Thermal Receptors and Temperature Perception

The lecture covers thermal sensations, focusing on the pathways related to temperature and pain. It explains the types of thermal receptors, their distribution across the body, and how they respond to different temperature ranges. The structure of the skin and the sensory pathways involved in transmitting these sensations to the CNS are discussed. The lecture also highlights the properties of thermal receptors, including their sensitivity and the concept of the neutral zone, where no temperature sensation is felt.

What are the two main types of thermal receptors discussed in the lecture?

• Cold and warm receptors

• Pain and pressure receptors

• Light and vibration receptors

• Touch and position receptors

Which body area has the highest density of cold spots per square centimeter?

• Fingers

• Lips

• Back

• Trunk

Which system carries sensations of temperature and pain to the CNS?

• Dorsal column-medial lemniscus system

• Spinocerebellar tract

• Anterolateral column

• Corticospinal tract

At what temperature do warm receptors begin to fade out?

• 30 degrees centigrade

• 40 degrees centigrade

• 24 degrees centigrade

• 49 degrees centigrade

How do cold pain fibers respond to extreme cold temperatures?

• They respond like warm receptors

• They are unaffected

• They increase their activity

• They become inactive

What happens to nerve fibers at temperatures between 45 to 50 degrees centigrade?

• They increase their response rate

• They become more sensitive

• They start to get damaged

• They stop responding

Which type of nerve fibers are responsible for carrying cold receptor impulses?

• C fibers

• SI fibers

• Both A-delta and C fibers

• A-delta fibers

What is the neutral zone of temperature where no warm or cold sensation is felt?

• 10 to 20 degrees centigrade

• 40 to 50 degrees centigrade

• 15 to 25 degrees centigrade

• 29 to 36 degrees centigrade

Why is metal felt cooler than wood at the same temperature?

• Metal is a poor conductor of heat

• Wood absorbs more heat

• Metal is a good conductor of heat

• Wood is denser than metal

How does humidity affect the perception of temperature?

• It can make 36 degrees feel uncomfortable

• It makes temperatures feel warmer

• It has no effect

• It makes temperatures feel cooler