Fins, feathers, fingers, and finding an explanation for the puzzle of ephemeral rewards.

This article discusses the ephemeral reward task and how it is not always a clear and concise choice. This is demonstrated through some animal studies involving birds and primates. This article also shows that when compared to human studies, that there are positive correlations between the BART and optimal choice in the ephemeral reward task, meaning that those who took more risks also were more inclined to be optimal. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Daily use of self-leadership strategies and employee work engagement while working from home and the office.

Employees' work engagement may vary by work location (office vs. home office), assuming that working at home requires greater self-regulation. Hence, self-leadership may play an important role when employees work at home. The present study investigates whether employees use self-leadership strategies (self-goal setting, self-reward, self-punishment, self-cueing, and visualization of successful performance) more often on home days than on office days. We also examine how these strategies are related to daily work engagement, and whether they are more effective for promoting work engagement depending on the work location. One hundred and one employees completed daily questionnaires on office and home days, resulting in 514 observations. Multilevel analyses revealed that employees reported higher use of self-goal setting, self-reward, and visualization on home days than on office days. Furthermore, we found that applying these strategies was positively related to day-specific work engagement. Nevertheless, self-cueing had no effect and self-punishment was detrimental to work engagement. Moreover, we found no support for the idea that the effectiveness of self-leadership strategies for promoting work engagement depends on the work location. These findings contribute to our understanding of self-leadership strategies promoting work engagement on home and office days.

Modulation of High-Frequency rTMS on Reward Circuitry in Individuals with Nicotine Dependence: A Preliminary fMRI Study.

Although previous studies have shown that repetitive transcranial magnetic stimulation (rTMS) can ameliorate addictive behaviors and cravings, the underlying neural mechanisms remain unclear. This study aimed to investigate the effect of high-frequency rTMS with the left dorsolateral prefrontal cortex (L-DLPFC) as a target region on smoking addiction in nicotine-dependent individuals by detecting the change of spontaneous brain activity in the reward circuitry. We recruited 17 nicotine-dependence participants, who completed 10 sessions of 10 Hz rTMS over a 2-week period and underwent evaluation of several dependence-related scales, and resting-state fMRI scan before and after the treatment. Functional connectivity (FC) analysis was conducted with reward-related brain regions as seeds, including ventral tegmental area, bilateral nucleus accumbens (NAc), bilateral DLPFC, and bilateral amygdala. We found that, after the treatment, individuals showed reduced nicotine dependence, alleviated tobacco withdrawal symptoms, and diminished smoking cravings. The right NAc showed increased FC with right fusiform gyrus, inferior temporal gyrus (ITG), calcarine fissure and surrounding cortex, superior occipital gyrus (SOG), lingual gyrus, and bilateral cuneus. No significant FC changes were observed in other seed regions. Moreover, the changes in FC between the right NAc and the right ITG as well as SOG before and after rTMS were negatively correlated with changes in smoking scale scores. Our findings suggest that high-frequency L-DLPFC-rTMS reduces nicotine dependence and improves tobacco withdrawal symptoms, and the dysfunctional connectivity in reward circuitry may be the underlying neural mechanism for nicotine addiction and its therapeutic target.

Which Concepts Are Key to Transitioning From Nonhuman Animal Models to Engineered Microphysiological Systems in Biomedical Research?

A transition from nonhuman animal models to engineered microphysiological systems (MPS), such as organoids and organ-on-a-chip technologies, would signal a paradigm shift in biomedical research. Despite MPS' potential to more accurately model human physiology, reduce high failure rates of drugs in clinical trials, and limit unnecessary animal use, widespread adoption is hampered by public opinion and lack of scalability, standardization, and current regulatory uptake. This article suggests how 5 key concepts (awareness, access, education, application, and rewards) could help address these barriers. These concepts are part of a framework that underscores a need to integrate MPS into mainstream biomedical research and to better promote ethical responsibility for the means of biomedical innovation.

Understanding the relationships among adolescents' internet dependence, reward, cognitive control processing, and learning burnout: a network perspective in China.

Alterations in the reward and cognitive control systems are commonly observed among adolescents with internet dependence (ID), and this impairment is often accompanied by social dysfunctions, such as academic burnout. However, the intercorrelations among ID, reward, cognitive control processing, and learning burnout remain unclear. We recruited 1074 Chinese adolescents to investigate the complex interrelationships among these variables using network analysis. The resulting network revealed patterns that connected ID to the behavioral inhibition/activation system (BIS/BAS), self-control, and learning burnout; these results exhibited reasonable stability and test-retest consistency. Throughout the network, the node of BAS-drive was the critical influencing factor, and the node of self-control was the protection factor. In addition, several symptoms of learning burnout and ID were positively associated with sensitivity to punishment. As revealed by the network comparison test, the network constructed among internet dependent (ID) group differed from the network constructed among internet nondependent (IND) group not only in the edges between BIS and learning burnout but also in terms of the edges associated with learning burnout. In conclusion, this study provides insights into the complex mechanisms underlying ID among adolescents from the perspective of the network relationships between core influencing factors and negative consequences. It validates the dual-system model of risky behavior among adolescents and offers a foundation for early warning and interventions for ID in this context.

Dogs with prior experience of a task still overimitate their caregiver.

Domestic dogs have been shown to copy their caregiver's actions, including ones which are causally-irrelevant to a physical goal-a behaviour called "overimitation". In a new overimitation task with a non-food reward, this study investigated "causal misunderstanding"-falsely assuming causally-irrelevant actions to have functional relevancy-as an explanation for dog overimitation (N = 81). By providing dogs with prior experience of the task to learn about the consequences of its irrelevant box-stepping and relevant bucket-opening action to obtain a toy-ball, we tested whether and when dogs would copy their caregiver's irrelevant-action demonstrations. Dogs with and without prior experience were compared to a third (control) group of dogs, who had neither prior experience nor caregiver demonstrations of the task. Results revealed that the timing of overimitation, rather than its frequency, was closely related to dogs' prior experience: dogs with prior experience attended to their reward first, then interacted with the irrelevant box later ("post-goal overimitation"), while dogs without prior experience first interacted with the irrelevant box ("pre-goal overimitation"). Our results suggest that, when action consequences are understood, dogs are overimitating for a secondary social goal that is clearly distinct from the task goal of obtaining a physical reward.

Network state changes in sensory thalamus represent learned outcomes.

Thalamic brain areas play an important role in adaptive behaviors. Nevertheless, the population dynamics of thalamic relays during learning across sensory modalities remain unknown. Using a cross-modal sensory reward-associative learning paradigm combined with deep brain two-photon calcium imaging of large populations of auditory thalamus (medial geniculate body, MGB) neurons in male mice, we identified that MGB neurons are biased towards reward predictors independent of modality. Additionally, functional classes of MGB neurons aligned with distinct task periods and behavioral outcomes, both dependent and independent of sensory modality. During non-sensory delay periods, MGB ensembles developed coherent neuronal representation as well as distinct co-activity network states reflecting predicted task outcome. These results demonstrate flexible cross-modal ensemble coding in auditory thalamus during adaptive learning and highlight its importance in brain-wide cross-modal computations during complex behavior.

Insights into the interaction between time and reward prediction on the activity of striatal tonically active neurons: A pilot study in rhesus monkeys.

Prior studies have documented the role of the striatum and its dopaminergic input in time processing, but the contribution of local striatal cholinergic innervation has not been specifically investigated. To address this issue, we recorded the activity of tonically active neurons (TANs), thought to be cholinergic interneurons in the striatum, in two male macaques performing self-initiated movements after specified intervals in the seconds range have elapsed. The behavioral data showed that movement timing was adjusted according to the temporal requirements. About one-third of all recorded TANs displayed brief depressions in firing in response to the cue that indicates the interval duration, and the strength of these modulations was, in some instances, related to the timing of movement. The rewarding outcome of actions also impacted TAN activity, as reflected by stronger responses to the cue paralleled by weaker responses to reward when monkeys performed correctly timed movements over consecutive trials. It therefore appears that TAN responses may act as a start signal for keeping track of time and reward prediction could be incorporated in this signaling function. We conclude that the role of the striatal cholinergic TAN system in time processing is embedded in predicting rewarding outcomes during timing behavior.

On the effects of impulsivity and compulsivity on neural correlates of model-based performance.

Impaired goal-directed behavior is associated with a range of mental disorders, implicating underlying transdiagnostic factors. While compulsivity has been linked to reduced model-based (MB) control, impulsivity has rarely been studied in the context of reinforcement learning despite its links to reward processing and cognitive control. This study investigated the neural mechanisms underlying MB control and the influence of impulsivity and compulsivity, using EEG data from 238 individuals during a two-step decision making task. Single-trial analyses revealed a modulation of the feedback-related negativity (FRN), where amplitudes were higher after common transitions and positive reward prediction error (RPE), indicating a valence effect. Meanwhile, enhanced P3 amplitudes after rare transitions and both positive and negative RPE possibly reflect surprise. In a second step, we regressed the mean b values of the effect of RPE on the EEG signals onto self-reported impulsivity and compulsivity and behavioral MB control (w). The effect of RPE on FRN-related activity was mainly associated with higher w scores, linking the FRN to MB control. Crucially, the modulation of the P3 by RPE was negatively associated with compulsivity, pointing to a deficient mental model in highly compulsive individuals.

Within-session chasing of losses and wins in an online eCasino.

Chasing refers to the escalation of betting behaviour. It is conventionally seen when losing but can also be seen after wins. Diagnostic and screening items for gambling problems describe chasing as returning 'another day' to gamble. However, gamblers may also chase within sessions, and this is particularly relevant in online gambling. This study focused on two expressions of within-session chasing: (1) increasing the bet amount, or (2) a reduced probability of quitting the session, as a function of prior losses or wins. These expressions were examined across five online gambling products: slot machines, probability games, blackjack, video poker, and roulette. Our results showed that gamblers bet more and played longer sessions after immediate losses, but they bet less and played shorter sessions when losing cumulatively. The reversed pattern in the cumulative model may be due to financial constraints. For wins, gamblers bet more after both immediate and cumulative wins, but they also played shorter sessions. Chasing patterns were qualitatively similar by game type-with limited evidence for our hypothesis that chasing would be greatest for slot machines as an established high-risk category. Overall, chasing is multi-faceted, varying across the behavioural expressions, by the immediate or cumulative timeframe of prior outcomes, and by game type.

Learning depends on the information conveyed by temporal relationships between events and is reflected in the dopamine response to cues.

Contemporary theories guiding the search for neural mechanisms of learning and memory assume that associative learning results from the temporal pairing of cues and reinforcers resulting in coincident activation of associated neurons, strengthening their synaptic connection. While enduring, this framework has limitations: Temporal pairing-based models of learning do not fit with many experimental observations and cannot be used to make quantitative predictions about behavior. Here, we present behavioral data that support an alternative, information-theoretic conception: The amount of information that cues provide about the timing of reward delivery predicts behavior. Furthermore, this approach accounts for the rate and depth of both inhibitory and excitatory learning across paradigms and species. We also show that dopamine release in the ventral striatum reflects cue-predicted changes in reinforcement rates consistent with subjects understanding temporal relationships between task events. Our results reshape the conceptual and biological framework for understanding associative learning.

Orphan receptor-GPR52 inverse agonist efficacy in ameliorating chronic stress-related deficits in reward motivation and phasic accumbal dopamine activity in mice.

Reward processing dysfunctions e.g., anhedonia, apathy, are common in stress-related neuropsychiatric disorders including depression and schizophrenia, and there are currently no established therapies. One potential therapeutic approach is restoration of reward anticipation during appetitive behavior, deficits in which co-occur with attenuated nucleus accumbens (NAc) activity, possibly due to NAc inhibition of mesolimbic dopamine (DA) signaling. Targeting NAc regulation of ventral tegmental area (VTA) DA neuron responsiveness to reward cues could involve either the direct or indirect-via ventral pallidium (VP)-pathways. One candidate is the orphan G protein-coupled receptor GPR52, expressed by DA receptor 2 NAc neurons that project to VP. In mouse brain-slice preparations, GPR52 inverse agonist (GPR52-IA) attenuated evoked inhibitory postsynaptic currents at NAc-VP neurons, which could disinhibit VTA DA neurons. A mouse model in which chronic social stress leads to reduced reward learning and effortful motivation was applied to investigate GPR52-IA behavioral effects. Control and chronically stressed mice underwent a discriminative learning test of tone-appetitive behavior-sucrose reinforcement: stress reduced appetitive responding and discriminative learning, and these anticipatory behaviors were dose-dependently reinstated by GPR52-IA. The same mice then underwent an effortful motivation test of operant behavior-tone-sucrose reinforcement: stress reduced effortful motivation and GPR52-IA dose-dependently restored it. In a new cohort, GRABDA-sensor fibre photometry was used to measure NAc DA activity during the motivation test: in stressed mice, reduced motivation co-occurred with attenuated NAc DA activity specifically to the tone that signaled reinforcement of effortful behavior, and GPR52-IA ameliorated both deficits. These findings: (1) Demonstrate preclinical efficacy of GPR52 inverse agonism for stress-related deficits in reward anticipation during appetitive behavior. (2) Suggest that GPR52-dependent disinhibition of the NAc-VP-VTA-NAc circuit, leading to increased phasic NAc DA signaling of earned incentive stimuli, could account for these clinically relevant effects.

The lateral septum returns to the center stage of brain reward.

In this issue of Neuron, Chen et al.1 found that lateral septum Esr1-expressing cells respond to both non-drug and drug rewards. Mice will lever press for optogenetic stimulation of these neurons, which are also critical to methamphetamine locomotor sensitization, conditioned place preference, self-administration, and reinstatement.

Monetary reward enhances response inhibition processes manifested in No-go P3.

This study investigated the impact of motivational valence on No-go P3 and N2 by incorporating monetary rewards based on response outcomes. We also investigated how personality differences in terms of the behavioral inhibition system (BIS) and behavioral approach system (BAS) influenced No-go N2 and No-go P3. Twenty-eight participants performed Go/No-go tasks (80 % Go and 20 % No-go) under two conditions. In the reward condition, each correct-rejection trial for the No-go stimulus was rewarded with 10 yen (∼6 cents), whereas in the neutral condition, neither monetary rewards nor punishments were contingent on response outcomes. Individual responsiveness to punishment and rewards was evaluated using the BIS and BAS scales. The error rate was significantly lower in the reward condition than in the neutral condition. P3 amplitude for correct-rejection trials (i.e., preceding erroneous muscular activity on the wrong hand) was larger in the reward condition than in the neutral condition; however, N2 amplitudes did not differ between the two conditions. These results suggest that monetary rewards may enhance motor inhibition control. Individuals with a higher BIS score exhibited a larger No-go N2 for correct-rejection in the neutral condition. We conclude that No-go N2 amplitude is modulated by avoidance motivation.

A cognitive approach to better understand foraging strategies of the adult domestic hen.

Foraging is known to be one of the most important activities in the behavioral budget of chickens. However, how these animals adapt different foraging strategies to diverse environmental variations is currently poorly understood. To gain further insight into this matter, in the present study, hens were submitted to the sloped-tubes task. In this task, the experimenter can manipulate the information that enables the hens to find a food reward (visible or not), placed in one of two hollow tubes. First, 12 hens were tested under free-choice conditions (no penalty for exhaustive searching in both tubes). Under these conditions, the hens adopted a non-random, side-biased strategy when the food location was not directly visible. Then, we divided the hens in two cohorts of equal size to study deeper the hens' foraging strategy when faced (1) with a different container, or (2) with a restrictive environmental constraint under forced-choice conditions (no food reward if the unbaited tube is visited first). This latter constraint increased the risk of the hen not receiving food. A change in the containers didn't modify the search behavior of the hens. However, in forced-choice conditions when the location of the food was not directly visible, four out of six hens learned to choose by exclusion. We conclude that hens can selectively adapt their foraging strategy to the point of adopting an exclusion performance, depending on available information and environmental constraints (high or low risk).

Risk preference as an outcome of evolutionarily adaptive learning mechanisms: An evolutionary simulation under diverse risky environments.

The optimization of cognitive and learning mechanisms can reveal complicated behavioral phenomena. In this study, we focused on reinforcement learning, which uses different learning rules for positive and negative reward prediction errors. We attempted to relate the evolved learning bias to the complex features of risk preference such as domain-specific behavior manifests and the relatively stable domain-general factor underlying behaviors. The simulations of the evolution of the two learning rates under diverse risky environments showed that the positive learning rate evolved on average to be higher than the negative one, when agents experienced both tasks where risk aversion was more rewarding and risk seeking was more rewarding. This evolution enabled agents to flexibly choose more reward behaviors depending on the task type. The evolved agents also demonstrated behavioral patterns described by the prospect theory. Our simulations captured two aspects of the evolution of risk preference: the domain-specific aspect, behavior acquired through learning in a specific context; and the implicit domain-general aspect, corresponding to the learning rates shaped through evolution to adaptively behave in a wide range of environments. These results imply that our framework of learning under the innate constraint may be useful in understanding the complicated behavioral phenomena.

Serotonin transporter knockout in rats reduces beta- and gamma-band functional connectivity between the orbitofrontal cortex and amygdala during auditory discrimination.

The orbitofrontal cortex and amygdala collaborate in outcome-guided decision-making through reciprocal projections. While serotonin transporter knockout (SERT-/-) rodents show changes in outcome-guided decision-making, and in orbitofrontal cortex and amygdala neuronal activity, it remains unclear whether SERT genotype modulates orbitofrontal cortex-amygdala synchronization. We trained SERT-/- and SERT+/+ male rats to execute a task requiring to discriminate between two auditory stimuli, one predictive of a reward (CS+) and the other not (CS-), by responding through nose pokes in opposite-side ports. Overall, task acquisition was not influenced by genotype. Next, we simultaneously recorded local field potentials in the orbitofrontal cortex and amygdala of both hemispheres while the rats performed the task. Behaviorally, SERT-/- rats showed a nonsignificant trend for more accurate responses to the CS-. Electrophysiologically, orbitofrontal cortex-amygdala synchronization in the beta and gamma frequency bands during response selection was significantly reduced and associated with decreased hubness and clustering coefficient in both regions in SERT-/- rats compared to SERT+/+ rats. Conversely, theta synchronization at the time of behavioral response in the port associated with reward was similar in both genotypes. Together, our findings reveal the modulation by SERT genotype of the orbitofrontal cortex-amygdala functional connectivity during an auditory discrimination task.

Differential patch-leaving behavior during probabilistic foraging in humans and gerbils.

Foraging confronts animals, including humans, with the need to balance exploration and exploitation: exploiting a resource until it depletes and then deciding when to move to a new location for more resources. Research across various species has identified rules for when to leave a depleting patch, influenced by environmental factors like patch quality. Here we compare human and gerbil patch-leaving behavior through two analogous tasks: a visual search for humans and a physical foraging task for gerbils, both involving patches with randomly varying initial rewards that decreased exponentially. Patch-leaving decisions of humans but not gerbils follow an incremental mechanism based on reward encounters that is considered optimal for maximizing reward yields in variable foraging environments. The two species also differ in their giving-up times, and some human subjects tend to overharvest. However, gerbils and individual humans who do not overharvest are equally sensitive to declining collection rates in accordance with the marginal value theorem. Altogether this study introduces a paradigm for a between-species comparison on how to resolve the exploitation-exploration dilemma.

Rationalizing risk aversion in science: Why incentives to work hard clash with incentives to take risks.

Scientific research requires taking risks, as the most cautious approaches are unlikely to lead to the most rapid progress. Yet, much funded scientific research plays it safe and funding agencies bemoan the difficulty of attracting high-risk, high-return research projects. Why don't the incentives for scientific discovery adequately impel researchers toward such projects? Here, we adapt an economic contracting model to explore how the unobservability of risk and effort discourages risky research. The model considers a hidden-action problem, in which the scientific community must reward discoveries in a way that encourages effort and risk-taking while simultaneously protecting researchers' livelihoods against the vicissitudes of scientific chance. Its challenge when doing so is that incentives to motivate effort clash with incentives to motivate risk-taking, because a failed project may be evidence of a risky undertaking but could also be the result of simple sloth. As a result, the incentives needed to encourage effort actively discourage risk-taking. Scientists respond by working on safe projects that generate evidence of effort but that don't move science forward as rapidly as riskier projects would. A social planner who prizes scientific productivity above researchers' well-being could remedy the problem by rewarding major discoveries richly enough to induce high-risk research, but in doing so would expose scientists to a degree of livelihood risk that ultimately leaves them worse off. Because the scientific community is approximately self-governing and constructs its own reward schedule, the incentives that researchers are willing to impose on themselves are inadequate to motivate the scientific risks that would best expedite scientific progress.

Fundraiser engagement, third-party endorsement and crowdfunding performance: A configurational theory approach.

Reward-based crowdfunding is a typical two-sided platform (fundraiser side and backer side) with high information asymmetry. While existing research indicates that signals from fundraisers and backers can impact crowdfunding performance, the interplay among these signals warrants further investigation. Drawing on signaling theory, this study adopts a configurational perspective and utilizes the fsQCA method and linear regression to investigate the combined effects of fundraiser engagement (update and fundraiser comment), third-party endorsement (backer comment and Facebook sharing), and project preparedness (video, image, and description) on crowdfunding performance. Drawing data from the reward-based crowdfunding platform Indiegogo, this research pointed out that these signals cannot generate better crowdfunding performance alone and examined substitution and complementary effects among different signals. Based on the linear regression and fsQCA results, configurations that lead to high crowdfunding performance are identified. We found that project preparedness must work with other signals to produce high crowdfunding performance. Besides, we summarized these configurations into two patterns that may lead to high crowdfunding performance: a fundraiser engagement-driven pattern and a third-party endorsement-driven pattern. This study contributes a configurational perspective and valuable insights into how signals can work together to mitigate information asymmetry in crowdfunding.