Results 241 to 250 of about 186,183 (278)

Alpha Rhythm and Alpha-Like Activity in Coma

Clinical Electroencephalography, 1984
A normal waking EEG was obtained on a 22 year old man four days prior to cardiopulmonary arrest. Three days after resuscitation the EEG showed the pattern of alpha-like activity while the patient remained in deep coma. Since the EEGs were recorded by the same technician using the same 16 channel electroencephalograph and montages, it is possible to ...
P C, Fung, R P, Tucker
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Origin of the Alpha Rhythm

Nature, 1970
The 8–12 Hz rhythmical waveform that can be recorded from the scalp of most human subjects when their eyes are closed does not originate in brain tissue. It is generated by physiological tremor in the extra-ocular muscles modulating the field set up by the standing potential of the eye.
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Alpha rhythms: noise, dynamics and models

International Journal of Psychophysiology, 1997
Alpha rhythms appear as sinusoidal-like oscillations in the electroencephalogram (EEG) within the frequency range 8-12 Hz that waxe and wane in a more or less irregular way. The irregularity may have various origins. It may be due to noise or the oscillations may have an intrinsic irregular character, e.g.
Lopes da Silva, F.H., Pijn, J.P., Velis, D.N., Nijssen, P.C.G.   +3 more
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OCULOMOTOR ACTIVITY AND THE ALPHA RHYTHM

Perceptual and Motor Skills, 1990
From the beginning of clinical use of the EEG until now a close connection with oculomotor activity was assumed and empirically proven. After giving a sketch of the historical development, the issue is extended to the question of a connection between task-related alpha asymmetries and oculomotor activity.
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Perceptual framing and cortical alpha rhythm

Neuropsychologia, 1981
Abstract Apparent motion was used as a probe to test the hypothesis that perceptual framing is correlated to the phase of the alpha rhythm. Stimuli were presented phasically with respect to the occipital and parietal alpha cycle, and subjects were asked to judge whether the stimuli appeared simultaneous or sequential.
F J, Varela, A, Toro, E R, John, E L, Schwartz   +3 more
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Alpha rhythm and hypofrontality in schizophrenia

Acta Psychiatrica Scandinavica, 2008
Objective:  To reveal the EEG correlates of resting hypofrontality in schizophrenia (SZ).Method:  We analyzed the whole‐head EEG topography in 14 patients compared to 14 matched controls by applying a new parameterization of the multichannel EEG. We used a combination of power measures tuned for regional surface mapping with power measures that allow ...
M G, Knyazeva, M, Jalili, R, Meuli, M, Hasler, O, De Feo, K Q, Do   +5 more
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REM Alpha Rhythm: Diagnostic for Narcolepsy?

Journal of Clinical Neurophysiology, 2006
A young man, in whom narcolepsy was subsequently diagnosed, had the simultaneous onset of quadriparesis and a rapid eye movement (REM)-sleep polysomnographic pattern. During this REM-sleep pattern, a waking alpha EEG rhythm, appearing when he was asked to close his eyes, immediately attenuated when he was instructed to open his eyes, after which the ...
Mark Eric, Dyken, Evan J, Wenger, Thoru, Yamada   +2 more
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Alpha rhythm from eyes

Nature, 1974
The Origin of the Alpha Rhythm. By O. Lippold. Pp. ix + 267. (Churchill Livingstone: London and Edinburgh, 1973.) £6.
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Bilateral Separation in Alpha Rhythm Recording

Nature, 1970
WHEN recorded at different locations on the scalp with the conventional systems of electrode placement1,2, the waves of alpha rhythm tend to show a fairly high degree of correlation in their phase. It would be useful to know whether this correlation represents a true neuronal synchronization or whether it results from the inability to record separately
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Alpha Rhythm and the Pineal Gland

International Journal of Neuroscience, 1992
Alpha rhythm is classically described as a bilateral posterior rhythm of substantially constant frequency in the range of 8-13 Hz which is enhanced by mental relaxation and blocked by attention. Since the full expression of alpha rhythm has been shown to occur coincident with puberty, it is possible that the establishment of alpha rhythm is subject to ...
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