Painful Experiences in Social Contexts Facilitate Sensitivity to Emotional Signals of Pain from Conspecifics in Laboratory Rats.

Previous studies demonstrated that laboratory rats could visually receive emotional pain signals from conspecifics through pictorial stimuli. The present study examined whether a prior painful emotional experience of the receiver influenced the sensitivity of emotional expression recognition in laboratory rats. The experiment comprised four phases: the baseline preference test, pain manipulation test, post-manipulation preference test, and state anxiety test. In the baseline phase, the rats explored an apparatus comprising two boxes to which pictures of pain or neutral expressions of other conspecifics were attached. In the pain manipulation phase, each rat was allocated to one of three conditions: foot shock alone (pained-alone; PA), foot shock with other unfamiliar conspecifics (pained-with-other; PWO), or no foot shock (control). In the post-manipulation phase, the animals explored the apparatus in the same manner as they did in the baseline phase. Finally, an open-field test was used to measure state anxiety. These findings indicate that rats in the PWO group stayed longer per entry in a box with photographs depicting a neutral disposition than in a box with photographs depicting pain after manipulation. The results of the open-field test showed no significant differences between the groups, suggesting that the increased sensitivity to pain expression in other individuals due to pain experiences in social settings was not due to increased primary state anxiety. Furthermore, the results indicate that rats may use a combination of self-painful experiences and the states of other conspecifics to process the emotional signal of pain from other conspecifics. In addition, changes in the responses of rats to facial expressions in accordance with social experience suggest that the expression function of rats is not only used for emotional expressions but also for communication.

Developmental changes in neonatal hemodynamics during tactile stimulation using whole-head functional near-infrared spectroscopy.

Neural-activity-associated hemodynamic changes have been used to noninvasively measure brain function in the early developmental stages. However, the temporal changes in their hemodynamics are not always consistent with adults. Studies have not evaluated developmental changes for a long period using the same stimuli; therefore, this study examined the normalized relative changes in oxygenated hemoglobin (Δ[oxy-Hb]) in full-term infants and compared them with neonates up to 10 months of age during the administration of tactile vibration stimuli to their limbs using whole-head functional near-infrared spectroscopy. The time to peak of normalized Δ[oxy-Hb] was not affected by age. The amplitude of normalized Δ[oxy-Hb] showed an effect of age in broader areas, including sensorimotor-related but excluding supplementary motor area; the amplitude of normalized Δ[oxy-Hb] decreased the most in the 1-2-month-old group and later increased with development. We hypothesized that these results may reflect developmental changes in neural activity, vasculature, and blood oxygenation.

Tohoku Medical Megabank Brain Magnetic Resonance Imaging Study: Rationale, Design, and Background.

The Tohoku Medical Megabank Brain Magnetic Resonance Imaging Study (TMM Brain MRI Study) was established to collect multimodal information through neuroimaging and neuropsychological assessments to evaluate the cognitive function and mental health of residents who experienced the Great East Japan Earthquake (GEJE) and associated tsunami. The study also aimed to promote advances in personalized healthcare and medicine related to mental health and cognitive function among the general population. We recruited participants for the first (baseline) survey starting in July 2014, enrolling individuals who were participating in either the TMM Community-Based Cohort Study (TMM CommCohort Study) or the TMM Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study). We collected multiple magnetic resonance imaging (MRI) sequences, including 3D T1-weighted sequences, magnetic resonance angiography (MRA), diffusion tensor imaging (DTI), pseudo-continuous arterial spin labeling (pCASL), and three-dimensional fluid-attenuated inversion recovery (FLAIR) sequences. To assess neuropsychological status, we used both questionnaire- and interview-based rating scales. The former assessments included the Tri-axial Coping Scale, Impact of Event Scale in Japanese, Profile of Mood States, and 15-item Depression, Anxiety, and Stress Scale, whereas the latter assessments included the Mini-Mental State Examination, Japanese version. A total of 12,164 individuals were recruited for the first (baseline) survey, including those unable to complete all assessments. In parallel, we returned the MRI results to the participants and subsequently shared the MRI data through the TMM Biobank. At present, the second (first follow-up) survey of the study started in October 2019 is underway. In this study, we established a large and comprehensive database that included robust neuroimaging data as well as psychological and cognitive assessment data. In combination with genomic and omics data already contained in the TMM Biobank database, these data could provide new insights into the relationships of pathological processes with neuropsychological disorders, including age-related cognitive impairment.

Imagine distant-future outcome: Mental simulation of COVID-19 vaccinations.

The COVID-19 pandemic is a global public health crisis. Although it has been expected that the vaccination of COVID-19 mitigates the crisis, some people are reluctant to receive the COVID-19 vaccination. Based on the theory of mental simulation and affective forecasting, we investigated how mental simulations influence COVID-19 vaccination intention. Three preregistered experiments were conducted (total n = 970). Experiment 1 tested for whether outcome (vs. process) simulation would increase COVID-19 vaccination intention. Experiment 2 explored whether temporal proximity of simulations (distant-future outcome, near-future outcome, process) modulate the effects of mental simulation on expected emotion and COVID-19 vaccination intention. Experiment 3 examined the role of the number of sensory modalities (multisensory, unisensory) in mental simulations. The result of Experiment 1 (n = 271) demonstrated that outcome (vs. process) simulation of the COVID-19 vaccination led to greater COVID-19 vaccination intention. The result of Experiment 2 (n = 227) revealed that distant-future outcome simulation (vs. near-future outcome simulation, process simulation) increased expected positivity and then enhanced COVID-19 vaccination intention. The result of Experiment 3 (n = 472) also demonstrated that distant-future outcome simulation (vs. near-future outcome simulation, process simulation) increased expected positivity and then enhanced COVID-19 vaccination intention regardless of the number of sensory modalities to be simulated. Our findings reveal how mental simulations influence COVID-19 vaccination intention and provide practical implications for effective health communication strategies for the COVID-19 vaccination intention. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Cultural differences in recognizing emotions of masked faces.

In the wake of the global pandemic, interacting with others while wearing masks has emerged as a global challenge. A growing body of literature has reported that face masks hinder emotion recognition in Western populations. Given that diagnostic facial features for recognizing specific emotions (e.g., happiness) differ between Western and Eastern cultures, there may be cultural differences in the effects of face masks on emotion recognition. Relying on the previous findings showing cultural differences in emotion recognition, we conducted a preregistered study where 203 American and 209 Japanese participants judged the emotional expressions of faces (happy, fearful, angry, sad, disgust, and neutral) with and without masks. The results showed cultural differences in emotion recognition of faces with and without masks. Specifically, face masks decreased the accuracy of happy emotion recognition in the Americans but not in the Japanese. The results suggest that the effect of wearing masks on emotion recognition depends on the types of emotions and culture and supports previous findings indicating cultural differences in the decoding strategy for facial expressions. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Higher-resolution quantification of white matter hypointensities by large-scale transfer learning from 2D images on the JPSC-AD cohort.

White matter lesions (WML) commonly occur in older brains and are quantifiable on MRI, often used as a biomarker in Aging research. Although algorithms are regularly proposed that identify these lesions from T2-fluid-attenuated inversion recovery (FLAIR) sequences, none so far can estimate lesions directly from T1-weighted images with acceptable accuracy. Since 3D T1 is a polyvalent and higher-resolution sequence, it could be beneficial to obtain the distribution of WML directly from it. However a serious difficulty, both for algorithms and human, can be found in the ambiguities of brain signal intensity in T1 images. This manuscript shows that a cross-domain ConvNet (Convolutional Neural Network) approach can help solve this problem. Still, this is non-trivial, as it would appear to require a large and varied dataset (for robustness) labelled at the same high resolution (for spatial accuracy). Instead, our model was taught from two-dimensional FLAIR images with a loss function designed to handle the super-resolution need. And crucially, we leveraged a very large training set for this task, the recently assembled, multi-sites Japan Prospective Studies Collaboration for Aging and Dementia (JPSC-AD) cohort. We describe the two-step procedure that we followed to handle such a large number of imperfectly labeled samples. A large-scale accuracy evaluation conducted against FreeSurfer 7, and a further visual expert rating revealed that WML segmentation from our ConvNet was consistently better. Finally, we made a directly usable software program based on that trained ConvNet model, available at https://github.com/bthyreau/deep-T1-WMH.

Altruistic Social Activity, Depressive Symptoms, and Brain Regional Gray Matter Volume: Voxel-Based Morphometry Analysis From 8,695 Old Adults.

Altruistic social activity, such as giving support to others, has shown protective benefits on dementia risk and cognitive decline. However, the pathological mechanism is unclear. In the present study, we investigated the association between altruistic social activity and brain regional gray matter. Furthermore, to explore the psychological interplay in altruistic social activity, we tested mediating effect of depressive symptoms on brain regional gray matter. We performed a cross-sectional voxel-based morphology (VBM) analysis including 8 695 old adults (72.9 ± 6.1 years) from Japan Prospective Studies Collaboration for Aging and Dementia (JPSC-AD) Cohort. We measured altruistic social activities by self-report questionnaires, depressive symptoms by Geriatric Depression Scale (GDS)-short version. We employed the whole-brain VBM method to detect relevant structural properties related to altruistic social activity. We then performed multiple regression models to detect the mediating effect of depressive symptoms on particular brain regional gray matter volume while adjusting possible physical and social lifestyle covariables. We found that altruistic social activity is associated with larger gray matter volume in posterior insula, middle cingulate gyrus, hippocampus, thalamus, superior temporal gyrus, anterior orbital gyrus, and middle occipital gyrus. Depressive symptoms mediated over 10% on altruistic social activity and hippocampus volume, over 20% on altruistic social activity and cingulate gyrus volume. Our results indicated that altruistic social activity might preserve brain regional gray matter which are sensitive to aging and cognitive decline. Meanwhile, this association may be explained by indirect effect on depressive symptoms, suggesting that altruistic social activity may mitigate the neuropathology of dementia.

Effect of the Intake of Brown Rice for Six Months on the Cognitive Function in Healthy Elderly Persons: A Study Protocol for a Pilot, Non-Randomized Controlled Trial.

The nutritional components of brown rice have been reported to be effective against diabetes mellitus. Recent animal studies have suggested that it is also effective in maintaining cognitive function. Therefore, in this study, we examined the effect of a brown rice diet on cognitive function in individuals aged over 60 years. The study participants were recruited from a pool of individuals aged ≥60 years who were using elderly care facilities. The participants were provided with four servings of brown or white rice per week for 6 months, and their cognitive function was measured before and after the intervention period. Prior to the intervention, participants tasted the white and brown rice to determine which type they would like to be offered over the 6-month period. Since rice is the staple food of the participants in this study, they were allowed to decide whether they wanted to eat white or brown rice.

The Role of Temperature in Moral Decision-Making: Limited Reproducibility.

Temperature is one of the major environmental factors that people are exposed to on a daily basis, often in conditions that do not afford control. It is known that heat and cold can influence a person's productivity and performance in simple tasks. With respect to social cognition, it has also been suggested that temperature impacts on relatively high-level forms of decision-making. For instance, previous research demonstrated that cold temperature promotes utilitarian judgment in a moral dilemma task. This effect could be due to psychological processing, when a cool temperature primes a set of internal representations (associated with "coldness"). Alternatively, the promotion of utilitarian judgment in cold conditions could be due to physiological interference from temperature, impeding on social cognition. Refuting both explanations of psychological or physiological processing, however, it has been suggested that there may be problems of reproducibility in the literature on temperature modulating complex or abstract information processing. To examine the role of temperature in moral decision-making, we conducted a series of experiments using ambient and haptic temperature with careful manipulation checks and modified task methodology. Experiment 1 manipulated room temperature with cool (21°C), control (24°C) and hot (27°C) conditions and found only a cool temperature effect, promoting utilitarian judgment as in the previous study. Experiment 2 manipulated the intensity of haptic temperature but failed to obtain the cool temperature effect. Experiments 3 and 4 examined the generalizability of the cool ambient temperature effect with another moral judgment task and with manipulation of exposure duration. However, again there were no cool temperature effects, suggesting a lack of reproducibility. Despite successful manipulations of temperature in all four experiments, as measured in body temperature and the participants' self-reported perception, we found no systematic influence of temperature on moral decision-making. A Bayesian meta-analysis of the four experiments showed that the overall data tended to provide strong support in favor of the null hypothesis. We propose that, at least in the range of temperatures from 21 to 27°C, the cool temperature effect in moral decision-making is not a robust phenomenon.

Effects of Natural Reduced Water on Cognitive Function, Body Composition, and Psychological Function in Older Adults: Study Protocol for a Randomized Controlled Trial.

Natural reduced water is natural water that contains active hydrogen and reduces oxidation. It is rare in the world, and in Japan, it is produced in the Hita area of Oita Prefecture (Hita Tenryosui water). Previous studies in humans have examined the effects of natural reduced water on diabetes, which is one of the known risks for dementia. Animal studies of natural reduced water have revealed anti-obesity and anti-anxiety effects. However, the effects of natural reduced water on cognitive function, body composition, and psychological function in humans are unknown. Therefore, we investigated the relationship between these items in elderly people who continuously consume natural reduced water. In this study, we recruited participants aged between 65 and 74 years. The participants were randomly and blindly assigned to a natural reduced water (Hita Tenryosui water) group or a control (tap water) group and drank 1 L of water daily for 6 months. Cognitive function, body composition, and psychological function were measured before and after the 6-month intervention period.

Dataset of reaching behavior for reward in social situations in mice.

The data presented in this article is from a paper entitled "An experimental task to examine the mirror neuron system in mice: Laboratory mice understand the movement intentions of other mice based on their own experience" (Ukezono and Takano, 2021). This article contains individual data on reaching behavior for reward in social situations in mice. In the reaching room, the mice first learned how to acquire food by reaching their limbs. The mice that had learned reaching were placed in an observation room where they could observe the reaching activity of another mouse in the reaching room. The data includes all animals' properties and conditions, the pairing state of another mouse (cage mate or non-cage mate), and a set of behavioral analyses. Our data have the potential to be reused for analyzing interaction behaviors of mice placed in front of rewards and developing experiments for behavioral neuroscience research on the mirror neuron system in mice.

An experimental task to examine the mirror neuron system in mice: Laboratory mice understand the movement intentions of other mice based on their own experience.

We developed a behavioral experiment to elucidate the neural mechanisms of intention understanding in mice. In this experiment, the mouse is first trained to acquire food by reaching with its forelimb. The mice that learnt this were placed in an experimental box wherein they can observe the reaching activity of another mouse. We found that trained mice tend to observe the reaching activity of other mice; mice that did not receive any prior training displayed a lower tendency towards observing another mouse's reaching behavior. In experiment 2, in order to rule out that observing the behaviors of other mice is solely due to interest in the feeding table or the social stimulus itself, we compared exploratory approach behaviors when the box with the feeding table was empty, when the untrained mouse did not reach it, and when another learnt mouse was reaching for the food. The results showed that exploratory approach behaviors to trained mice lasted significantly longer than the exploratory approach behavior to the empty box and untrained individuals. These results suggest that the learning of individuals' exploration of other reaching individuals may be motivated not only by interest in the presence of the feeding table and other individuals themselves, but also by an associated intentional movement. The tasks developed in our study could be used in the research of the mirror system in behavioral neuroscience to elucidate the mechanism underlying the ability of mice to understand the intent of other mice via motor learning.

Walking and talking independently predict interpersonal impressions.

When walking alongside someone, you may feel that your legs move in synchrony with theirs. Recent studies have shown that walk-in-synch behaviour observed in natural settings occurs at a rate significantly greater than would be expected by chance, and that the amount of this synchrony is related to interpersonal impressions. However, in such natural settings, the existence of verbal conversations between paired walkers should affect the interpersonal impressions and the effect is not distinguished from the effect of walk-in-synch on the impressions so far. In the current study, we used the analysis of conversation and path analysis to discriminate these two effects (i.e., the effects of synchronization of walking and conversation on interpersonal impressions). Analysis of conversation during the walk revealed that the amount of utterance overlap and the number of turn-takings between two walkers as well as the synchronization of steps predicted their positive interpersonal impression, while synchronization of steps and these two conversational indices were not correlated with each other. We propose that interpersonal synchronization of body movements, such as synchronization of steps itself in paired walking, plays a role in fostering the development of interpersonal relationships.

Ethnicity-Dependent Effects of Schizophrenia Risk Variants of the OLIG2 Gene on OLIG2 Transcription and White Matter Integrity.

Previous studies have indicated associations between several OLIG2 gene single-nucleotide polymorphisms (SNPs) and susceptibility to schizophrenia among Caucasians. Consistent with these findings, postmortem brain and diffusion tensor imaging studies have indicated that the schizophrenia-risk-associated allele (A) in the OLIG2 SNP rs1059004 predicts lower OLIG2 gene expression in the dorsolateral prefrontal cortex (DLPFC) of schizophrenia patients and reduced white matter (WM) integrity of the corona radiata in normal brains among Caucasians. In an effort to replicate the association between this variant and WM integrity among healthy Japanese, we found that the number of A alleles was positively correlated with WM integrity in some fiber tracts, including the right posterior limb of the internal capsule, and with mean blood flow in a widespread area, including the inferior frontal operculum, orbital area, and triangular gyrus. Because the A allele affected WM integrity in opposite directions in Japanese and Caucasians, we investigated a possible association between the OLIG2 gene SNPs and the expression level of OLIG2 transcripts in postmortem DLPFCs. We evaluated rs1059004 and additional SNPs in the 5' upstream and 3' downstream regions of rs1059004 to cover the broader region of the OLIG2 gene. The 2 SNPs (rs1059004 and rs9653711) had opposite effects on OLIG2 gene expression in the DLPFC in Japanese and Caucasians. These findings suggest ethnicity-dependent opposite effects of OLIG2 gene SNPs on WM integrity and OLIG2 gene expression in the brain, which may partially explain the failures in replicating associations between genetic variants and psychiatric phenotypes among ethnicities.

Object Categorization Processing Differs According to Category Level: Comparing Visual Information Between the Basic and Superordinate Levels.

Object category levels comprise a crucial concept in the field of object recognition. Specifically, categorization performance differs according to the category level of the target object. This study involved experiments with two types of stimulus sequences (i.e., forward condition: presenting the target name before the line-drawing stimulus; and reverse condition: presenting the target name after the line-drawing stimulus) for both basic- and superordinate-level categorizations. Adult participants were assigned to each level and asked to judge whether briefly presented stimuli included the same object and target name. Here, we investigated how the category level altered the categorization process. We conducted path analyses using a multivariate multiple regression model, and set our variables to investigate whether the predictors affected the categorization process between two types of stimulus sequence. Dependent variables included the measures of performance (i.e., reaction time, accuracy) for each categorization task. The predictors included dimensions and shapes of the line-drawings, such as primary and local shape information, shape complexity, subject estimation, and other shape variables related to object recognition. Results showed that the categorization process differed according to shape properties between conditions only for basic-level categorizations. For the forward condition, the bottom-up processing of primary visual information depended on matches with stored representations for the basic-level category. For the reverse condition at the basic-level category, decisions depended on subjective ratings in terms of object-representation accessibility. Finally, superordinate-level decisions depended on higher levels of visual information in terms of complexity, regardless of the condition. Thus, the given category level altered the processing of visual information for object recognition in relation to shape properties. This indicates that decision processing for object recognition is flexible depending on the criteria of the processed objects (e.g., category levels).

The gaze bias effect in toddlers: Preliminary evidence for the developmental study of visual decision-making.

Several studies have investigated the interactive relationship between attention and decision-making, which is known as the gaze bias effect. Although the generalizability of the gaze bias effect has recently been observed among young and older adults, it remains unknown in which developmental period individuals start to exhibit this relationship. This question was addressed in the current study by recruiting 58 toddlers aged 2-4 years. Participants were asked to do a two-alternative forced-choice task in which they chose one of two soft toys they preferred while their eye movements were recorded. Results demonstrated that toddlers exhibited gaze bias regardless of age. We also found that the number of gaze shifts during the task increased according to age. These results suggest that the interactive relationship between attention and decision is acquired by the age of two. The implications of the increased number of gaze shifts for visual decision-making are discussed.

Learning of efficient behaviour in spatial exploration through observation of behaviour of conspecific in laboratory rats.

Recent studies have suggested that rodent behaviour is influenced by the behaviour of surrounding conspecifics (e.g. emotional contagion and prosocial behaviour). However, little is known about deferred imitation and complex observational learning in rats. The purpose of this study was to reveal whether rats can learn from another rat's experiences. In a maze, observer rats watched the foraging behaviour of other rats (demonstrators) and then foraged in turn. The results showed that demonstrators explored inefficiently, but observers explored more efficiently after observing inefficient exploration by the demonstrators. This observational learning probably involved the acquisition of an efficient strategy through spatial exploration.

Receiving of emotional signal of pain from conspecifics in laboratory rats.

Though recent studies have shown that rodents express emotions with their face, whether emotional expression in rodents has a communicative function between conspecifics is still unclear. Here, we demonstrate the ability of visual recognition of emotional expressions in laboratory rats. We found that Long-Evans rats avoid images of pain expressions of conspecifics but not those of neutral expressions. The results indicate that rats use visual emotional signals from conspecifics to adjust their behaviour in an environment to avoid a potentially dangerous place. Therefore, emotional expression in rodents, rather than just a mere 'expression' of emotional states, might have a communicative function.

The combination of perception of other individuals and exogenous manipulation of arousal enhances social facilitation as an aftereffect: re-examination of Zajonc's drive theory.

Zajonc's drive theory postulates that arousal enhanced through the perception of the presence of other individuals plays a crucial role in social facilitation (Zajonc, 1965). Here, we conducted two experiments to examine whether the elevation of arousal through a stepping exercise performed in front of others as an exogenous factor causes social facilitation of a cognitive task in a condition where the presence of others does not elevate the arousal level. In the main experiment, as an "aftereffect of social stimulus," we manipulated the presence or absence of others and arousal enhancement before participants conducted the primary cognitive task. The results showed that the strongest social facilitation was induced by the combination of the perception of others and arousal enhancement. In a supplementary experiment, we manipulated these factors by adding the presence of another person during the task. The results showed that the effect of the presence of the other during the primary task is enough on its own to produce facilitation of task performance regardless of the arousal enhancement as an aftereffect of social stimulus. Our study therefore extends the framework of Zajonc's drive theory in that the combination of the perception of others and enhanced arousal as an "aftereffect" was found to induce social facilitation especially when participants did not experience the presence of others while conducting the primary task.

An experimental task to examine the mirror system in rats.

The mirror system in the brain is considered to be a neural basis of sociality, but previous studies have been limited to primates. Here we report an experimental task to examine the mirror system in rats. We show that a rat could reach to a pellet and grasp and eat it in front of another rat that was observing the reaching, which indicates that the task will enable us to start exploring the rat mirror system.