Individual Differences In Behavior Research Articles

Oral microbiota in autistic children: Diagnosis-related differences and associations with clinical characteristics

Similar to the gut microbiome, oral microbiome compositions have been suggested to play an important role in the etiology of autism. However, empirical research on how variations in the oral microbiome relate to clinical-behavioral difficulties associated with autism remains sparse. Furthermore, it is largely unknown how potentially confounding lifestyle variables, such as oral health and nutrition, may impact these associations. To fill this gap, the current study examined diagnosis-related differences in oral microbiome composition between 80 school-aged autistic children (8–12 years; 64 boys, 16 girls) versus 40 age-matched typically developing peers (32 boys, 8 girls). In addition, associations with individual differences in social functioning (SRS-2), repetitive behavior (RBS-R) and anxiety (SCARED) were explored, as well as the impact of several lifestyle variables regarding nutrition and oral health. Results provide important indications that the bacterial genera Solobacterium, Stomatobaculum, Ruminococcaceae UCG.014, Tannerella and Campylobacter were significantly more abundant in autistic compared to non-autistic children. Furthermore, the former four bacteria that were significantly more abundant in the autistic children showed significant associations with parent-reported social difficulties, repetitive and restrictive behavior and with parent-reported anxiety-like behavior. Importantly, associations among oral microbiome and quantitative diagnostic characteristics were not significantly driven by differences in lifestyle variables. This exploratory study reveals significant differences in oral microbiome composition between autistic and non-autistic children, even while controlling for potential confounding lifestyle variables. Furthermore, the significant associations with clinical characteristics suggest that individual differences in microbiome composition might be involved in shaping the clinical phenotype of autism. However, these associations warrant further exploration of the oral microbiome's potential beyond the oral cavity and specifically with respect to neuropsychiatric conditions.

Prevalence and contributing factors of intestinal parasitic infections among school children with malnutrition in Hetauda, Nepal: A cross‐sectional study

AbstractBackground and AimsWith existing undernutrition in the developing world, the prevalence of obesity is increasing rapidly. Some studies reported an association of intestinal parasitic infection (IPIs) with undernutrition while few recent studies reported an inverse association of IPIs with overweight and obesity. This study evaluated the comparative risk and associated factors of IPIs among under (body mass index [BMI] < 18.5), normal (BMI: 18.5–24.9) and overweight (BMI > 24.9) school‐aged adolescents.MethodsA total of 105 fecal samples were collected, with 35 samples from each group. The collected samples were tested for the presence of intestinal parasites via concentration method, and the parasites were identified morphologically.ResultsOverall prevalence of IPIs was 5.71% with 3 protozoa viz Giardia lamblia (2.86%), Entamoeba histolytica (1.90%) and Endolimax nana (0.95%). Univariate and multivariable regression analysis indicated none of the nutritional, socioeconomic status, demographic, lifestyle and behavioral characteristics were significantly associated with the prevalence of overall IPIs. Yet, significant numbers of male reported undernutrition and elevated risk of IPIs in this study population.ConclusionDespite low prevalence of IPIs in this study, risk of IPIs is attributable to individual differences in behavior like “not using soap for hand washing”. Relatively elevated malnutrition with risky hygiene behaviors, male adolescents appeared as risky cluster of school age population.

Individual behavioural variation does not affect social organization or reproductive success in a cooperative small mammal

Abstract Recent evidence indicates that individual behavioural variation in animals, defined as consistent individual differences in behaviour across contexts and time, influence ecological and evolutionary processes, and a growing number of studies demonstrate that individual behavioural variation can play a large role in shaping grouping dynamics among social animals. We studied the common degu, Octodon degus, a social rodent, to evaluate whether individual behavioural variation underlies social organization and the reproductive success of individuals within groups. We examined social groups in a population in central-north Chile during one breeding season, tested 67 adults in an open field test (i.e., the propensity to explore an unfamiliar environment) and 62 adults in a poke test (i.e., the propensity to charge an object) to quantify individual behavioural variation, determined assortment based on individual behavioural differences across 19 social groups, and performed genetic analyses to assess reproductive success. We found that the response to the poke test was repeatable, while none of the behaviours from an open field test were. The repeatable behaviour during the poke test was not associated to components of social organization (group composition), or to reproductive success. These findings imply that individual behavioural variation did not affect grouping patterns or direct fitness in this degu population.

Human Milk Cannabinoid Concentrations and Associations with Maternal Factors: The Lactation and Cannabis (LAC) Study.

Background and Objectives: As cannabis use increases among reproductive-aged women, there is a growing need to better understand the presence of cannabinoids in milk produced by women using cannabis. It is unclear how concentrations of cannabinoids such as delta-9-tetrahydrocannabinol (Δ9-THC) persist in milk after cannabis use and what factors contribute to variation in milk Δ9-THC concentrations. Our objectives were to measure cannabinoids in human milk following cannabis abstention, after single and repeated instances of cannabis use, and identify factors contributing to concentration variation. Methods: The Lactation and Cannabis (LAC) Study prospectively observed 20 breastfeeding participants who frequently used cannabis (≥1/week), had enrolled <6 months postpartum, were feeding their infant their milk ≥5 times/day, and were not using any illicit drugs. Participants collected a baseline milk sample after ≥12 hours of abstaining from cannabis and five milk samples at set intervals over 8-12 hours after initial cannabis use. Participants completed surveys and recorded self-directed cannabis use during the study period. Results: Δ9-THC peaked 120 minutes after a single instance of cannabis use (median, n = 9). More instances of cannabis use during the study period were associated with greater Δ9-THC area-under-the-curve concentrations (ρ = 0.65, p = 0.002), indicating Δ9-THC bioaccumulation in most participants. Baseline Δ9-THC logged concentration was positively associated with self-reported frequency of cannabis use (b = 0.57, p = 0.01). Conclusions: Cannabinoids are measurable in human milk following cannabis use, and concentrations remain elevated with repeated cannabis use over a day. Substantial variation in Δ9-THC milk concentrations reflects individual differences in characteristics and behavior, including average postpartum frequency of cannabis use.

A rat model of operant negative reinforcement in opioid-dependent males and females.

Avoidance of opioid withdrawal plays a key role in human opioid addiction. Here, we present a procedure for studying operant negative reinforcement in rats that was inspired by primate procedures where opioid-dependent subjects lever-press to prevent naloxone infusions. In Experiment 1, we trained rats (n = 30, 15 females) to lever-press to escape and then avoid mild footshocks (0.13-0.27mA) for 35days (30 trials/d). Next, we catheterized them and implanted minipumps containing methadone (10mg/kg/day) or saline. We then paired (4 times, single session) a light cue (20-s) with a naloxone infusion (20µg/kg, i.v) that precipitated opioid withdrawal. Next, we trained the rats to escape naloxone injections for 10days (30 trials/d). Each trial started with the onset of the opioid-withdrawal cue. After 20-s, the lever extended, and an infusion of naloxone (1 to 2.2µg/kg/infusion) began; a lever-press during an 11-s window terminated the withdrawal-paired cue and the infusion. In Experiment 2, we trained rats (n = 34, 17 females) on the same procedure but decreased the footshock escape/avoidance training to 20days. All rats learned to lever-press to escape or avoid mild footshocks. In both experiments, a subset, 56% (10/18) and 33% (8/24) of methadone-dependent rats learned to lever-press to escape naloxone infusions. We introduce an operant negative reinforcement procedure where a subset of opioid-dependent rats learned to lever-press to escape withdrawal-inducing naloxone infusions. The procedure can be used to study mechanisms of individual differences in opioid negative reinforcement-related behaviors in opioid-dependent rats.

Exploring the comorbidity between internalizing/externalizing dimensions and cognitive disengagement syndrome through twin studies: a narrative review

Twin studies are cutting-edge design methodologies proper to behavioral genetics that aim to investigate how the interplay between genetic and environmental factors can concur to explain individual differences in psychopathology, temperamental traits, and behavior. This particular research design has been widely applied to the study of comorbidity between internalizing (INT) and externalizing (EXT) symptoms, especially in childhood and adolescence. Notably, the high co-occurrence of symptoms of both these diagnostic domains has led to the hypothesis that at their basis, there might be one single latent common susceptibility factor, namely p factor. Twin studies have contributed to marking a relevant turning point in this regard by highlighting the consistent genetic nature of this factor. In light of these premises, the present narrative review aims to outline the path for future twin studies in investigating the comorbidity between Cognitive Disengagement Syndrome (CDS) and INT-EXT disorders, examining the evidence supporting this need and its clinical implications. Since CDS has not been recognized as a stand-alone syndrome until very recently, research on this condition is still in its infancy and the etiological factors at the basis of its comorbidity with INT-EXT are still unclear. Being aware of the causal factors underneath the comorbidity between INT-EXT might pave the way for improving assessment diagnostic procedures as well as setting up preventive interventions for CDS.

Do sexes differ in consistent individual differences and behavioural syndrome in an aposematic poison frog?

AbstractThere is a burgeoning interest in studying consistent individual differences in animal behaviour. Most studies consider mainly males, but sexes are subject to distinct selection pressures that may drive differences in life history and therefore lead to differences in a variety of behaviours. Here, we used Oophaga pumilio, a poison frog with sex differences in life‐history strategies (e.g., sex bias in space use and parental care), to explore whether sexes differ or share personality characteristics like behavioural consistency and behavioural syndromes. Based on the natural history of this species, we predicted sex differences in behavioural consistency in exploration but not in boldness, and a correlation between these behavioural traits. We found no sex differences in behavioural consistency in boldness and exploration, although, we observed a tendency of higher consistency in males than females in boldness. When pooling all individuals, we found a higher consistency in boldness than exploration, suggesting the presence of a bold personality in general. We observed a positive between‐individual correlation of boldness and exploration in both sexes indicating the presence of a behavioural syndrome. Our data suggest that selective mechanisms shaping individual behaviour act equally on both sexes in this poison frog.

Psychographic segmentation of multichannel customers: investigating the influence of individual differences on channel choice and switching behavior

This study investigates the role of individual differences in channel choice and switching behavior in a multichannel environment using latent class analysis on data from 1512 customers. Psychographic variables from five domains (risk attitudes, cognitive ability, motivation, personality, and decision-making style) serve as covariates for multichannel customer behavior. We identify six segments that differ significantly on six psychographic variables (readiness to take risks, need for cognition, autotelic and instrumental need for touch, and rational and intuitive decision-making styles). The results advance the theory-building of multichannel customer behavior and present insights for proactively managing customer journeys of distinct segments.

Neurogenomic landscape associated with status-dependent cooperative behaviour.

The neurogenomic mechanisms mediating male-male reproductive cooperative behaviours remain unknown. We leveraged extensive transcriptomic and behavioural data on a neotropical bird species (Pipra filicauda) that performs cooperative courtship displays to understand these mechanisms. In this species, the cooperative display is modulated by testosterone, which promotes cooperation in non-territorial birds, but suppresses cooperation in territory holders. We sought to understand the neurogenomic underpinnings of three related traits: social status, cooperative display behaviour and testosterone phenotype. To do this, we profiled gene expression in 10 brain nuclei spanning the social decision-making network (SDMN), and two key endocrine tissues that regulate social behaviour. We associated gene expression with each bird's behavioural and endocrine profile derived from 3 years of repeated measures taken from free-living birds in the Ecuadorian Amazon. We found distinct landscapes of constitutive gene expression were associated with social status, testosterone phenotype and cooperation, reflecting the modular organization and engagement of neuroendocrine tissues. Sex-steroid and neuropeptide signalling appeared to be important in mediating status-specific relationships between testosterone and cooperation, suggesting shared regulatory mechanisms with male aggressive and sexual behaviours. We also identified differentially regulated genes involved in cellular activity and synaptic potentiation, suggesting multiple mechanisms underpin these genomic states. Finally, we identified SDMN-wide gene expression differences between territorial and floater males that could form the basis of 'status-specific' neurophysiological phenotypes, potentially mediated by testosterone and growth hormone. Overall, our findings provide new, systems-level insights into the mechanisms of cooperative behaviour and suggest that differences in neurogenomic state are the basis for individual differences in social behaviour.

Social Defeat Stress Model for Adolescent C57BL/6 Male and Female Mice.

Social adversity in adolescence is prevalent and can negatively impact mental health trajectories. Modeling social stress in adolescent male and female rodents is needed to understand its effects on ongoing brain development and behavioral outcomes. The chronic social defeat stress paradigm (CSDS) has been widely used to model social stress in adult C57BL/6 male mice by leveraging on the aggressive behavior displayed by an adult male rodent to an intruder invading its territory. An advantage of this paradigm is that it allows to categorize defeated mice into resilient and susceptible groups based on their individual differences in social behavior 24 h after the last defeat session. Implementing this model in adolescent C57BL/6 mice has been challenging because adult or adolescent mice do not typically attack early adolescent male or female mice and because adolescence is a short period of life, encompassing discreet temporal windows of vulnerability. This limitation was overcome by adapting an accelerated version of the CSDS to be used for adolescent male and female mice. This 4-day stress paradigm with 2 physical attack sessions per day uses a C57BL/6 male adult to prime the CD-1 mouse for aggressiveness such that it readily attacks the male or female adolescent mouse. This model was termed accelerated social defeat stress (AcSD) for adolescent mice. Adolescent exposure to AcSD induces social avoidance 24 h later in both males and females, but only in a subset of defeated mice. This vulnerability occurs despite the number of attacks being consistent across sessions between resilient and susceptible groups. The AcSD model is short enough to allow exposure during discrete periods within adolescence, allows the segregation of mice according to the presence or absence of social avoidance behavior, and is the first model available to study social defeat stress in adolescent C57BL/6 female mice.

Individual differences in human gaze behavior generalize from faces to objects

Individuals differ in where they fixate on a face, with some looking closer to the eyes while others prefer the mouth region. These individual biases are highly robust, generalize from the lab to the outside world, and have been associated with social cognition and associated disorders. However, it is unclear, whether these biases are specific to faces or influenced by domain-general mechanisms of vision. Here, we juxtaposed these hypotheses by testing whether individual face fixation biases generalize to inanimate objects. We analyzed >1.8 million fixations toward faces and objects in complex natural scenes from 405 participants tested in multiple labs. Consistent interindividual differences in fixation positions were highly inter-correlated across faces and objects in all samples. Observers who fixated closer to the eye region also fixated higher on inanimate objects and vice versa. Furthermore, the inter-individual spread of fixation positions scaled with target size in precisely the same, non-linear manner for faces and objects. These findings contradict a purely domain-specific account of individual face gaze. Instead, they suggest significant domain-general contributions to the individual way we look at faces, a finding with potential relevance for basic vision, face perception, social cognition, and associated clinical conditions.

Improving Individual Innovative Behavior and Post-COVID-19 Student’ Learning Outcomes Through Project-Based Blended Learning

Objective: This study aims to improve individual innovative behavior and learning outcomes and determine differences in individual innovative behavior and student learning outcomes after being taught with Project_Based Blended Learning synchronous and asynchronous online models followed by face-to-face offline models in the post-COVID-19 era. Method: The research used a quasi-experiment; the control class samples were 33, and the experimental class was 33 students. Data were collected using questionnaires, test instruments, and observation sheets, and the collected data were analyzed using descriptive statistics, gain tests, and t-tests. Result: The increase in individual innovative behavior and learning outcomes before and after teaching in the control class in the moderately effective category is lower and significantly different compared to the experimental class in the practical category. The final score of individual innovative behavior and learning outcomes of the control class is lower and significantly different than that of the experimental class. Novelty: Blended Learning in this research is integrated with Project-Based Learning with synchronous and asynchronous online models to produce project products assigned to be used in practical courses.

Why moral psychology needs personality psychology.

People vary in how they perceive, think about, and respond to moral issues. Clearly, we cannot fully understand the psychology of morality without accounting for individual differences in moral functioning. But decades of neglect of and explicit skepticism toward such individual differences has resulted in a lack of integration between moral psychology and personality psychology-the study of psychological differences between people. In recent years, these barriers to progress have started to break down. This special issue aims to celebrate and further increase the visibility of the personality psychology of morality. Here, we introduce the articles in this special issue by highlighting some important contributions a personality-based perspective has to offer moral psychology-particularly in comparison to the currently prominent social psychological approach. We show that personality psychology is well-placed to (a) contribute toward a rigorous empirical foundation for moral psychology, (b) tackle the conceptualization and assessment of stable moral tendencies, (c) assess the predictive validity of moral traits in relation to consequential outcomes, (d) uncover the mechanisms underlying individual differences in moral judgments and behavior, and (e) provide insights into moral development. For these reasons, we believe that moral psychology needs personality psychology to reach its full scholarly potential.

Bolder together: conformity drives behavioral plasticity in eastern gartersnakes

Personality traits drive individual differences in behaviour that are consistent across time and context. Personality limits behavioural plasticity, which could lead to maladaptive choices if animals cannot adapt their behavior to changing conditions. Here, we assessed consistency and flexibility in one personality trait, boldness, across non-social and social contexts in eastern gartersnakes (Thamnophis sirtalis sirtalis). Snakes explored a novel open arena either alone or in a pair. Pairs were assigned based on the data from the solo trials, such that each snake was paired once with a bolder and once with a less bold partner. We predicted that snakes would conform when in a social context, displaying plasticity in their personality, and causing boldness scores to converge. We found that snakes were consistent within contexts (solo or paired), but changed their behavior across contexts (from solo to paired). Plasticity in boldness resulted from an interaction between conformity and repeatable individual differences in plasticity. In line with some data on other species, snakes conformed more when they were the less bold partner. Personality reflects a consistent bias in decision-making, but our results highlight that the cognitive processes that drive the expression of personality traits in behavior are flexible and sensitive to social context. We show that both consistency and plasticity combine to shape snake social behavior in ways that are responsive to competition. This pattern of behavior may be particularly beneficial for species in which group-living is seasonal.

Exploring deep learning techniques for wild animal behaviour classification using animal‐borne accelerometers

Abstract Machine learning‐based behaviour classification using acceleration data is a powerful tool in bio‐logging research. Deep learning architectures such as convolutional neural networks (CNN), long short‐term memory (LSTM) and self‐attention mechanism as well as related training techniques have been extensively studied in human activity recognition. However, they have rarely been used in wild animal studies. The main challenges of acceleration‐based wild animal behaviour classification include data shortages, class imbalance problems, various types of noise in data due to differences in individual behaviour and where the loggers were attached and complexity in data due to complex animal‐specific behaviours, which may have limited the application of deep learning techniques in this area. To overcome these challenges, we explored the effectiveness of techniques for efficient model training: data augmentation, manifold mixup and pre‐training of deep learning models with unlabelled data, using datasets from two species of wild seabirds and state‐of‐the‐art deep learning model architectures. Data augmentation improved the overall model performance when one of the various techniques (none, scaling, jittering, permutation, time‐warping and rotation) was randomly applied to each data during mini‐batch training. Manifold mixup also improved model performance, but not as much as random data augmentation. Pre‐training with unlabelled data did not improve model performance. The state‐of‐the‐art deep learning models, including a model consisting of four CNN layers, an LSTM layer and a multi‐head attention layer, as well as its modified version with shortcut connection, showed better performance among other comparative models. Using only raw acceleration data as inputs, these models outperformed classic machine learning approaches that used 119 handcrafted features. Our experiments showed that deep learning techniques are promising for acceleration‐based behaviour classification of wild animals and highlighted some challenges (e.g. effective use of unlabelled data). There is scope for greater exploration of deep learning techniques in wild animal studies (e.g. advanced data augmentation, multimodal sensor data use, transfer learning and self‐supervised learning). We hope that this study will stimulate the development of deep learning techniques for wild animal behaviour classification using time‐series sensor data.

THE HORSE BEHAVIOR TOWARD GROOMING

The domestication and selective breeding of horses for various purposes have led to the emergence of distinct horse breeds, often associated with specific physical traits and behavioral tendencies. Understanding individual differences in horse behavior, particularly during interactions with humans, is essential for promoting positive experiences and welfare. Mane grooming, a common human-horse interaction, provides valuable insights into horse emotional responses and preferences. This study investigates the behaviors of seven distinct horse breeds during mane grooming sessions through real-world observations. It aims to gain insights into horses' emotional responses, focusing on approach and avoidance behaviors, and explores potential influences on their reactions towards grooming, such as gender, mane direction, and breed characteristics. Results reveal personality differences among the seven horse breeds, with only 10.28% exhibiting aggressive behaviors during grooming. Mane direction in horses is primarily determined by genetics, with most having left or right manes. Some variations were observed among breeds, but differences were not substantial. Overall, this research highlights the importance of considering individual and breed-specific traits in mane grooming practices to enhance horse welfare and strengthen the human-horse bond.

Sustained looking at faces at 5months of age is associated with socio-communicative skills in the second year of life.

Efficiently processing information from faces in infancy is foundational for nonverbal communication. We studied individual differences in 5-month-old infants' (N=517) sustained attention to faces and preference for emotional faces. We assessed the contribution of genetic and environmental influences to individual differences in these gaze behaviors, and the association between these traits and other concurrent and later phenotypes. We found an association between the mean duration of looking at a face (before looking away from it) at 5months and socio-communicative abilities at 14months (β=0.17, 95% CI: 0.08; 0.26, p<0.001). Sustained attention to faces predicted socio-communicative abilities over and above variance captured by mean fixation duration. We also found a statistically significant but weak tendency to prefer looking at smiling faces (relative to neutral faces), but no indication that variability in this behavior was explained by genetic effects. Moderate heritability was found for sustained attention to faces (A=0.23, CI: 0.06; 0.38), while shared environmental influences were non-significant for both phenotypes. These findings suggest that sustained looking at individual faces before looking away is a developmentally significant 'social attention' phenotype in infancy, characterized by moderate heritability and a specific relation to later socio-communicative abilities.

Personality and Individual Differences in Leadership Behavior. Α Review

The study of personality and individual variations in leadership conduct is an intricate and multifaceted domain that has attracted substantial interest in organizational psychology and leadership studies. This review examines the complex correlation between personality traits and individual variations and their effect on leadership conduct. It encompasses diverse aspects such as servant leadership, transformational leadership, and shared leadership, as well as the influence of gender and cultural factors. A thorough comprehension of the intricate aspects of personality and individual differences in leadership behavior is essential to understanding how these factors interact with different leadership styles, organizational contexts, and cultural dynamics. This abstract introduces the complex connection between personality and individual differences in influencing leadership behavior. It paves the way for a more thorough examination of the challenges and perspectives related to this relationship.

Investigating the Roles of the Visual and Parietal Cortex in Representing Content versus Context in Visual Working Memory.

Content-to-context binding is crucial for working memory performance. Using a dual-serial retrocueing (DSR) task on oriented gratings, Yu et al. (2020) found that content (orientation) of both prioritized and unprioritized memory items (PMI; UMI) was represented simultaneously in visual cortex, while their context (location) was represented in intraparietal sulcus (IPS), with a priority-based remapping of the representation of content and context of the UMI in each region, respectively. This registered report acquired fMRI of 24 healthy adults while they performed a DSR task with location as the to-be-reported content and orientation as the task-relevant context. We contrasted three accounts: domain-dependent, the engagement of visual and parietal regions depends on the feature domain (orientation vs location); functional, the engagement of these regions depends on their function (content vs context); and hybrid-a combination of the domain-dependent account and the additional stipulation that IPS encodes context regardless of domain. Delay-period activity in early visual cortex conformed most closely with functional predictions: robust priority-sensitive representation of stimulus location (content), but no evidence for the active representation of stimulus orientation (context). Delay-period activity in IPS, in contrast, conformed most closely to predictions of the hybrid account: active representation of content (location) and of prioritized context (orientation). Exploratory analyses further supported the hybrid account of IPS, revealing univariate sensitivity to variation in both content and context load, the latter in a manner that predicted individual differences in behavior. The representation of visual information in working memory is highly dependent on behavioral context.

Humanized dopamine D4.7 receptor male mice display risk-taking behavior and deficits of social recognition and working memory in light/dark-dependent manner.

The dopamine D4 receptor 7-repeat allele (D4.7 R) has been linked with psychiatric disorders such as attention-deficit-hyperactivity disorder, autism, and schizophrenia. However, the highly diverse study populations and often contradictory findings make it difficult to draw reliable conclusions. The D4.7 R has the potential to explain individual differences in behavior. However, there is still a great deal of ambiguity surrounding whether it is causally connected to the etiology of psychiatric disorders. Therefore, humanized D4.7 R mice, with the long third intracellular domain of the human D4.7 R, may provide a valuable tool to examine the relationship between the D4.7 R variant and specific behavioral phenotypes. We report that D4.7 R male mice carrying the humanized D4.7 R variant exhibit distinct behavioral features that are dependent on the light-dark cycle. The behavioral phenotype was characterized by a working memory deficit, delayed decision execution in the light phase, decreased stress and anxiety, and increased risk behavior in the dark phase. Further, D4.7 R mice displayed impaired social recognition memory in both the light and dark phases. These findings provide insight into the potential causal relationship between the human D4.7 R variant and specific behaviors and encourage further consideration of dopamine D4 receptor (DRD4) ligands as novel treatments for psychiatric disorders in which D4.7 R has been implicated.