Thalamus as the control center for information flow in the CNS

다국어 초록 (Multilingual Abstract)

The thalamus is actively engaged in shaping and modulating the afferent signals from the periphery to relay to the cortex. The intrinsic properties of thalamocortical relay(TC) neurons play an important role in this 'sensory gating' process. For example, burst spike activities of TC neurons that are driven by low threshold Ca^(2+) currents mediated by α1G T-type channels appear to set the 'closed gate' state. Thus, mice lacking the thalamic burst firing due to a deletion of the α1G T-type channel show hyperalgesic responses to persistent pain, accompanied by an increase in pain-encoding tonic spikes in TC neurons. Furthermore, the mutant mice show sleep disturbances and resistance to the development of absence seizures. These phenotypes are all related to an impairment of the mutant mice in the sensory gating function of the thalamus. In addition to this role in the upward signaling process, the thalamus is also involved in other brain functions.
An important question is how the thalamocortical circuit is regulated to control the intrinsic property of TC neurons and how this property controls the information flow in the brain. We addressed this question by analyzing several mutant mouse lines that show phenotypes indicative of an altered thalamic function.
In this talk, I will briefly review the roles of the thalamocortical circuit and discuss new findings, including the thalamic function in memory modulation.