basal ganglia Flashcards
The corpus striatum is situated lateral to the thalamus and is almost completely divided by a band of nerve fibers
internal capsule
Globus pallidus plus putamen
Lentiform nucleus
Caudate nucleus plus lentiform nucleus
Corpus striatum
Caudate nucleus plus putamen
Neostriatum (striatum)
Amygdaloid nucleus
Amygdaloid body
large C-shaped mass of gray matter
caudate nucleus
large and rounded and forms the lateral wall of the anterior horn of the lateral ventricle
head of the caudate nucleus
- long and narrow and is continuous with the head in the region of the interventricular foramen
- forms part of the floor of the body of the lateral ventricle
body of the caudate nucleus
- long and slender and is continuous with the body in the region of the posterior end of the thalamus
- follows the contour of the lateral ventricle and continues forward in the roof of the inferior horn of the lateral ventricle
- terminates anteriorly in the amygdaloid nucleus
tail of the caudate nucleus
A vertical plate of white matter divides the nucleus into a larger, darker lateral portion
putamen
A vertical plate of white matter divides the nucleus into a inner lighter portion
globus pallidus
paleness of the globus pallidus is due to the presence of a high concentration of
myelinated nerve fibers
form the main sites for receiving input to the basal nuclei
caudate nucleus and the putamen
forms the major site from which the output leaves the basal nuclei
globus pallidus
Corpus Striatum Afferent Fibers
- corticostriate
- thalamostriate
- nigrostriatal
- brainstem striatal fibers.
- All parts of the cerebral cortex send axons to the caudate nucleus and the putamen
- Each part of the cerebral cortex projects to a specific part of the caudateβputamen complex
- Glutamate is the neurotransmitter
corticostriate fibers
of the thalamus send large numbers of axons to the caudate nucleus and the putamen
thalamostriate fibers
- send axons to the caudate nucleus and the putamen and liberate dopamine at their terminals as the neurotransmitter.
nigrostriatal fibers
- Ascending fibers from the brainstem end in the caudate nucleus and putamen and liberate serotonin at their terminals as the neurotransmitter
- inhibitory in function
brainstem striatal fibers
Corpus Striatum Efferent Fibers
striatopallidal and striatonigral fibers.
- pass from the caudate nucleus and putamen to the globus pallidus
- yβaminobutyric acid (GABA) as their neurotransmitter
striatopallidal fibers
- pass from the caudate nucleus and putamen to the substantia nigra
- use GABA or acetylcholine as the neurotransmitter, while others use substance P
striatonigral fibers
- pass from the caudate nucleus and putamen to the globus pallidus
- have GABA as their neurotransmitter
Globus Pallidus Afferent Fibers; Striatopallidal fibers
connected to the putamen
head of the caudate nucleus
connected to the caudate nucleus
amygdaloid nucleus
lies in the roof of the lateral ventricle.
tail of the caudate nucleus
terminates anteriorly in the amygdaloid nucleus
tail of caudate nucleus
All parts of the cerebral cortex send fibers to
the caudate nucleus and putamen
afferent corticostriate fibers to the corpus striatum
The neurons in the substantia nigra send axons
to the putamen
nigrostriatal fibers
Some of the striatopallidal fibers have GABA as
the neurotransmitter
efferent fibers of the corpus striatum
precede the activities of the motor cortex concerned with discrete movements of the hands and feet
globus pallidus
The caudate nucleus and the putamen form the
neostriatum
lies medial to the apex of the globus pallidus
internal capsule
basal nuclei are formed of ___
gray matter
lies lateral to the thalamus
corpus striatum
made up of the caudate nucleus and the lentiform nucleus
corpus striatum
divided into the head, body, and tail
caudate nucleus
forms part of the floor of the body of the lateral ventricle
body of the caudate nucleus
lies lateral to the anterior horn of the lateral ventricle
head of the caudate nucleus
neurotransmitter at the nerve endings of the corticostriate fibers to the corpus striatum
glutamate
neurotransmitter at the nerve endings of the nigrostriatal fibers
Dopamine
inhibitory in function
nigrostriatal fibers
caused by a reduction in the release of dopamine within the corpus striatum
Parkinson disease
pass from the caudate nucleus to the substantia nigra
striatonigral fibers