Prestimulus Oscillatory Activity in the Alpha Band Predicts Visual Discrimination Ability

• DOI: 10.1523/jneurosci.1853-07.2008
• Publication Date: 2008-02-21T18:49:12Z
• Authors: Hanneke van Dijk; Jan-Mathijs Schof...; Robert Oostenveld; Ole Jensen
• Keywords: Vigilance (psychology); Alpha (finance); Magnetoencephalography; Sulcus; Occipital lobe; Visual N1

Although the resting and baseline states of human electroencephalogram magnetoencephalogram (MEG) are dominated by oscillations in alpha band (∼10 Hz), functional role these remains unclear. In this study we used MEG to investigate how spontaneous humans presented before visual stimuli modulate perception. Subjects had report if there was a subtle difference gray levels between two superimposed discs. We then compared prestimulus brain activity for correctly (hits) versus incorrectly (misses) identified stimuli. found that discrimination ability decreased with an increase power. Given reaction times did not vary systematically power changes vigilance likely explain change ability. Source reconstruction using spatial filters allowed us identify areas accounting effect. The dominant sources modulating perception were localized around parieto-occipital sulcus. suggest reflects inhibition imposed higher level areas, which serves gain stream.