The Journal of Neuroscience, October 15, 2008, 28(42):10618-10630; doi:10.1523/JNEUROSCI.3418-08.2008
Previous Article | Next Article 
Behavioral/Systems/Cognitive
Correlations between Groups of Premotor Neurons Carry Information about Prehension
Eran Stark,1
Amir Globerson,2
Itay Asher,1,3 and
Moshe Abeles1,3,4
1Department of Physiology, Hadassah Medical School, Hebrew University, Jerusalem 91120, Israel, 2Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, 3Interdisciplinary Center for Neural Computation, Hebrew University, Jerusalem 91904, Israel, and 4Gonda Brain Research Center, Bar-Ilan University, Ramat-Gan 52900, Israel
Correspondence should be addressed to Eran Stark, Department of Physiology, Hadassah Medical School, Hebrew University, Jerusalem 91120, Israel. Email: eran.stark{at}ekmd.huji.ac.il
How distinct parameters are bound together in brain activity is unknown. Combination coding by interneuronal interactions is one possibility, but, to coordinate parameters, interactions between neuronal pairs must carry information about them. To address this issue, we recorded neural activity from multiple sites in the premotor cortices of monkeys that memorized reach direction and grasp type followed by actual prehension. We found that correlations between individual spiking neurons are generally weak and carry little information about prehension. In contrast, correlations and synchronous interactions between small groups of neurons, quantified by multiunit activity (MUA), are an order of magnitude stronger. A substantial fraction of the information carried by pairwise interactions between MUAs is about combinations of reach and grasp. This contrasts with the information carried by individual neurons and individual MUAs, which is mainly about reach and/or grasp but much less about their combinations. The main contribution of pairwise interactions to the coding of reach–grasp combinations is when animals memorize prehension parameters, consistent with an internal composite representation. The informative interactions between neuronal groups may facilitate the coordination of reach and grasp into coherent prehension.
Key words: encoding; extracellular recordings; information theory; macaque monkey; multiunit activity; premotor cortex
Received July 21, 2008;
revised Sept. 1, 2008;
accepted Sept. 2, 2008.
Correspondence should be addressed to Eran Stark, Department of Physiology, Hadassah Medical School, Hebrew University, Jerusalem 91120, Israel. Email: eran.stark{at}ekmd.huji.ac.il
This article has been cited by other articles:

|
 |

|
 |
 
A. Globerson, E. Stark, E. Vaadia, and N. Tishby
The minimum information principle and its application to neural code analysis
PNAS,
March 3, 2009;
106(9):
3490 - 3495.
[Abstract]
[Full Text]
[PDF]
|
 |
|