Lecture 13: Outline 1. Gustatory system organization 2. Taste ...

Lecture 13: Outline
1. Gustatory system organization
2. Taste receptors and signal transduction
3. Central gustatory projections
4. Encoding of taste stimuli
Readings: Text, Chapter 15

Figure 15.15 The human taste system

Figure A7 The locations of the cranial nerves as they enter or exit the midbrain, pons, and medulla
Some neuroanatomy…

Figure A8 Brainstem cranial nerve nuclei locations that are the target or source of cranial nerves
MIDDLE MEDULLA

Figure 15.16 Taste buds and the peripheral innervation of the tongue
The distributions of taste receptor types in
the tongue and rear oral cavity differ, as
does the sensitivity to each kind of tastant
Figure 15.17 Taste buds, taste cells, and taste transduction

Figure 15.18 Taste transduction via ion channels and G-protein–coupled receptors (Part 1)
Transduction mechanisms vary with taste quality

Figure 15.19 Specificity in peripheral taste coding supports the labeled line hypothesis
The encoding of taste
sensations in the
periphery into separate
parallel channels is
maintained at each
level of the taste
pathways, all the way
to the insular cortex.
Afferent fibers receive
synaptic inputs from only one
type of chemoreceptor