Biological rhythms as organization and information

A non-parametric model: free analysis of actigraphic recordings of acute insomnia patients

Both parametric and non-parametric approaches to time-series analysis have advantages and drawbacks. Parametric methods, although powerful and widely used, can yield inconsistent results due to the oversimplification of the observed phenomena. They require the setting of arbitrary constants for their creation and refinement, and, although these constants relate to assumptions about the observed systems, it can lead to erroneous results when treating a very complex problem with a sizable list of unknowns. Their non-parametric counterparts, instead, are more widely applicable but present a higher detrimental sensitivity to noise and low density in the data. For the case of approximately periodic phenomena, such as human actigraphic time series, parametric methods are widely used and concepts such as acrophase are key in chronobiology, especially when studying healthy and diseased human populations. In this work, we present a non-parametric method of analysis of actigraphic time series from insomniac patients and healthy age-matched controls. The method is fully data-driven, reproduces previous results in the context of activity offset delay and, crucially, extends the concept of acrophase not only to circadian but also for ultradian spectral components.

Melatonin Relations With Respiratory Quotient Weaken on Acute Exposure to High Altitude

High altitude (HA) exposure may affect human health and performance by involving the body timing system. Daily variations of melatonin may disrupt by HA exposure, thereby possibly affecting its relations with a metabolic parameter like the respiratory quotient (RQ). Sea level (SL) volunteers (7 women and 7 men, 21.0 ± 2.04 y) were examined for daily changes in salivary melatonin concentration (SMC). Sampling was successively done at SL (Antofagasta, Chile) and, on acute HA exposure, at nearby Caspana (3,270 m asl). Saliva was collected in special vials (Salimetrics Oral Swab, United Kingdom) at sunny noon (SMC_D) and in the absence of blue light at midnight (SMC_N). The samples were obtained after rinsing the mouth with tap water and were analyzed for SMC by immunoassay (ELISA kit; IBL International, Germany). RQ measurements (n = 12) were realized with a portable breath to breath metabolic system (Oxicon^TM Mobile, Germany), between 8:00 PM and 10:00 PM, once at either location. At SL, SMC_D, and SMC_N values (mean ± SD) were, respectively, 2.14 ± 1.30 and 11.6 ± 13.9 pg/ml (p < 0.05). Corresponding values at HA were 8.83 ± 12.6 and 13.7 ± 16.7 pg/ml (n.s.). RQ was 0.78 ± 0.07 and 0.89 ± 0.08, respectively, at SL and HA (p < 0.05). Differences between SMC_N and SMC_D (SMC_N-SMC_D) strongly correlate with the corresponding RQ values at SL (r = -0.74) and less tight at HA (r = -0.37). Similarly, mean daily SMC values (SMC) tightly correlate with RQ at SL (r = -0.79) and weaker at HA (r = -0.31). SMC_N-SMC_D, as well as, SMC values at SL, on the other hand, respectively, correlate with the corresponding values at HA (r = 0.71 and r = 0.85). Acute exposure to HA appears to loosen relations of SMC with RQ. A personal profile in daily SMC variation, on the other hand, tends to be conserved at HA.

The scale-free dynamics of eukaryotic cells

Temporal organization of biological processes requires massively parallel processing on a synchronized time-base. We analyzed time-series data obtained from the bioenergetic oscillatory outputs of Saccharomyces cerevisiae and isolated cardiomyocytes utilizing Relative Dispersional (RDA) and Power Spectral (PSA) analyses. These analyses revealed broad frequency distributions and evidence for long-term memory in the observed dynamics. Moreover RDA and PSA showed that the bioenergetic dynamics in both systems show fractal scaling over at least 3 orders of magnitude, and that this scaling obeys an inverse power law. Therefore we conclude that in S. cerevisiae and cardiomyocytes the dynamics are scale-free in vivo. Applying RDA and PSA to data generated from an in silico model of mitochondrial function indicated that in yeast and cardiomyocytes the underlying mechanisms regulating the scale-free behavior are similar. We validated this finding in vivo using single cells, and attenuating the activity of the mitochondrial inner membrane anion channel with 4-chlorodiazepam to show that the oscillation of NAD(P)H and reactive oxygen species (ROS) can be abated in these two evolutionarily distant species. Taken together these data strongly support our hypothesis that the generation of ROS, coupled to redox cycling, driven by cytoplasmic and mitochondrial processes, are at the core of the observed rhythmicity and scale-free dynamics. We argue that the operation of scale-free bioenergetic dynamics plays a fundamental role to integrate cellular function, while providing a framework for robust, yet flexible, responses to the environment.

Gene expression, neurogenesis, and healing: psychosocial genomics of therapeutic hypnosis

The historical lineage of therapeutic hypnosis in James Braid's "psychophysiology", Pierre Janet's "physiological modification", and Milton Erickson's "neuro-psycho-physiology" is extended to include current neuroscience research on activity-dependent gene expression, neurogenesis, and stem cells in memory, learning, behavior change, and healing. Three conditions that optimize gene expression and neurogenesis--novelty, environmental enrichment, and exercise--could integrate fundamentals of the theory, research, and practice of therapeutic hypnosis. Continuing research on immediate-early, activity-dependent, behavior state-related, and clock gene expression could enhance our understanding of how relaxation, sleep, dreaming, consciousness, arousal, stress and trauma are modulated by therapeutic hypnosis. It is speculated that therapeutic and post-hypnotic suggestion could be focused more precisely with the time parameters of gene expression and neurogenesis that range from minutes and hours for synthesizing new synapses to weeks and months for the generation and maturation of new, functioning neurons in the adult brain.

In search of a deep psychobiology of hypnosis: visionary hypotheses for a new millennium

This search for the deep psychobiological foundations of hypnosis begins with a review of some of the paradoxes of historical hypnosis and the impasse of current theory. It is proposed that further progress requires a deeper investigation of how psychosocial cues can modulate the mechanisms of healing at the CNS, autonomic, neuroendocrine and cellular-genetic levels. The dynamics of hypnotic communication and healing from the cognitive-behavior level to the cellular-genetic are outlined in four stages: (1) Information transduction between the experiences of consciousness and the limbic-hypothalamic-pituitary system; (2) The psychosomatic network of messenger molecules and their receptors; (3) The immediate early gene protein cascade; and (4) State dependent memory, learning and behavior. Neuroscience research is outlined for its contributions to a mathematical model of how a psychobiological approach to the therapeutic applications of hypnosis and the placebo response could facilitate neurogenesis in the human hippocampus and healing at the cellular-genetic-protein level throughout the body. A series of ten hypotheses is proposed as a guide for theory and research in therapeutic hypnosis utilizing DNA chip technology in the new millennium.

The Feigenbaum scenario as a model of the limits of conscious information processing

The Feigenbaum scenario of the mathematical period doubling sequence from order to deterministic chaos has led to new insights about the nonlinear dynamics of a wide variety of physical and biological systems. Multiple realms from purely mechanical systems, fluid dynamics and weather to the patterns of biological growth and the dynamic of the heart, hormone and brain rhythms have been found to exhibit aspects of the Feigenbaum period doubling sequence. We explore the possibility that the Feigenbaum scenario can be extended to experiences of sensation, perception and human cognition as well. We also review the empirical data that supports the view that the Feigenbaum scenario of the period doubling sequence may portray an important limit in conscious information processing. We conclude that a major function of consciousness may be to transform the nonlinear, irrational and difficult to predict dynamics of unconscious nature into the more linear, rational and predictable psychodynamics that make human experience and social life possible.

Circadian and ultradian clock-controlled rhythms in unicellular microorganisms

The time structure of a biological system is at least as intricate as its spatial structure. Whereas we have detailed information about the latter, our understanding of the former is still rudimentary. As techniques for monitoring intracellular processes continuously in single cells become more refined, it becomes increasingly evident that periodic behaviour abounds in all time domains. Circadian timekeeping dominates in natural environments. Here the free-running period is about 24 h. Circadian rhythms in eukaryotes and prokaryotes allow predictive matching of intracellular states with environmental changes during the daily cycles. Unicellular organisms provide excellent systems for the study of these phenomena, which pervade all higher life forms. Intracellular timekeeping is essential. The presence of a temperature-compensated oscillator provides such a timer. The coupled outputs (epigenetic oscillations) of this ultradian clock constitute a special class of ultradian rhythm. These are undamped and endogenously driven by a device which shows biochemical properties characteristic of transcriptional and translational elements. Energy-yielding processes, protein turnover, motility and the timing of the cell-division cycle processes are all controlled by the ultradian clock. Different periods characterize different species, and this indicates a genetic determinant. Periods range from 30 min to 4 h. Mechanisms of clock control are being elucidated; it is becoming evident that many different control circuits can provide these functions.

The psychobiology of mind-body communication: the complex, self-organizing field of information transduction

The current information revolution in molecular biology has important implications for an new understanding of the phenomenology of mind, memory and behavior as a complex, self-organizing field of information transduction. This paper traces the pathways of information transduction in life processes from the molecular-genetic level to the dynamics of mind and behavior together with suggestions for future research exploring the psychobiology of mind-body communication and its implications for the psychotherapeutic arts of the future.

Ageing, oscillations and efficiency

The phenomenon of ageing still defies understanding. Theoretical studies have indicated that glycolysis is more efficient at maintaining a high ATP/ADP ratio when oscillating at its resonant frequency. Earlier, it was proposed that the differentiated state results from the establishment of a stable pattern of temporal organisation. It is now suggested that ageing involves a decrease in efficiency due to the detuning of oscillating glycolysis as a result of frequency locking with other cellular oscillations in the differentiated state.