• Get into a group of 3 with the people who have the same Case # as you on their Do Now paper.
• Read the article and summarize it as a group.
Choose someone to speak for your group!

• Identify and explain the different types of sensory receptors.
• Explain referred and phantom pain.
• Compare and contrast acute and chronic pain.

1 0 . 1 - 1 0 . 4

• The sensation of pain in a limb that has been amputated.
• Causes aren’t completely understood
• damaged nerve endings, scar tissue at the site of the amputation and the physical memory of pre-amputation pain in the affected area http://www.youtube.com/watch?v=YL
_6OMPywnQ

• What is phantom pain?
• What causes it?
• What is mirror therapy?
• How else could someone alleviate this pain?

• Identify and explain the different types of sensory receptors.
• Explain referred and phantom pain.
• Compare and contrast acute and chronic pain.

• http://www.youtube.com/watch?v=hlQZmNlPdHQ

Sensation
• formed based on the sensory input from receptors
• how brain interprets it
• Projection
• Brain sends the sensation back to its point of origin
• person can pinpoint the area of stimulation

• Remember the 2 point discrimination in the lab?
• Which part of your body had a larger receptive field?

• Before reading this sentence, could you feel your clothes on your skin?
• The ability to ignore unimportant stimuli is called sensory adaptation.

• Somatic senses
• touch, pressure,
smell, taste, hearing, equilibrium, vision

• Chemoreceptors
• Thermoreceptors
• Photoreceptors
• Mechanoreceptors
• Pain receptors (Nociceptors)

• respond to changes in chemical concentrations
• Ex: Monitor CO
2 levels in blood and pH

• Respond to changes in temperature

• Place your pointer finger on your right hand in cold water and the same finger on your left hand in warm water.
• Leave them in there for 1 minute
• Now place them both in the room temperature water.
• 

• Responds to light
• Rods- respond to light
• Cones- respond to colors

• Hold the ends of a pencil, one in each hand. Hold them horizontally facing each other at arms-length from your body.
• 2. With one eye closed, try to touch the end of the pencils together.
• 3. Now try with two eyes.
• What did you experience?

Free nerve endings
• common in epithelial tissues
• simplest receptors
• sense itching
Meissner’s corpuscles
• abundant in hairless portions of skin; lips
• detect fine touch; distinguish between two points on the skin
Pacinian corpuscles
• common in deeper subcutaneous tissues, tendons, and ligaments
• detect heavy pressure and vibrations

• “Nociceptors”-
• found on free nerve endings
• Respond to tissue damage
Pain receptor clip: http://www.nlm.nih.gov/medlineplus/e ncy/anatomyvideos/000054.htm

• Acute pain fibers:
• Relatively thin, myelinated
• Rapid impulse conduction, causing sharp pain
• Chronic pain fibers:
• Thin, unmyelinated
• Conduct impulses slowly, produce a dull aching sensation

• may occur due to sensory impulses from two regions following a common nerve pathway to brain
• Ex:
• Someone experiencing a heart attack may feel pain in their left shoulder

• What receptors detect deep pressure?
• What is the difference between acute and chronic pain?
• Where do you have the most receptive fields?
**Monday- bring your books and notes to class! We are going to start reviewing for midterms.