Measurement and source estimation of MEG activities associated with a delayed-match paradigm

Author

NAKAGAWA, Seiji ; Ueno, Shoogo ; Yamanami, Kenji ; Iwaki, Satoshi ; Ueno, Kenichi ; Imada, Toshiaki

Author_Institution

Dept. of Biomed. Eng., Tokyo Univ., Japan

Volume

3

fYear

1997

fDate

30 Oct-2 Nov 1997

Firstpage

1244

Abstract

Visually evoked magnetoencephalograms (MEGs) associated with a delayed-match paradigm were measured to obtain functional information related to short-term memory processes. A delayed-match paradigm was introduced. The paradigm consists of a four-color-stimuli; a pair of circles with four differently-colored regions. The subjects retain the first image (Sample) until the second image (Test) appears. The MEGs were measured by a 122-channel whole-head-type SQUID system. A DC-like slow wave was observed at the period between latencies of 900 and 1500 msec during the short-term memory task. The source localization of the DC-like slow wave was estimated. The estimated sources were localized either in the occipital or postero-temporal region

Keywords

magnetoencephalography; medical signal processing; neurophysiology; parameter estimation; DC-like slow wave; MEG activities; delayed-match paradigm; differently-colored regions; four-color-stimuli; functional information; occipital region; pair of circles; postero-temporal region; short-term memory processes; source estimation; source localization; vertical EOG; visually evoked magnetoencephalograms; whole-head-type SQUID system; Biomedical measurements; Delay estimation; Eyes; Fingers; Humans; Magnetic field measurement; Magnetic shielding; Monitoring; SQUIDs; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Engineering in Medicine and Biology Society, 1997. Proceedings of the 19th Annual International Conference of the IEEE

Conference_Location

Chicago, IL

ISSN

1094-687X

Print_ISBN

0-7803-4262-3

Type

conf

DOI

10.1109/IEMBS.1997.756593

Filename

756593