Frequency-specific analysis of gamma oscillationsстатьяТезисы
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 27 мая 2015 г.
Аннотация:The evoked gamma oscillations under perception of auditory stimuli were studied during passive and active attention. The frequency filtering of averaged evoked potentials with 1 Hz step in the range between 30 and 75 Hz was used. The method of three-dimensial dipole tracing (localization of equivalent dipole) was combined with structural MRI to identify localizations of gamma generators into the time window 0 –100 ms.
Frequency-specific gamma generators shapely tuned at different frequencies were revealed. These generators were excited independent.
In the conditions of passive attention equivalent dipoles of gamma generators were found mainly in auditory cortex. During active attention the same stimuli (performance of sensory-motor reaction) evoked dipole sources in prefrontal and/or cingular areas as well as in the auditory cortex. Under passive and active attention the frequency of oscillations in the part of gamma generators were identical .
Under active attention dipoles of gamma generators appeared at the beginning of 100 ms interval in prefrontal and/ or cingular cortexes and letter they were moved into auditory cortex and returned back to the prefrontal or cingular areas. This cycle is repeated four times during 100 ms after stimulus presentation.
It is assumed that under active attention gamma generators with fine frequency tuning contribute to auditory, prefrontal and cingular cortexes binding.
Key words: attention, gamma oscillations, dipole, binding