Unravelling homeostatic interactions in inhibitory and excitatory networks in human motor cortex

摘要

Homeostatic plasticity has emerged as a fundamental regulatory principle that helps to stabilize neuronal and circuit activity within optimal ranges (Bienenstock et al. 1982; Abbott & Nelson, 2000). Using a priming-test approach, transcranial brain stimulation techniques have been successfully employed to study regional homeostatic metaplasticity in the intact human motor cortex (Ml) (Iyer et al. 2003; Lang et al. 2004; Siebner et al. 2004; Muller etal. 2007; Nitsche etal. 2007; Todd et al. 2009). In these studies, a priming stimulation protocol triggers a homeostatic response in Ml, which then is captured by a second test stimulation protocol. Usually, the motor evoked potential (MEP) elicited by single-pulse transcranial magnetic stimulation (TMS) is used as read-out to trace homeostatic metaplasticity.