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THE SYNAPSE
THE SYNAPSE

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Physiological origins and functional correlates of EEG rhythmic
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... Recent neurophysiological evidence, however, suggests an alternative explanation for these frequency changes. Both Steriade, Dossi, and Nunez (1991) and McCormick and Huguenard (1992) found that the frequency of membrane potential oscillations in thalamic relay cells slows when hyperpolarization is ...
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MS Word Version
MS Word Version

... 37. (Page 12.) Glutamate is the most common and most potent excitatory neurotransmitter in the central nervous system. Glutamate acts directly on ion channels that permit passage of both _______ and _______, producing fast excitatory postsynaptic potentials. a. sodium, potassium b. chloride 38. (Pag ...
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Abstract Browser  - The Journal of Neuroscience
Abstract Browser - The Journal of Neuroscience

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actively spiking compared with non-spiking human epileptic
actively spiking compared with non-spiking human epileptic

... permit EEG localisation. However, the possibility that these drugs even in low dosage may have influenced the amino acid and enzyme values cannot be excluded. None had received valproate which the acute administration of high doses in experimental animal studies is reported to result in a reduction ...
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Mapping form and function in the human brain: the emerging field of

... Division of Neurogenetics, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA Howard Hughes Medical Institute, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical Center, Boston, MA, USA Received 2 June 2003; revised 12 S ...
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Spike-and-wave



Spike-and-wave is the term that describes a particular pattern of the electroencephalogram (EEG) typically observed during epileptic seizures. A spike-and-wave discharge is a regular, symmetrical, generalized EEG pattern seen particularly during absence epilepsy, also known as ‘petit mal’ epilepsy. The basic mechanisms underlying these patterns are complex and involve part of the cerebral cortex, the thalamocortical network, and intrinsic neuronal mechanisms. The first spike-and-wave pattern was recorded in the early twentieth century by Hans Berger. Many aspects of the pattern are still being researched and discovered, and still many aspects are uncertain. The spike-and-wave pattern is most commonly researched in absence epilepsy, but is common in several epilepsies such as Lennox-Gastaut syndrome (LGS) and Ohtahara syndrome. Anti-epileptic drugs (AEDs) are commonly prescribed to treat epileptic seizures, and new ones are being discovered with less adverse effects. Today, most of the research is focused on the origin of the generalized bilateral spike-and-wave discharge. One proposal suggests that a thalamocortical (TC) loop is involved in the initiation spike-and-wave oscillations. Although there are several theories, the use of animal models has provided new insight on spike-and-wave discharge in humans.
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