In primary sensory and motor cortex of adult animals, alteration of input from the periphery leads to changes in cortical topography. These changes can be attributed to processes that are intrinsic to the cortex, or can be inherited from alterations occurring at stages of sensory processing that are antecedent to the primary sensory cortical areas. In the visual system, focal binocular retinal ...

Thalamocortical afferents innervate both excitatory and inhibitory cells, the latter in turn producing disynaptic feedforward inhibition, thus creating fast excitation-inhibition sequences in the cortical cells. Since this inhibition is disynaptic, the time lag of the excitation-inhibition sequence could be approximately 2-3 ms, while it is often as short as only slightly above 1 ms; the mechan...

Neurons may serve different functions over the course of an organism's life. Recent evidence suggests that cortical subplate (SP) neurons including those that reside in the white matter may perform longitudinal multi-tasking at different stages of development. These cells play a key role in early cortical development in coordinating thalamocortical reciprocal innervation. At later stages of dev...

The reticular nucleus (RT) of the thalamus, a thin sheet of GABAergic neurons located between the external medullary lamina and the internal capsule of the thalamus, has functionally distinct afferent and efferent connections with thalamic nuclei, the neocortex, the basal forebrain and the brainstem. RT is critically positioned to rhythmically pace thalamocortical networks leading to the genera...

The thalamic reticular nucleus (TRN) consists of GABA-containing neurons that form reciprocal synaptic connections with thalamic relay nuclei. Excitatory synaptic innervation of TRN neurons arises from glutamatergic afferents from thalamocortical relay neurons and deep layer corticothalamic neurons, and they produce excitation via both N-methyl-D-aspartate (NMDA) and non-NMDA receptors. Quinoxa...

UNLABELLED Thalamocortical neurons have thousands of synaptic connections from layer VI corticothalamic neurons distributed across their dendritic trees. Although corticothalamic synapses provide significant excitatory input, it remains unknown how different spatial and temporal input patterns are integrated by thalamocortical neurons. Using dendritic recording, 2-photon glutamate uncaging, and...

Flavoprotein autofluorescence imaging was used to examine auditory cortical synaptic responses in aged animals with behavioral evidence of tinnitus and hearing loss. Mice were exposed to noise trauma at 1-3 months of age and were assessed for behavioral evidence of tinnitus and hearing loss immediately after the noise trauma and again at ~24-30 months of age. Within 2 months of the final behavi...

Anterograde tracers, Phaseolus vulgaris leucoagglutinin (PHA-L) and horseradish peroxidase (HRP), were used to study the thalamocortical afferents of the posteromedial barrel subfield (PMBSF) in rat primary somatosensory cortex (SI) at both light- and electron-microscopic levels. The PMBSF, also known as the barrel cortex, can be subdivided into barrel and interbarrel areas on the basis of cyto...

We studied thalamocortical afferent (TCA) growth into somatosensory cortex as the whisker barrels emerge in postnatal mice. Ingrowing fibers from the ventrobasal (VB) thalamus were selectively labeled by two means. Under direct vision, individual axons and populations of axons were labeled in vitro with HRP, or in fixed tissue with Dil (1,1'-dioctodecyl-3,3,3',3'-tetramethylindocarbocyanine per...