Linked Life Data

17133886

Source:http://linkedlifedata.com/resource/pubmed/id/17133886

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2006-11-30
pubmed:abstractText
Masking is an important tool in many paradigms used to study the cognitive architecture. The N2pc is an electrophysiological event-related potential (ERP) that has been used as a tool to study the deployment of visual spatial attention. The aim of this paper was to study the effects of masking on the N2pc. Two stimuli were presented on the screen, one to left and one to right of fixation, and subjects reported the identity of one of them. The targets could be discriminated both by their category (letters vs. digit) and by their colour (pink vs. green). Backward masking was produced by presenting a second pair of bilateral stimuli after the offset of the first pair. The second pair of stimuli consisted of characters of the same colour and category as in the first pair. Forward masking was produced by using the very same stimuli as in the backward masking condition, but by instructing subjects to report the second stimulus. The forward mask trials had longer response times compared to no-mask trials, and backward mask trials had even longer response times, and also a higher error rate. Although the different masking procedures lead to clear behavioural effects, the N2pc was not affected, suggesting that the deployment of visual spatial attention, per se, was not affected by pattern masking. A sustained posterior contralateral negativity (SPCN) following the N2pc was also found (300 ms post-target, and beyond), and the amplitude of the SPCN was strongly modulated by the number of presented stimuli and the duration of the SPCN was positively correlated with RT in the behavioural task. We hypothesize that the SPCN reflects neural activity associated with the passage of information through visual short-term memory.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1196-1961
pubmed:author
pubmed:issnType
Print
pubmed:volume
60
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
101-11
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Fundamental properties of the N2pc as an index of spatial attention: effects of masking.
pubmed:affiliation
Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal.
pubmed:publicationType
Journal Article, Comparative Study