Class

1
SENSORY MECHANISMS General Aspects and Terminology

• Some mechanisms are common elements for most
  types of sensation and perception. These
  eleements include
• The process of transduction
• The process of coding
• The relationship between stimulus and perception

Class 9 Sens Mech,Smell Taste, p. 1
2
SENSORY MECHANISMS Transduction
Class 9 Sens Mech, Smell Taste, p. 2
3
SENSORY MECHANISMS Coding
Class 9 Sens Mech, Smell Taste, p. 3
4
SENSORY MECHANISMS Coding (contd)
Class 9 Sens Mech, Smell Taste, p. 4
5
SENSORY MECHANISMS The relationship between
stimulus and perception
Cartoons associated with the case of Mr. Amadou
Diallo, an emigrant from West Africa, who,
returning home after work one evening in 1999,
was shot to death by undercover New York police
officers when he reached into his pocket to pull
out a small dark object. The police were were
looking for an armed rapist. The object turned
out to be Diallos wallet. Cartoons from the
following website cagle.slate.msn.com/news/diallo
/
Class 9 Sens Mech, Smell Taste, p. 5
6
SENSORY MECHANISMS The relationship between
stimulus and perception (contd)
Obviously, the answer is an emphatic
NO!! Perceptions are constructions by our CNS,
that are influenced by the nervous systems
ability to learn and its dynamic integration,
modulation, and flexible controls of stimulus
information. We will discuss some of these
abilities during class.
Class 9 Sens Mech, Smell Taste, p. 6
7
CHEMOSENSES SMELL (olfaction) and TASTE
(gustation)
Class 9 Sens Mech,Smell Taste, p. 7
8
CHEMOSENSES Olfaction
Class 9 Sens Mech, Smell Taste, p. 8
9
CHEMOSENSES Olfaction (contd)
Receptors

• Telereceptors
• Located in the nose
• The transduction part of the receptor looks like
  a dendrite with cilia
• 60 day life cycle
• more than 1,000 types

Class 9 Sens Mech, Smell Taste, p.9
10
CHEMOSENSES Olfaction (contd)
Class 9 Sens Mech, Smell Taste, p. 10
11
CHEMOSENSES Olfaction (contd) Routes of
information transfer through the CNS and
submodality coding
Cranial nerve I to the olfactory bulb (mitral
cells and glomeruli)
Submodality coding spatiotemporal pattern in
the glomuli of the olfactory bulb.
Class 9 Sens Mech, Smell Taste, p. 11
12
CHEMOSENSES Olfaction (contd) Routes of
information transfer through the CNS
(1) Cranial nerve I ? olfactory bulb (mitral
cells glomeruli) (2) From olfactory bulb to
parts of paleocortex in the telencephalon,
including the ? Amygdala (emotions)
? Entorhinnal, pyriform, orbitofrontal
cortex. (3) From there the information goes to
? Hypothalamus (emotions, motivations),
? Hippocampus (in temporal lobe memory)
Class 9 Sens Mech, Smell Taste, p. 12
13
CHEMOSENSES TASTE
Class 9 Sens Mech, Smell Taste, p. 13
14
CHEMOSENSES TASTE (contd)
Umami? Carbohydrate? Glutamate?
Class 9 Sens Mech, Smell Taste, p. 14
15
CHEMOSENSES TASTE (contd)
Class 9 Sens Mech, Smell Taste, p. 15
16
CHEMOSENSES TASTE (contd) Routes of information
transfer through the CNS
Class 9 Sens Mech, Smell Taste, p. 16
17
CHEMOSENSES TASTE (contd) Routes of information
transfer through the CNS
Class 9 Sens Mech, Smell Taste, p. 17
18
Dont forget! I strongly encourage you to read
Module 7.3 (p. 215-227) thoroughly. It contains
loads of interesting information about smell and
taste as well as pheromones and synesthesia!
Class 9 Sens Mech Taste Smell., p. 18