Why does targeted disruption of the preoptic area of the hypothalamus cause poikilothermia in mammals, rather than simply resetting the body's temperature set point?

💡 Explanation

The hypothalamus integrates sensory input to activate a range of thermoregulatory responses like shivering and sweating; therefore, disrupting the preoptic area disables the entire coordinated response, rather than just changing the set point, because it is the central integrator.

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