Week 5

Question 1

86…

How many neurons are in the human brain?

Answer 1

There are approximately 86 billion neurons in the human brain

Question 2

CC = 81%, 19% = TBN

What percentage of brain mass and total brain neurons does the cerebral cortex contain?

Answer 2

The cerebral cortex contains 81.2% of brain mass and 19% of total brain neurons

Question 3

3 L, 3 F SubD, 3 P of Pe, 3 P of DN, 3 CL

What is the rule of 3 in the cerebellum?

Answer 3

The cerebellum contains 3 lobes, 3 functional subdivisions, 3 pairs of peduncles, 3 pairs of deep nuclei, and 3 cortical layers.

Question 4

What are the primary functions of the cerebellum?

Answer 4

The primary functions of the cerebellum are movement coordination, maintenance of posture, maintenance of muscle tone/balance, and motor learning

Question 5

What are the consequences of cerebellar damage?

Answer 5

Cerebellar damage causes severe movement disruption, such as ataxia, which is characterized by a lack of coordination

Question 6

What are the major components of the cerebellum?

Answer 6

The major components of the cerebellum are the cerebellar peduncles (superior, middle, inferior), cerebellar cortex (cerebrocerebellum, spinocerebellum, vestibulocerebellum), and deep cerebellar nuclei (dentate, interposed, fastigial)

Question 7

What are the inputs and outputs of the superior cerebellar peduncle?

Answer 7

The superior cerebellar peduncle has no inputs and outputs to the motor cortex (via thalamus) and red nucleus

Question 8

What are the inputs and outputs of the middle cerebellar peduncle?

Answer 8

The middle cerebellar peduncle receives inputs from the motor cortex (via pons) and has no outputs

Question 9

What are the inputs and outputs of the inferior cerebellar peduncle?

Answer 9

The inferior cerebellar peduncle receives inputs from the inferior olivary nucleus, spinal cord, and vestibular nuclei, and outputs to the reticular formation (brainstem), spinal cord, and vestibular nuclei

Question 10

What is the cerebrocerebellum responsible for?

Answer 10

The cerebrocerebellum is involved in motor planning and projects to and from the cerebral (motor) cortex

Question 11

What is the spinocerebellum responsible for?

Answer 11

The spinocerebellum regulates body and limb movements and receives somatic sensory inputs that exhibit somatotopy

Question 12

What is the vestibulocerebellum responsible for?

Answer 12

The vestibulocerebellum, also known as the flocculonodular lobe, regulates balance and eye movements

Question 13

What are the principal elements of cerebellar neural circuitry?

Answer 13

The principal elements are mossy fibers, granule cells, climbing fibers, Purkinje cells, and parallel fibers

Question 14

What is the function of Purkinje cells in the cerebellum?

Answer 14

Purkinje cells have an inhibitory function and are the exclusive output of the cerebellar cortex, projecting to the deep cerebellar nuclei

Question 15

How do climbing fibers contribute to motor learning?

Answer 15

Climbing fibers excite Purkinje cells directly and are believed to sense error signals to elicit learning, contributing to motor learning

Question 16

What is the conditioned eye-blink response?

Answer 16

The conditioned eye-blink response is an example of cerebellar sensorimotor learning where a neutral stimulus (CS) is paired with an aversive stimulus (US), eventually causing the CS to elicit a conditioned response (CR).

Question 17

What is the Marr-Albus-Ito hypothesis?

Answer 17

The Marr-Albus-Ito hypothesis suggests that simultaneous activation of climbing fibers and mossy fibers causes long-term changes in parallel fiber to Purkinje cell synapses, resulting in long-term depression (LTD) and increased output of deep cerebellar nuclei

Question 18

What are the main functions of the cerebellum?

Answer 18

The main functions of the cerebellum are movement coordination, posture and balance, and motor learning

Question 19

What is the overall function of the basal ganglia?

Answer 19

The basal ganglia are involved in the strategic aspects of movement, behavior, and emotion. They have widespread reciprocal connections to the cerebral cortex but no direct connections to the spinal cord

Question 20

Cau, Put, Glo Pal, SubT N, Sub Ni

What are the main components of the basal ganglia?

Answer 20

The basal ganglia consist of five nuclei: Caudate, Putamen, Globus Pallidus (internal and external), Subthalamic Nucleus (STN), and Substantia Nigra.

Question 21

Involves 2 Inh Syn resulting in DisH, Fac Mov. Inc exc NT like Glu & ..

Describe the direct motor pathway of the basal ganglia

Answer 21

The direct pathway involves two inhibitory synapses resulting in disinhibition, thereby facilitating movement. It includes excitatory neurotransmitters like glutamate and inhibitory neurotransmitters like GABA

Question 22

Involves Exc of Inh, Sup Mov. Inc STN as relay from St to GPI/SNr

Describe the indirect motor pathway of the basal ganglia

Answer 22

The indirect pathway involves excitation of the inhibition, thereby suppressing movement. It includes the Subthalamic Nucleus (STN) as a relay from the striatum to the GPi/SNr.

Question 23

D from SNc Exc direct P(D1) & Inh indirect P(D2), both = Fac Mov

How does dopamine affect the basal ganglia pathways?

Answer 23

Dopamine from SNc excites the direct pathway via D1 receptors, and inhibits the indirect pathway via D2 receptors, both actions facilitate movement

Question 24

Increased A of Ind P % Dec A of Dir P, Causing Mov Sup

What are the effects of Parkinson’s disease on the basal ganglia?

Answer 24

Increased activation of the indirect pathway & decreased activation of the direct pathway, causing movement suppression

Question 25

Dec A of Ind P, Inc A of Dir P, Causing Mov Fac

What are the effects of Huntington’s disease on the basal ganglia?

Answer 25

Decreased activation of the indirect pathway and Increased activation of the direct pathway, Causing movement facilitation

Question 26

GPi and SNr are O C of basal ganglia

What is the role of the Globus Pallidus internal (GPi) and Substantia Nigra pars reticulata (SNr) in the basal ganglia?

Answer 26

The GPi and SNr are the output centers of the basal ganglia

Question 27

Result in errors in I & T mov, leading to

How does damage to the basal ganglia affect movement?

Answer 27

Can result in problems initiating and terminating movement, leading to physical conditions