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Sharp Wave-ripple Complexes
Sharp waves and ripples (SPW-R), also called sharp wave ripples (SWR), are oscillatory patterns produced by extremely synchronized activity of neurons in the mammalian hippocampus and neighboring regions which occur spontaneously in idle waking states or during NREM sleep. They can be observed with a variety of electrophysiological methods such as Electrophysiology, field recordings or Electroencephalography, EEG. They are composed of large amplitude sharp waves in local field potential and produced by thousands of neurons firing together within a 30–100 ms window. Within this broad time window, Pyramidal cell, pyramidal cells fire only at specific times set by fast spiking GABAergic interneurons. The fast rhythm of inhibition (150-200 Hz) synchronizes the firing of active pyramidal cells, each of which only fires one or two Action potential, action potentials exactly between the inhibitory peaks, collectively generating the ripple pattern. SWRs have been extensively characterized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sharp Wave Ripple
Sharp or SHARP may refer to: Acronyms * SHARP (helmet ratings) (Safety Helmet Assessment and Rating Programme), a British motorcycle helmet safety rating scheme * Self Help Addiction Recovery Program, a charitable organisation founded in 1991 by Barbara Bach and Pattie Boyd * Sexual Harassment/Assault Response & Prevention, a US Army program dealing with sexual harassment * Skinheads Against Racial Prejudice, an anti-racist Trojan skinhead organization formed to combat White power skinheads * Society for the History of Authorship, Reading and Publishing * Stationary High Altitude Relay Platform, a 1980s beamed-power aircraft * Super High Altitude Research Project, a 1990s project to develop a high-velocity gun * SIGINT High Altitude Replenishment Program (SHARP) Companies * I. P. Sharp Associates, a former Canadian computer services company * Sharp Airlines, an Australian regional airline * Sharp Corporation, a Japanese electronics manufacturer ** Sharp Solar, a manufacturer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long-term Potentiation
In neuroscience, long-term potentiation (LTP) is a persistent strengthening of synapses based on recent patterns of activity. These are patterns of synaptic activity that produce a long-lasting increase in signal transmission between two neurons. The opposite of LTP is long-term depression, which produces a long-lasting decrease in synaptic strength. It is one of several phenomena underlying synaptic plasticity, the ability of chemical synapses to change their strength. As memories are thought to be encoded by modification of synaptic strength, LTP is widely considered one of the major cellular mechanisms that underlies learning and memory. LTP was discovered in the rabbit hippocampus by Terje Lømo in 1966 and has remained a popular subject of research since. Many modern LTP studies seek to better understand its basic biology, while others aim to draw a causal link between LTP and behavioral learning. Still, others try to develop methods, pharmacologic or otherwise, of enhanci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Spindles
Sleep spindles are bursts of neural oscillatory activity that are generated by interplay of the thalamic reticular nucleus (TRN) and other thalamic nuclei during stage 2 NREM sleep in a frequency range of ~11 to 16 Hz (usually 12–14 Hz) with a duration of 0.5 seconds or greater (usually 0.5–1.5 seconds). After generation as an interaction of the TRN neurons and thalamocortical cells, spindles are sustained and relayed to the cortex by thalamo-thalamic and thalamo-cortical feedback loops regulated by both GABAergic and NMDA-receptor mediated glutamatergic neurotransmission. Sleep spindles have been reported (at face value) for all tested mammalian species. Considering animals in which sleep-spindles were studied extensively (and thus excluding results mislead by pseudo-spindlesGottesmann, C. (1996). The transition from slow-wave sleep to paradoxical sleep: evolving facts and concepts of the neurophysiological processes underlying the intermediate stage of sleep. Neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neocortex
The neocortex, also called the neopallium, isocortex, or the six-layered cortex, is a set of layers of the mammalian cerebral cortex involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands, spatial reasoning, and language. The neocortex is further subdivided into the true isocortex and the proisocortex. In the human brain, the cerebral cortex consists of the larger neocortex and the smaller allocortex, respectively taking up 90% and 10%. The neocortex is made up of six layers, labelled from the outermost inwards, I to VI. Etymology The term is from ''cortex'', Latin, " bark" or "rind", combined with ''neo-'', Greek, "new". ''Neopallium'' is a similar hybrid, from Latin ''pallium'', "cloak". ''Isocortex'' and ''allocortex'' are hybrids with Greek ''isos'', "same", and ''allos'', "other". Anatomy The neocortex is the most developed in its organisation and number of layers, of the cerebral tissues. The neocortex cons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stage2sleep
Stage, stages, or staging may refer to: Arts and media Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly British theatre newspaper * Stages Repertory Theatre, a theatre company in Houston, Texas Music Performers * Stage, an American band featuring Ryan Star Albums * ''Stage'' (David Bowie album), 1978 * ''Stage'' (Great White album), 1995 * ''Stage'' (Keller Williams album), 2004 * ''Stage'', by Mónica Naranjo, 2009 * ''The Stage'' (album), by Avenged Sevenfold, or the title song (see below), 2016 * ''Stages'' (Cassadee Pope album), 2019 * ''Stages'' (Elaine Paige album), 1983 * ''Stages'' (Eric Clapton album), 1993 * ''Stages'' (Jimi Hendrix album), 1991 * ''Stages'' (Josh Groban album), 2015 * ''Stages'' (Melanie C album), 2012 * ''Stages'' (Triumph album), 1985 * ''Stages'' (Vedera album), 2009 * '' Stages: The Lost Album'', b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Frequency Oscillations
High-frequency oscillations (HFO) are brain waves of the frequency faster than ~80 Hz, generated by neuronal cell population. High-frequency oscillations can be recorded during an electroencephalagram (EEG), local field potential (LFP) or electrocorticogram (ECoG) electrophysiology recordings. They are present in physiological state during sharp waves and ripples - oscillatory patterns involved in memory consolidation processes. HFOs are associated with pathophysiology of the brain like epileptic seizure and are often recorded during seizure onset. It makes a promising biomarker for the identification of the epileptogenic zone. Other studies points to the HFO role in psychiatric disorders and possible implications to psychotic episodes in schizophrenia. Background and history Traditional classification of the frequency bands, that are associated to different functions/states of the brain and consist of delta, theta, alpha, beta and gamma bands. Due to the limited capabiliti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
