Thalamocortical Dysrhythmia
Thalamocortical dysrhythmia (TCD) is a proposed explanation for certain cognitive disorders. It occurs upon the disruption of normal gamma-band electrical activity between the cortex and thalamic neurons during awakened, conscious states. This disorder is associated with diseases and conditions such as neuropathic pain, tinnitus, and Parkinson’s disease and is characterized by the presence of unusually low-frequency resonance in the thalamocortical system. TCD is associated with disruption of many brain functions including cognition, sensory perception, and motor control and occurs when thalamocortical neurons become inappropriately hyperpolarized, allowing T-type calcium channels to activate and the oscillatory properties of the thalamocortical neurons to change. A repeated burst of action potentials occurs at lower frequencies in the 4–10 Hz range. These bursts can be sustained by inhibition from the thalamic reticular nucleus and may cause an activation of cortical regions that are normally inhibited by gamma-band activity during resonance column formation. While the effect of the deviation from normal patterns of gamma oscillatory activity during conscious perception is not entirely settled, it is proposed that the phenomenon can be used to explain chronic pain in cases where there is no specific peripheral nerve damage.
Read more about this topic: Recurrent Thalamo-cortical Resonance