Excitation/Inhibition Interactions and Seizures: the Brain’s Lifelong Balancing Act
We crave excitement;
Momma said too much is bad;
She favors GABA.
Excitation and Inhibition
The vertebrate central nervous system evolved in conjunction with sense organs and muscles to detect and localize food, and to coordinate the muscle contractions that allow individuals to pursue, apprehend, and consume it (Gans and Northcutt 1983; Grillner et al. 1998). Acetylcholine conveys the excitatory signal at neuromuscular synapses, while glutamate conveys the excitatory signal at most synapses of mature brains. However, “excitation” as a property resides not in the signaling substances themselves, but in the responses of postsynaptic cells to these substances. Responses to the same chemical signals (“neurotransmitters”) can vary significantly from one brain locale to another, and in the same locale under changing physiological conditions.
KeywordsGABAA Receptor Transmembrane Potential GABAergic Neuron Postsynaptic Neuron Excitatory Neuron
List of Abbreviations
Gamma-amino butyric acid
Supported by NINDS grants NS020253, NS048856, NS058303, a grant from PACE, and the Heffer Family Medical Foundation. SLM is the recipient of the Martin A. and Emily L. Fisher fellowship in Neurology and Pediatrics.
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