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Many recent studies indicate that control of decisions and actions is integrated during interactive behavior. Among these, several carried out in humans and monkeys conclude that there is a coregulation of choices and movements. Another perspective, based on human data only, proposes a decoupled control of decision duration and movement speed, allowing, for instance, trading decision duration for movement duration when time pressure increases. Crucially, it is not currently known whether this ability to flexibly dissociate decision duration from movement speed is specific to humans, whether it can vary depending on the context in which a task is performed, and whether it is stable over time. These are important questions to address, especially to rely on monkey electrophysiology to infer the neural mechanisms of decision-action coordination in humans. To do so, we trained two macaque monkeys in a perceptual decision-making task and analyzed data collected over multiple behavioral sessions. Our findings reveal a strong and complex relationship between decision duration and movement vigor. Decision duration and action duration can covary but also "compensate" each other. Such integrated but decoupled control of decisions and actions aligns with recent studies in humans, validating the monkey model in electrophysiology as a means of inferring neural mechanisms in humans. Crucially, we demonstrate for the first time that this control can evolve with experience, in an adapted manner. Together, the present findings contribute to deepening our understanding of the integrated control of decisions and actions during interactive behavior. NEW & NOTEWORTHY: The mechanism by which the integrated control of decisions and actions occurs, coupled or interactive but decoupled, is debated. In the present study, we show in monkeys that decisions and actions influence each other in a decoupled way. For the first time, we also demonstrate that this control can evolve depending the subject's experience, allowing the trade of movement time for decision time and limiting the temporal discounting of reward value. [ABSTRACT FROM AUTHOR]

Appetitive conditioning plays an important role in the development and maintenance of pornography‐use and gaming disorders. It is assumed that primary and secondary reinforcers are involved in these processes. Despite the common use of pornography and gaming in the general population appetitive conditioning processes in this context are still not well studied. This study aims to compare appetitive conditioning processes using primary (pornographic) and secondary (monetary and gaming‐related) rewards as unconditioned stimuli (UCS) in the general population. Additionally, it investigates the conditioning processes with gaming‐related stimuli as this type of UCS was not used in previous studies. Thirty‐one subjects participated in a differential conditioning procedure in which four geometric symbols were paired with either pornographic, monetary, or gaming‐related rewards or with nothing to become conditioned stimuli (CS + porn, CS + game, CS + money, and CS−) in an functional magnetic resonance imaging study. We observed elevated arousal and valence ratings as well as skin conductance responses for each CS+ condition compared to the CS−. On the neural level, we found activations during the presentation of the CS + porn in the bilateral nucleus accumbens, right medial orbitofrontal cortex, and the right ventral anterior cingulate cortex compared to the CS−, but no significant activations during CS + money and CS + game compared to the CS−. These results indicate that different processes emerge depending on whether primary and secondary rewards are presented separately or together in the same experimental paradigm. Additionally, monetary and gaming‐related stimuli seem to have a lower appetitive value than pornographic rewards. [ABSTRACT FROM AUTHOR]

To identify biobehavioral mechanisms underlying excessive reward consumption, reward valuation-effort (RV-E) assessments should (a) parallel measures in basic science to permit translation from preclinical to clinical studies; (b) quantify constructs dimensionally from healthy to disease states; and (c) hold relevance across different diagnostic categories. To address these aims, we developed a progressive ratio (PR) task whereby RV-E is measured as breakpoint when participants worked for access to playing a game. We evaluated test-retest reliability of breakpoint and convergent and discriminant validity of interpretations of this score against an established PR task for food. In Study 1, female undergraduates (N = 71; 33% racial minority; 28% ethnic minority) completed the game and food tasks in fasted and fed states. In Study 2, women (N = 189; 29% racial minority; 27% ethnic minority) with eating disorders (n = 158) were compared to controls (n = 31) on tasks. Game task breakpoint demonstrated excellent test-retest reliability, intraclass correlation coefficient (ICC) = .91, 95% CI [.80, -.96], over 2 weeks and convergent validity with the fasted food task (r = .51, p < .001). Consistent with animal models, breakpoint was lower in fed compared to fasted states across tasks, B (SE) = 321.01 (552.40), p < .001. Finally, the game task demonstrated discriminant validity from measurement of satiation. In Study 2, women with eating disorders demonstrated higher breakpoint on both tasks compared to controls, and game PR task breakpoint decreased from a fasted to fed state. The game PR task offers a novel approach for translating results from animal models of RV-E into testable hypotheses in nonclinical and clinical samples. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Although overconsumption of high-fat foods is a major driver of weight gain, the neural mechanisms that link the oral sensory properties of dietary fat to reward valuation and eating behavior remain unclear. Here we combine novel food-engineering approaches with functional neuroimaging to show that the human orbitofrontal cortex (OFC) translates oral sensations evoked by high-fat foods into subjective economic valuations that guide eating behavior. Male and female volunteers sampled and evaluated nutrient-controlled liquid foods that varied in fat and sugar (“milkshakes”). During oral food processing, OFC activity encoded a specific oral-sensory parameter that mediated the influence of the foods’ fat content on reward value: the coefficient of sliding friction. Specifically, OFC responses to foods in the mouth reflected the smooth, oily texture (i.e., mouthfeel) produced by fatty liquids on oral surfaces. Distinct activity patterns in OFC encoded the economic values associated with particular foods, which reflected the subjective integration of sliding friction with other food properties (sugar, fat, viscosity). Critically, neural sensitivity of OFC to oral texture predicted individuals’ fat preferences in a naturalistic eating test: individuals whose OFC was more sensitive to fat-related oral texture consumed more fat during ad libitum eating. Our findings suggest that reward systems of the human brain sense dietary fat from oral sliding friction, a mechanical food parameter that likely governs our daily eating experiences by mediating interactions between foods and oral surfaces. These findings identify a specific role for the human OFC in evaluating oral food textures to mediate preference for high-fat foods. [ABSTRACT FROM AUTHOR]

Making good economic and social decisions is essential for individual and social welfare. Decades of research have provided compelling evidence that damage to the ventromedial prefrontal cortex (vmPFC) is associated with dramatic personality changes and impairments in economic and social decision-making. However, whether the vmPFC subserves a unified mechanism in the social and non-social domains remains unclear. When choosing between economic options, the vmPFC is thought to guide decision by encoding value signals that reflect the motivational relevance of the options on a common scale. A recent framework, the "extended common neural currency" hypothesis, suggests that the vmPFC may also assign values to social factors and principles, thereby guiding social decision-making. Although neural value signals have been observed in the vmPFC in both social and non-social studies, it is yet to be determined whether they have a causal influence on behavior or merely correlate with decision-making. In this review, we assess whether lesion studies of patients with vmPFC damage offer evidence for such a causal role of the vmPFC in shaping economic and social behavior. [ABSTRACT FROM AUTHOR]

In conclusion, it seems most likely that the acoustic stimuli have a warning or alerting effect, indicating the reward value of the stimulus and by this preparing a response to the stimulus. The acoustic stimuli carry information about the reward value based on the frequency and sound pressure level information, which in turn will be detectable within few milliseconds after stimulus onset. Keywords: attention; multisensory integration; reward value EN attention multisensory integration reward value 3714 3718 5 10/09/23 20231001 NES 231001 INTRODUCTION The study by Bean, Stein and Rowland, titled "Stimulus value gates multisensory integration" (Bean et al., [1]), comprises a series of experiments focusing on two highly interesting aspects. Thus, during the first few milliseconds of the stimulus presentation, the cat will be able to extract information on the reward value solely based on the auditory stimulus. [Extracted from the article]

Making good economic and social decisions is essential for individual and social welfare. Decades of research have provided compelling evidence that damage to the ventromedial prefrontal cortex (vmPFC) is associated with dramatic personality changes and impairments in economic and social decision-making. However, whether the vmPFC subserves a unified mechanism in the social and non-social domains remains unclear. When choosing between economic options, the vmPFC is thought to guide decision by encoding value signals that reflect the motivational relevance of the options on a common scale. A recent framework, the “extended common neural currency” hypothesis, suggests that the vmPFC may also assign values to social factors and principles, thereby guiding social decision-making. Although neural value signals have been observed in the vmPFC in both social and non-social studies, it is yet to be determined whether they have a causal influence on behavior or merely correlate with decision-making. In this review, we assess whether lesion studies of patients with vmPFC damage offer evidence for such a causal role of the vmPFC in shaping economic and social behavior.

Introduction: Fetal Alcohol Spectrum Disorders (FASD) are the leading cause of preventable developmental disability and are commonly characterized by alterations in executive function. Reversal learning tasks are reliable, crossspecies methods for testing a frequently impaired aspect of executive control, behavioral flexibility. Pre-clinical studies commonly require the use of reinforcers to motivate animals to learn and perform the task. While there are several reinforcers available, the most commonly employed are solid (food pellets) and liquid (sweetened milk) rewards. Previous studies have examined the effects of different solid rewards or liquid dietary content on learning in instrumental responding and found that rodents on liquid reward with higher caloric content performed better with increased response and task acquisition rate. The influence of reinforcer type on reversal learning and how this interacts with developmental insults such as prenatal alcohol exposure (PAE) has not been explored. Methods: We tested whether reinforcer type during learning or reversal would impact an established deficit in PAE mice. Results: We found that all male and female mice on liquid reward, regardless of prenatal exposure were better motivated to learn task behaviors during pretraining. Consistent with previous findings, both male and female PAE mice and Saccharine control mice were able to learn the initial stimulus reward associations irrespective of the reinforcer type. During the initial reversal phase, male PAE mice that received pellet rewards exhibited maladaptive perseverative responding whereas male mice that received liquid rewards performed comparable to their control counterparts. Female PAE mice that received either reinforcer types did not exhibit any deficits on behavioral flexibility. Female saccharine control mice that received liquid, but not pellet, rewards showed increased perseverative responding during the early reversal phase. Discussion: These data suggest that reinforcer type can have a major impact on motivation, and therefore performance, during reversal learning. Highly motivating rewards may mask behavioral deficits seen with more moderately sought rewards and gestational exposure to the non-caloric sweetener, saccharine, can impact behavior motivated by those reinforcers in a sex-dependent manner. [ABSTRACT FROM AUTHOR]

IntroductionFetal Alcohol Spectrum Disorders (FASD) are the leading cause of preventable developmental disability and are commonly characterized by alterations in executive function. Reversal learning tasks are reliable, cross-species methods for testing a frequently impaired aspect of executive control, behavioral flexibility. Pre-clinical studies commonly require the use of reinforcers to motivate animals to learn and perform the task. While there are several reinforcers available, the most commonly employed are solid (food pellets) and liquid (sweetened milk) rewards. Previous studies have examined the effects of different solid rewards or liquid dietary content on learning in instrumental responding and found that rodents on liquid reward with higher caloric content performed better with increased response and task acquisition rate. The influence of reinforcer type on reversal learning and how this interacts with developmental insults such as prenatal alcohol exposure (PAE) has not been explored.MethodsWe tested whether reinforcer type during learning or reversal would impact an established deficit in PAE mice.ResultsWe found that all male and female mice on liquid reward, regardless of prenatal exposure were better motivated to learn task behaviors during pre-training. Consistent with previous findings, both male and female PAE mice and Saccharine control mice were able to learn the initial stimulus reward associations irrespective of the reinforcer type. During the initial reversal phase, male PAE mice that received pellet rewards exhibited maladaptive perseverative responding whereas male mice that received liquid rewards performed comparable to their control counterparts. Female PAE mice that received either reinforcer types did not exhibit any deficits on behavioral flexibility. Female saccharine control mice that received liquid, but not pellet, rewards showed increased perseverative responding during the early reversal phase.DiscussionThese data suggest that reinforcer type can have a major impact on motivation, and therefore performance, during reversal learning. Highly motivating rewards may mask behavioral deficits seen with more moderately sought rewards and gestational exposure to the non-caloric sweetener, saccharine, can impact behavior motivated by those reinforcers in a sex-dependent manner.

Covid-19-related social-distancing measures have dramatically limited physical social contact between individuals and increased monetary and health concerns for individuals of all ages. We wondered how these new societal conditions would impact the choices individuals make about monetary, health, and social rewards, and if these unprecedented conditions would have a differential impact on older individuals. We conducted two online studies to examine temporal discounting of monetary, health, and social rewards; stated preferences for monetary, health, and social rewards; and physical distancing behaviors. Both studies recruited equal numbers of White/Caucasian, Black/African American, and Hispanic/Latinx participants. We found that older adults were more likely to prefer smaller, sooner social and health-related rewards in decision-making tasks. These data further support the assertion that older adults have increased motivation for social and health rewards compared to younger individuals and that these age differences in motivation are important to consider when examining decision-making across the adult life span. [ABSTRACT FROM AUTHOR]

Music has marked its presence since the evolution of human society and has occupied our day-to-day life. It has also contributed in forming society and civilizations. Advancement in technology and portability of multimedia devices have made the access to music a common norm. It has various purposes like social cohesion, emotional expressions, interpersonal communication, recreation. It has a great bonding power and is important in terms of social dynamics. As it has an effect on society, so does it have an effect on an individual’s mind and body as well. Music intervention is convenient, inexpensive, user controlled and seems to be influencing the physiological system in a positive way if rightly used, this therapy and its intervention is applied now-a-days in various ailments and disease states as an adjuvant therapy. Vast research is going on to find the right music that could have the desired therapeutic effect where the physiology is deranged from the normal. Effect of music on pain modulation, exercise performance, Cardiac and Autonomic functions, Heart rate variability, emotions, anxiety, stress and entrainment of biological rhythms are well evaluated. Its application in enhancing higher functions like memory tasks and learning are also known. The evident physiological implications of music on various physiological parameters are being elaborated.

Mindfulness training (MT) has been shown to influence smoking behavior, yet the involvement of reinforcement learning processes as underlying mechanisms remains unclear. This naturalistic, single-arm study aimed to examine slope trajectories of smoking behavior across uses of our app-based MT craving tool for smoking cessation, and whether this relationship would be mediated by the attenuating impact of MT on expected reward values of smoking. Our craving tool embedded in our MT app-based smoking cessation program was used by 108 participants upon the experience of cigarette cravings in real-world contexts. Each use of the tool involved mindful awareness to the experience of cigarette craving, a decision as to whether the participant wanted to smoke or ride out their craving with a mindfulness exercise, and paying mindful attention to the choice behavior and its outcome (contentment levels felt from engaging in the behavior). Expected reward values were computed using contentment levels experienced from the choice behavior as the reward signal in a Rescorla–Wagner reinforcement learning model. Multi-level mediation analysis revealed a significant decreasing trajectory of smoking frequency across MT craving tool uses and that this relationship was mediated by the negative relationship between MT and expected reward values (all ps < 0.001). After controlling for the mediator, the predictive relationship between MT and smoking was no longer significant (p < 0.001 before and p = 0.357 after controlling for the mediator). Results indicate that the use of our app-based MT craving tool is associated with negative slope trajectories of smoking behavior across uses, mediated by reward learning mechanisms. This single-arm naturalistic study provides preliminary support for further RCT studies examining the involvement of reward learning mechanisms underlying app-based mindfulness training for smoking cessation. [ABSTRACT FROM AUTHOR]

Growing evidence suggests that humans and other animals assign value to a stimulus based not only on its inherent rewarding properties, but also on the costs of the action required to obtain it, such as the cost of time. Here, we examined whether such cost also occurs for mentally simulated actions. Healthy volunteers indicated their subjective value for snack foods while the time to imagine performing the action to obtain the different stimuli was manipulated. In each trial, the picture of one food item and a home position connected through a path were displayed on a computer screen. The path could be either large or thin. Participants first rated the stimulus, and then imagined moving the mouse cursor along the path from the starting position to the food location. They reported the onset and offset of the imagined movements with a button press. Two main results emerged. First, imagery times were significantly longer for the thin than the large path. Second, participants liked significantly less the snack foods associated with the thin path (i.e., with longer imagery time), possibly because the passage of time strictly associated with action imagery discounts the value of the reward. Importantly, such effects were absent in a control group of participants who performed an identical valuation task, except that no action imagery was required. Our findings hint at the idea that imagined actions, like real actions, carry a cost that affects deeply how people assign value to the stimuli in their environment. [ABSTRACT FROM AUTHOR]

The present study investigated whether the representation of subjective preferences in the event-related potential is manipulable through selective devaluation, i.e., the consumption of a specific food item until satiety. Thirty-four participants completed a gambling task in which they chose between virtual doors to find one of three snack items, representing a high, medium, or low preference outcome as defined by individual desire-to-eat ratings. In one of two test sessions, they underwent selective devaluation of the high preference outcome. In the other, they completed the task on an empty stomach. Consistent with previous findings, averaged across sessions, amplitudes were increased for more preferred rewards in the time windows of P2, late FRN, and P300. As hypothesised, we also found a selective devaluation effect for the high preference outcome in the P300 time window, reflected in a decrease in amplitude. The present results provide evidence for modulations of reward processing not only by individual factors, such as subjective preferences, but also by the current motivational state. Importantly, the present data suggest that selective devaluation effects in the P300 may be a promising tool to further characterise altered valuation of food rewards in the context of eating disorders and obesity. [ABSTRACT FROM AUTHOR]

Unequal outcomes disrupt cooperation in some situations, but this has not been tested in the context of coordination in economic games. To explore this, we tested brown capuchins (Sapajus [Cebus] apella) on a manual version of the Stag Hunt (or Assurance) Game, in which individuals sequentially chose between two options, Stag or Hare, and were rewarded according to their choices and that of their partner. Typically, coordination on Stag results in an equal highest payout, whereas coordinating on Hare results in a guaranteed equal but lower payoff and uncoordinated play results in the lowest payoff when playing Stag. We varied this structure such that one capuchin received double the rewards for the coordinated Stag outcome; thus, it was still both animals' best option, but no longer equally rewarding. Despite the inequality, capuchins coordinated on Stag in 78% of trials, and neither payoff structure nor their partner's choice impacted their decision. Additionally, there was no relationship between self‐scratching, a measure of stress in capuchins, and choices. After completing the study, we discovered our reward, cheerios, was sufficiently valuable that in another study, capuchins never refused it, so post hoc we repeated the study using a lower value reward, banana flavored pellets. Capuchins completed only 26% of the pellet trials (compared to 98% with cheerios), constraining our ability to interpret the results, but nonetheless the monkeys showed a decrease in preference for Stag, particularly when they received fewer rewards for the coordinated Stag outcome. These results reinforce capuchins' ability to find coordinated outcomes in the Stag Hunt game, but more work is needed to determine whether the monkeys did not mind the inequality or were unwilling to sacrifice a highly preferred food to rectify it. In either case, researchers should carefully consider the impact of their chosen rewards on subjects' choices. Research Highlights: −Capuchins coordinate and respond negatively to inequity.−We tested coordination when one monkey got a greater reward for doing so.−They consistently coordinated, but only for preferred rewards, highlighting the importance of reward value in such tasks. [ABSTRACT FROM AUTHOR]

Background and aims: Maladaptive eating habits are a major cause of obesity and weight-related illness. The development of empirically-based approaches, such as mindfulness training (MT) that target accurate mechanisms of action to address these behaviors is therefore critical. Two studies were conducted to examine the impact of MT on maladaptive eating and determine the involvement of reinforcement learning mechanisms underlying these effects. Methods: In Study1, maladaptive eating behaviors were assessed using self-report questionnaires at baseline and 8 weeks after an app-based MT intervention (n 5 46). A novel mindful eating craving tool was embedded in our intervention to assess: eating behaviors (intake frequency/magnitude), and reward (contentment ratings) experienced after eating. Using a wellestablished reinforcement learning (Rescorla-Wagner) model, expected reward values (EV) were estimated as a function of contentment levels reported after eating. In Study2 (n 5 1,119), craving tool assessments were examined in an independent sample using the app in a real-world naturalistic context. Results: Study 1’s results revealed a significant decrease in EV and eating behaviors across craving tool uses. In addition, changes in reward values predicted decreases in eating behaviors. Finally, Study 1’s results revealed significant pre-post intervention reductions in self-reported eating behaviors. In Study2, we observed a significant decrease in EV, but not in eating behaviors, across craving tool uses. Study 2 also revealed a predictive relationship between EV and eating behaviors. Discussion and conclusions: These results support the implementation of MT to prevent and treat maladaptive eating behaviors, which target reinforcement learning processes as mechanisms of action. [ABSTRACT FROM AUTHOR]

Goal-directed behavior is influenced by both reward value as well as internal state. A large body of research has focused on how reward value and internal drives such as hunger influence motivation in rodent models, however less work has focused on how these factors may differentially affect impulsivity. In these studies, we tested the effect of internal drive versus reward value on different facets of reward-related behavior including impulsive action, impulsive choice and, motivation. We varied reward value by changing the concentration of sucrose in the reward outcome, and varied internal drive by manipulating thirst through water restriction. Consistent with the literature we found that both internal state and reward value influenced motivation. However, we found that in high effort paradigms, only internal state influenced motivation with minimal effects of reward value. Interestingly, we found that internal state and reward value differentially influence different subtypes of impulsivity. Internal state, and to a lesser extent, reward value, influenced impulsive action as measured by premature responding. On the other hand, there were minimal effects of either reward value or homeostatic state on impulsive choice as measured by delay discounting. Overall, these studies begin to address how internal state and reward value differentially drive impulsive behavior. Understanding how these factors influence impulsivity is important for developing behavioral interventions and treatment targets for patients with dysregulated motivated or impulsive behavior. • External reward value and internal state are both drives to motivate goal directed behavior. • Both of these factors influence motivation, however internal homeostatic drive dominates under high effort requirements. • Decreasing internal drive decreases impulsive action more than decreasing external reward value. • Neither factor differentially influences impulsive choice measured in a delay discounting paradigm. [ABSTRACT FROM AUTHOR]

Brain regions associated with the processing of tangible rewards (such as money, food, or sex) are also involved in anticipating social rewards and avoiding social punishment. To date, studies investigating the neural underpinnings of social reward have presented feedback via static or dynamic displays of faces to participants. However, research demonstrates that participants find another type of social stimulus, namely, biological motion, rewarding as well, and exert effort to engage with this type of stimulus. Here we examine whether feedback presented via body gestures in the absence of facial cues also acts as a rewarding stimulus and recruits reward-related brain regions. To achieve this, we investigated the neural underpinnings of anticipating social reward and avoiding social disapproval presented via gestures alone, using a social incentive delay task. As predicted, the anticipation of social reward and avoidance of social disapproval engaged reward-related brain regions, including the nucleus accumbens, in a manner similar to previous studies’ reports of feedback presented via faces and money. This study provides the first evidence that human body motion alone engages brain regions associated with reward processing in a similar manner to other social (i.e. faces) and non-social (i.e. money) rewards. The findings advance our understanding of social motivation in human perception and behavior.

Two systems in the brain that are involved in emotional and economic decision-making are described. The first is an evolutionarily old emotion-based system that operates on rewards defined by the genes such as food, warmth, social reputation, and having children. Such decisions are often based on heuristics, such as being highly sensitive to losses, because a single loss might influence one's reproductive success. This is a multidimensional system with many rewards and punishers, all of which cannot be simultaneously optimized. The second route to decision-making involves reasoning, in which it is assumed that utility can be accurately assessed and logical reason can be applied, though the human brain is not naturally computationally good at logical assessment. When decisions are taken, all those factors apply, and in addition there is noise introduced into the system by the random firing times of neurons for a given mean firing rate. The implications for economic decision-making are described. In macroeconomics, it is assumed that the economy behaves like one “representative” agent who can take rational and logical decisions, and who can maximize utility over a constraint. Given the neuroscience of decision-making, the situation is more complex. The utility function may be multidimensional, the reward value along each dimension may fluctuate, the reasoning may be imperfect, and the decision-making process is subject to noise in the brain, making it somewhat random from occasion to occasion. Moreover, each individual has a different set of value functions along each dimension, with different sensitivities to different rewards and punishers, which are expressed in the different personalities of different individuals. These factors underlying the neuroscience of human decision-making need to be taken into account in building and utilizing macroeconomic theories.

To study how effort affects reward value, we replicated Fortes, Vasconcelos and Machado's (2015) study using an adjusting‐delay task. Nine pigeons chose between a standard alternative that gave access to 4 s of food, after a 10 s delay, and an adjusting‐delay alternative that gave access to 12 s of food after a delay that changed dynamically with the pigeons' choices, decreasing when they preferred the standard alternative, and increasing when they preferred the adjusting alternative. The delay value at which preference stabilized defined the indifference point, a measure of reward value. To manipulate effort across phases, we varied the response rate required during the delay of the standard alternative. Results showed that a) the indifference point increased in the higher‐response‐rate phases, suggesting that reward value decreased with effort, and b) in the higher‐response‐rate phases, response rate in the standard alternative was linearly related to the indifference point. We advance several conceptions of how effort may change perceived delay or amount and thereby affect reward value. [ABSTRACT FROM AUTHOR]

• Reward value influences memory. • We manipulate value while equating task-usefulness. • Value did not exert a large influence on free recall probability. • Value did influence recall order and lexical judgements. • High-value words were recalled earlier and responded faster. A common finding is that items associated with higher reward value are subsequently remembered better than items associated with lower value. A confounding factor is that when a higher value stimuli is presented, this typically signals to participants that it is now a particularly important time to engage in the task. When this was controlled, Madan, Fujiwara, Gerson, and Caplan (2012) still found a large value-bias of memory. Their value-learning procedure, however, explicitly pitted high- against low-value words. Our novel value-learning procedure trained words one at a time, avoiding direct competition between words, but with no difference in words signalling participants to engage in the task. Results converged on null effects of value on subsequent free recall accuracy. Re-analyses attributed Madan et al.'s value-bias to competition between choice items that were paired during learning. Value may not bias memory if it does not signal task importance or induce inter-item competition. [ABSTRACT FROM AUTHOR]

A prominent target of the basal ganglia is the superior colliculus (SC) which controls gaze orientation (saccadic eye movement in primates) to an important object. This 'object choice' is crucial for choosing an action on the object. SC is innervated by the substantia nigra pars reticulata (SNr) which is controlled mainly by the caudate nucleus (CD). This CD‐SNr‐SC circuit is sensitive to the values of individual objects and facilitates saccades to good objects. The object values are processed differently in two parallel circuits: flexibly by the caudate head (CDh) and stably by the caudate tail (CDt). To choose good objects, we need to reject bad objects. In fact, these contrasting functions are accomplished by the circuit originating from CDt: The direct pathway focuses on good objects and facilitates saccades to them; the indirect pathway focuses on bad objects and suppresses saccades to them. Inactivation of CDt deteriorated the object choice, because saccades to bad objects were no longer suppressed. This suggests that the indirect pathway is important for object choice. However, the direct and indirect pathways for 'object choice', which aim at the same action (i.e., saccade), may not work for 'action choice'. One possibility is that circuits controlling different actions are connected through the indirect pathway. Additional connections of the indirect pathway with brain areas outside the basal ganglia may also provide a wider range of behavioral choice. In conclusion, basal ganglia circuits are composed of the basic direct/indirect pathways and additional connections and thus have acquired multiple functions. Parallel circuits from the caudate nucleus to the superior colliculus choose objects by their values, but selectively: anterior circuit using flexible values, posterior circuit using stable values. In the posterior circuit, the object choice is made by saccading to good objects (by direct pathway) and saccading away from bad objects (by indirect pathway). In contrast, action choice may require interactions among multiple basal ganglia circuits, especially through indirect pathways, according to our hypothesis. [ABSTRACT FROM AUTHOR]

Spatial co-location pattern mining is employed to identify a group of spatial types whose instances are frequently located in spatial proximity. Current co-location mining methods have two limitations: (1) it is difficult to set an appropriate proximity threshold to identify close instances in an unknown region, and (2) such methods neglect the effects of the distance values between instances and long-distance instance effects on pattern significance. This paper proposes a novel maximal co-location algorithm to address these problems. To remove the first constraint, the algorithm uses Voronoi diagrams to extract the most related instance pairs of different types and their normalized distances, from which two distance-separating parameters are adaptively extracted using a statistical method. To remove the second constraint, the algorithm employs a reward-based verification based on distance-separating parameters to identify the prevalent patterns. Our experiments with both synthetic data and real data from Beijing, China, demonstrate that the algorithm can identify many interesting patterns that are neglected by traditional co-location methods. [ABSTRACT FROM AUTHOR]

The use of relevant reinforcers during treatment is essential for successful interventions. This especially applies to forensic psychiatric populations, which are known to be resistant to treatment. However, it is not clear which rewards are of importance for different types of forensic patients. The aim of the present study was to investigate reward preferences in two forensic patient populations. Applying the concept mapping methodology, 34 male incarcerated violent offenders under imposed psychiatric treatment and 41 male forensic outpatients generated, prioritized and categorized 98 and 115 rewards, respectively. Multidimensional scaling and hierarchical cluster analyses resulted in two concept maps with eight (inpatients) and five (outpatients) reward categories. In both maps, one dimension represented the effort required to achieve the rewards. The other dimension represented either the rewards' independency of the clinical environment (inpatients) or the level of arousal associated with the rewards (outpatients). Both inpatients and outpatients tended to rate high-effort rewards as the most valuable, especially when the rewards involved the clinical environment of the patient or when rewards were associated with lower levels of arousal. The results highlight the importance of considering individual differences in reward preferences in the development of therapeutic interventions. [ABSTRACT FROM AUTHOR]

This paper honors the contributions made by Anthony (Tony) Sclafani and Karen Ackroff to both the Columbia University Seminar on Appetitive Behavior and to the field of ingestive behavior in general. We review their use of the progressive ratio (PR) licking paradigm, to determine whether the taste of sucrose, independent of its post-ingestive effects, is always positively reinforcing in animals. They demonstrated a monotonic increase in licking as concentration increased, and obtained results identical to those obtained with a lever-pressing paradigm, but licking was easier and more natural than lever pressing. The PR paradigm was translated to evaluate liquid food reward value in humans. An instrument (the sipometer) was devised that initially permitted a few seconds access to small amounts of a sweet beverage as the participants increased the time to obtain it in 3-5-sec increments. The device went through two refinements and currently delivers the reinforcer and measures the pressure exerted to obtain it. The sipometer is compared with other techniques for measuring motivation and reward. The use of the sipometer and the PR method are discussed in relation to the theoretical challenges inherent in measuring motivation and pleasure, from both psychological and behavioral economics perspectives, and why it is or is not important to separate these processes for both theoretical and practical applications. [ABSTRACT FROM AUTHOR]

Reward processing, which plays a critical role in adaptive behavior, is impaired in addiction disorders, which are accompanied by functional abnormalities in brain reward circuits. Internet gaming disorder, like substance addiction, is thought to be associated with impaired reward processing, but little is known about how it affects learning, especially when feedback is conveyed by less-salient motivational events. Here, using both monetary (±500 KRW) and symbolic (Chinese characters “right” or “wrong”) rewards and penalties, we investigated whether behavioral performance and feedback-related neural responses are altered in Internet game overuse (IGO) group. Using functional MRI, brain responses for these two types of reward/penalty feedback were compared between young males with problems of IGO (IGOs, n = 18, mean age = 22.2 ± 2.0 years) and age-matched control subjects (Controls, n = 20, mean age = 21.2 ± 2.1) during a visuomotor association task where associations were learned between English letters and one of four responses. No group difference was found in adjustment of error responses following the penalty or in brain responses to penalty, for either monetary or symbolic penalties. The IGO individuals, however, were more likely to fail to choose the response previously reinforced by symbolic (but not monetary) reward. A whole brain two-way ANOVA analysis for reward revealed reduced activations in the IGO group in the rostral anterior cingulate cortex/ventromedial prefrontal cortex (vmPFC) in response to both reward types, suggesting impaired reward processing. However, the responses to reward in the inferior parietal region and medial orbitofrontal cortex/vmPFC were affected by the types of reward in the IGO group. Unlike the control group, in the IGO group the reward response was reduced only for symbolic reward, suggesting lower attentional and value processing specific to symbolic reward. Furthermore, the more severe the Internet gaming overuse symptoms in the IGO group, the greater the activations of the ventral striatum for monetary relative to symbolic reward. These findings suggest that IGO is associated with bias toward motivationally salient reward, which would lead to poor goal-directed behavior in everyday life.

The Social Motivation Theory posits that a reduced sensitivity to the value of social stimuli, specifically faces, can account for social impairments in Autism Spectrum Disorders (ASD). Research has demonstrated that typically developing (TD) individuals preferentially orient towards another type of salient social stimulus, namely biological motion. Individuals with ASD, however, do not show this preference. While the reward value of faces to both TD and ASD individuals has been well-established, the extent to which individuals from these populations also find human motion to be rewarding remains poorly understood. The present study investigated the value assigned to biological motion by TD participants in an effort task, and further examined whether these values differed among individuals with more autistic traits. The results suggest that TD participants value natural human motion more than rigid, machine-like motion or non-human control motion, but this preference is attenuated among individuals reporting more autistic traits. This study provides the first evidence to suggest that individuals with more autistic traits find a broader conceptualisation of social stimuli less rewarding compared to individuals with fewer autistic traits. By quantifying the social reward value of human motion, the present findings contribute an important piece to our understanding of social motivation in individuals with and without social impairments. [ABSTRACT FROM AUTHOR]

A previous study revealed that, although monkeys with bilateral lesions of either the orbitofrontal cortex (OFC) or the amygdala could learn an action--outcome task, they could not adapt their choices in response to devalued outcomes. Specifically, they could not adjust their choice between two actions after the value of the outcome associated with one of the actions had decreased. Here, we investigated whether OFC needs to interact functionally with the amygdala in mediating such choices. Rhesus monkeys were trained to make two mutually exclusive actions on a touch-sensitive screen: "tap" and "hold." Taps led to the availability of one kind of food outcome; holds produced a different food. On each trial, monkeys could choose either a tap or a hold to earn the corresponding food reward. After consuming one of the two foods to satiety, monkeys were then tested on their ability to adapt their choices in response to the updated relative valuation of the two predicted outcomes. Whereas intact (control) monkeys shifted their choices toward the action associated with the higher value (nonsated) food, monkeys with crossed surgical disconnection of the amygdala and OFC did not. These findings demonstrate that amygdala-OFC interactions are necessary for choices among actions based on the updated value of predicted outcomes and they also have a bearing on the idea that OFC specializes in stimulus- or object-based choices in contrast to action- or response-based choices. [ABSTRACT FROM AUTHOR]

Rats retain source memory (memory for the origin of information) over a retention interval of at least 1 week, whereas their spatial working memory (radial maze locations) decays within approximately 1 day. We have argued that different forgetting functions dissociate memory systems. However, the two tasks, in our previous work, used different reward values. The source memory task used multiple pellets of a preferred food flavor (chocolate), whereas the spatial working memory task provided access to a single pellet of standard chow-flavored food at each location. Thus, according to the reward-value hypothesis, enhanced performance in the source memory task stems from enhanced encoding/memory of a preferred reward. We tested the reward-value hypothesis by using a standard 8-arm radial maze task to compare spatial working memory accuracy of rats rewarded with either multiple chocolate or chow pellets at each location using a between-subjects design. The reward-value hypothesis predicts superior accuracy for high-valued rewards. We documented equivalent spatial memory accuracy for high- and low-value rewards. Importantly, a 24-h retention interval produced equivalent spatial working memory accuracy for both flavors. These data are inconsistent with the reward-value hypothesis and suggest that reward value does not explain our earlier findings that source memory survives unusually long retention intervals. [ABSTRACT FROM AUTHOR]

In a complex and uncertain world, how do we select appropriate behavior? One possibility is that we choose actions that are highly reinforced by their probabilistic consequences (model-free processing). However, we may instead plan actions prior to their actual execution by predicting their consequences (model-based processing). It has been suggested that the brain contains multiple yet distinct systems involved in reward prediction. Several studies have tried to allocate model-free and model-based systems to the striatum and the lateral prefrontal cortex (LPFC), respectively. Although there is much support for this hypothesis, recent research has revealed discrepancies. To understand the nature of the reward prediction systems in the LPFC and the striatum, a series of single-unit recording experiments were conducted. LPFC neurons were found to infer the reward associated with the stimuli even when the monkeys had not yet learned the stimulus-reward associations directly. Striatal neurons seemed to predict the reward for each stimulus only after directly experiencing the stimulus-reward contingency. However, the one exception was Exclusive Or situations in which striatal neurons could predict the reward without direct experience. Previous single-unit studies in monkeys have reported that neurons in the LPFC encode category information, and represent reward information specific to a group of stimuli. Here, as an extension of these, we review recent evidence that a group of LPFC neurons can predict reward specific to a category of visual stimuli defined by relevant behavioral responses. We suggest that the functional difference in reward prediction between the LPFC and the striatum is that while LPFC neurons can utilize abstract code, striatal neurons can code individual associations between stimuli and reward but cannot utilize abstract code.