Slow brain potentials in a visual-spatial memory task: topographic distribution and inter-laboratory consistency.
Slow brain electrical potentials (SPs) were investigated in a visual-spatialmemory task. Two issues were addressed: (1) the nature and topographic distribution of the potentials obtained under such conditions; and (2) the consistency of the SPs when recorded in six identically configured laboratories. Fifteen young male subjects were studied at each laboratory (total n = 90). The paradigm entailed presentations of paired-visual patterns (S1 and S2), to which subjects responded with a choice reaction time response indicating whether or not the two patterns matched. A biphasic contingent negative variation (CNV) was produced which consisted of an early symmetric component with bilateral foci at posterior temporal sites and a subsequent mid-parietal dominant wave later in the retention interval. Although the CNVs from all laboratories were similar in waveform and in topographic distribution, there were significant inter-laboratory differences in amplitude of the slow potential components. The topographic distributions of the components and the possible role of sampling effects are discussed.
Rohrbaugh
J W
JW
Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA.
Dunham
D N
DN
Stewart
P A
PA
Bauer
L O
LO
Kuperman
S
S
O'Connor
S J
SJ
Porjesz
B
B
Begleiter
H
H
D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology*