Cerebellum

Question 1

What cells does the cerebellum contain?

Answer 1

Purkinje cells

Granule cells

Question 2

What is the structure of a purkinje cells

Answer 2

Huge, highly branched but flat dendritic arbor(axel).

Question 3

In the cerebellum the Purkinje cell are lined up like pages in a book, with their arbors lying in __ plane

Answer 3

parallel

Question 4

What two input do purkinje cells recieve

Answer 4

Weak inputs from parallel fibres
Strong input from a climbing fibre, a single axon which winds around the purkinje cell and makes multiple contacts with it.

Question 5

In response to multiple weak inputs from a parallel fibres what happens?

Answer 5

It fires a normal spike, or a simple spike

Question 6

A single spike from the climbing fiber is called what?

Answer 6

A complex spike

Question 7

What is the cerebellum import for?

Answer 7

Fine motor control and proprioception

There is a specific gait associated with cerebellar damage.

Question 8

It is believed that the connections from parallel fibers to Purkinke cells act as a perceptron. Thus if y is the output of the Purkinke cell and in this simple model taking in to account that Purkinje cells are inhibitory the equation is..

Answer 8

y= -sum(w_ix_i)
where xis are the activities in the parallel fibres and wi is the the strength of the synapse from the ith climbing fiber to the Purkinje cell.

Question 9

According to the perceptron rule there is a desired output d and the synapses are adjusted according to
dleta wi=-eta(d-y)xi

Answer 9

..

Question 10

What can synapses from parallel fibers only be?

Answer 10

Positive, this can be accounted for by including inhibitory cells in the network.