Quantification of Irregular Rhythms in Chronobiology: A Time- Series Perspective

In optimal conditions of youth and health, most—if not all—physiological systems obey regular circadian rhythms in response to the periodic day-night cycle and can be well described by standard techniques such as cosinor analysis. Adverse conditions can disturb the regularity and amplitude of circadian cycles, and, recently, there is interest in the field of chronobiology to quantify irregularities in the circadian rhythm as a means to track underlying pathologies. Alterations in physiological rhythms over a wide range of frequency scales may give additional information on health conditions but are often not considered in traditional analyses. Wavelets have been introduced to decompose physiological time series in components of different frequencies and can quantify irregular patterns, but the results may depend on the choice of the mother wavelet basis which is arbitrary. An alternative approach are recent data-adaptive time-series decomposition techniques, such as singular spectrum analysis (SSA), where the basis functions are generated by the data itself and are user-independent. In the present contribution, we compare wavelets and SSA analysis for the quantification of irregular rhythms at different frequency scales and discuss their respective advantages and disadvantages for application in chronobiology

The Feeling Is Mutual: Clarity of Haptics-Mediated Social Perception Is Not Associated With the Recognition of the Other, Only With Recognition of Each Other

The enactive theory of perception hypothesizes that perceptual access to objects depends on the mastery of sensorimotor contingencies, that is, on the know-how of the regular ways in which changes in sensations depend on changes in movements. This hypothesis can be extended into the social domain: perception of other minds is constituted by mastery of self-other contingencies, that is, by the know-how of the regular ways in which changes in others’ movements depend on changes in one’s movements. We investigated this proposal using the perceptual crossing paradigm, in which pairs of players are required to locate each other in an invisible one-dimensional virtual space by using a minimal haptic interface.We recorded and analyzed the real-time embodied social interaction of 10 pairs of adult participants. The results reveal a process of implicit perceptual learning: on average, clarity of perceiving the other’s presence increased over trials and then stabilized. However, a clearer perception of the other was not associated with correctness of recognition as such, but with both players correctly recognizing each other. Furthermore, the moments of correct mutual recognition tended to happen within seconds. The fact that changes in social experience can only be explained by the successful performance at the level of the dyad, and that this veridical mutual perception tends toward synchronization, lead us to hypothesize that integration of neural activity across both players played a role

Multi-Scale Coordination of Distinctive Movement Patterns During Embodied Interaction Between Adults With High-Functioning Autism and Neurotypicals

Autism Spectrum Disorder (ASD) can be understood as a social interaction disorder. This requires researchers to take a “second-person” stance and to use experimental setups based on bidirectional interactions. The present work offers a quantitative description of movement patterns exhibited during computer-mediated real-time sensorimotor interaction in 10 dyads of adult participants, each consisting of one control individual (CTRL) and one individual with high-functioning autism (HFA). We applied time-series analyses to their movements and found two main results. First, multi-scale coordination between participants was present. Second, despite this dyadic alignment and our previous finding that individuals with HFA can be equally sensitive to the other’s presence, individuals’ movements differed in style: in contrast to CTRLs, HFA participants appeared less inclined to sustain mutual interaction and instead explored the virtual environment more generally. This finding is consistent with social motivation deficit accounts of ASD, as well as with hypersensitivity-motivated avoidance of overstimulation. Our research demonstrates the utility of time series analyses for the second-person stance and complements previous work focused on non-dynamical and performance-based variables

Multi-scale coordination of distinctive movement patterns during embodied interaction between adults with high-functioning autism and neurotypicals

Funding We acknowledge financial support from DGAPA-PAPIIT projects of the Universidad Nacional Autónoma de México: IA105017 (RF and LZ-F) and IA104717 (TF), Consejo Nacional de Ciencia y Tecnología (CONACyT) projects 167441 (RF and LZ-F), the scholarship 638215 to LZ-F granted by the CONACyT, the Newton Advanced Fellowship awarded to RF by the Academy of Medical Sciences, through the UK Government’s Newton, and the Marie Curie Intra-European Fellowship “SOCIAL BRAIN” awarded to BT. Acknowledgments We thank Charles Lenay and Dominique Aubert from the Université de Technologie de Compiègne for making the TACTOS hardware and software available to the University Hospital Cologne, and for providing technical support. LZ-F would like to specially thank Jesús Naveja and Lilia Fonseca for interesting discussions. SUPPLEMENTARY MATERIAL The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fpsyg.2018.02760/full#supplementary-materialPeer reviewedPublisher PD

Multiscale adaptive analysis of circadian rhythms and intradaily variability: Application to actigraphy time series in acute insomnia subjects

Circadian rhythms become less dominant and less regular with chronic-degenerative disease, such that to accurately assess these pathological conditions it is important to quantify not only periodic characteristics but also more irregular aspects of the corresponding time series. Novel data-adaptive techniques, such as singular spectrum analysis (SSA), allow for the decomposition of experimental time series, in a model-free way, into a trend, quasiperiodic components and noise fluctuations. We compared SSA with the traditional techniques of cosinor analysis and intradaily variability using 1-week continuous actigraphy data in young adults with acute insomnia and healthy age-matched controls. The findings suggest a small but significant delay in circadian components in the subjects with acute insomnia, i.e. a larger acrophase, and alterations in the day-to-day variability of acrophase and amplitude. The power of the ultradian components follows a fractal 1/f power law for controls, whereas for those with acute insomnia this power law breaks down because of an increased variability at the 90min time scale, reminiscent of Kleitman&rsquo;s basic rest-activity (BRAC) cycles. This suggests that for healthy sleepers attention and activity can be sustained at whatever time scale required by circumstances, whereas for those with acute insomnia this capacity may be impaired and these individuals need to rest or switch activities in order to stay focused. Traditional methods of circadian rhythm analysis are unable to detect the more subtle effects of day-to-day variability and ultradian rhythm fragmentation at the specific 90min time scale.<br /

Investigating real-time social interaction in pairs of adolescents with the Perceptual Crossing Experiment

The study of real-time social interaction provides ecologically valid insight into social behavior. The objective of the current research is to experimentally assess real-time social contingency detection in an adolescent population, using a shortened version of the Perceptual Crossing Experiment (PCE). Pairs of 148 adolescents aged between 12 and 19 were instructed to find each other in a virtual environment interspersed with other objects by interacting with each other using tactile feedback only. Across six rounds, participants demonstrated increasing accuracy in social contingency detection, which was associated with increasing subjective experience of the mutual interaction. Subjective experience was highest in rounds when both participants were simultaneously accurate in detecting each other\u27s presence. The six-round version yielded comparable social contingency detection outcome measures to a ten-round version of the task. The shortened six-round version of the PCE has therefore enabled us to extend the previous findings on social contingency detection in adults to an adolescent population, enabling implementation in prospective research designs to assess the development of social contingency detection over time

Capacity for social contingency detection continues to develop across adolescence

The capacity for dynamically coordinating behaviour is assumed to have largely matured in infancy. In adolescence—another sensitive period for social development—the primary focus on individual social cognition as the main driver of interaction has prevented the study of actual social interaction as behavioural coordination within dyads. From a dynamic perspective, however, capturing real-time social dynamics is essential for the assessment of social interactive processes. In order to improve the understanding of social development during adolescence, we investigated the potential developmental course of social contingency detection in dynamic interactions. Pairs of 205 Belgian adolescents (83 male, 122 female), aged 11–19, engaged in real-time social interaction via the Perceptual Crossing Experiment (PCE). Comparing early, middle and late adolescents, we found a generally higher performance of late adolescents on behavioural and cognitive measures of social contingency detection, while the reported awareness of the implicitly established social interaction was lower in this group overall. Additionally, late adolescents demonstrated faster improvement of behavioural social coordination throughout the experiment, compared with the other groups. Our results indicate that social interactive processes continue to develop throughout adolescence, which manifests as faster social coordination at the behavioural level. This finding underscores dynamic social interaction within dyads as a new opportunity for identifying altered social development during adolescence