Linked Life Data

17214572

Source:http://linkedlifedata.com/resource/pubmed/id/17214572

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-1-11
pubmed:abstractText
Working memory involves the short-term storage and manipulation of information necessary for cognitive performance, including comprehension, learning, reasoning and planning. Although electroencephalogram (EEG) rhythms are modulated during working memory, the temporal relationship of EEG oscillations with the eliciting event has not been well studied. In particular, the dynamics of the neural network supporting memory processes may be best captured in induced oscillations, characterized by a loose temporal link with the stimulus. In order to differentiate induced from evoked functional processes, the present study proposes a time-frequency analysis of the 3 to 30 Hz EEG oscillatory activity in a verbal n-back working memory paradigm. Control tasks were designed to identify oscillatory activity related to stimulus presentation (passive task) and focused attention to the stimulus (detection task). Evoked theta activity (4-8 Hz) phase-locked to the visual stimulus was evidenced in the parieto-occipital region for all tasks. In parallel, induced theta activity was recorded in the frontal region for detection and n-back memory tasks, but not for the passive task, suggesting its dependency on focused attention to the stimulus. Sustained induced oscillatory activity was identified in relation to working memory in the theta and beta (15-25 Hz) frequency bands, larger for the highest memory load. Its late occurrence limited to nonmatched items suggests that it could be related to item retention and active maintenance for further task requirements. Induced theta and beta activities displayed respectively a frontal and parietal topographical distribution, providing further functional information on the fronto-posterior network supporting working memory.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0898-929X
pubmed:author
pubmed:issnType
Print
pubmed:volume
19
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
158-72
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Distinction between perceptual and attentional processing in working memory tasks: a study of phase-locked and induced oscillatory brain dynamics.
pubmed:affiliation
University Hospitals of Geneva, Switzerland. P.DeiberIbanez@hcuge.ch
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't