Thu, 21 Aug 2008 21:34:55 BST CiteULike: di oamg acc http://www.citeulike.org/user/oamg/tag/acc CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/oamg/article/2285145 <i>Neuron, Vol. 57, No. 2. (24 January 2008), pp. 314-325.</i><br /><br />Summary Rapid optimization of behavior requires decisions about when to explore and when to exploit discovered resources. The mechanisms that lead to fast adaptations and their interaction with action valuation are a central issue. We show here that the anterior cingulate cortex (ACC) encodes multiple feedbacks devoted to exploration and its immediate termination. In a task that alternates exploration and exploitation periods, the ACC monitored negative and positive outcomes relevant for different adaptations. In particular, it produced signals specific of the first reward, i.e., the end of exploration. Those signals disappeared in exploitation periods but immediately transferred to the initiation of trials--a transfer comparable to learning phenomena observed for dopaminergic neurons. Importantly, these were also observed for high gamma oscillations of local field potentials shown to correlate with brain imaging signal. Thus, mechanisms of action valuation and monitoring of events/actions are combined for rapid behavioral regulation. Behavioral Shifts and Action Valuation in the Anterior Cingulate Cortex Rene Quilodran Marie Rothe Emmanuel Procyk doi:10.1016/j.neuron.2007.11.031 Neuron, Vol. 57, No. 2. (24 January 2008), pp. 314-325. 2008-01-24T15:58:11-00:00 2008 Neuron 57 2 314 325 acc action_value behavioral_shifts cev http://www.citeulike.org/user/oamg/article/472733 <i>J Neurosci, Vol. 23, No. 22. (3 September 2003), pp. 8002-8012.</i><br /><br />Noninvasive imaging techniques showed that the anterior cingulate cortex is related to higher-order cognitive and motor-related functions in humans. To elucidate the cellular mechanism of such cingulate functions, single-unit activity was recorded from three cingulate motor areas of macaque monkeys performing delayed conditional Go/No-go discrimination tasks using spatial (location) and nonspatial (color) visual cues. Unlike prefrontal neurons, only a few neurons coded the visual information on individual features (e.g., "left" or "red") in all of the rostral (CMAr), dorsal (CMAd), and ventral (CMAv) cingulate motor areas. Instead, many neurons in the CMAr exhibited the attention-like activity anticipating the second (conditioned) visual cues, with the specificity to visual category ("location" or "color"). In addition, there were a number of CMAr neurons specific to motor response (Go or No-go) in relation to the second visual cues. Some of the visual category-specific neurons in the CMAr further displayed the motor response-specific activity. On the other hand, many of the task-related CMAd and CMAv neurons seemed to be implicated directly in motor functions, such as preparation and execution of movements in Go trials. The present results suggest that the CMAr neurons may participate in cognitive and motor functions of "attention for action" and "response selection" for an appropriate action according to an intention, whereas the CMAd and CMAv neurons may be involved in "motor preparation and execution". Neural coding of "attention for action" and "response selection" in primate anterior cingulate cortex. Y Isomura Y Ito T Akazawa A Nambu M Takada J Neurosci, Vol. 23, No. 22. (3 September 2003), pp. 8002-8012. 2006-01-20T16:49:41-00:00 2003 J Neurosci 1529-2401 23 22 8002 8012 acc attention_for_action cingulate response_selection