Linked Life Data

11346889

Source:http://linkedlifedata.com/resource/pubmed/id/11346889

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2001-5-10
pubmed:abstractText
The spatial and temporal characteristics of the brain processes underlying memory retrieval were studied with both event-related potentials (ERP) and positron emission tomography (PET) techniques. Subjects studied lists of 20 words and then performed episodic (old/new judgment) or semantic (living/nonliving decision) retrieval tasks on multiple four-item test lists, each lasting 10 sec. The PET and ERP measurements at test were assessed in relation to both the task (episodic vs. semantic) and the item (old vs. new or living vs. nonliving). Episodic retrieval was associated with increased blood flow in the right frontal lobe (Brodmann Area 10) and a sustained, slowly developing positive ERP shift recorded from the right frontopolar scalp. Semantic retrieval was associated with increased blood flow in the left frontal (Area 45) and temporal (Area 21) lobes but no clear ERP concomitant. The two retrieval tasks also differed from each other in the ERPs to single items in an early (300-500 ms) time window. Item-related comparisons yielded convergent results mainly if the retrieved information was relevant to the given task (e.g., old/new items during episodic retrieval and living/nonliving items during semantic retrieval). Episodically retrieved old items were associated with increased blood flow in the left medial temporal lobe and a transient increase in the amplitude of the late positive component (500-700 ms) of the ERP. Semantically retrieved living items were associated with increased blood flow in the left frontal cortex and anterior cingulate and a transient late frontal slow wave (700-1,500 ms) in the ERPs. These results indicate that the brain regions engaged in memory retrieval are active in either a sustained or transient manner. They map task-related processes to sustained and item-related processes to transient neural activity. But they also suggest that task-related factors can transiently affect early stages of item processing.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1065-9471
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
104-23
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Comparative electrophysiological and hemodynamic measures of neural activation during memory-retrieval.
pubmed:affiliation
Department of Neurology II, O.v.G. University of Magdeburg, Magdeburg, Germany. emrah.duezel@medizin.uni-magdeburg.de
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't