General anesthesia and the neural correlates of consciousness.

摘要: The neural correlates of consciousness must be identified, but how? Anesthetics can used as tools to dissect the nervous system. not only allow for experimental investigation into conscious-unconscious state transition, they also titrated subanesthetic doses in order affect selected components such memory, attention, pain processing, or emotion. A number basic neuroimaging examinations various anesthetic agents have now been completed. common pattern regional activity suppression is emerging which thalamus identified a key target effects on consciousness. It has proposed that neuronal hyperpolarization block at level thalamus, thalamocortical and corticocortical reverberant loops, could contribute anesthetic-induced unconsciousness. However, all anesthetics do suppress global cerebral metabolism cause regionally specific effect thalamic activity. Ketamine, so-called dissociative agent, increases humans associated with loss Nevertheless, it those few metabolic might still their mediated interactions, if scramble signals normal network Functional effective connectivity are analysis techniques investigate signal scrambling interactions. Whereas interactions yet investigated ketamine, disconnection during unconsciousness found both suppressive patients who persistent vegetative state. Furthermore, recovery from reconnection functional connectivity. Taken together these intriguing observations offer strong empirical support loop heart neurobiology