(17) Basal Ganglia Flashcards
putamen is seperated from the cuadate by the
internal capsule
function of the dorsal basal ganglia (or somatic basal ganglia)
movement control
function of the ventral (or limbic) basal ganglia
motivation, reward, and affect
the putamen is confluent with
the head of the caudate
what is at the rostral end of the tail of the caudate
amygdaloid nucleus
what is the midbrain continuation of the internal capsule
cerebral peduncle
what areas of the basal ganglia recieve axons from the substantia nigra to form DA terminals
head and tail of caudate and putamen
specifically, what part of the substantia nigra contains the DA neurons
pars compacta
**pars reticulata is just a network of neurons
the subthalamic nucleus is found above ___ and below ___
above the cerebral peduncle and below the thalamus
What are the 2 main types of neurons in the basal ganglia and what type predominates?
A and SN or aspiny and spiny neurons spiny predominate (95%)
major difference between spiny and aspiny neruons
spiny have a long axon that leaves the basal ganglia while aspiny have a short axon that do not
spiny = projection neurons aspiny = local circuit neurons
All spiny neurons use the NT…
GABA
How are the different subtypes of spiny neurons distinguished + 2 examples
type of neuropeptide they make
- ENK
- Substance P
ENK spiny neurons project to…
external GP
substance P spiny neurons project to
internal GP, para compacta > reticulata of the SN
where are subtance P and ENK spiny neurons intermingled
putamen and caudate
DA receptor type for ENK neurons
D2
DA receptor type for Substance P neurons
D1
function of striato-GPe
inhibit movement that conflicts with desired movement
**ENK
function of striato-GPi
promite limb movement
**SP
function of striato-SNr
promote eye movement
**SP
function of striato-SNc
regulate DA neurons
**SP
interneurons that are impervious to Huntington;s
somatostatin interneurons (and Cholinergic, and Calretinergic) = NOT paravalbuminergic
larger internurons
cholinergic and parvalbuminergic
What is the main NT for cholinergic interneurons
Ach
What is the main NT for parvalbuminergic interneurons
GABA
What is the main NT for somatostainergic interneurons
GABA and NO
What is the main NT for calretinergic interneurons
GABA
function of cholinergic interneurons
modulates peripheral nerves and opposes DA action
function od parvalbuminergic interneurons
inhibits peripheral nerves and sharpens activity
if there is insufficient DA (as in Parkinsons) inc or dec activity of cholinergic interneurons would help alleviate symptoms. why?
decrease bc cholinergic interneurons already oppose DA
major neuron type in the globus pallidus
aspiny
how are the dendrites of the aspiny neurons arranged in the globus pallidus?
in a vertical plane of the GP
the GPe projects neurons to
subthalamic nucleius
the GPi projects neurons to
ventral anterior and lateral nucleus of the thalamus
What part of the cortex does the VL project to?
motor cortex (4)
What part of the cortex does the VA project to
premotor (6)
What are the 3 major imputs to the putamen/caudate?
- cortex
- intralaminar thalamus
- SNc
corticostriatal neurons reside in layer ___ of the cortex
5
Where on the spiny neuron does the cerebral cortex neurons synpase and what NT is used
tip via glutamate
Where on the spiny neuron does the SN neurons synpase and what NT is used
sides via DA
look at sildes 30-33
I was too tired to continue
