Physiology's ImpactLiving Together in SocietyDavid MegirianDavid MegirianTasmania, AustraliaPublished Online:01 May 2015https://doi.org/10.1152/physiol.00060.2014MoreSectionsPDF (39 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Most mammals are acknowledged as social beings. Rats are as much social creatures as are humans: rats too live in aggregates. It is reasonable to assume that its members communicate with each other in distinctive and diverse ways. Here, the emphasis is not on “linguistic” modes of communication but along broader and fundamental considerations. This is not the communication in which one nerve cell synapses with another one within the central nervous system. Rather, communication is by recognizing coherence of sights or images, sounds, and odors processed by the mammalian brain's neural networks and systems (6, 10).Bowlby couched the idea of patterns for us as “an understanding of function [that] requires a study of a population of individuals and is impossible if the unit of study is the individual alone” (6). Bateson succinctly stated how important patterns are: “It is impossible, in principle, to explain any patterns by invoking a single quantity” (1). We need to have a propensity “to see the forest (neural networks) and less the trees (synapses)” (1).Synaptic transmission in the central nervous system is widely accepted to be mediated by chemical transmitters: acetylcholine, the monoamines, endorphins, and other hormonal secretions. Louis Cozolino viewed these transmitters at synapses as the chemicals released into the gaps between nerve cells. By analogy, he envisioned the social synapse as the gap between one individual and the next as transmitters of “smiles, waves, a hello, odors and sounds–and words” (6). They are representational patterns of our neurophysiology and behavior (10).In a cohort of rats, a realistic and working model of the experimental laboratory, the social synaptic modes of communication are licking and grooming, ultrasonic calls, alarm, and other pheromone secretions. Other determining and influencing factors include the presence or absence of light, sleep/wake cycles, and circadian, ultradian, infradian, and free-running rhythms. It is the regulatory cues and markers by which a cohort of rats achieves relational homeostasis, demonstrated by the maintenance of metabolism and thermal, water, and electrolyte balances and many other bodily functions.Using the rat as an example, the newborn pup has initially no sight or pelage; alone it cannot stand and has very limited mobility. It is unable independently to obtain nourishment from the environment. The mother rat nourishes her offspring from her breast milk and ensures their huddling or nesting. Her licking and grooming promote excretion of her pups' waste products. The human newborn experiences a similar early period of developmental care-giving of the mother, which is not basically different from those of a mothering rat.The extant literature is replete with examples of aggregate homeostasis in cohorts of the rat. Kask et al. (7) removed rats in a triad one after another from a single chamber, and then measured the body temperature of those remaining in that chamber. They found that those rats remaining, after successive removals, had significantly elevated body temperatures. Studies of a similar type have revealed an elevation of body temperature, which is autonomically mediated, without affecting the animal's navigation of a plus-maze, a somatic motivated behavior (9).Bishop and coworkers (2–4) employed a cohort paradigm. In this design, a given rat of a group of animals is chronically implanted with a probe to detect biotelemetrically its body temperature and spontaneous locomotor activity. Each rat is housed in a wire mesh cage. In turn, 4–6 such caged rats, i.e., a cohort, are lodged in a large plastic chamber. Bishop and coworkers employed this experimental paradigm to examine changes in body temperature, locomotor activity, and respective circadian rhythms as a function of the thermal, photic, and oxygen environments. Their findings revealed that the regulation of body temperature, activity, and circadian rhythms differs from that of the individual rat (8).Although we have acquired much knowledge from empirical studies of an individual's physiology and pathology as in the rat or in the human, our knowledge of “us” in relationships and with the environment is sorely lacking. The trumpet sounded here is an echo of Bowlby, Bateson, and many others since; the call to pursue empirical studies of the healthy, the ill, or the disabled in societies. How many times has the practicing physician taken my blood pressure to find it elevated: hypertensive? On continuing the review, conducted in a calm and soothing manner, a later measurement reveals my blood pressure then in the normal range. In the case of the next patient, perhaps his or her blood pressure remains elevated at that subsequent measurement. Mine is the “White coat effect” of a stressful interview; hypertension diagnosed for the next patient may be stress of another kind, due to experience in the family or the community.FOOTNOTESNo conflicts of interest, financial or otherwise, are declared by the author(s).
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Apr 6, 2019
L Michelle Gilley + 3
Open Access