Sensory Receptors and Sensations

Introduction: In your body and all throughout, especially in the skin are different types of sensory receptors that have specific jobs. They tell you if you are feeling pain, pressure, temperatures, as well as where you body is in relation to space.

Types:

1. Chemoreceptors: respond to chemical substances in immediate vicinity

2. Pain Receptors: a type of chemoreceptor that responds to chemicals released

by damaged tissues

3. Photoreceptors: respond to light energy (in our eyes)

4. Mechanoreceptors: stimulated by mechanical forces

5. Thermoreceptors: stimulated by changes in temperature

The How

*The How of Sensation

1. One of the afore mentioned sensory receptor responds to the change

2. The receptor cells trigger the action potential in connecting sensory neurons

3. Spinal cord and/or Brain process the where, what, how much/strong?

Sensory Fields

*Sensory Fields

*Large fields in the brain organize information spatially

1. Visual Cortex: forms the visual field/complete visual image

2. Sensory Cortex: Touch sensation from entire skin surface

Frolich used a great photo of the sensory fields from Sylvia S. Mader's book "Human Biology" on page 258. I attempted to find it to paste here with no luck.

Conclusion: Again, a simple view of how we sense things. The next section is going to introduce us to proprioceptors, cutaneous, and pain receptors.