Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 3

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  SYNCHRONIZATION
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Cortical synchronization suggests neural principles of visual feature grouping

100%
Eckhorn R.
Acta Neurobiologiae Experimentalis
|
2000
|
vol. 60
|
issue 2
261-269
EN
Compositions of visual scenes are related here to neural signals in visual cortex and to cortical circuit models to understand neural mechanisms of perceptual feature grouping. Starting from the hypothesis that synchronization and decoupling of cortical gamma-activities (35-90 Hz) define the relations among visual objects, we concentrate on synchronization related to (1) static retinal stimulation during ocular fixation, and (2) transient stimulation by sudden shifts in object position. The synchronization hypothesis has been tested by analyzing signal correlations in visual cortex of monkeys with the following results: Static retinal stimuli induce loosely phase-coupled gamma-activities among neurons of an object's cortical representation. Patches of gamma-synchronization become decoupled across the representation of an object's contour, and therby can code figure-ground segregation. Transient stimuli evoke synchronized volleys of stimulus-locked activities that are typically non-rhythmic and include low frequency components in addition to those in the gamma-range. It is argued that stimulus-induced and stimulus-locked synchronizations may play different roles in perceptual feature grouping.
2

The effect of carbachol on the phase of free-running locomotor activity rhythm under constant darkness (DD) and constant light (LL) in mice

100%
Gaweda M.
Folia Biologica
|
1998
|
vol. 46
202-213
EN
Carbachol chronically and peripherally administered, depending on the circadian time, caused a phase shift in the free-running locomotor activity rhythm, resynchronized the rhythm, or had a masking effect of this rhythm in mice. In the discussion it is stressed that the drug affects the rhythmicity of this activity, probably by acting on the mechanism of suprachiasmatic nuclei.
3
Content available remote

Reduced degree of long-range phase synchrony in pathological human brain

75%
Bhattacharya J.
Acta Neurobiologiae Experimentalis
|
2001
|
vol. 61
|
issue 4
309-318
EN
In this paper multivariate spontaneous EEG signals from three broad groups of human subjects - control, seizure, and mania - were studied with the aim of investigating the possible effect of these pathologies on the degree of phase synchronization between cortical areas. The degree of phase synchrony was measured by two recently developed measures which are more suitable than classical indices like correlation or coherence when dealing with nonlinear and non-stationary signals like the EEG. Signals were reduced to seven frequency bands (delta, theta, alpha-1, alpha-2, beta-1, beta-2 and gamma) which were statistically compared between the normal and the other two groups. It was found that the degree of long-range synchrony was significantly reduced for both pathological groups as compared with the control group. No clear differences were found in the degrees of short-range synchrony.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.