Whether driving a car, shopping for food, or paying attention in a classroom of boisterous teenagers, it’s often hard to maintain focus on goals in the face of distraction. Brain imaging studies in ...humans implicate the dorsal anterior cingulate cortex (dACC) in regulating the conflict between goals and distractors. Here we show that single dACC neurons signal conflict between task goals and distractors in the rhesus macaque, particularly for biologically relevant social stimuli. For some neurons, task conflict signals predicted subsequent changes in pupil size—a peripheral index of arousal linked to noradrenergic tone—associated with reduced distractor interference. dACC neurons also responded to errors, and these signals predicted adjustments in pupil size. These findings provide the first neurophysiological endorsement of the hypothesis that dACC regulates conflict, in part, via modulation of pupil-linked processes such as arousal.
•Conflict is signaled in rhesus macaque dorsal anterior cingulate cortex (dACC)•Conflict signals in macaque dACC are linked to task, rather than action conflict•dACC neurons also track pupil size and predict adjustments in pupil size•dACC responses to both conflict and errors are linked to pupil size within neurons
Cingulate conflict signals have been thought of as uniquely human, but Ebitz et al. report conflict signals in macaque neurons. These neurons predicted task-facilitating adjustments in arousal in response to both conflict and errors, suggesting a unified function for dACC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The US National Academy of Sciences reports rising mortality for US adults, most steeply for White adults with a secondary education or less. The rise is largely attributable to deaths of despair ...(suicide and poisoning by alcohol and drugs) with strong contributions from the cardiovascular effects of rising obesity. Although the report does acknowledge a crisis, it proposes mild measures to manage it, such as strengthening programs to support recovery, prevent relapse, increase resilience, and perform more research toward clinically useful definitions of despair. The US National Academy of Sciences report notes that mortality is decreasing in a control group of 16 wealthy nations (including countries in Western Europe, Canada, Australia, and Japan), but it does not ask what protects those nations from despair. It has been observed that human beings are constrained by evolutionary strategy (ie, huge brain, prolonged physical and emotional dependence, education beyond adolescence for professional skills, and extended adult learning) to require communal support at all stages of the life cycle. Without support, difficulties accumulate until there seems to be no way forward. The 16 wealthy nations provide communal assistance at every stage, thus facilitating diverse paths forward and protecting individuals and families from despair. The US could solve its health crisis by adopting the best practices of the 16-nation control group.
Neuroeconomics applies models from economics and psychology to inform neurobiological studies of choice. This approach has revealed neural signatures of concepts like value, risk, and ambiguity, ...which are known to influence decision making. Such observations have led theorists to hypothesize a single, unified decision process that mediates choice behavior via a common neural currency for outcomes like food, money, or social praise. In parallel, recent neuroethological studies of decision making have focused on natural behaviors like foraging, mate choice, and social interactions. These decisions strongly impact evolutionary fitness and thus are likely to have played a key role in shaping the neural circuits that mediate decision making. This approach has revealed a suite of computational motifs that appear to be shared across a wide variety of organisms. We argue that the existence of deep homologies in the neural circuits mediating choice may have profound implications for understanding human decision making in health and disease.
Most work on the neuroscience of decision making has been based on a rational choice framework borrowed from economics. Pearson et al. review recent studies suggesting that natural behaviors may offer a more biologically grounded view that facilitates comparisons across species.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Deciding when to leave a depleting resource to exploit another is a fundamental problem for all decision makers. The neuronal mechanisms mediating patch-leaving decisions remain unknown. We found ...that neurons in primate (Macaca mulatta) dorsal anterior cingulate cortex, an area that is linked to reward monitoring and executive control, encode a decision variable signaling the relative value of leaving a depleting resource for a new one. Neurons fired during each sequential decision to stay in a patch and, for each travel time, these responses reached a fixed threshold for patch-leaving. Longer travel times reduced the gain of neural responses for choosing to stay in a patch and increased the firing rate threshold mandating patch-leaving. These modulations more closely matched behavioral decisions than any single task variable. These findings portend an understanding of the neural basis of foraging decisions and endorse the unification of theoretical and experimental work in ecology and neuroscience.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The neuropeptides oxytocin (OT) and arginine vasopressin (AVP) influence social functions in many mammals. In humans and rhesus macaques, OT delivered intranasally can promote prosocial behavior in ...certain contexts. Yet the precise neural mechanisms mediating these behavioral effects remain unclear. Here we show that treating a group of male macaque monkeys intranasally with aerosolized OT relaxes their spontaneous social interactions with other monkeys. OT reduces differences in social behavior between dominant and subordinate monkeys, thereby flattening the status hierarchy. OT also increases behavioral synchrony within a pair. Intranasal delivery of aerosolized AVP reproduces the effects of OT with greater efficacy. Remarkably, all behavioral effects are replicated when OT or AVP is injected focally into the anterior cingulate gyrus (ACCg), a brain area linked to empathy and other-regarding behavior. ACCg lacks OT receptors but is rich in AVP receptors, suggesting exogenous OT may shape social behavior, in part, via nonspecific binding. Notably, OT and AVP alter behaviors of both the treated monkey and his untreated partner, consistent with enhanced feedback through reciprocal social interactions. These findings bear important implications for use of OT in both basic research and as a therapy for social impairments in neurodevelopmental disorders.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Primate evolution produced an increased capacity to respond flexibly to varying social contexts as well as expansion of the prefrontal cortex 1, 2. Despite this association, how prefrontal neurons ...respond to social information remains virtually unknown. People with damage to their orbitofrontal cortex (OFC) struggle to recognize facial expressions 3, 4, make poor social judgments 5, 6, and frequently make social faux pas 7, 8. Here we test explicitly whether neurons in primate OFC signal social information and, if so, how such signals compare with responses to primary fluid rewards. We find that OFC neurons distinguish images that belong to socially defined categories, such as female perinea and faces, as well as the social dominance of those faces. These modulations signaled both how much monkeys valued these pictures and their interest in continuing to view them. Far more neurons signaled social category than signaled fluid value, despite the stronger impact of fluid reward on monkeys’ choices. These findings indicate that OFC represents both the motivational value and attentional priority of other individuals, thus contributing to both the acquisition of information about others and subsequent social decisions. Our results betray a fundamental disconnect between preferences expressed through overt choice, which were primarily driven by the desire for more fluid, and preferential neuronal processing, which favored social computations.
► OFC neurons respond to social visual stimuli ► OFC neurons differentiate between socially defined classes of images ► OFC neurons signal the value of social information for making decisions ► More OFC neurons convey social information than fluid reward magnitude
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Many decisions involve uncertainty, or imperfect knowledge about how choices lead to outcomes. Colloquial notions of uncertainty, particularly when describing a decision as 'risky', often carry ...connotations of potential danger as well. Gambling on a long shot, whether a horse at the racetrack or a foreign oil company in a hedge fund, can have negative consequences, but the impact of uncertainty on decision making extends beyond gambling. Indeed, uncertainty in some form pervades nearly all our choices in daily life. Stepping into traffic to hail a cab, braving an ice storm to be the first at work, or dating the boss's son or daughter also offer potentially great windfalls, at the expense of surety. We continually face trade-offs between options that promise safety and others that offer an uncertain potential for jackpot or bust. When mechanisms for dealing with uncertain outcomes fail, as in mental disorders such as problem gambling or addiction, the results can be disastrous. Thus, understanding decision making-indeed, understanding behavior itself-requires knowing how the brain responds to and uses information about uncertainty.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The capacity and motivation to be social is a key component of the human adaptive behavioral repertoire. Recent research has identified social behaviors remarkably similar to our own in other ...animals, including empathy, consolation, cooperation, and strategic deception. Moreover, neurobiological studies in humans, nonhuman primates, and rodents have identified shared brain structures (the so-called ‘social brain’) apparently specialized to mediate such functions. Neuromodulators may regulate social interactions by ‘tuning’ the social brain, with important implications for treating social impairments. Here, we survey recent findings in social neuroscience from a comparative perspective, and conclude that the very social behaviors that make us human emerge from mechanisms shared widely with other animals, as well as some that appear to be unique to humans and other primates.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Social decisions depend on reliable information about others. Consequently, social primates are motivated to acquire information about the identity, social status, and reproductive quality of others ...1. Neurophysiological 2 and neuroimaging 3, 4 studies implicate the striatum in the motivational control of behavior. Neuroimaging studies specifically implicate the ventromedial striatum in signaling motivational aspects of social interaction 5. Despite this evidence, precisely how striatal neurons encode social information remains unknown. Therefore, we probed the activity of single striatal neurons in monkeys choosing between visual social information at the potential expense of fluid reward. We show for the first time that a population of neurons located primarily in medial striatum selectively signals social information. Surprisingly, representation of social information was unrelated to simultaneously expressed social preferences. A largely nonoverlapping population of neurons that was not restricted to the medial striatum signaled information about fluid reward. Our findings demonstrate that information about social context and nutritive reward are maintained largely independently in striatum, even when both influence decisions to execute a single action.
► Single neurons in striatum encode social information ► Typically, striatal neurons signal social or fluid information, but not both ► Topographically distinct information channels process social and fluid reward
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Many species use social interactions to cope with challenges in their environment and a growing number of studies show that individuals which are well-connected to their group have higher fitness ...than socially isolated individuals. However, there are many ways to be 'well-connected' and it is unclear which aspects of sociality drive fitness benefits. Being well-connected can be conceptualized in four main ways: individuals can be socially integrated by engaging in a high rate of social behaviour or having many partners; they can have strong and stable connections to favoured partners; they can indirectly connect to the broader group structure; or directly engage in a high rate of beneficial behaviours, such as grooming. In this study, we use survival models and long-term data in adult female rhesus macaques (
) to compare the fitness outcomes of multiple measures of social connectedness. Females that maintained strong connections to favoured partners had the highest relative survival probability, as did females well-integrated owing to forming many weak connections. We found no survival benefits to being structurally well-connected or engaging in high rates of grooming. Being well-connected to favoured partners could provide fitness benefits by, for example, increasing the efficacy of coordinated or mutualistic behaviours.
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