Medical schools try to implement selection procedures that will allow them to select the most motivated students for their programs. Though there is a general feeling that selection stimulates student motivation, conclusive evidence for this is lacking. The current study aims to use the perspective of Self-determination Theory (SDT) of motivation as a lens to examine how medical students' motivation differs in relation to different selection procedures. The hypotheses were that 1) selected students report higher strength and autonomous motivation than non-selected students, and 2) recently selected students report higher strength and autonomous motivation than non-selected students and students who were selected longer ago.

According to decades of research on affective motivation in the human brain, approach motivational states are supported primarily by the left hemisphere and avoidance states by the right hemisphere. The underlying cause of this specialization, however, has remained unknown. Here we conducted a first test of the Sword and Shield Hypothesis (SSH), according to which the hemispheric laterality of affective motivation depends on the laterality of motor control for the dominant hand (i.e., the "sword hand," used preferentially to perform approach actions) and the nondominant hand (i.e., the "shield hand," used preferentially to perform avoidance actions).

Social rewards are processed by the same dopaminergic-mediated brain networks as non-social rewards, suggesting a common representation of subjective value. Individual differences in personality and motivation influence the reinforcing value of social incentives, but it remains open whether the pursuit of social incentives is analogously supported by the neural reward system when positive social stimuli are connected to approach behavior. To test for a modulation of neural activation by approach motivation, individuals with high and low approach motivation (BAS) completed implicit and explicit social approach-avoidance paradigms during fMRI. High approach motivation was associated with faster implicit approach reactions as well as a trend for higher approach ratings, indicating increased approach tendencies. Implicit and explicit positive social approach was accompanied by stronger recruitment of the nucleus accumbens, middle cingulate cortex, and (pre-)cuneus for individuals with high compared to low approach motivation. These results support and extend prior research on social reward processing, self-other distinctions and affective judgments by linking approach motivation to the engagement of reward-related circuits during motivational reactions to social incentives. This interplay between motivational preferences and motivational contexts might underlie the rewarding experience during social interactions.

Continually rising global obesity rates present a major challenge to human health. The contribution of Pavlovian motivational processes to overeating and obesity has become increasingly apparent. In humans, brain and behavioral reactivity to food-related stimuli positively correlates with subsequent weight gain. In concordance with this, selectively bred obesity-prone rats show stronger single-outcome Pavlovian-to-instrumental transfer (SO PIT) than obesity-resistant rats, providing support for the hypothesis that enhanced Pavlovian motivation is a pre-existing phenotype of obesity-susceptibility. However, whether obesity-susceptibility in outbred rats is associated with similar enhancements in PIT was unknown. Moreover, given that SO PIT does not distinguish between sensory specific and general affective motivational processes, it was unclear which of these was linked to obesity-susceptibility. Thus, here we determined whether obesity-susceptibility is associated with enhanced Sensory Specific (SS) PIT versus General PIT using both outbred and selectively bred populations. Rats were trained with two action-outcome and three stimulus-outcome associations; two of the Pavlovian and instrumental associations shared a common outcome. During PIT testing, the influence of the Pavlovian stimuli on the two instrumental responses were measured simultaneously. In outbred rats, expression of General PIT was positively correlated with subsequently determined obesity-susceptibility. In selectively bred rats, General PIT was stronger in obesity-prone versus obesity-resistant rats. Jointly, these data show that enhanced affective Pavlovian motivation is tightly linked to obesity vulnerability, supporting a role for phenotypic differences in incentive motivation in vulnerability to obesity. This has important implications for obesity prevention and for the specific neurocircuitry underlying enhanced food-seeking in vulnerable populations.

Motivation is an important phenomenon in the realm of education, particularly in the university fields connected with physical education and sport, where it is necessary to accommodate and balance intellectual abilities and physical fitness. The present study tested motivation levels among university students in the fields connected with physical education and sport in Poland and Turkey. It was based on the Self-Determination Theory (Deci and Ryan, 1985), namely intrinsic motivation, extrinsic motivation and amotivation which impact human behaviour. The Academic Motivation Scale was used (Vallerand et al., 1992). The aims of the study were twofold, first, to crossculturally validate Polish and Turkish versions of the Academic Motivation Scale and second, to identify and compare the motivation to study depending on nationality and gender. Both Polish and Turkish versions of the questionnaire were validated and converted to a four-factorial structure. The findings indicated that Polish and Turkish students' motivation especially differed in amotivation and intrinsic motivation to know and experience stimulation. Moreover, Turkish female students proved to be at the lowest estimate of amotivation.

There is a paucity of information on motivation among U.S. minority triathletes. This study aimed to understand the extrinsic motivation and regulators of Black women triathletes using a modified version of the valid Motivations of Marathoners Scale and semi-structured interviews, for triathletes. The Self Determination Theory guided the dual method assessment of the extrinsic motivators and the regulators external, introjection, and integrated. Using MANOVA, data from (N = 121) triathletes were compared across participant categories of age, body mass index, and distance. Results showed a significant age difference with younger women displaying more motivation. Descriptive means indicated integration as the greatest regulator of motivation. The statements 'to compete with myself' and 'to be more fit,' had the highest means among the women. A sub-sample of 12 interviews were conducted revealing 16 extrinsic themes. Six were related to the regulator integration and two unexpectantly related to the regulator, identified. Integrated themes, including coping mechanisms, finishing course, improvement, accomplishment, and physical awareness were most represented. This research fills gaps of understanding extrinsic motivation and the regulators of a group not previously explored. Future research on motivation among triathletes may benefit knowing how motivations are regulated, as to promote personalized training and participation.

Non-pecuniary sources of motivation are a strong feature of the health care sector and the impact of competitive incentives on behavior may be lower where pecuniary motivation is low. This paper measures the marginal utility of income (MUY) of physicians from a stated-choice experiment, and examines whether this measure influences the association between competition faced by physicians and the prices they charge. We find that physicians are more likely to exploit a lack of competition with higher prices if they have a high MUY.

This study examines the relationship between motivation for body donation to science and personality characteristics using a body donor survey (N=759) conducted by the University Medical Centre Groningen (UMCG) in The Netherlands. The survey expands on anthropological studies that suggest an association between donor motivation and personality.

In humans, optimism is a cognitive construct related to motivation; optimists exert effort, whereas pessimists disengage from effort. In this study, using a recently developed ambiguous-cue interpretation (ACI) paradigm we took the unique opportunity to investigate whether "optimism" as a trait is correlated with motivation in rodents. In a series of ACI tests (cognitive bias screening, CBS), we identified rats displaying "pessimistic" and "optimistic" traits. Subsequently, we investigated the trait differences in the motivation of these rats to gain reward and to avoid punishment using a progressive ratio (PR) schedule of reinforcement paradigm. Although "optimistic" and "pessimistic" animals did not differ in their motivation to avoid punishment, the "optimistic" rats were significantly more motivated to gain reward than their "pessimistic" conspecifics. For the first time, we showed an association between cognitive judgment bias and motivation in an animal model. Because both investigated processes are closely related to mental health and wellbeing, our results may be valuable for preclinical modeling of many psychiatric disorders.

Striatal dopamine (DA) release has long been linked to reward processing, but it remains controversial whether DA release reflects costs or benefits and how these signals vary with motivation. Here, we measure DA release in the nucleus accumbens (NAc) and dorsolateral striatum (DLS) while independently varying costs and benefits and apply behavioral economic principles to determine a mouse's level of motivation. We reveal that DA release in both structures incorporates both reward magnitude and sunk cost. Surprisingly, motivation was inversely correlated with reward-evoked DA release. Furthermore, optogenetically evoked DA release was also heavily dependent on sunk cost. Our results reconcile previous disparate findings by demonstrating that striatal DA release simultaneously encodes cost, benefit, and motivation but in distinct manners over different timescales. Future work will be necessary to determine whether the reduction in phasic DA release in highly motivated animals is due to changes in tonic DA levels.

Incentives are usually expected to increase motivation and cognitive control and to thereby improve performance. A small but growing number of studies have begun to investigate whether the effects of incentive on cognitive performance differ for younger vs. older adults. Most have used attention and cognitive control paradigms, trial-wise implementation of incentive condition, and gain incentives (reward), with only a very few investigating the effects of loss incentives. The present study takes a complementary approach: We tested younger and older adults in a working memory paradigm with loss incentives implemented session-wide (between subjects). We also included self-report measures to ask how loss incentive affected participants' perceptions of the mental demand of the task, as well as their perceived effort, frustration, motivation, distraction, and metacognitive judgments of how well they had performed. This allowed us to test the disparate predictions of different theoretical views: the intuitive hypothesis that incentive should increase motivation and performance, the motivational shift proposal that older adults are especially motivated to avoid losses (Freund and Ebner, 2005), a heuristic "positivity effect" perspective that older adults ignore losses (Brassen et al., 2012; Williams et al., 2017), and a more nuanced view that suggests that when negative information is unavoidable and increases perceived costs, older adults may instead disengage from the situation (Charles, 2010; Hess, 2014). The results seemed most consistent with the more nuanced view of the positivity effect. While neither group showed incentive-related performance differences, both younger and older adults reported greater perceived demand and frustration under loss incentive, especially in the most challenging conditions. Loss incentive increased the accuracy of immediate metacognitive judgments, but reduced the accuracy of later, more global judgments of competency for older adults. Self-report measures suggested that the loss incentive manipulation was distracting to young adults and demotivating for older adults. The results suggest a need for caution in generalizing from existing studies to everyday life, and that additional studies parameterizing critical aspects of task design and incentive manipulation are needed to fully understand how incentives affect cognition and motivation in younger and older adults.

Most living organisms have a circadian timing system adapted to optimize the daily rhythm of exposure to the environment. This circadian system modulates several behavioral and physiological processes, including the response to natural and drug rewards. Food is the most potent natural reward across species. Food-seeking is known to be mediated by dopaminergic and serotonergic transmission in cortico-limbic pathways. In the present work, we show evidence of a circadian modulation of motivation for food reward in young (4-months old) and aged (over 1.5 years old) C57BL/6 mice. Motivation was assayed through the progressive ratio (PR) schedule. Mice under a 12:12 light/dark (LD) cycle exhibited a diurnal rhythm in motivation, becoming more motivated during the night, coincident with their active phase. This rhythm was also evident under constant dark conditions, indicating the endogenous nature of this modulation. However, circadian arrhythmicity induced by chronic exposure to constant light conditions impaired the performance in the task causing low motivation levels. Furthermore, the day/night difference in motivation was also evident even without caloric restriction when using a palatable reward. All these results were found to be unaffected by aging. Taken together, our results indicate that motivation for food reward is regulated in a circadian manner, independent of the nutritional status and the nature of the reward, and that this rhythmic modulation is not affected by aging. These results may contribute to improve treatment related to psychiatric disorders or drugs of abuse, taking into account potential mechanisms of circadian modulation of motivational states.

Developments in chemotherapy have led to changes in cancer care in Japan, with the government promoting a transition to outpatient chemotherapy. This requires patients and their families to participate more actively in treatment than in the past. However, it remains unclear how patients' motivation for medical treatment affects clinical consultations with their physicians. To investigate this, we developed a psychological index called the Achievement Motive Index for Medical Treatment (AMI-MeT), which comprises self-derived achievement motivation (AMS) and achievement motivation derived from others (AMO). However, its factor structure has not yet been confirmed in populations other than healthy university students. Thus, the aims of this study were to confirm the factor structure of the AMI-MeT in other groups and to determine the convergent and divergent validity of the AMI-MeT.

The Self-Determination Theory (SDT) establishes that human motivations can take different forms (e.g., amotivation, extrinsic and intrinsic motivation), yet it is only recently that the theory has been advanced to explain how these different forms combine to influence temporary agency workers' (TAWs) affective commitment and their perception over the human resources practices (HRP) applied. We tested this theory with data from seven temporary agency companies (N = 3766). Through latent profile analysis (LPA) we identified five distinct motivation profiles and found that they differed in their affective commitment to the agency and to the client-company, and in their perception of HRP. We verified that temporary agency workers in more intrinsic profiles had more positive outcomes and a better perception of the investment made by the companies, than did TAWs in more extrinsic profiles. Additionally, when TAWs were able to integrate the reasons for being in this work arrangement, the negative effect of the extrinsic motivation was attenuated, and it was possible to find moderated profiles in which TAWs also showed more positive results than TAWs with only extrinsic motives. These differences are consistent with the notion that a motivation profile provides a context that determines how the individual components are experienced. Theoretical and practical implications of this context effect are discussed.

Animal behavior is motivated by internal drives, such as thirst and hunger, generated in hypothalamic neurons that project widely to many brain areas. We find that water-restricted mice maintain stable, high-level contrast sensitivity and brief reaction time while performing a visual task, but then abruptly stop and become disengaged. Mice consume a significant amount of water when freely provided in their home cage immediately after the task, indicating that disengagement does not reflect cessation of thirst. Neuronal responses of V1 neurons are reduced in the disengaged state, but pupil diameter does not decrease, suggesting that animals' reduced level of arousal does not drive the transition to disengagement. Our findings indicate that satiation level alone does not have an instructive role in visually guided behavior and suggest that animals' behavior is governed by cost-benefit analysis that can override thirst signals.

The dopamine projection from ventral tegmental area (VTA) to nucleus accumbens (NAc) is critical for motivation to work for rewards and reward-driven learning. How dopamine supports both functions is unclear. Dopamine cell spiking can encode prediction errors, which are vital learning signals in computational theories of adaptive behaviour. By contrast, dopamine release ramps up as animals approach rewards, mirroring reward expectation. This mismatch might reflect differences in behavioural tasks, slower changes in dopamine cell spiking or spike-independent modulation of dopamine release. Here we compare spiking of identified VTA dopamine cells with NAc dopamine release in the same decision-making task. Cues that indicate an upcoming reward increased both spiking and release. However, NAc core dopamine release also covaried with dynamically evolving reward expectations, without corresponding changes in VTA dopamine cell spiking. Our results suggest a fundamental difference in how dopamine release is regulated to achieve distinct functions: broadcast burst signals promote learning, whereas local control drives motivation.

Gender differences in navigation performance are a recurrent and controversial topic. Previous research suggests that men outperform women in navigation tasks and that men and women exhibit different navigation strategies. Here, we investigate whether motivation to complete the task moderates the relationship between navigation performance and gender. Participants learned the locations of landmarks in a novel virtual city. During learning, participants could trigger a top-down map that depicted their current position and the locations of the landmarks. During testing, participants were divided into control and treatment groups and were not allowed to consult the map. All participants were given 16 minutes to navigate to the landmarks, but those in the treatment group were monetarily penalized for every second they spent completing the task. Results revealed a negative relationship between physiological arousal and the time required to locate the landmarks. In addition, gender differences in strategy were found during learning, with women spending more time with the map and taking 40% longer than men to locate the landmarks. Interestingly, an interaction between gender and treatment group revealed that women in the control group required more time than men and women in the treatment group to retrieve the landmarks. During testing, women in the control group also took more circuitous routes compared to men in the control group and women in the treatment group. These results suggest that a concurrent and relevant stressor can motivate women to perform similarly to men, helping to diminish pervasive gender differences found in the navigation literature.

Organisms have evolved to approach pleasurable opportunities and to avoid or escape from aversive experiences. These 2 distinct motivations are referred to as approach and avoidance/escape motivations and are both considered vital for survival. Despite several recent advances in understanding the neurobiology of motivation, most studies addressed approach but not avoidance/escape motivation. Here we develop a new experimental paradigm to quantify avoidance/escape motivation and examine the pharmacological validity.

Corticotropin-releasing factor (CRF) neural systems are important stress mechanisms in the central amygdala (CeA), bed nucleus of stria terminalis (BNST), nucleus accumbens (NAc), and related structures. CRF-containing neural systems are traditionally posited to generate aversive distress states that motivate overconsumption of rewards and relapse in addiction. However, CRF-containing systems may alternatively promote incentive motivation to increase reward pursuit and consumption without requiring aversive states.

The role of the melanocortin (MC) system in feeding behavior is well established. Food intake is potently suppressed by central infusion of the MC 3/4 receptor agonist α-melanocyte stimulating hormone (α-MSH), whereas the MC 3/4 receptor inverse-agonist Agouti Related Peptide (AGRP) has the opposite effect. MC receptors are widely expressed in both hypothalamic and extra-hypothalamic brain regions, including nuclei involved in food reward and motivation, such as the nucleus accumbens (NAc) and the ventral tegmental area. This suggests that MCs modulate motivational aspects of food intake. To test this hypothesis, rats were injected intracerebroventricularly with α-MSH or AGRP and their motivation for sucrose was tested under a progressive ratio schedule of reinforcement. Food motivated behavior was dose-dependently decreased by α-MSH. Conversely, AGRP increased responding for sucrose, an effect that was blocked by pretreatment with the dopamine receptor antagonist α-flupenthixol. In contrast to progressive ratio responding, free intake of sucrose remained unaltered upon α-MSH or AGRP infusion. In addition, we investigated whether the effects of α-MSH and AGRP on food motivation were mediated by the NAc shell. In situ hybridization of MC3 and MC4 receptor expression confirmed that the MC4 receptor was expressed throughout the NAc, and injection of α-MSH and AGRP into the NAc shell caused a decrease and an increase in motivation for sucrose, respectively. These data show that the motivation for palatable food is modulated by MC4 receptors in the NAc shell, and demonstrate cross-talk between the MC and dopamine system in the modulation of food motivation.