The subcortical auditory nuclei contain not only neurons tuned to a specific frequency, but also those tuned to multiple parameters characterizing a sound. All these neurons are potentially subject to modulation by descending fibers from the auditory cortex (corticofugal modulation). In the past, we electrically stimulated cortical durationtuned neurons of the big brown bat, Eptesicus fuscus, a...

Activation of the cholinergic neurons in the basal forebrain (BF) desynchronizes cortical activity and enhances sensory processing during arousal and attention. How the cholinergic input modulates the activity of different subtypes of cortical neurons remains unclear. Using in vivo two-photon calcium imaging of neurons in layers 1 and 2/3 of mouse visual cortex, we show that electrical stimulat...

We have previously shown that fetal cortical transplants placed in lesion cavities in rat frontal cortex ameliorate the thalamic atrophy that occurs ipsilateral to such lesions. Moreover, the axotomized host brain thalamic neurons appear to sprout many fibers into the fetal cortical transplants. Lastly, cultured cortical and cerebellar neurons, but not glia, promote the survival of cultured tha...

Three-dimensional reconstructions of the normal rat embryonic (E) neocortex on days E15, E17, E19, and E21, using Skandha (software designed by J. Prothero, University of Washington, Seattle), show that the neocortical ventricular zone shrinks rapidly in the medial direction during cortical morphogenesis. [3H]thymidine autoradiography indicates that the shrinkage of the ventricular zone occurs ...

Cholinergic neurons in the rostral brainstem, including the pedunculopontine nucleus (PPN), are critical for switching behavioural state from sleep to wakefulness, and their presumed inactivity during sleep is thought to promote slow cortical rhythms that are characteristic of this state. However, it is possible that the diminished activity of cholinergic brainstem neurons during slow-wave slee...

The striatum receives massive cortical excitatory inputs and is densely innervated by dopamine. Striatal projection neurons form either the direct or indirect pathways. Models of Parkinson's disease propose that dopaminergic degeneration imbalances both pathways, although direct electrophysiological evidence is lacking. Here, striatal neurons were identified by electrophysiological criteria and...

Neocortical projection neurons, which segregate into six cortical layers according to their birthdate, have diverse morphologies, axonal projections and molecular profiles, yet they share a common cortical regional identity and glutamatergic neurotransmission phenotype. Here we demonstrate that distinct genetic programs operate at different stages of corticogenesis to specify the properties sha...

Laminar organization, a fundamental neural architecture in the CNS, is a prominent feature of the neocortex, where the cortical neurons in spatially distinct layers are generated from the common progenitors in a temporally distinct manner during development. Despite many advances in the characterization of the molecular mechanisms of the radial migration of cortical neurons, the way in which th...

GABAergic inhibition synchronizes oscillatory activity in the thalamocortical system. To understand better the role of this neurotransmitter in generation of thalamocortical rhythmicity, the postnatal development of GABAergic function mediated through activation of GABAA receptors was studied in thalamus and cortex. GABA-evoked chloride currents were recorded in dissociated rat cortical and tha...

The study of human cortical development has major implications for brain evolution and diseases but has remained elusive due to paucity of experimental models. Here we found that human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), cultured without added morphogens, recapitulate corticogenesis leading to the sequential generation of functional pyramidal neurons of all s...