Reward Experience Research Articles

How Culture and Musical Engagement Shape Musical Reward Sensitivity in Danish Teens: A Validation Study of the Danish Barcelona Musical Reward Questionnaire With 4641 Adolescents.

The ability to convey emotions and induce pleasure is one of the most important aspects of the way that music becomes meaningful to humans. Affective responses to music are specific to both cultural and personal preferences, but little is known about the individual variability in adolescence. The Barcelona Music Reward Questionnaire (BMRQ) is a psychometric measure that identifies five factors associated with musical pleasure: Musical Seeking, Emotional Evocation, Mood Regulation, Social Reward, and Sensory-Motor. With this study, we aimed to validate the BMRQ in Danish teens and to explore the differences in music reward experiences in relation to the amount of musical activity, between genders and over ages. Approximately 30,000 Danish adolescents participated in a mass experiment with a subset (N = 4641, 51.2% girls, age range = 13-19 years old) responding to (1) a Danish adaptation of the BMRQ and (2) the Concurrent Musical Activities (CCM) Questionnaire. Both exploratory and confirmatory factor analyses were applied, and a seven-factor model of the BMRQ was found to fit the Danish adolescent population. The seven-factor version of the Danish BMRQ was due to the split of the dimensions "Sensory-Motor" and "Social Reward" into two further subfactors. The students with a higher amount of musical engagement scored higher across all dimensions. In particular, the higher the musical engagement, the higher scores were found for the facet of musical pleasure related to the sharing of musical activities, especially in the earliest stages of adolescence. Furthermore, we found that sensitivity to music generally tends to increase with age, and that girls reported overall to be more sensitive to music than boys in the dimension related to evocation of emotions. A slightly different model of the BMRQ has to be taken into account when testing the Danish adolescent population. In addition to utilizing the Danish version of the BMRQ on a large sample of adolescents, this study may provide insight into the relationship between changes in the level of musical reward depending on amount of musical engagement and how musical reward unfolds within and between genders and across age groups during this developmental stage.

Sex differences in appeal, reward, and sensory experience of E-cigarette flavors among adults who smoke cigarettes

ObjectiveFlavors enhance nicotine e-cigarette appeal by altering sensory experience. Females may be more sensitive to tobacco-associated cues and uniquely affected by flavor. The current study is an exploratory analysis to examine differences by sex on reward, appeal, and sensory experience of popular e-cigarette flavors. MethodsAdults (N = 121) who use cigarettes (≥1 cigarette/day) were enrolled in a laboratory study in which they vaped four e-cigarette flavors (tobacco, cherry, menthol, vanilla; in separate lab sessions) in one of two freebase nicotine concentrations (6 mg/ml,18 mg/ml). Following exposures, participants rated e-cigarette reward using the Drug Effects Questionnaire (DEQ), flavor and overall e-cigarette appeal using Labeled Hedonic Scales (LHS), and intensity of flavor, irritation, coolness, fruitiness, and sweetness using Generalized Labeled Magnitude Scales (gLMS). Linear mixed models were conducted for outcomes to analyze effects of sex, flavor, and sex x flavor interaction. ResultsFor DEQ ratings, there was a trend (p = .08) toward a sex x flavor interaction, in which menthol flavor produced more reward than other flavors for females, but not males. For LHS ratings, there was a significant sex x flavor interaction (p = .03) for overall e-cigarette experience with females but not males rating menthol higher than other flavors. All gLMS scales but irritation showed that females generally had greater differences between flavors compared to males (ps ≤ 0.03). ConclusionMenthol in e-cigarettes may play an important role in mediating appeal and/or reward among females. This may be due in part to their ability to better detect sensory effects of e-cigarettes.

Counteract Anhedonia! Introducing an Online-Training to Enhance Reward Experiencing - A Pilot Study.

Anhedonia is a risk factor for a severe course of depression but is often not adequately addressed in psychotherapy. This study presents the Training to Enhance Reward Experience (T-REx), a novel self-help approach that uses savoring and mental imagery to target impairments in reward experience associated with anhedonia. We aimed to examine feasibility and acceptability of T-REx and exploratively investigated its effects on anhedonia and other clinical variables. In an online, randomized controlled trial, 79 subjects participated for five days in T-REx or the active control condition Gratitude Writing (GW). We assessed changes in anhedonia, depression, and active behavior at inclusion, after the waiting period, post-intervention and at follow-up. The intervention effects were examined for the full sample and an anhedonic sub-sample. T-REx and GW were equally feasible and clearly accepted by the sample. Both interventions significantly reduced depressive symptoms and increased behavioral activation. Although there was no significant main effect of the interventions, between-group differences were observed for depressive symptoms and active behavior at post-intervention and follow-up, favoring T-REx. Further, within-group changes for T-REx were larger than for GW. The observed effects had a greater magnitude in the anhedonic sub-sample, suggesting that individuals with more pronounced anhedonic symptoms derived greater benefit from the interventions. This first study of T-REx provides promising results that should prompt further investigations of T-REx in clinical samples. The results suggest that T-REx has a positive effect on depression symptoms and active behavior. Further, its potential as a valuable adjunct to behavioral activation interventions is discussed.

Sources of Organizational Power among Administrators Working in the Education Directorates at Zarqa Governorate /Jordan

The study aimed to identify the sources of organizational power of administrators working in the directorates of education in Zarqa Governorate / Jordan and the impact of the variables (gender, academic qualification, job title and experience) on that. The study sample consisted of (218) employees. To achieve the aim of the study a questionnaire was developed consisted of (52) items distributed on six domains: official, reward, experience, reference, punishment and information). Validity and reliability of the tool were verified. The results of the study showed that the degree of estimation of the practice of organizational power sources among administrators working in the directorates of education in Zarqa Governorate / Jordan was medium, and the fields were ranked in descending order, respectively (the domain of experience, the domain of formality, the domain of information, the domain of reference, the domain of reward and the domain of punishment). The results also showed that there were statistically significant differences at the level of significance (α ≤ 0.05) due to job title variable, on the domains (reward strength, experience strength, reference strength, and information strength) and overall score, and the differences were in favor of the department member’s name. There were no differences in the impact of the job title on the rest of the fields. The results showed that there were no statistically significant differences at the level of significance (α ≤ 0.05) due to the variables of gender, educational qualification and years of experience. In light of the results, the researchers recommended a set of recommendations, the most important of which are: Strengthening the practice of the source of expertise based on professional reference by increasing the degree of awareness of the requirements of the job role.

The role of intrinsic reward in adolescent word learning.

Relatively little work has focused on why we are motivated to learn words. In adults, recent experiments have shown that intrinsic reward signals accompany successful word learning from context. In addition, the experience of reward facilitated long-term memory for words. In adolescence, developmental changes are seen in reward and motivation systems as well as in reading and language systems. Here, in the face of this developmental change, we ask whether adolescents experience reward from word learning, and how the reward and memory benefit seen in adults is modulated by age. We used a naturalistic reading paradigm, which involved extracting novel word meanings from sentence context without the need for explicit feedback. By exploring ratings of enjoyment during the learning phase, as well as recognition memory for words a day later, we assessed whether adolescents show the same reward and learning patterns as adults. We tested 345 children between the ages of 10-18 (N>84 in each 2-year age-band) using this paradigm. We found evidence for our first prediction: children aged 10-18 report greater enjoyment for successful word learning. However, we did not find evidence for age-related change in this developmental period, or memory benefits. This work gives us greater insight into the process of language acquisition and sets the stage for further investigations of intrinsic reward in typical and atypical development. RESEARCH HIGHLIGHTS: We constantly learn words from context, even in the absence of explicit rewards or feedback. In adults, intrinsic reward experienced during word learning is linked to a dopaminergic circuit in the brain, which also fuels enhancements in memory for words. We find adolescents also report enhanced reward or enjoyment when they successfully learn words from sentence context. The relationship between reward and learning is maintained between the ages of 10 and 18. Unlike in adults, we did not observe ensuing memory benefits.

Basolateral amygdala parvalbumin interneurons coordinate oscillations to drive reward behaviors

The basolateral amygdala (BLA) mediates both fear and reward learning.1,2 Previous work has shown that parvalbumin (PV) interneurons in the BLA contribute to BLA oscillatory states integral to fear expression.3,4,5,6,7 However, despite it being critical to our understanding of reward behaviors, it is unknown whether BLA oscillatory states and PV interneurons similarly contribute to reward processing. Local field potentials in the BLA were collected as male and female mice consumed sucrose reward, where prominent changes in the beta band (15-30Hz) emerged with reward experience. During consumption of one water bottle during a two-water-bottle choice test, rhythmic optogenetic stimulation of BLA PVs produced a robust bottle preference, showing that PVs can sufficiently drive reward seeking. Finally, to demonstrate that PV activity is necessary for reward value use, PVs were chemogenetically inhibited following outcome devaluation, rendering mice incapable of using updated reward representations to guide their behavior. Taken together, these experiments provide novel information about the physiological signatures of reward while highlighting BLA PV interneuron contributions to behaviors that are BLA dependent. This work builds upon established knowledge of PV involvement in fear expression and provides evidence that PV orchestration of unique BLA network states is involved in both learning types.

Object-based attention is accentuated by object reward association.

Humans use selective attention to prioritize visual features, like color or shape, as well as discrete spatial locations, and these effects are sensitive to the experience of reward. Reward-associated features and locations are accordingly prioritized from early in the visual hierarchy. Attention is also sensitive to the establishment of visual objects: selection of one constituent object part often leads to prioritization of other locations on that object. But very little is known about the influence of reward on this object-based control of attention. Here we show in four experiments that reward prioritization and object prioritization interact in visual cognition to guide selection. Experiment 1 establishes groundwork for this investigation, showing that reward feedback does not negate object prioritization. In Experiment 2, we corroborate the hypothesis that reward prioritization and object prioritization emerge concurrently. In Experiment 3, we find that reward prioritization and object prioritization sustain and interact in extinction, when reward feedback is discontinued. We verify this interaction in Experiment 4, linking it to task experience rather than the strategic utility of the reward association. Results suggest that information gathered from locations on reward-associated objects gains preferential access to cognition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Enhancing Stability and Performance in Mobile Robot Path Planning with PMR-Dueling DQN Algorithm.

Path planning for mobile robots in complex circumstances is still a challenging issue. This work introduces an improved deep reinforcement learning strategy for robot navigation that combines dueling architecture, Prioritized Experience Replay, and shaped Rewards. In a grid world and two Gazebo simulation environments with static and dynamic obstacles, the Dueling Deep Q-Network with Modified Rewards and Prioritized Experience Replay (PMR-Dueling DQN) algorithm is compared against Q-learning, DQN, and DDQN in terms of path optimality, collision avoidance, and learning speed. To encourage the best routes, the shaped Reward function takes into account target direction, obstacle avoidance, and distance. Prioritized replay concentrates training on important events while a dueling architecture separates value and advantage learning. The results show that the PMR-Dueling DQN has greatly increased convergence speed, stability, and overall performance across conditions. In both grid world and Gazebo environments the PMR-Dueling DQN achieved higher cumulative rewards. The combination of deep reinforcement learning with reward design, network architecture, and experience replay enables the PMR-Dueling DQN to surpass traditional approaches for robot path planning in complex environments.

Brain connectivity changes to fast versus slow dopamine increases

The rewarding effects of stimulant drugs such as methylphenidate (MP) depend crucially on how fast they raise dopamine in the brain. Yet how the rate of drug-induced dopamine increases impacts brain network communication remains unresolved. We manipulated route of MP administration to generate fast versus slow dopamine increases. We hypothesized that fast versus slow dopamine increases would result in a differential pattern of global brain connectivity (GBC) in association with regional levels of dopamine D1 receptors, which are critical for drug reward. Twenty healthy adults received MP intravenously (0.5 mg/kg; fast dopamine increases) and orally (60 mg; slow dopamine increases) during simultaneous [11C]raclopride PET-fMRI scans (double-blind, placebo-controlled). We tested how GBC was temporally associated with slow and fast dopamine increases on a minute-to-minute basis. Connectivity patterns were strikingly different for slow versus fast dopamine increases, and whole-brain spatial patterns were negatively correlated with one another (rho = −0.54, pspin < 0.001). GBC showed “fast>slow” associations in dorsal prefrontal cortex, insula, posterior thalamus and brainstem, caudate and precuneus; and “slow>fast” associations in ventral striatum, orbitofrontal cortex, and frontopolar cortex (pFDR < 0.05). “Fast>slow” GBC patterns showed significant spatial correspondence with D1 receptor availability (estimated via normative maps of [11C]SCH23390 binding; rho = 0.22, pspin < 0.05). Further, hippocampal GBC to fast dopamine increases was significantly negatively correlated with self-reported ‘high’ ratings to intravenous MP across individuals (r(19) = −0.68, pbonferroni = 0.015). Different routes of MP administration produce divergent patterns of brain connectivity. Fast dopamine increases are uniquely associated with connectivity patterns that have relevance for the subjective experience of drug reward.

High perceived stress is associated with decreased sensory-specific satiety in humans

Previous studies have shown that chronic stress increases food intake. One possible mechanism may be due to altered sensory-specific satiety (SSS) among people with high level of chronic stress. In the current study, seventy-six participants were divided into either high-stress or low-stress groups according to their Perceived Stress Scale (PSS) scores. Participants were assigned to consume one of two foods (banana milk and corn soup) ad libitum until they felt comfortably satiated. Before and after eating, participants rated their liking and wanting for the flavor and the odor (via retronasal and orthonasal routes) of the eaten and uneaten foods. Individual interoceptive sensibility and eating behavior were measured using the Multidimensional Assessment of Interoceptive Awareness (MAIA) and Reasons Individuals Stop Eating Questionnaire (RISE-Q-15), respectively. Compared to the low-stress group, the high-stress group demonstrated blunted SSS to the whole food flavor. No significant difference was found for olfactory-specific satiety (retronasal or orthonasal) between the two groups. In addition, across the whole sample of participants, MAIA total score was positively associated with the magnitude of SSS (r = 0.29, p = 0.01). These results indicate that chronic perceived stress may play a role in the experience of reward during eating.

Learning modifies attention during bumblebee visual search

The role of visual search during bee foraging is relatively understudied compared to the choices made by bees. As bees learn about rewards, we predicted that visual search would be modified to prioritise rewarding flowers. To test this, we ran an experiment testing how bee search differs in the initial and later part of training as they learn about flowers with either higher- or lower-quality rewards. We then ran an experiment to see how this prior training with reward influences their search on a subsequent task with different flowers. We used the time spent inspecting flowers as a measure of attention and found that learning increased attention to rewards and away from unrewarding flowers. Higher quality rewards led to decreased attention to non-flower regions, but lower quality rewards did not. Prior experience of lower rewards also led to more attention to higher rewards compared to unrewarding flowers and non-flower regions. Our results suggest that flowers would elicit differences in bee search behaviour depending on the sugar content of their nectar. They also demonstrate the utility of studying visual search and have important implications for understanding the pollination ecology of flowers with different qualities of reward.Significance statementStudies investigating how foraging bees learn about reward typically focus on the choices made by the bees. How bees deploy attention and visual search during foraging is less well studied. We analysed flight videos to characterise visual search as bees learn which flowers are rewarding. We found that learning increases the focus of bees on flower regions. We also found that the quality of the reward a flower offers influences how much bees search in non-flower areas. This means that a flower with lower reward attracts less focussed foraging compared to one with a higher reward. Since flowers do differ in floral reward, this has important implications for how focussed pollinators will be on different flowers. Our approach of looking at search behaviour and attention thus advances our understanding of the cognitive ecology of pollination.

Impact of user engagement on virtual reality behavioral response from the human–computer interaction perspective toward a service context: A hybrid statistics and machine learning approach

Owing to recent uncertainty in the service sector, new attractive ways, such as virtual reality, have been adopted by online sites to provide products and services to individual users in the tourism context. Based on human–computer interaction user engagement and the domain segmentation innovativeness theory, we develop and test a theoretical framework to examine the impact of key user engagement drivers on in-person tour intentions as behavioral responses using the partial least squares structural equation model and a neural network with activation function analysis as the new two-stage approach. According to a survey sample of visitors' responses as the case, the results demonstrate that a) user engagement, including aesthetic appeal, focused attention, perceived usability, and reward experience, improves attitudes toward virtual reality; b) product-possessing innovativeness positively moderates the relationships between attitude toward virtual reality and in-person tour intentions; c) information-possessing innovativeness negatively moderates the relationships between the attitude toward virtual reality and in-person tour intentions; d) focused attention and reward experience show both linear high performance and nonlinear importance; and e) activation function analysis could further improve the accuracy of prediction.

Rhythm and Reading Abilities

This study was conducted to investigate the previously indicated causal relationship between reading impairment and difficulties in rhythm perception in an adult sample. In our study the comparison was made between the family risk for dyslexia and the no-risk for dyslexia groups to assess the possibility of shared risk factors. We hypothesized that a relationship exists between reading deficits and lower performance in rhythm perception within the family risk for dyslexia participant group. The participants were young adults (N = 119, aged from 20 to 48 years old). We assessed the reading abilities, rhythm perception performance and memory performance, and sensorimotor music reward experiences of our participants. Our results indicate that in adulthood rhythm perception appears to correlate with aspects of memory function, rather than with measures of reading fluency. Our results also suggest an indirect relationship between rhythm perception and word text reading fluency through short-term memory within the family risk for dyslexia group. A weak positive correlation between sensorimotor musical reward experience and pseudoword reading fluency was detected as well. We suggest family risk for dyslexia as an additional variable in future research.

Regulation of ethanol-mediated dopamine elevation by glycine receptors located on cholinergic interneurons in the nucleus accumbens.

Alcohol use disorder is one of the major psychiatric disorders worldwide, and there are many factors and effects contributing to the disorder, for example, the experience of ethanol reward. The rewarding and reinforcing properties of ethanol have been linked to activation of the mesolimbic dopamine system, an effect that appears to involve glycine receptors (GlyRs) in the nucleus accumbens. On which neuronal subtypes these receptors are located is, however, not known. The aim of this study was to explore the role of GlyRs on cholinergic interneurons (CIN) in sustaining extracellular dopamine levels and in ethanol-induced dopamine release. To this end, CIN were ablated by anti-choline acetyltransferase-saporin administered locally in the nucleus accumbens of male Wistar rats. Changes in dopamine levels induced by ablation, ethanol and/or a GlyR antagonist were monitored using in vivo microdialysis. The GlyRs antagonist strychnine depressed extracellular dopamine in a similar manner independent on local ablation, suggesting that GlyRs on CIN are not important for sustaining the extracellular dopamine tone. However, a low concentration of strychnine hampered ethanol-induced dopamine release in sham-treated animals, whilst no reduction was seen in ablated animals, suggesting that GlyRs located on CIN are involved in ethanol-induced dopamine release. Further, in ablated rats, ethanol-induced increases of the extracellular levels of the GlyR agonists glycine and taurine were attenuated. In conclusion, this study suggests that CIN are not important for GlyR-mediated regulation of basal dopamine output, but that CIN ablation blunts the ethanol-induced dopamine release, putatively by reducing the release of GlyR agonists.

Representational shifts: increasing motivation for bottled water through simulation-enhancing advertisements

BackgroundDespite its numerous health benefits, consumers’ daily water consumption is below recommend levels while soft drink consumption remains high. Previous research has shown that the degree to which drinks are cognitively represented in terms of consumption and enjoyment (i.e., through simulations of consumption and reward) predicts desire and intake. Here, we examined whether simulation-enhancing advertisements that frame water in terms of consumption and reward change cognitive representations and increase motivation for a fictitious bottled water.MethodsIn three pre-registered online experiments (Nexp1 = 984; Nexp2 = 786; Nexp3 = 907), UK participants viewed three advertisements that either highlighted the rewarding consumption experience of water (e.g., “Refresh all your senses with this smooth, cool water”; simulation-enhancing ads), the health consequences of drinking water (e.g., “This water takes care of your health”; health-focused ads), or control ads. We assessed cognitive representations of the bottled water with a semantic feature production task, and we coded the words used as consumption and reward features or positive long-term health consequences features. We assessed motivation through ratings of the attractiveness of the water (Exp. 1 only), desire to drink it, and willingness to pay for it (WTP).ResultsIn line with our hypotheses, participants represented the bottled water more in terms of consumption and reward after viewing simulation-enhancing advertisements, and more in terms of positive long-term health consequences after viewing health-focused advertisements. There was no direct effect of advertisement condition on motivation ratings. However, significant indirect effects showed that simulation-enhancing advertisements increased desire and WTP through the proportion of consumption and reward features, whereas health-focused advertisements increased motivation through an increase in the proportion of positive long-term health consequences features. The effects through consumption and reward were stronger.ConclusionsThese findings are consistent with research suggesting that the experience of immediate reward from drinking water underlies intake. Public health interventions should emphasize the enjoyment of drinking water, rather than the long-term health benefits.

The value of mere completion.

The positivity of goal completion is reinforced through everyday experiences of social praise and instrumental reward. Here we investigated whether, in line with this self-regulatory emphasis, people value completion opportunities in and of themselves. Across six experiments we found that adding an arbitrary completion opportunity to a lower-reward task increased the likelihood that participants would choose to work on that task over a higher-reward alternative that did not offer a completion opportunity. This occurred for extrinsic reward tradeoffs (Experiments 1, 3, 4, and 5) and intrinsic reward tradeoffs (Experiments 2 and 6), and it persisted even when participants explicitly noted the rewards of each task (Experiment 3). We sought but did not find evidence that the tendency is moderated by participants' stable or momentary level of concern with monitoring multiple responsibilities (Experiments 4 and 5, respectively). We did find that the opportunity to complete the final step in a sequence was particularly attractive: Setting the lower-reward task closer to completion (but with completion still out of reach) did increase its choice share, but setting the lower-reward task with completion distinctly in reach increased its choice share even more (Experiment 6). Together, the experiments imply that people sometimes behave as if they value completion itself. In everyday life, the allure of mere completion may influence the tradeoffs people make when prioritizing their goals. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

How expected and experienced reward and relief contribute to gaming-related mental imagery and gaming frequency in daily life: Testing a dual pathway hypothesis

AbstractBackground and aimsResearch on the development of gaming disorder assumes that the quality of reinforcement learning as well as the content of use expectancies are initially rewarding in the early stages of the addictive behavior and becomes steadily more compensatory in the later stages. This assumed transition could be reflected in gaming-related mental imagery as well as the decision to play videogames in daily life.MethodsWe recruited 127 individuals who play videogames. Following a strict diagnostic procedure, individuals were either classified as showing casual or at-risk gaming patterns. The experience and expectancy of reward and relief were assessed in the laboratory, followed by a 14-day ambulatory assessment asking for gaming-related mental imagery intensity and playing frequency. Besides group differences, we tested a gratification and a compensation pathway in a structural equation model among groups separately.ResultsResults indicate that mental imagery and playing frequency as well as reinforcement processes and use expectancies are heightened among individuals showing at-risk gaming patterns as compared to casual gaming patterns. Gaming-related mental imagery was only predicted by compensation among individuals showing casual gaming patterns, and we found no significant predictions for daily gaming frequency in any of the models.Discussion and conclusionsThe results implicate that individuals with at-risk gaming patterns might hold stronger learned reinforcement contingencies. Daily usage seems unaffected by these contingencies, possibly indicative of habitualized behaviors. Additionally, the results provide some support for the consideration of imaginal desire thoughts as a specific coping mechanism in the context of gaming behaviors.

Self-control and emotional exhaustion: mediating role of effort-reward imbalance and emotional demands

PurposeThe purpose of this paper is to study the relationship between trait self-control (TSC) and emotional exhaustion, and to examine the mediating role of effort–reward imbalance (ERI) and emotional demands.Design/methodology/approachA quantitative study was conducted using data from 441 employees working in different organizations in the information technology sector in India. PROCESS macro with a bootstrap sample size of 5,000 was used for mediation analysis.FindingsTSC demonstrated a significant negative relationship with emotional exhaustion. Results indicated the crucial role played by ERI and emotional demands in influencing the emotional exhaustion of employees with higher TSC.Originality/valueThis study adds substantially to our knowledge of the role of TSC in employee experiences of emotional exhaustion. Results suggest how employees’ ERI perceptions and experiences of emotional demands determine whether higher TSC would reduce experiences of exhaustion. This adds to the knowledge of positive outcomes of self-control while throwing some light on why the use of self-control does not always incur a psychological cost, as suggested by some studies. The findings suggest that self-control is an individual resource that has the ability to alleviate emotional exhaustion through its influence on employees‘ effort–reward perceptions and experiences of emotional demands.

Understanding Attentional Functioning in Adult Attention Deficit Hyperactivity Disorder—Could This Improve Diagnostic Specificity?

The diagnostic criteria for attention deficit hyperactivity disorder (ADHD) reflect the behavioural and functional outcomes of cognitive processes. Historically they have been based on external observations and lack specificity: clinical cohorts of children meeting diagnostic criteria show that around 40% may also meet diagnostic criteria for oppositional defiant disorder (ODD). We have proposed a clinical model to explain this: the Mental Effort Reward Imbalances model of ADHD (MERIM). This model views the lower levels of task completion that underlie several of the diagnostic criteria for ADHD as being due to a summation of deficits in executive functioning and reward processing. The subjective experience of inadequate reward from task completion may explain the reduced motivation, negativity, and oppositional attitude associated with ODD. The hypothesis for this study is that descriptions of affected individuals' attentional characteristics could be more specific for the executive functioning deficits associated with ADHD than the current symptom-based approaches. To test whether this might be usable in practice, we conducted a workshop that aimed to characterise in depth the patterns of attention experienced by adults with ADHD and how they impact functioning. Three main patterns were described: (1) complete lapses in attention; (2) partial attention to a task; (3) attending to multiple tasks and distractions, either simultaneously or in rapid sequence. All of these resulted in reduced productivity. They also described strategies for managing their attention deficits. Some people used distractions positively, to stimulate the mind to remain active and engaged rather than losing focus. Multi-tasking could also achieve this by providing higher levels of stimulation, however, the stimulation could itself become a distraction. Interest or stress might maintain engagement; extremes could sometimes lead to hyperfocusing, which was typically infrequent but could be highly productive. Focusing on executive functions may improve diagnostic sensitivity, as the current criteria fail to identify people who function adequately due to their use of strategies that mitigate the effects of their attentional deficits. Such people may present with secondary depression or anxiety rather than clear, behavioural symptoms of ADHD. With further development, the approach described in this paper may provide a more simple and fundamental way of recognising ADHD within the community. In the longer term, focusing more specifically on executive functions may provide cohorts with a 'purer' form of ADHD for scientific study.

Rats chirp with their mouth full: During an experimental meal, adult male Wistar rats emitted flat ultrasonic vocalisations upon feeding.

Rats produce ultrasonic vocalisation (USVs) that are classified into different types, based on their average frequency. In pups 40 kHz USVs are produced upon social isolation, and in adults USVs can be associated with affective states and specific behavioural patterns (i.e., appetitive 50 kHz vocalisations of frequency range 30-100 kHz, or aversive 20 kHz vocalisations of frequency range 18-30 kHz). Generally, USVs of frequency around 50 kHz are linked to activation of brain reward pathways, during anticipation or experience of rewarding stimuli. Previous studies have described several subtypes of 50 kHz USVs, according to their acoustic properties. We asked whether USV production might be relevant to feeding behaviour. We recorded USVs from 14-week old adult rats during the satisfaction of a physiological need: refeeding following mild food deprivation (17 h overnight fast). We analysed a 10 min consummatory phase, preceded by a 10 min anticipatory phase, as a control for the experimental meal. Following identification of USV subtypes, we applied frequentist and Bayesian (Monte Carlo shuffling) statistical analyses to investigate the relationship between USV emission and rat behaviour. We found that it was not total USV quantity that varied in response to food consumption, but the subtype of USV produced. Most importantly we found that rats who feed tend to produce flat USVs of a frequency around 40 kHz. Beyond the previous reports of circumstantial association feeding-flat USVs, our observation directly correlate vocalisation and ingestive behaviour. Our study highlights that, in addition to quantification of the production rate, study of USV subtypes might inform us further on rat consummatory behaviour. Since this vocalisation behaviour can have a communicative purpose, those findings also illustrate nutrition studies might benefit from considering the possible social dimension of feeding behaviour.