Week 14 Flashcards
(37 cards)
Dolarimeter
Focused beam of light that caused pain- can quantify/control. Other methods include putting hand in bucket of ice water
Pain adaptation
Varies with intensity of painful stimulus. Weber’s function:4%. M=3.5 for scaling (dol scale)
Placebo effect
fMRI imaging studies show placebos decrease brain activity in pain sensitive areas of brain including thalamus, insult, and anterior cingulate cortex
Psychological pain
“Pain” associated with social rejection. fMRI studies show that human brain area “light up” for physical pain (anterior cingulate) is activated by social loss. More social distress, more strongly anterior cingulate activated. Activity in prefrontal cortex linked to low social distress
Papillae
Bumps on tongue that contain taste buds
Taste buds of papillae
Fungi form, foliate, circumvallate, filiform
Taste
Goes through microvilli in tongue pores in taste buds in papilla
Salt
Opens up channels on microvilli
Sweet, bitter, umami
Sends G protein to send signal to open channels
Taste receptors front to back
Fungi form, foliate, circumvallate
Order
Tongue, thalamus, orbitofrontal cortex
Neuronal transmission
Salts directly depolarize gustatory cells by opening
How do neurons encode taste info?
Taste intensity related to rate of neuronal firing (logarithmic). Taste quality signaled by primary divers (labeled line). Some respond to everything (across taste)
Taste thresholds
Affected by concentration of solution, temp, viscosity, state of tongue
Taste adaptation
Tongue quickly adapts to taste substances and this can raise threshold
Self adaptation
Prior exposure to a taste raises threshold for subsequent exposure to that taste.
Cross-adaptation
Prior exposure to a taste raises threshold to subsequent exposure of a different taste, but only to extent that 2 tastes are chemically similar
Potentiation
Prior exposure ton1 taste primary can lower threshold to subsequent primary. Sweet things enhance sourness of sour things
Taste adaptation
Neural phenomenon
Taste discrimination
Not good. Webers function is high (0.1-1.0) and variable. Even worse in elderly
Taste scaling
Magnitude estimation is fairly accurate for most primaries (n=1) but testing conditions and adaptation play big role. Multidimensional scaling is useful for describing complex food tastes
Olfactory epithelium
Smell receptor
Orthonasal olfaction
Comes in through nose
Retronasal olfaction
Comes in through mouth
