| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
The Journal of Neurophysiology Vol. 86 No. 4 October 2001, pp. 1700-1716
Copyright ©2001 by the American Physiological Society
1School of Psychology, University of St. Andrews, Fife KY16 9JU, United Kingdom; 2Department of Neuroscience, Brown University, Providence, Rhode Island 02912; and 3National Institute of Mental Health/National Institutes of Health, Bethesda, Maryland 20892
Oram, Mike W.,
Nicholas
G. Hatsopoulos,
Barry J. Richmond, and
John P. Donoghue.
Excess Synchrony in Motor Cortical Neurons Provides Redundant
Direction Information With That From Coarse Temporal Measures. J. Neurophysiol. 86: 1700-1716, 2001. Previous studies have shown that measures of fine temporal
correlation, such as synchronous spikes, across responses of motor cortical neurons carries more directional information than that predicted from statistically independent neurons. It is also known, however, that the coarse temporal measures of responses, such as spike
count, are not independent. We therefore examined whether the
information carried by coincident firing was related to that of
coarsely defined spike counts and their correlation. Synchronous spikes
were counted in the responses from 94 pairs of simultaneously recorded
neurons in primary motor cortex (MI) while monkeys performed arm
movement tasks. Direct measurement of the movement-related information
indicated that the coincident spikes (1- to 5-ms precision) carry
~10% of the information carried by a code of the two spike counts.
Inclusion of the numbers of synchronous spikes did not add information
to that available from the spike counts and their coarse temporal
correlation. To assess the significance of the numbers of coincident
spikes, we extended the stochastic spike count matched (SCM) model to
include correlations between spike counts of the individual neural
responses and slow temporal dependencies within neural responses (~30
Hz bandwidth). The extended SCM model underestimated the numbers of
synchronous spikes. Therefore as with previous studies, we found that
there were more synchronous spikes in the neural data than could be
accounted for by this stochastic model. However, the SCM model accounts
for most (R2 = 0.93 ± 0.05, mean ± SE) of the differences in the observed number of
synchronous spikes to different directions of arm movement, indicating
that synchronous spiking is directly related to spike counts and their
broad correlation. Further, this model supports the information
theoretic analysis that the synchronous spikes do not provide
directional information beyond that available from the firing rates of
the same pool of directionally tuned MI neurons. These results show
that detection of precisely timed spike patterns above chance levels
does not imply that those spike patterns carry information unavailable
from coarser population codes but leaves open the possibility that
excess synchrony carries other forms of information or serves other
roles in cortical information processing not studied here.
This article has been cited by other articles:
|
|
 |
|
  J. Rickert, A. Riehle, A. Aertsen, S. Rotter, and M. P. Nawrot Dynamic Encoding of Movement Direction in Motor Cortical Neurons J. Neurosci., November 4, 2009; 29(44): 13870 - 13882. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. L. Jacobs, G. Fridman, R. M. Douglas, N. M. Alam, Peter. E. Latham, G. T. Prusky, and S. Nirenberg Ruling out and ruling in neural codes PNAS, April 7, 2009; 106(14): 5936 - 5941. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. T. Rolls, F. Grabenhorst, and L. Franco Prediction of Subjective Affective State From Brain Activations J Neurophysiol, March 1, 2009; 101(3): 1294 - 1308. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Montani, A. Kohn, M. A. Smith, and S. R. Schultz The Role of Correlations in Direction and Contrast Coding in the Primary Visual Cortex J. Neurosci., February 28, 2007; 27(9): 2338 - 2348. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Luczak, P. Bartho, S. L. Marguet, G. Buzsaki, and K. D. Harris Sequential structure of neocortical spontaneous activity in vivo PNAS, January 2, 2007; 104(1): 347 - 352. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. B. Averbeck and D. Lee Effects of Noise Correlations on Information Encoding and Decoding J Neurophysiol, June 1, 2006; 95(6): 3633 - 3644. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. M. Churchland, B. M. Yu, S. I. Ryu, G. Santhanam, and K. V. Shenoy Neural variability in premotor cortex provides a signature of motor preparation. J. Neurosci., April 5, 2006; 26(14): 3697 - 3712. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Lehmkuhle, R. A. Normann, and E. M. Maynard Trial-by-Trial Discrimination of Three Enantiomer Pairs by Neural Ensembles in Mammalian Olfactory Bulb J Neurophysiol, March 1, 2006; 95(3): 1369 - 1379. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. H. Schieber and G. Rivlis A Spectrum From Pure Post-Spike Effects to Synchrony Effects in Spike-Triggered Averages of Electromyographic Activity During Skilled Finger Movements J Neurophysiol, November 1, 2005; 94(5): 3325 - 3341. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. E. Latham and S. Nirenberg Synergy, Redundancy, and Independence in Population Codes, Revisited J. Neurosci., May 25, 2005; 25(21): 5195 - 5206. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. C. Aggelopoulos, L. Franco, and E. T. Rolls Object Perception in Natural Scenes: Encoding by Inferior Temporal Cortex Simultaneously Recorded Neurons J Neurophysiol, March 1, 2005; 93(3): 1342 - 1357. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Paninski, S. Shoham, M. R. Fellows, N. G. Hatsopoulos, and J. P. Donoghue Superlinear Population Encoding of Dynamic Hand Trajectory in Primary Motor Cortex J. Neurosci., September 29, 2004; 24(39): 8551 - 8561. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Prut and S. I. Perlmutter Firing Properties of Spinal Interneurons during Voluntary Movement. II. Interactions between Spinal Neurons J. Neurosci., October 22, 2003; 23(29): 9611 - 9619. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. B. Averbeck and D. Lee Neural Noise and Movement-Related Codes in the Macaque Supplementary Motor Area J. Neurosci., August 20, 2003; 23(20): 7630 - 7641. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Nirenberg and P. E. Latham Decoding neuronal spike trains: How important are correlations? PNAS, June 10, 2003; 100(12): 7348 - 7353. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. C. Wiener and B. J. Richmond Decoding Spike Trains Instant by Instant Using Order Statistics and the Mixture-of-Poissons Model J. Neurosci., March 15, 2003; 23(6): 2394 - 2406. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Constantinidis and P. S. Goldman-Rakic Correlated Discharges Among Putative Pyramidal Neurons and Interneurons in the Primate Prefrontal Cortex J Neurophysiol, December 1, 2002; 88(6): 3487 - 3497. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
