A Caltech Library Service

Supplementary Motor Area Encodes Reward Expectancy in Eye-Movement Tasks

Campos, M. and Breznen, B. and Bernheim, K. and Andersen, R. A. (2005) Supplementary Motor Area Encodes Reward Expectancy in Eye-Movement Tasks. Journal of Neurophysiology, 94 (2). pp. 1325-1335. ISSN 0022-3077. doi:10.1152/jn.00022.2005.

[img] PDF - Accepted Version
See Usage Policy.


Use this Persistent URL to link to this item:


Neural activity signifying the expectation of reward has been found recently in many parts of the brain, including midbrain and cortical structures. These signals can facilitate goal-directed behavior or the learning of new skills based on reinforcements. Here we show that neurons in the supplementary motor area (SMA), an area concerned with movements of the body and limbs, also carry a reward expectancy signal in the postsaccadic period of oculomotor tasks. While the monkeys performed blocks of memory-guided and object-based saccades, the neurons discharged a burst after a ∼200-ms delay following the target-acquiring saccade in the memory task but often fired concurrently with the target-acquiring saccade in the object task. The hypothesis that this postsaccadic bursting activity reflects the expectation of a reward was tested with a series of manipulations to the memory-guided saccade task. It was found that although the timing of the bursting activity corresponds to a visual feedback stimulus, the visual feedback is not required for the neurons to discharge a burst. Second, blocks of no-reward trials reveal an extinction of the bursting activity as the monkeys come to understand that they would not be rewarded for properly generated saccades. Finally, the delivery of unexpected rewards confirmed that in many of the neurons, the activity is not related to a motor plan to acquire the reward (e.g., licking). Thus we conclude that reward expectancy is represented by the activity of SMA neurons, even in the context of an oculomotor task. These results suggest that the reward expectancy signal is broadcast over a large extent of motor cortex, and may facilitate the learning of new, coordinated behavior between different body parts.

Item Type:Article
Related URLs:
URLURL TypeDescription
Andersen, R. A.0000-0002-7947-0472
Additional Information:© 2005 by the American Physiological Society. Received 10 January 2005; Accepted 13 April 2005; Published online 1 August 2005; Published in print 1 August 2005. This work was supported by the National Institutes of Health and a James G. Boswell Professorship. The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Funding AgencyGrant Number
James G. Boswell FoundationUNSPECIFIED
Issue or Number:2
Record Number:CaltechAUTHORS:20200401-081214414
Persistent URL:
Official Citation:Supplementary Motor Area Encodes Reward Expectancy in Eye-Movement Tasks. M. Campos, B. Breznen, K. Bernheim, and R. A. Andersen. Journal of Neurophysiology 2005 94:2, 1325-1335; doi: 10.1152/jn.00022.2005
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:102221
Deposited By: Tony Diaz
Deposited On:01 Apr 2020 15:37
Last Modified:16 Nov 2021 18:09

Repository Staff Only: item control page