Effects of constant daylight exposure during early development on marmoset psychosocial behavior

A Susceptible Period of Photic Day-Night Rhythm Loss in Common Marmoset Social Behavior Development

The prevalence of neurodevelopmental psychiatric disorders such as pervasive developmental disorders is rapidly increasing worldwide. Although these developmental disorders are known to be influenced by an individual’s genetic background, the potential biological responses to early life’s environmental exposure to both physical and psychological factors must also be considered. Many studies have acknowledged the influence of shorter time for rest at night and the simultaneous occurrence of various kinds of complications involving developmental disorders. In a prior study, we examined how a common marmoset’s (Callithrix jacchus) psychosocial development was affected when it was reared under constant daylight from birth and then reared individually by humans nursing them under constant light (LL) during their juvenile development stages. The behaviors of these marmosets were compared with those of normal day-night cycle (LD) marmosets using a multivariate analysis based on principal component analysis (PCA). That study found that LL marmosets relatively elicited egg-like calls (Ecall) and side-to-side shakes of the upper body with rapid head rotation through adulthood frequently. Based on the PCA, these behaviors were interpreted as “alert” or “hyperactive” states. However, we did not clarify susceptible periods of the photic rhythm loss experience and the psychological development output. In this study we summarize the following studies in our model animal colonies involving 30 animals (11 female, 19 males) to further explore critical age states of inquiry about each social behavior profiling. We compared social behaviors of three age stages, juvenile, adolescent and young adult equivalent to one another in four LL experience conditions, LL (postnatal day (P) 0 to around 150), Middle (P60–149, 90 days), Late (P150–239, 90 days), and LD (no experience). In the most representative 1st and 2nd principal component scores, the shifting to higher frequency of alert behaviors developed at the adult stage in LL, Middle, then Late in turn. The no LL experience group, LD, generally featured higher frequency of local preference of high position compared to LL experience present groups, in adulthood. This limited model primate study might inspire different developmental age sensitive mechanisms of neuronal network to control socio-emotional functions by utilizing the multivariate visualization method, BOUQUET. This study could potentially contribute to nurturing educational designs for social developmental disorders.

Inexpensive Home Infrared Living/Environment Sensor with Regional Thermal Information for Infant Physical and Psychological Development

The use of home-based image sensors for biological and environmental monitoring provides novel insight into health and development but it is difficult to evaluate people during their normal activities in their home. Therefore, we developed a low-cost infrared (IR) technology-based motion, location, temperature and thermal environment detection system that can be used non-invasively for long-term studies in the home environment. We tested this technology along with the associated analysis algorithm to visualize the effects of parental care and thermal environment on developmental state change in a non-human primate model, the common marmoset (Callithrix jacchus). To validate this system, we first compared it to a manual analysis technique and we then assessed the development of circadian rhythms in common marmosets from postnatal day 15–45. The semi-automatically tracked biological indices of locomotion velocity (BV) and body surface temperature (BT) and the potential psychological index of place preference toward the door (BD), showed age-dependent shifts in circadian phase patterns. Although environmental variables appeared to affect circadian rhythm development, principal component analysis and signal superimposing imaging methods revealed a novel phasic pattern of BD-BT correlation day/night switching in animals older than postnatal day 38 (approximately equivalent to one year of age in humans). The origin of this switch was related to earlier development of body temperature (BT) rhythms and alteration of psychological behavior rhythms (BD) around earlier feeding times. We propose that this cost-effective, inclusive sensing and analytic technique has value for understanding developmental care conditions for which continual home non-invasive monitoring would be beneficial and further suggest the potential to adapt this technique for use in humans.

Elderly Body Movement Alteration at 2nd Experience of Digital Art Installation with Cognitive and Motivation Scores

The prevalence of advanced medical treatment has led to global population aging, resulting in increased numbers of dementia patients. One of the most intractable symptoms of dementia is apathy, or lack of interest and enthusiasm, which can accompany memory and cognitive deterioration. Development of a novel method to ameliorate apathy is desirable. In this feasibility trial, we propose a series of digital art installations as a candidate dementia intervention approach. Seven, three-minute scenes of digital images and sounds were presented to visitors either passively or in response to their reactions (motion and sound). We evaluated the potential of this application as an intervention against apathy in an elderly living home. We collected the dementia global standard Mini-Mental State Examination (MMSE) and questionnaire scores of sensory pleasure and motivation along with behavioral motion data in twenty participants. We further compared responses between the first and second experiences in the thirteen participants that were present for both days. Overall, we found a significant increase in participants’ motivation. In these subjects, head and right hand motion increased over different scenes and MMSE degrees, but was most significant during passive scenes. Despite a small number of subjects and limited evaluations, this new digital art technology holds promise as an apathy intervention in the elderly and can be improved with use of wearable motion sensors.

Early-infant diagnostic predictors of the neuro-behavioral development after neonatal care

Multidimensional diagnosis plays a central role in infant developmental care, which leads to the prediction of future disabilities. Information consolidated from objective and subjective, early and late, central and peripheral data may reveal neuro-pathological mechanisms and realize earlier and more precise preventive intervention. In the current study, we retrospectively searched correlating factors to the following neurological and behavioral development of 'Head Control' and 'Roll Over' using multivariate correlation analysis of differ-ent diagnostic domains over age, subject/object information of the patients who were previously admitted in our neonatal intensive care unit (NICU) and could be developmentally followed up in our outpatient clinic. Based on the hematologic and biochemical data, MRI brain anatomy during NICU hospitalization, we characterized all the acquired data distribution from 31 infants with either 'appeared neurologically normal (ANN, n = 21)’ or 'appeared neurologically abnormal (ANA, n = 10)’ pro tempore, with a physician's clinical judgment before discharge. Besides single factor comparisons between ANN and ANA, we examined their development difference by using the multidimensional information processing, principal component analysis (PCA). The diagnostic predictors of neuro-behavioral development were selected by regression analysis with variable selection. It resulted that hematological and brain anatomical factors seemed correlated to both ‘Head Control’ and ‘Roll Over’. This report suggested certain possibility of the cross-domain translational approach between subjective and objective developmental information through multivariate analyses, with candidate markers preliminarily to be evaluated in further studies.

Susceptible period of socio-emotional development affected by constant exposure to daylight

As a diurnal experimental primate, the common marmoset (Callithrix jacchus) has recently contributed to numerous kinds of studies of neurobiological psychiatry as an essential pre-clinical model. The marmoset matures sexually within one or two years after birth. Thus, we can observe how the primate learns and develops psycho-cognitive functions through experiences in experimental environment for a much shorter period compared to that of humans. Longer daylight exposure may affect psychological development of children. In our research, we focus on raising marmosets under constant daylight from birth until various ages. In order to quantitatively evaluate the development of higher-ordered psychological functions, we designed a system of socio-behavioral tests and multivariate correlation analysis methods based on principal component analysis. With reference to the call and typical body movement expressed during a particular social context, we statistically inferred the emotional features of the subjects. In the current literature, we review our published results showing increased alert behaviors by constant light, and then, attempted to extend our additional analysis to seek age-dependent susceptibility to constant light. We then present the neurobiological mechanisms with reference to previous research reports. The current review suggests possible existence of a susceptible period earlier than three to five month-old in the environment-induced developmental disorder model, supposedly like attention deficit hyperactive disorders (ADHD) or oppositional defiant disorder (ODD).

A cross-species socio-emotional behaviour development revealed by a multivariate analysis

Recent progress in affective neuroscience and social neurobiology has been propelled by neuro-imaging technology and epigenetic approach in neurobiology of animal behaviour. However, quantitative measurements of socio-emotional development remains lacking, though sensory-motor development has been extensively studied in terms of digitised imaging analysis. Here, we developed a method for socio-emotional behaviour measurement that is based on the video recordings under well-defined social context using animal models with variously social sensory interaction during development. The behaviour features digitized from the video recordings were visualised in a multivariate statistic space using principal component analysis. The clustering of the behaviour parameters suggested the existence of species- and stage-specific as well as cross-species behaviour modules. These modules were used to characterise the behaviour of children with or without autism spectrum disorders (ASDs). We found that socio-emotional behaviour is highly dependent on social context and the cross-species behaviour modules may predict neurobiological basis of ASDs.

Potential of a smartphone as a stress-free sensor of daily human behaviour

Behaviour is one of the most powerful objective signals that connotes psychological functions regulated by neuronal network systems. This study searched for simple behaviours using smartphone sensors with three axes for measuring acceleration, angular speed and direction. We used quantitative analytic methodology of pattern recognition for work contexts, individual workers and seasonal effects in our own longitudinally recorded data. Our 13 laboratory members were involved in the care of common marmosets and domestic chicks, which lived in separate rooms. They attached a smartphone to their front waist-belts during feeding and cleaning in five care tasks. Behavioural characteristics such as speed, acceleration and azimuth, pitch, and roll angles were monitored. Afterwards, participants noted subjective scores of warmth sensation and work efficiency. The multivariate time series behavioral data were characterized by the subjective scores and environmental factors such as room temperature, season, and humidity, using the linear mixed model. In contrast to high-precision but stress-inducing sensors, the mobile sensors measuring daily behaviours allowed us to quantify the effects of the psychological states and environmental factors on the behavioural traits.

A flexion period for attachment formation in isolated chicks to unfamiliar peers visualized in a developmental trajectory space through behavioral multivariate correlation analysis

Attachment formation is crucial for social animals to survive in natural environments. Predisposition and imprinting mechanisms have been well documented as a process of con-specific affiliation development. However, it is unclear how neonatal stage attachment formation leads to juvenile peer sociality. Here we have developed an animal model (Gallus gallus domesticus) and a method of quantitative behavioral analysis, to study the developmental trajectory from postnatal day (P) 3 through to P21. Domestic chicks were raised in either group or isolated conditions and we focused on social behavior during a two-minute meeting context with unfamiliar group peers at P3, 7, 13, 16, and 21. Results showed that relative to isolated chicks, group reared chicks were more active behaviorally, when facing peers at P3 and that this activity declined slightly over development, up to P13. Isolated chicks that had not met any animals except humans, exhibited a major change in social behavior around P7, in particular, with increasing activity (head moving velocity and rotation velocity) and distress calls. This modulation disappeared after P13, suggesting the existence of a sensitive window for behavior toward peers around P7. These findings in isolated chicks suggest the maturation of new neuronal substrates for peer-social emotion and cognition, resulting in a new combination of behavioral modules.

Peer attachment formation by systemic redox regulation with social training after a sensitive period

Attachment formation is the most pivotal factor for humans and animals in the growth and development of social relationships. However, the developmental processes of attachment formation mediated by sensory-motor, emotional, and cognitive integration remain obscure. Here we developed an animal model to understand the types of social interactions that lead to peer-social attachment formation. We found that the social interaction in a sensitive period was essential to stabilise or overwrite the initially imprinted peer affiliation state and that synchronised behaviour with others based on common motivations could be a driver of peer social attachment formation. Furthermore, feeding experience with supplementation of ubiquinol conferred peer social attachment formation even after the sensitive period. Surprisingly, the experience of feeding beyond the cage window was also effective to reduce the required amount ubiquinol, suggesting that peri-personal space modulation may affect socio-emotional cognition and there by lead to attachment formation.