PSY 437 Sensation and Perception
Knapp
Study Guide 31
Chemical Senses
Goldstein pps. 356-375
Today we take a look at taste, smell, and flavor. The first question is review from the study guide
on touch.
1. What is chemoreception?
a. transducing chemical stimulation
2. What is neurogenesis?
a. Generation of neurons
3. Why is it important that chemoreceptors experience regular neurogenesis?
a. Because chemoreceptors are regularly exposed to nasty chemicals and other environmental
hazards. In other words, they’re getting killed a lot.
4. What's the difference between macrosmatic and microsmatic organisms and are humans
macro- or microsmatic?
a. Macro- strong sense of smell
b. Micro- weak sense of smell
c. Humans have horrible senses of smell compared to many other species.
i. We’re microsmatic
5. Approximately how many odors can neurologically intact humans discriminate between?
a. About 100,000, although we can’t identify all 100,000
6. How many odors can individuals with anosmia discriminate between?
a. 0: they can’t smell anything
7. What are pheromones and what evidence is there that humans produce and respond to
pheromones?
a. Chemical messengers that we aren’t necessarily consciously aware of.
b. Women’s menstrual cycles start to sync with thedominant female.
8. What is a forced-choice procedure and how does it overcome a person’s bias to respond yes
or no?
a. Procedure in which people have a limited number of responses.
b. Can avoid people saying I don’t know.
PSY 437 Sensation and Perception
Knapp
Study Guide 31
9. How well can people recognize objects by smell compared to objects by sight?
a. Pretty poorly
10. Are the differences in recognition due to a sensory problem or a memory problem and how
could one tell?
a. When we find out the identity of a smell we can’t identify and recognize the identity is
correct, we know there was a memory problem.
11. Describe how people smell. Make sure you use the following terms.
a. Odorant
i. Chemicals we can smell
b. Olfactory Mucosa
i. Mucus covered site where olfactory receptors are
c. Olfactory Receptors
i. Receptors for the chemicals we can smeel
d. Cribriform plate (this is the bone that separates the mucosa from the brain)
i. Holey bone through which the axons of of the receptors pass to reach the
glomeruli.
e. Glomeruli (plural of glomerulus)
i. Nuclei where particular smells are processed/represented in the olfactory
bulb
f. Olfactory bulb
i. Structure containing all the glomeruli
g. Piriform Cortex
i. Primary olfactory cortex
h. Orbitofrontal cortex
i. Secondary olfactory cortex
i. Amygdala
i. Fear and emotional center with lots of olfactory inputs
12. How are smells represented by the brain? That is, how do we know we're smelling roses and
not crap.
PSY 437 Sensation and Perception
Knapp
Study Guide 31
a. Different patterns of activation.
13. What is gustation?
a. Sense of taste
14. What are the 5 basic taste qualities and what foods are good examples of the different types
of taste.
a. Sour
b. Sweet
c. Salty
d. Bitter
e. Umami
15. Describe how people taste. Makes sure you use the following terms.
a. Stimulus
i. Chemicals
b. Papillae
i. Structures where tastes are transduced
ii. Filiform
1.
iii. Fungiform
iv. Foliate
v. Circumvilliate
c. Taste buds
i. On papillae where transduction takes place
d. Taste cell
i. The actual cells that transduce the signal
e. Taste pore
i. Opening in taste bud where transductive ends of cells are located
f. Nucleus of the solitary tract
i. First stop for taste information
PSY 437 Sensation and Perception
Knapp
Study Guide 31
g. Insula
i. Gustatory cortex
h. Orbitofrontal Cortex
i. Flavor cortex
16. How are tastes represented by the brain? (How do we know we're tasting something salty
instead of something bitter)
17. What is flavor?
a. Combination of taste and smell
18. What part of the brain is responsible for processing flavor information?
a. Orbitalfrontal