Thalamic Mechanisms of EEG Alpha Rhythms and Their Pathological Implications

摘要: During relaxed wakefulness, the human brain exhibits pronounced rhythmic electrical activity in alpha frequency band (8-13 Hz). This consists of 3 main components: classic occipital rhythm, Rolandic mu and so-called third rhythm. In recent years, long-held belief that rhythms are strongly influenced by thalamus has been confirmed several animal models and, humans, is well supported numerous noninvasive imaging studies. Of specific importance emergence 2 key cellular thalamic mechanisms, which come together to generate locally synchronized activity. First, a novel form burst firing, termed high-threshold (HT) bursting, occurs specialized subset thalamocortical (TC) neurons, second, interconnection this via gap junctions (GJs). Because repetitive HT bursting TC neurons range 13 Hz, with precise increasing depolarization, same components underlie can also lead theta (2-7 Hz) when neuron population less depolarized. As such, scenario explain both deceleration takes place during early sleep chronic slowing characterizes host neurological psychiatric disorders.