9 results match your criteria: "PA (Herman); and the Drexel University College of Medicine[Affiliation]"

According to the efficient coding hypothesis, sensory neurons are adapted to provide maximal information about the environment, given some biophysical constraints. In early visual areas, stimulus-induced modulations of neural activity (or tunings) are predominantly single-peaked. However, periodic tuning, as exhibited by grid cells, has been linked to a significant increase in decoding performance.

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Quantifying neural and non-neural contributions to the joint resistance in spasticity is essential for a better evaluation of different intervention strategies such as botulinum toxin A (BoTN-A). However, direct measurement of muscle mechanical properties and spasticity-related parameters in humans is extremely challenging. The aim of this study was to use a previously developed musculoskeletal model and optimization scheme to evaluate the changes of neural and non-neural related properties of the spastic wrist flexors during passive wrist extension after BoTN-A injection.

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Nested oscillations, where the phase of the underlying slow rhythm modulates the power of faster oscillations, have recently attracted considerable research attention as the increased phase-coupling of cross-frequency oscillations has been shown to relate to memory processes. Here we investigate the hypothesis that reactivations of memory patterns, induced by either external stimuli or internal dynamics, are manifested as distributed cell assemblies oscillating at gamma-like frequencies with life-times on a theta scale. For this purpose, we study the spatiotemporal oscillatory dynamics of a previously developed meso-scale attractor network model as a correlate of its memory function.

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Neuregulin and dopamine modulation of hippocampal gamma oscillations is dependent on dopamine D4 receptors.

Proc Natl Acad Sci U S A

August 2012

Neuronal Oscillations Laboratory, KI-Alzheimer Disease Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institute, 14186 Stockholm, Sweden.

The neuregulin/ErbB signaling network is genetically associated with schizophrenia and modulates hippocampal γ oscillations--a type of neuronal network activity important for higher brain processes and altered in psychiatric disorders. Because neuregulin-1 (NRG-1) dramatically increases extracellular dopamine levels in the hippocampus, we investigated the relationship between NRG/ErbB and dopamine signaling in hippocampal γ oscillations. Using agonists for different D1- and D2-type dopamine receptors, we found that the D4 receptor (D4R) agonist PD168077, but not D1/D5 and D2/D3 agonists, increases γ oscillation power, and its effect is blocked by the highly specific D4R antagonist L-745,870.

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A very large number of GABAergic neurons are activated in the tuberal hypothalamus during paradoxical (REM) sleep hypersomnia.

PLoS One

July 2010

CNRS, UMR5167, Physiopathologie des réseaux neuronaux du cycle veille-sommeil, Université Claude Bernard-Lyon 1, Université de Lyon, Lyon, France.

We recently discovered, using Fos immunostaining, that the tuberal and mammillary hypothalamus contain a massive population of neurons specifically activated during paradoxical sleep (PS) hypersomnia. We further showed that some of the activated neurons of the tuberal hypothalamus express the melanin concentrating hormone (MCH) neuropeptide and that icv injection of MCH induces a strong increase in PS quantity. However, the chemical nature of the majority of the neurons activated during PS had not been characterized.

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A case of Warthin's tumor with an unusual sialographic appearance is reported. The extensive pooling of the contrast media within the tumor was probably the result of communication of the cystic spaces of the tumor with the ductal system of the parotid gland. This case stimulated a re-examination of the incidence of this tumor, with a study of 205 major salivary gland tumors from pathology reports in the files of Hartford Hospital which is affiliated with the University of Connecticut Health Center in Farmington, Connecticut.

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