Intraoperative neurophysiological monitoring during endoscopic, endonasal approaches to the skull base is both feasible and safe. Numerous reports have recently emerged from the literature evaluating the efficacy of different neuromonitoring tests during endonasal procedures, making them relatively well-studied. The authors report on a comprehensive, multimodality approach to monitoring the fun...

Thalamocortical circuits are central to sensory and cognitive processing. Recent work suggests that the thalamocortical inputs onto L4 and L6, the main input layers of neocortex, are activated differently by visual stimulation. Whether these differences depend on layer-specific organization of thalamocortical circuits; or on specific properties of synapses onto receiving neurons is unknown. Her...

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...

This study was designed to examine possible anatomical changes of thalamocortical circuits in schizophrenics. Previous immunocytochemical studies have shown that parvalbumin, a calcium-binding protein, occurs in thalamocortical projection neurons, but not in GABAergic interneurons in the anteroventral thalamic nucleus (AN). Using parvalbumin-immunocytochemistry we investigated the densities of ...

Thalamocortical synapses may be able to undergo activity-dependent long-term changes in efficacy, such as long-term potentiation. Indeed, studies conducted in vivo have found that theta-burst stimulation (TBS) of the thalamus induces a long-term enhancement (LTE) of field potential responses evoked in the neocortex of adult rodents. Because the thalamus and neocortex form a complex interconnect...

Sensory stimuli reach the brain via the thalamocortical projection, a group of axons thought to be among the most powerful in the neocortex. Surprisingly, these axons account for only approximately 15% of synapses onto cortical neurons. The thalamocortical pathway might thus achieve its effectiveness via high-efficacy thalamocortical synapses or via amplification within cortical layer 4. In rat...

'Fast-spike' interneurons of layer 4 mediate thalamocortical feedforward inhibition and can, with some confidence, be identified using extracellular methods. In somatosensory barrel cortex of awake rabbits, these 'suspected inhibitory interneurons' (SINs) have distinct receptive field properties: they respond to vibrissa displacement with very high sensitivity and temporal fidelity. However, th...

BACKGROUND AND PURPOSE Thalamocortical connections play a crucial role in complex cognitive functioning, and several neuropsychiatric disorders may involve aberrant thalamocortical circuitry. Here, we quantified the cortical pattern and age-related changes of thalamocortical connections by using probabilistic tractography in children and adolescents. We hypothesized that detectable asymmetry (l...