Thermoregulation is the homeostatic process by which biological organisms maintain their temperature within a specific range. Homeostatic regulation is a dynamic process in which physiological mechanisms interact with environmental and behavioral changes to allow the body to adapt to thermal changes. But thermoregulation plays a larger role than just maintaining the body’s temperature setpoint. Thermoregulation has other holistic effects on the bodymind including its physical health, emotional well-being, and social behavior.
Hypothalamus: The Body’s Thermostat
The temperature inside of the body is its core temperature while the temperature on the surface is its shell temperature. When body heat production versus body heat loss is equal then core temperature is about 98.6°F with the shell temperature being between one to six degrees cooler. The control center for heat regulation is in the anterior part of the hypothalamus called the preoptic area.
The skin holds sensory receptors for cold and warmth especially in the fingers, face, and genitals at the surface of the body as well as deep within the body and its viscera. These sensors send impulses regarding heat the cold via C-fibers which travel up the spinothalamic tract to reach the hypothalamus, thalamus, and higher brain regions (Vabba et al., 2015).
As blood temperature increases, preoptic neurons fire at a faster rate and slower when the blood temperature falls. If the core temperature rises above or falls below the metabolic setpoint, then thermoreceptors activate the preoptic area. The hypothalamus responds by sending out neural signals and thyrotropin-releasing hormone to activate the adrenals and thyroid glands to boost metabolic activity via vasodilation, shivering, and cellular activity. If heat loss is detected, the hypothalamus causes vasoconstriction of the blood vessels while activating the sweat glands (Tortora & Derrickson, 2020; Young, 2012).
While the hypothalamus is the center for thermoregulation more recent research indicates it does so within a larger network of independent thermal feedback loops (Vabba et al., 2015).
Thermal Interoception
Interoception is the sensory perception of signals from the body’s surface and the body’s interior. Awareness of interoceptive information can come from changes in environmental temperature, shifts in internal temperature, circadian rhythm changes, and certain tissue pathologies caused by infection, inflammation, autoimmune disease, stress, emotional responses, and social interactions (Vabba et al., 2015).
Body Changes
Changes in body temperature—up or down—affect sleepiness and the ability to maintain sleep. Radical temperature changes can indicate infection, vascular problems, and, in certain cases, cancer (Vabba et al., 2015).
Emotional Regulation
Optimal thermal body experience is associated with alertness, positive mood, and less stress. Disrupted thermoregulation is related to a variety of psychological disorders including anorexia nervosa, mood disorder, and schizophrenia (Vabba et al., 2015).
Social Well-Being
Thermoregulation affects behavior by triggering discomfort which forces a person to take steps to reduce the discomfort such as by changing the body’s location, adjusting clothing, or changing the ambient temperature via heating and air conditioning and avoiding social situations that may cause temperature discomfort. This may include avoiding bodily closeness with other people and so may lead to social isolation and loneliness. Interestingly, feelings of loneliness often lead to warmth-seeking actions (Vabba et al., 2015).
Closing Thoughts
Thermal sensations—the awareness of variation in body temperature—influences not just your physiology and comfort level, but how you feel in terms of emotional and social distance or affiliation. Thermal dysfunction can indicate a serious body malfunction or be related to a serious psychological disturbance. It’s interesting how something as simple a state of plus or minus 98.6° can affect so many experiences and behaviors.
Paul Shane, Ph.D., LMT
Director, Academic Content
References
Tortora, G. & Derrickson, B. (2020). Principles of Anatomy and Physiology, 16th Edition. New York, NY: John Wiley & Sons.
Vabba, A., Scattolin, M., Porciello, G., Panasiti, M., & Aglioti, S. (2015). From feeling chilly to burning up: How thermal signals shape the physiological state of the body and impact physical, emotional, and social well-being. Neuroscience and Biobehavioral Reviews 169, 105992, https://doi.org/10.1016/j.neubiorev.2024.105992.
Young, J. (2012). Hunger, Thirst, Sex, and Sleep: How The Brain Controls Our Passions. Lanham, MA: Rowman & Littlefield Publishers, Inc.