CRANDALL LAB at MSU
Dynamic properties of corticothalamic circuits
Virtually all sensory information enters the neocortex by way of the thalamus. The neocortex in turn sends a massive projection back to the thalamus. This curious organization suggests that the cortex must have a strong influence on thalamic activities and, thereby, its own sensory input. However, the impact of the corticothalamic pathway on thalamic processing has been a matter of discussion, due to the complexity of the circuits involved. In our lab, we use an array of electrophysiological techniques together with cell-type-specific optogenetic strategies to study the cellular connectivity and dynamic signaling in these circuits. These experiments will allow us to dissect corticothalamic circuits, and elucidate how cortical activity can control the spatial and temporal structure of incoming sensory signals.
Oh et al., Nature 2014
Top-down influences on somatosensory processing
A prominent but often neglected feature of sensory cortex is the presence of numerous feedback projections from higher-order cortical regions. Indeed, accumulating evidence has suggested top-down feedback may mediate cognitive processes such as attention, prediction, expectation, and awareness. However, the neural mechanisms by which feedback projections exert their influence on local cortical circuit functions is largely unknown. In our lab, we use the mouse somatosensory cortex as a model system to understand the dynamic interaction between sensory and motor cortices, with the goal of understanding the general principles of top-down influences.
Tuberous sclerosis complex
Tuberous sclerosis complex (TSC) is a rare genetic disorder caused by mutations in either the TSC1 or TSC2 genes, resulting in an overactive mechanistic target of rapamycin complex 1 (mTORC1) and benign tumor growth in the brain and other organs. Neurological involvement is common and often debilitating, with some TSC patients experiencing seizures, sleep disturbances, intellectual disability, and autism. However, the molecular, cellular, and neural circuit abnormalities underlying the neurobehavioral problems in TSC are not well understood. By applying cutting-edge electrophysiological techniques to mouse models of TSC, our lab is investigating the neurological manifestations of this rare genetic disorder. The knowledge obtained from our experiments may lead to new avenues of treatment, prevention methods, and, perhaps, a cure.
Our model system
We address our research goals using the mouse vibrissal (whisker) sensorimotor system, a leading model for the study of forebrain circuits and active sensation.