3 Senses - Taste, Touch, and Smell

Olfaction

the act of smelling (a chemical sense)

Olfactory Receptor Cells

in nose, where chemical molecules of odors latch onto; transduce

thalamus

olfaction doesn’t go through what?

receptors transduce, olfactory bulb, olfactory nerve, primary smell cortex (temporal lobe)

pathway of olfaction

memories/ emotions

Odors evoke…

Olfactory bulb

part of limbic system connected to amygdala and hippocampus which help smell evoke memories/ feelings

Gustation

the act of tasting (chemical sense)

sweet, salty, sour, bitter, umami

5 tastes (different from multitude of flavors!)

taste buds

collect chemicals with receptor cells! Reproduced every 1-2 weeks, so ppl preferences change (for something to be tasted, it must dissolve on these) - transduce chemicals in food

taste buds transduce, facial nerve, medulla, thalamus, primary gustatory region

pathway of taste

Seonsory interaction

the principle that senses may work together/ influence each other

McGurk Effect

vision and audition work together (lip reading/ written words impact what hear)

Flavor

the combination of odor, texture, temp, and taste

Taste blindness

lack of sensitivity to certain tastes (ex. cilantro/ stick paper test thingy - can be genetic)

Touch

the combination of pressure, temperature, and pain - what the skin senses

Pressure

has special nerves to sense

temp/pain

have more common/ plentiful nerves throughout the skin

seeing/ not seeing

touch or sound (echolocation) can help us to visualize objects without sight

AB nerves (alpha-beta)

insulated sensory neurons with a myelin sheath that are able to quickly transmit messages to the brain

C nerves

unmyelinated sensory nerves that feel pain and transmit the message slower

Gate-Control Theory

activating AB nerves (using ice pack, massaging) can reach the brain quicker after injury to suppress slower c nerves (like if you get bruised).

gate / genetic diff in endorphins

biological explanation for pain

selective attention / expectation / experience

psychological explanation for pain

peer pressure / society expectations

socio-cultural explanation for pain

Kinesthesis / Proprioception

the system for sensing your body position even without other senses

Proprioceptors

help to sense body position (transduce)

prioprioceptors, nerves, spinal cord, cerebellum

pathway for kinesthesis

Vestibular sense

awareness of balance in order to move smoothly using head position (when balanced, the fluid in ear is level)

hair cells pick up on fluid, vestibular nerve, cerebellum

pathway for vestibular sense