurons that affords explicit representation of voltage discharges and discrete outputs along with continuous voltage dynamics within a single, elegant model; and which is amenable both to the construction of large networks -- in particular the cortico-basalthalamic loops -- and to analysis on such networks.