PMID- 19159692
OWN - NLM
STAT- MEDLINE
DCOM- 20090513
LR  - 20090603
IS  - 1095-9572 (Electronic)
IS  - 1053-8119 (Linking)
VI  - 45
IP  - 2
DP  - 2009 Apr 1
TI  - The Visual Evoked Potential is independent of surface alpha rhythm phase.
PG  - 463-9
LID - 10.1016/j.neuroimage.2008.12.031 [doi]
AB  - A Visual Evoked Potential (VEP) is an electrical signal picked up by a surface 
      electrode in response to the activation of visual cortex by a visual stimulus. 
      Because the VEP is typically much smaller in magnitude than the ongoing 
      spontaneous EEG signal, the VEP is derived by averaging a large number of 
      responses time-locked to stimulus presentation. Standard theory has it that the 
      VEP is independent of the ongoing EEG, however, there has long been a competing 
      view that the VEP is caused by a partial phase reset of the spontaneous alpha 
      rhythm. We calculated the VEP where stimuli were presented at four different 
      phases of the ongoing alpha rhythm, and subtracted away the responses to null 
      trials synchronized to the same alpha rhythm phases, creating estimates of the 
      VEP as a function of ongoing alpha rhythm phase. For some subjects there was 
      evidence of an interaction between the VEP and the phase of the ongoing alpha 
      rhythm, but this was idiosyncratic between subjects and conditions, and mostly 
      evident in a later period when the VEP magnitude was very small. However, in 
      general the VEP is independent of the phase of the ongoing alpha rhythm, and 
      hence cannot be primarily caused by a partial phase resetting of the spontaneous 
      EEG. It is possible that the VEP is either a phase-reset of an ongoing 
      oscillation, or an oscillation induced by the sudden onset of a stimulus, but it 
      cannot be the same oscillation as the surface alpha.
FAU - Risner, Michael L
AU  - Risner ML
AD  - University of Alabama at Birmingham (UAB), Department of Vision Sciences, 924 
      South 18th St. Birmingham, AL 35294, USA.
FAU - Aura, Christopher J
AU  - Aura CJ
FAU - Black, James E
AU  - Black JE
FAU - Gawne, Timothy J
AU  - Gawne TJ
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20081230
PL  - United States
TA  - Neuroimage
JT  - NeuroImage
JID - 9215515
SB  - IM
CIN - Neuroimage. 2009 Aug 1;47(1):5-7. PMID: 19345739
CIN - Neuroimage. 2009 Aug 1;47(1):1-4. PMID: 19376248
MH  - Adult
MH  - Alpha Rhythm/*methods
MH  - Electroencephalography/*methods
MH  - Evoked Potentials, Visual/*physiology
MH  - Female
MH  - Humans
MH  - Male
MH  - Middle Aged
MH  - Reproducibility of Results
MH  - Sensitivity and Specificity
MH  - Statistics as Topic
MH  - Visual Cortex/*physiology
MH  - Young Adult
EDAT- 2009/01/23 09:00
MHDA- 2009/05/14 09:00
CRDT- 2009/01/23 09:00
PHST- 2008/07/21 00:00 [received]
PHST- 2008/12/05 00:00 [revised]
PHST- 2008/12/18 00:00 [accepted]
PHST- 2009/01/23 09:00 [entrez]
PHST- 2009/01/23 09:00 [pubmed]
PHST- 2009/05/14 09:00 [medline]
AID - S1053-8119(08)01301-3 [pii]
AID - 10.1016/j.neuroimage.2008.12.031 [doi]
PST - ppublish
SO  - Neuroimage. 2009 Apr 1;45(2):463-9. doi: 10.1016/j.neuroimage.2008.12.031. Epub 
      2008 Dec 30.