Physiologically, the thalamocortical system is a central neural circuit that connects the thalamus to the cerebral cortex and is essential for processing and relaying sensory and motor information during wakefulness. This function is central for conscious behavior. During sleep the thalamus acts as generator of slow rhythms seen as spindles and delta waves in the EEG. Disruption of thalamocortical interaction and altered cellular properties of the involved neurons leads to number of neurological and neuropsychiatric conditions. 
 

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