Which statement most accurately describes the mechanism that allows us to sense warmth and coolness?
◦ There are only receptors for warmth and they work like a thermometer.
◦ There are only receptors for coolness and they work like a thermometer.
◦ The brain integrates separate warm and cool signals.
◦ Meissner corpuscles sense warmth and Merkel disks sense coolness; inputs from these receivers are directly "felt" by the brain.