PMID- 16160096
OWN - NLM
STAT- MEDLINE
DCOM- 20051230
LR  - 20071114
IS  - 0022-3077 (Print)
IS  - 0022-3077 (Linking)
VI  - 94
IP  - 4
DP  - 2005 Oct
TI  - Trial-to-trial variability and its effect on time-varying dependency between two 
      neurons.
PG  - 2928-39
AB  - The joint peristimulus time histogram (JPSTH) and cross-correlogram provide a 
      visual representation of correlated activity for a pair of neurons, and the way 
      this activity may increase or decrease over time. In a companion paper we showed 
      how a Bootstrap evaluation of the peaks in the smoothed diagonals of the JPSTH 
      may be used to establish the likely validity of apparent time-varying 
      correlation. As noted in earlier studies by Brody and Ben-Shaul et al., 
      trial-to-trial variation can confound correlation and synchrony effects. In this 
      paper we elaborate on that observation, and present a method of estimating the 
      time-dependent trial-to-trial variation in spike trains that may exceed the 
      natural variation displayed by Poisson and non-Poisson point processes. The 
      statistical problem is somewhat subtle because relatively few spikes per trial 
      are available for estimating a firing-rate function that fluctuates over time. 
      The method developed here decomposes the spike-train variability into a 
      stimulus-related component and a trial-specific component, allowing many degrees 
      of freedom to characterize the former while assuming a small number suffices to 
      characterize the latter. The Bootstrap significance test of the companion paper 
      is then modified to accommodate these general excitability effects. This 
      methodology allows an investigator to assess whether excitability effects are 
      constant or time-varying, and whether they are shared by two neurons. In data 
      from two V1 neurons we find that highly statistically significant evidence of 
      dependency disappears after adjustment for time-varying trial-to-trial variation.
FAU - Ventura, Valerie
AU  - Ventura V
AD  - Department of Statistics, Carnegie Mellon University, Pittsburgh, PA 15213, USA. 
      vventura@stat.cmu.edu
FAU - Cai, Can
AU  - Cai C
FAU - Kass, Robert E
AU  - Kass RE
LA  - eng
GR  - MH-64537/MH/NIMH NIH HHS/United States
GR  - N01-NS-2-2346/NS/NINDS NIH HHS/United States
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Neurophysiol
JT  - Journal of neurophysiology
JID - 0375404
SB  - IM
MH  - Action Potentials/*physiology
MH  - Animals
MH  - Computer Simulation
MH  - Electrophysiology/methods
MH  - Membrane Potentials
MH  - *Models, Neurological
MH  - Neurons/classification/*physiology
MH  - Photic Stimulation/methods
MH  - Reaction Time/*physiology
MH  - Synaptic Transmission/*physiology
MH  - Time Factors
EDAT- 2005/09/15 09:00
MHDA- 2005/12/31 09:00
CRDT- 2005/09/15 09:00
PHST- 2005/09/15 09:00 [pubmed]
PHST- 2005/12/31 09:00 [medline]
PHST- 2005/09/15 09:00 [entrez]
AID - 94/4/2928 [pii]
AID - 10.1152/jn.00644.2004 [doi]
PST - ppublish
SO  - J Neurophysiol. 2005 Oct;94(4):2928-39. doi: 10.1152/jn.00644.2004.