Cortex

Question 1

What are the 3 main areas of the auditory cortex?

Answer 1

• AI: primary auditory cortex
• AII: secondary auditory cortex
• Ep: posterior ectosylvian gyrus

Question 2

How many layers does the auditory cortex have? Is this the same or different as other cortical
sensory processing centers?

Answer 2

• 6

- Similar

Question 3

vMGB projects mainly to what layer of the auditory cortex?

Answer 3

-Layers III and IV

Question 4

Explain the neural connections in layer IV.

Answer 4

-Vertical columns that allow for soma-to-soma connections

Question 5

Explain the tonotopic organization of A1 and A2.

Answer 5

• AI: some single cells are sharply tuned to a single CF, multiple arrangements, iso-frequency strips
• AII: poor organization (cells in same region may have multiple CFs)

Question 6

What are two things that make measuring response properties and classification very difficult
in A1.

Answer 6

• Responses aren’t reliably collected/classified:
  
  • Habituation
  • Some neurons only fire while visually attending
  • Some neurons fire differently when awake vs. anesthetized

Question 7

Design a neuron with convergent inputs that has improved tuning.

Answer 7

-If 3 neurons (medial excitatory, laterals inhibitory) are connecting to a 4th neuron of the same CF as the medial, the 4th neuron will have enhanced tuning if one of the laterals is of a lower CF and the other is of a higher CF