Normal body temperature of rats: the setpoint controversy

Area of Science:

• Physiology
• Thermoregulation
• Biophysics

Background:

• The prevailing theory posits that body temperature is regulated by corrective thermoregulatory responses opposing deviations from a setpoint.
• Phenomena like emotional hyperthermia, circadian variations, and exercise-induced temperature rises are often attributed to shifts in this setpoint.
• Fever and anapyrexia present challenges, as thermoregulatory responses appear to align with, rather than oppose, temperature deviations.

Purpose of the Study:

• To critically analyze the scientific validity of setpoint shifts as an explanation for various biothermal phenomena.
• To evaluate whether the setpoint theory, with supplementary hypotheses, remains a testable scientific theory.

Main Methods:

• Critical analysis of existing arguments and hypotheses.
• Examination of the explanatory power of the setpoint shift theory for diverse thermoregulatory events.
• Assessment of the scientific rigor and testability of supplementary ad hoc hypotheses.

Main Results:

• Many arguments attributing biothermal phenomena to setpoint shifts lack critical scientific support.
• Supplementary hypotheses, like setpoint shifts explaining fever, immunize the theory against experimental challenges, undermining its scientific status.
• The current work demonstrates that the setpoint shift hypothesis is insufficient to explain observed thermoregulatory responses.

Conclusions:

• The setpoint theory, particularly when augmented with ad hoc hypotheses, is not a robust scientific explanation for thermoregulation.
• Alternative or refined models are needed to accurately explain complex biothermal phenomena such as fever and circadian variations in body temperature.