basal ganglia

Question 1

function of basal ganglia

Answer 1

• motor functions
• non-motor functions

Question 2

motor functions of basal ganglia

Answer 2

• action selection
• inhibition of competing movements
• enabling motor programs

Question 3

non-motor functions of basal ganglia

Answer 3

• cognition and emotion
• reward and addiction

Question 4

basal ganglia pathology

Answer 4

• movement disorders (hypokinetic and hyperkinetic)
• cognitive and neuropsychiatric symptoms

Question 5

inputs to motor cortex (area 4)

Answer 5

basal ganglia work through motor cortex
- thalamic nuclei (VA and VL)
- premotor cortex (area 6)

then descend!

Question 6

basal ganglia pathway

Answer 6

• motor cortex signals down pyramidal tract to alpha motor neuron
• association, sensory, and motor cortex signal to basal ganglia
• basal ganglia to VA and VL
• VA and VL to motor cortex

Question 7

parts of basal ganglia

Answer 7

• caudate and putamen (basically 1 nucleus)
• globus pallidus

Question 8

the internal globus pallidus

Answer 8

• send inhibitory signals the thalamus

Question 9

the caudate and putamen function to

Answer 9

inhibit the globus pallidus

Question 10

the caudate and putamen together can be called

Answer 10

neostriatum

Question 11

brain section

Answer 11

Question 12

brain section zoomed in to see caudate and globus pallidus

Answer 12

Question 13

associated nuclei (in midbrain)

Answer 13

• substantia nigra
• subthalamic nucleus

Question 14

substantia nigra

Answer 14

• reciprocally connected to caudate and putamen
• dopaminergic projection to striatum

Question 15

subthalamic nucleus

Answer 15

• reciprocally connected to globus pallidus

Question 16

Pathology of basal ganglia

Answer 16

• Parkinson’s
• Chorea and Athetosis
• Ballismus
• Dystonia

Question 17

Parkinson’s disease is caused by

Answer 17

loss of dopamine in the substantia nigra; degeneration of the SN

Question 18

Parkinson’s Disease symptoms

Answer 18

• tremor at rest (“pill rolling tremor”)
• rigidity
• bradykinesia (slow mvmt)
• motor blocks (“freezing”)
• loss of postural reflexes (tend to fall, shuffling feet)
• cognitive defects are common

Question 19

definition of rigidity

Answer 19

• excess tone in all directions. Not just against gravity.
• Called lead pipe rigidity

Question 20

spasticity occurs in

Answer 20

antigravity muscles that show excess tone

Question 21

the neurons in substantia nigra are

Answer 21

dopaminergic

Question 22

Pathways of dopamine formation

Answer 22

Question 23

treatments for Parkinson’s

Answer 23

• L-dopa given to patient
• DOPA is a precursor to dopamine so this can help increase dopamine production

Question 24

Huntington’s Chorea cause and symptoms

Answer 24

cause:
- degeneration in caudate nucleus
symptoms:
- excess movements
- autosomal dominant (genetic)

Question 25

Ballismus cause and symptoms

Answer 25

cause: damage to subthalamic nucleus symptoms: ballistic movements

Question 26

athetosis symptoms

Answer 26

- excess movements - writhing (twisting) movements

Question 27

other basal ganglia disorders

Answer 27

- dystonia - tics - tourette syndrome

Question 28

role of basal ganglia in motor function

Answer 28

- normally suppresses inappropriate motor program - activation of direct pathway temporarily releases one motor program from inhibition - also involved in learning of motor programs

Question 29

ventral tegmental area (VTA)

Answer 29

- dopaminergic projections to prefrontal cortex and limbic cortex (selection of emotional, executive, and cognitive programs) - dopaminergic projections to nucleus accumbens (reward and addiction)