40 Basal ganglia Flashcards
(Neo)Striatum = ________ + _______?
Putamen + Caudate nucleus
Lentiform nucleus = ________ + _______?
Putamen + Globus pallidus
Corpus striatum = ?
Putamen + caudate nucleus + globus pallidus
______________ separates the thalamus and caudate nucleus on the medial side, and the putamen and globus pallidus on the lateral side.
Internal capsule
Internal capsule separates _________________ on the medial side and the putamen and globus pallidus on the lateral side.
thalamus and caudate nucleus
Internal capsule separates the thalamus and caudate nucleus on the medial side, and ____________ on the lateral side.
Globus pallidus and putamen
Which of the following are parts of the basal ganglia? A. Neostriatum B. Substantia nigra C. Subthalamic nucleus D. Amygdala E. Lentiform nucleus F. Red nucleus
All except D and F
they are neighboring structures - VTA - geniculate bodies - hypothalamus etc.
In coronal section, where is the red nucleus located relative to the thalamus and substantia nigra?
In between,
inferior to thalamus, superior to substantia nigra
In coronal section, where is the caudate nucleus relative to the thalamus?
more superior and lateral to the thalamus
Which part of the substantia nigra is more lateral in the midbrain?
Reticular part is more lateral than the compact part
Arrange from medial to lateral, the position of subthalamic nucleus, substantia nigra and the red nucleus in the midbrain-diencephalon junction.
red nucleus > subthalamic nucleus > substantia nigra compact part > substantia nigra reticular part
Afferent connections of the striatum?
- corico-striae
- nigro-striae (substantia nigra)
- thalamo-striae
Efferent connections of the striatum?
- Strio-nigral
2. Strio-pallidal
Afferent connections of the globus pallidus?
- Strio-pallidal
2. Subthalamic fasciculus (from subthalamic nucleus to GP)
Efferent connections of the globus pallidus?
- Subthalamic fasciculus (from GP to subthalamic nucleus)
- Thalamic fasciculus (travel in front of red nucleus)
- lenticular fasciculus (GPi > thalamus)
- ansa lenticularis (subthalamic nucleus + GPi > thalamus)
In the thalamus _________ and _________nuclei receive afferents from globus pallidus and project to the frontal cortex.
ventral anterior and ventral lateral nuclei
_______________ nuclei in the thalamus receive afferents from the ARAS (ascending reticular activating system) and project to the striatum.
Intralaminar nuclei
DA projections from SNc ________ striatum neurons that have D1 receptors.
excite
DA projections from SNc ________ striatum neurons that have D2 receptors.
inhibit
What is the NT involved in subthalamic nucleus and what is its effect?
Glutamine, to GPi and SNr
Give the 3 functions of connections of the basal ganglia.
- Initiation: response occurs to initiate a movement
- Selection and sequencing: motor areas interact with basal ganglia to select muscle activities by disinhibition for the required movement, and arrange them in order
- Output: returns a plan to specific cortical area for the required movement
Suggest 3 alterations from other parts of the brain to the basal ganglia.
- Limbic system: affect striatum
- Thalamostriatal projection: thalamus affected the striatum, initiate a pause in activity, enable switching from an ongoing behavior to another one
- ARAS: affect thalamus
Reason for hypokinesia?
Degradation at the substantia nigra compacta, increased output from SNr and Gpi
(indirect > direct loop)
Reason for hyperkinesia?
- Degradation of the subthalamic nuclei > decreased inhibitory outputs from GPi and SNr.
- Affected D2 neurons
Symptoms in cerebral palsy?
- Athetosis (ceaseless slow, sinuous movements especially in hands)
- Dystonia (increased muscle tone and abnormal fixed postural of trunk and limbs)
What is Tourette syndrome?
- physical and vocal tics (repetitive, stereotyped, involuntary movements and vocalizations called tics)
- Minority: foul utterance
Features of __________:
- dominant inheritance
- Choreoathetosis
- Dementia
Huntington’s chorea
