Document Detail


Determining working memory from ERP topography.
MedLine Citation:
PMID:  10582564     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Event-related potentials were recorded during a delayed matching-to-sample design from 17 volunteers (5 f) using high-resolution (65 channels) EEG-recordings. In the two-stimulus paradigm, the 500-ms stimulus S1 comprised a visual pattern of two diamonds differing in size, angular rotation and location; in the delay period, Working Memory (WM) load was varied in the following way: a stimulus-free interval of 1 s was followed by a 6-s presentation either of a pattern identical to the S1 (low WM load) or of a pattern differing from S1 (high WM load). The 500-ms stimulus S2 comprised one diamond; the subject's task was to indicate by left- or right-hand (respectively) button press, whether the S2 matched the (a) left- or (b) right-positioned S1-diamond, or (c) did not match at all (NoGo). The topographical distribution of activity in the time intervals (a) following S1-offset, (b) during the WM manipulation interval and (c) prior to S2 were evaluated in the signal (scalp potential) and source (Minimum Norm) space. Following S1-offset the ERP pattern was characterised by negativity over posterior areas, slightly more so over the right hemisphere. In the subsequent 6-s interval high WM load elicited a larger negative slow ERP than low WM load, the negativity increase due to high WM load being larger over frontal than central areas. Source modelling indicated activity in anterior areas under high, and posterior activity under low WM load. Asymmetry of activity, although indicating a shift to left-hemispheric activity under high compared to low WM load, varied considerably between subjects. Results suggest that high-resolution ERP recordings allow to examine cortical activity during WM challenge.
Authors:
A Löw; B Rockstroh; R Cohen; O Hauk; P Berg; W Maier
Related Documents :
15275844 - Load transfer mechanics between trans-tibial prosthetic socket and residual limb--dynam...
24051524 - Detection of upscale-crop and partial manipulation in surveillance video based on senso...
7802874 - Strain gauged six-component load transducer for use in upper limb biomechanics.
15676814 - Endurance limits in different modes of load holding.
15326114 - Characteristics of human corneal psychophysical channels.
19533674 - A photoelectrochemical method for determining the kinematics of moving particles using ...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Brain topography     Volume:  12     ISSN:  0896-0267     ISO Abbreviation:  Brain Topogr     Publication Date:  1999  
Date Detail:
Created Date:  1999-12-23     Completed Date:  1999-12-23     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  8903034     Medline TA:  Brain Topogr     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  39-47     Citation Subset:  IM    
Affiliation:
Department of Psychology, University of Konstanz, Germany.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adolescent
Adult
Brain Mapping
Cerebral Cortex / physiology*
Electroencephalography
Evoked Potentials / physiology*
Female
Humans
Male
Memory, Short-Term / physiology*
Neuropsychological Tests
Psychomotor Performance / physiology
Reaction Time / physiology
Task Performance and Analysis

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  P300 and response selection: a new look using independent-components analysis.
Next Document:  Dipole source analysis in persistent mirror movements.