PMID- 10746121
OWN - NLM
STAT- MEDLINE
DCOM- 20000420
LR  - 20190728
IS  - 0042-6989 (Print)
IS  - 0042-6989 (Linking)
VI  - 39
IP  - 21
DP  - 1999 Oct
TI  - Spatio-temporal tuning of VEPs: effect of mode of stimulation.
PG  - 3491-7
AB  - The spatial tuning function of the 8 Hz reversal Visual Evoked Potential (VEP) is 
      frequently bimodal. This amplitude 'notch' largely disappears with 16 Hz pattern 
      onset-offset (on-off) stimulation. To investigate the effect of temporal 
      frequency on this phenomenon, we tested seven subjects using a range of rates 
      centred on 8 Hz (reversal) and 16 Hz (on-off). With reversal, a deep notch was 
      present at all temporal frequencies. A much shallower notch was evident with 
      on-off. The on-off and reversal functions differed only in their low spatial 
      frequency branches (below 4.5 c deg-1) where, as temporal frequency decreased, 
      the reversal response was reduced by 50%, whilst the on-off responses doubled in 
      amplitude. Thus, although they behave differently with on-off and reversal, 
      multiple spatial frequency mechanisms are evident with both forms of stimulation.
FAU - Parry, N R
AU  - Parry NR
AD  - Vision Science Centre, Manchester Royal Eye Hospital, UK. neil.parry@man.ac.uk
FAU - Murray, I J
AU  - Murray IJ
FAU - Hadjizenonos, C
AU  - Hadjizenonos C
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Vision Res
JT  - Vision research
JID - 0417402
SB  - IM
MH  - Contrast Sensitivity/physiology
MH  - Evoked Potentials, Visual/*physiology
MH  - Humans
MH  - Photic Stimulation
MH  - Time Factors
EDAT- 2000/04/04 09:00
MHDA- 2000/04/25 09:00
CRDT- 2000/04/04 09:00
PHST- 2000/04/04 09:00 [pubmed]
PHST- 2000/04/25 09:00 [medline]
PHST- 2000/04/04 09:00 [entrez]
AID - S0042-6989(99)00098-X [pii]
AID - 10.1016/s0042-6989(99)00098-x [doi]
PST - ppublish
SO  - Vision Res. 1999 Oct;39(21):3491-7. doi: 10.1016/s0042-6989(99)00098-x.