Somesthesis

http://www.youtube.com/watch?v

=qoiaUV7fGEI

Top-Down Processing

• Information guided by mental processes– Starts in the brain– Construct perceptions through prior experience

and expectation

Bottom-up Processing

• Begins with sensory information– Works up to brain’s integration of sensory

information

What type of processor are you?

Processing Examples:• I go to the doctor’s office to get shots. I hate getting shots.

This is the worst. I’m going to have the worst time ever. Why do we have to do this today. My parents tricked me – they said we were going to Wendy’s and hotdamn, I love that place… but no this is not Wendy’s, we have to first stop off and get these shots, this is the worst I hate it I hate it I hate it… I get the shot, and I was right, it is the worst thing ever. It hurts. Ow Ow Ow Ow.– Top-down or bottom-up?

• I go to the doctor’s office to get a shot. The doctor sticks me. Ow. It sucks. This is the worst ever.– Top-down or bottom-up?

Touch is an important sense…

• Communication• Love• Attachment• development

But it’s not as easy as having a cone or a rod, or a taste bud…

• There are 4 types of touch, but only pressure has an identifiable receptor site.

1. Pressure2. Warmth3. Cold4. Pain

– Why not hot?

PRESSURE has its own receptors - 0ther skin sensations are just combos of the other four

(pressure, pain, cold, warm)

• Stroking alternating pressure = tickle– You can’t tickle yourself… the brain understands foreign vs. domestic

terrorism• Repeated gentle stroking of pain = itching• Touching cold and pressure = wet

– think of touching really cold and dry metal• Stimulating cold and warm = hot

• But what could hot also be? Top-down or bottom-up?

• http://www.youtube.com/watch?v=sxwn1w7MJvk - Rubber Hand Illusion (which two senses are at play here, and what’s this called?)

Somesthesis• Fancy word for touch

sense• HUMUNCULUS

– Motor and sensory cortex together

• Where are they located in the brain?

• Broken down into two parts– Kinesthesis– Vestibular sense

Kinethesis

• Sense of position and movement of body parts– Enabled by receptors in your joints, tendons,

bones, ears, and skin

• Monitors your head’s (and thus body’s) position and movement– Based off equilibrium in inner ear– Semicircular canals contain vestibular sacs which

connect to the cochlea

Vestibular Sense

Pain

• Your body’s way of saying something has gone wrong.

• Combines bottom-up and top-down– How? Think of examples from beginning of class…

In case you need it: The Pain Circuit

• Sensory receptors (nociceptors) respond to potentially damaging stimuli

• Send impulse to the spinal cord• Passes the message to the brain• Interprets the signal as pain

Gate Control Theory

• Draw it out!– Nociceptors– Endorphins– Distracted stimulation and control– Selective attention

• Pain meds and the Placebo Effect:• http://www.youtube.com/watch?v

=R4PON6Chgug

Phantom Limb

• Mirror box solution/experiment– http://www.youtube.com/watch?v=gc3CmS8_vUI

Pain and Biopsychosocial Approach

• What’s the conclusion to how pain is managed? What’s the nature of it, what’s the nurture of it?

– What’s the bio?– What’s the psycho?– What’s the social?