Gamma-band responses in the brain: a short review of psychophysiological correlates and functional significance.
The present study shows that gamma-band (40 Hz) activities exist in a number of brain structures of different species, with seemingly different functional/behavioral correlates. This rhythm has also different dynamics in various structures and under different experimental conditions: it exists spontaneously and/or can be evoked, induced or emitted with different latencies and relations to sensory-cognitive events. Recent measurements of gamma-band activity at the cellular level stress high level functional correlates such as binding of features. In contrast, field potential measurements in both humans and animals demonstrate that gamma-band responses may have multifold functions both in 'obligatory' sensory and in cognitive processing. With respect to the generators of gamma activity, experimental data hint at the existence of a distributed gamma system in the brain. Furthermore, an interpretation of gamma rhythms as universal functional building blocks is suggested.
Başar-Eroglu
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C
Institute of Psychology and Cognition Research, University of Bremen, Germany. cbasar@psycho2.psychologie.uni-bremen.de
Strüber
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D
Schürmann
M
M
Stadler
M
M
Başar
E
E
D000818:Animals; D001921:Brain / Q000502:physiology*; D002415:Cats; D003071:Cognition / Q000502:physiology*; D004569:Electroencephalography / Q000706:statistics & numerical data; D005071:Evoked Potentials / Q000502:physiology; D005556:Form Perception / Q000502:physiology*; D017952:Ganglia, Invertebrate / Q000502:physiology; D006801:Humans; D011817:Rabbits; D012908:Snails / Q000502:physiology