Linked Life Data

15488404

Source:http://linkedlifedata.com/resource/pubmed/id/15488404

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-10-18
pubmed:abstractText
Electroencephalography studies have suggested that the perception of illusory figures is associated with increases in gamma-band activity putatively reflecting the formation of synchronously firing neuronal assemblies. Here we assessed magnetoencephalographic gamma-band activity, which has been shown to be topographically more focal than in electroencephalogram. In line with functional brain imaging findings, we hypothesized gamma-band activity over ventral visual stream areas. In addition, we expected that the analysis of oscillatory activity would provide information on the time courses and connectivity patterns of these activations. Following a paradigm previously assessed with electroencephalography, 16 adults were presented four types of stimuli at equal probabilities: illusory (Kanizsa) triangles, real triangles, no-triangle stimuli with rotated inducer disks, and curved illusory triangles serving as targets that subjects had to respond to. Induced oscillatory responses were compared between illusory triangles and no-triangle stimuli and between illusory and real triangles using a statistical probability mapping method. Illusory triangles were distinguished from no-triangles by increased activity at around 70 Hz over midline occipital cortex peaking at 240 ms after stimulus onset. This was followed by activations over bilateral lateral occipital areas at 430 ms. Illusory triangles differed from real triangles by increased spectral activity at 90 Hz over posterior parietal cortex between 100 and 450 ms after stimulus onset, suggesting an involvement of visual dorsal stream regions. Coherence analysis showed increased connectivity between posterior parietal and lateral occipital cortex. These findings suggest that illusory triangles are encoded in parallel by networks along the visual ventral and dorsal streams.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1053-8119
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
551-60
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Magnetoencephalographic gamma-band responses to illusory triangles in humans.
pubmed:affiliation
MEG Center, Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstr. 29, 72076 Tübingen, Germany. jochen.kaiser@uni-tuebingen.de
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, Non-U.S. Gov't