Alpha waves: A neural signature of visual suppression
Authors: Toscani, M., Marzi, T., Righi, S., Viggiano, M.P. and Baldassi, S.
Journal: Experimental Brain Research
Volume: 207
Issue: 3-4
Pages: 213-219
ISSN: 0014-4819
DOI: 10.1007/s00221-010-2444-7
Abstract:Alpha waves are traditionally considered a passive consequence of the lack of stimulation of sensory areas. However, recent results have challenged this view by showing a modulation of alpha activity in cortical areas representing unattended information during active tasks. These data have led us to think that alpha waves would support a 'gating function' on sensorial stimulation that actively inhibits unattended information in attentional tasks. Visual suppression occurring during a saccade and blink entails an inhibition of incoming visual information, and it seems to occur at an early processing stage. In this study, we hypothesized that the neural mechanism through which the visual system exerts this inhibition is the active imposition of alpha oscillations in the occipital cortex, which in turn predicts an increment of alpha amplitude during a visual suppression phenomena. We measured visual suppression occurring during short closures of the eyelids, a situation well suited for EEG recordings and stimulated the retinae with an intra-oral light administered through the palate. In the behavioral experiment, detection thresholds were measured with eyes steady open and steady closed, showing a reduction of sensitivity in the latter case. In the EEG recordings performed under identical conditions we found stronger alpha activity with closed eyes. Since the stimulation does not depend on whether the eyes were open or closed, we reasoned that this should be a central effect, probably due to a functional role of alpha oscillation in agreement with the 'gating function' theory. © 2010 Springer-Verlag.
Source: Scopus
Alpha waves: a neural signature of visual suppression.
Authors: Toscani, M., Marzi, T., Righi, S., Viggiano, M.P. and Baldassi, S.
Journal: Exp Brain Res
Volume: 207
Issue: 3-4
Pages: 213-219
eISSN: 1432-1106
DOI: 10.1007/s00221-010-2444-7
Abstract:Alpha waves are traditionally considered a passive consequence of the lack of stimulation of sensory areas. However, recent results have challenged this view by showing a modulation of alpha activity in cortical areas representing unattended information during active tasks. These data have led us to think that alpha waves would support a 'gating function' on sensorial stimulation that actively inhibits unattended information in attentional tasks. Visual suppression occurring during a saccade and blink entails an inhibition of incoming visual information, and it seems to occur at an early processing stage. In this study, we hypothesized that the neural mechanism through which the visual system exerts this inhibition is the active imposition of alpha oscillations in the occipital cortex, which in turn predicts an increment of alpha amplitude during a visual suppression phenomena. We measured visual suppression occurring during short closures of the eyelids, a situation well suited for EEG recordings and stimulated the retinae with an intra-oral light administered through the palate. In the behavioral experiment, detection thresholds were measured with eyes steady open and steady closed, showing a reduction of sensitivity in the latter case. In the EEG recordings performed under identical conditions we found stronger alpha activity with closed eyes. Since the stimulation does not depend on whether the eyes were open or closed, we reasoned that this should be a central effect, probably due to a functional role of alpha oscillation in agreement with the 'gating function' theory.
Source: PubMed
Alpha waves: a neural signature of visual suppression
Authors: Toscani, M., Marzi, T., Righi, S., Viggiano, M.P. and Baldassi, S.
Journal: EXPERIMENTAL BRAIN RESEARCH
Volume: 207
Issue: 3-4
Pages: 213-219
ISSN: 0014-4819
DOI: 10.1007/s00221-010-2444-7
Source: Web of Science (Lite)
Alpha waves: a neural signature of visual suppression.
Authors: Toscani, M., Marzi, T., Righi, S., Viggiano, M.P. and Baldassi, S.
Journal: Experimental brain research
Volume: 207
Issue: 3-4
Pages: 213-219
eISSN: 1432-1106
ISSN: 0014-4819
DOI: 10.1007/s00221-010-2444-7
Abstract:Alpha waves are traditionally considered a passive consequence of the lack of stimulation of sensory areas. However, recent results have challenged this view by showing a modulation of alpha activity in cortical areas representing unattended information during active tasks. These data have led us to think that alpha waves would support a 'gating function' on sensorial stimulation that actively inhibits unattended information in attentional tasks. Visual suppression occurring during a saccade and blink entails an inhibition of incoming visual information, and it seems to occur at an early processing stage. In this study, we hypothesized that the neural mechanism through which the visual system exerts this inhibition is the active imposition of alpha oscillations in the occipital cortex, which in turn predicts an increment of alpha amplitude during a visual suppression phenomena. We measured visual suppression occurring during short closures of the eyelids, a situation well suited for EEG recordings and stimulated the retinae with an intra-oral light administered through the palate. In the behavioral experiment, detection thresholds were measured with eyes steady open and steady closed, showing a reduction of sensitivity in the latter case. In the EEG recordings performed under identical conditions we found stronger alpha activity with closed eyes. Since the stimulation does not depend on whether the eyes were open or closed, we reasoned that this should be a central effect, probably due to a functional role of alpha oscillation in agreement with the 'gating function' theory.
Source: Europe PubMed Central