Showing posts with label OFC. Show all posts
Showing posts with label OFC. Show all posts

Thursday, July 10, 2008

ARTICLE UPDATE - Distinguishing expected negative outcomes from preparatory control in the human orbitofrontal cortex.

Ursu S, Clark KA, Stenger VA, Carter CS.

Brain Research, in press

The human orbitofrontal cortex (OFC) plays a critical role in adapting behavior according to the context provided by expected outcomes of actions. However, several aspects of this function are still poorly understood. In particular, it is unclear to what degree any subdivisions of the OFC are specifically engaged when negatively valenced outcomes are expected, and to what extent such areas might be involved in preparatory active control of behavior. We examined these issues in two complementary functional magnetic resonance imaging (fMRI) studies in which we simultaneously and independently manipulated monetary incentives for correct performance, and demands for active preparation of cognitive control. In both experiments, preparation for performance was associated with lateral PFC activity in response to high incentives, regardless of their valence, as well as in response to increased task demands. In contrast, areas of the OFC centered around the lateral orbital sulcus responded maximally to negatively perceived prospects, even when such prospects were associated with decreases in preparatory cognitive control. These results provide direct support for theoretical models which posit that the OFC contributes to behavioral regulation by representing the value of anticipated outcomes, but does not implement active control aimed at avoiding or pursuing outcomes. Furthermore, they provide additional converging evidence that the lateral OFC is involved in representing specifically the affective impact of anticipated negative outcomes.

Monday, April 07, 2008

ARTICLE UPDATE - Working Memory for Social Cues Recruits Orbitofrontal Cortex and Amygdala: A Functional Magnetic Resonance Imaging Study of Delayed M

Lopresti ML, Schon K, Tricarico MD, Swisher JD, Celone KA, Stern CE.

The Journal of Neuroscience, 28, 3718-3728.

During everyday interactions, we continuously monitor and maintain information about different individuals and their changing emotions in memory. Yet to date, working memory (WM) studies have primarily focused on mechanisms for maintaining face identity, but not emotional expression, and studies investigating the neural basis of emotion have focused on transient activity, not delay related activity. The goal of this functional magnetic resonance imaging study was to investigate WM for two critical social cues: identity and emotion. Subjects performed a delayed match-to-sample task that required them to match either the emotional expression or the identity of a face after a 10 s delay. Neuroanatomically, our predictions focused on the orbitofrontal cortex (OFC) and the amygdala, as these regions have previously been implicated in emotional processing and long-term memory, and studies have demonstrated sustained OFC and medial temporal lobe activity during visual WM. Consistent with previous studies, transient activity during the sample period representing emotion and identity was found in the superior temporal sulcus and inferior occipital cortex, respectively. Sustained delay-period activity was evident in OFC, amygdala, and hippocampus, for both emotion and identity trials. These results suggest that, although initial processing of emotion and identity is accomplished in anatomically segregated temporal and occipital regions, sustained delay related memory for these two critical features is held by the OFC, amygdala and hippocampus. These regions share rich connections, and have been shown previously to be necessary for binding features together in long-term memory. Our results suggest a role for these regions in active maintenance as well.

Tuesday, January 29, 2008

ARTICLE UPDATE - The neural correlates of the affective response to unreciprocated cooperation.

Rilling JK, Goldsmith DR, Glenn AL, Jairam MR, Elfenbein HA, Dagenais JE, Murdock CD, Pagnoni G.

Neuropsychologia, in press

Humans excel at reciprocal altruism in which two individuals exchange altruistic acts to their mutual advantage. The evolutionary stability of this system depends on recognition of and discrimination against non-reciprocators, and the human mind is apparently specialized for detecting non-reciprocators. Here we investigate the neural response to non-reciprocation of cooperation by imaging human subjects with fMRI as they play an iterated Prisoner's dilemma game with two assumed human partners. Unreciprocated cooperation was associated with greater activity in bilateral anterior insula, left hippocampus and left lingual gyrus, compared with reciprocated cooperation. These areas were also more responsive to unreciprocated cooperation than to unsuccessful risk taking in a non-social context. Finally, functional connectivity between anterior insula and lateral orbitofrontal cortex (OFC) in response to unreciprocated cooperation predicted subsequent defection. The anterior insula is involved in awareness of visceral, autonomic feedback from the body and, in concert with the lateral orbitofrontal cortex, may be responsible for negative feeling states that bias subsequent social decision making against cooperation with a non-reciprocating partner.

Friday, May 11, 2007

ARTICLE UPDATE - Brain, emotion and decision making: the paradigmatic example of regret

Giorgio Coricelli, Raymond J. Dolan, and Angela Sirigu

Trends in Cognitive Sciences, in press

Human decisions cannot be explained solely by rational imperatives but are strongly influenced by emotion. Theoretical and behavioral studies provide a sound empirical basis to the impact of the emotion of regret in guiding choice behavior. Recent neuropsychological and neuroimaging data have stressed the fundamental role of the orbitofrontal cortex in mediating the experience of regret. Functional magnetic resonance imaging data indicate that reactivation of activity within the orbitofrontal cortex and amygdala occurring during the phase of choice, when the brain is anticipating possible future consequences of decisions, characterizes the anticipation of regret. In turn, these patterns reflect learning based on cumulative emotional experience. Moreover, affective consequences can induce specific mechanisms of cognitive control of the choice processes, involving reinforcement or avoidance of the experienced behavior.

Friday, March 09, 2007

ARTICLE UPDATE - Contrasting roles for cingulate and orbitofrontal cortex in decisions and social behaviour.

.F.S. Rushworth, T.E.J. Behrens, P.H. Rudebeck and M.E. Walton

Trends in Cognitive Sciences, in press

There is general acknowledgement that both the anterior cingulate and orbitofrontal cortex are implicated in reinforcement-guided decision making, and emotion and social behaviour. Despite the interest that these areas generate in both the cognitive neuroscience laboratory and the psychiatric clinic, ideas about the distinctive contributions made by each have only recently begun to emerge. This reflects an increasing understanding of the component processes that underlie reinforcement-guided decision making, such as the representation of reinforcement expectations, the exploration, updating and representation of action values, and the appreciation that choices are guided not just by the prospect of reward but also by the costs that action entails. Evidence is emerging to suggest that the anterior cingulate and orbitofrontal cortex make distinct contributions to each of these aspects of decision making.