1. Clinical Correlations
Basal Nuclei
Connections
And
Clinical Correlations

2. Clinical Case 1
David is a 66-year-old man, previously healthy, who was brought to a neurologist by his daughter because of increasing difficulty in walking. His daughter noticed that for the past year, he had difficulty getting out of a chair and took a lot of time to begin to walk. When he did walk, he walked with a slow, shuffling gait. In addition, she had noticed some changes in his face, and that he had been drooling excessively. His signature on checks became progressively smaller from the beginning of his name to the end, and he had developed a new tremor. She brought him in to make sure this wasn’t just “aging.” The neurologist examined David and noticed immediately that David facial expression was masklike, with few eye blinks. When asked to write a sentence, the letters became progressively smaller toward the end of the sentence

3. Case Cont… His speech was soft and monotonous, and he had a slow,
resting pill-rolling tremor in both of his hands. He had very little spontaneous movement, and his arms, legs, and trunk were stiff. When the neurologist tried to flex his arm, he felt many catches, similar to a cogwheel. There was no weakness, sensory problems, or abnormalities in his reflexes. When asked to walk, David took many tries to rise from his chair. When he finally stood up, his posture was stooped and flexed. His gait was slow, his feet shuffled when he walked, and his arms didn’t swing with his steps. The neurologist told David daughter that she was correct that this wasn’t aging and explained to her all of the details about a new medication that David needed to take.

4. Clinical Case 2
A 55 year-old Tennis player noticed the abrupt onset of involuntary movements on his right side. His right arm would make large, violent, flailing or ballistic movements that interfered with his game. The most likely site of the damage was the:
Left substantia nigra
Left globus pallidus
Right globus pallidus
Right subthalamic nucleus
Left subthalamic nucleus

5. Clinical Case 3
Hyperkinetic syndromes such as ballism, Athetosis and chorea are related to a problem of thalamic disinhibition related to which of the following neurotransmitters.
Dopamine
Gamma aminobutyric acid
Acetylcholine
Dopamine and gamma aminobutyric acid
Substance “p”and enkephalin

6. Clinical Case 4
77-year-old man is finding that he has more difficulty moving about for the past year. He is annoyed by a tremor in his hands, but the tremor goes away when he performs routine tasks using his hands. His friends remark that he seems more sullen and doesn't smile at them, but only stares with a fixed expression on his face. He has not suffered any loss of mental ability. Which of the following diseases is he most likely to have?
Alzheimer disease
Parkinson disease
Cerebellar Disease
None Of above

7. Basal Ganglia Gross Features
It is a nuclear mass located within the depths of each cerebral hemisphere.
Corpus Striatum
Claustrum
Amygdaloid body
The corpus striatum is the largest component of the basal ganglia.
Divided into three components.
It includes the caudate nucleus, the putamen and the globus pallidus.
The caudate nucleus (CD) is a large C-shaped grey matter located medial to the internal capsule and related throughout its length to the surface of the lateral ventricle.

10. Basal Ganglia Gross Features
It has an head that bulges into the lateral wall of the frontal horn of the lateral ventricle.
The head tapers to form the body located along the lateral wall of the ventricle.
The body in turn becomes further (Continued) attenuated to form the tail which courses along the roof of the temporal horn of the ventricle and terminates at the amygdaloid nucleus.
Amygdaloid Nu

11. Basal Ganglia Gross Features
The PU and CD together comprise the neostriatum (neo = new) which is sometimes simply abbreviated striatum.
Histologically, the structure of the CD and PU are similar.
They contain the inhibitory neurotransmitter gamma-amino butyric acid (GABA).

12. Basal Ganglia Gross Features
The paleostriatum (paleo = ancient ) or "pallidum" is the forerunner of the mammalian corpus striatum and consists of the globus pallidus (GP) only.
The GP is situated medial to the putamen and is separated from it by a thin lamina of myelinated fibers called the external medullary lamina.
A similar lamina (medial medullary lamina) divides the GP into a lateral or external division (GPe) and a medial or internal (GPi) division, each of which has its own peculiar set of connections.
The GP is traversed by numerous myelinated fibers which give it its characteristic pale appearance in stained sections and from which its name derives.

13. Basal Nuclei Connections

16. Dopamine and Cholinergic Effect

17. Basal Ganglia Connections
Primary
Motor Area
(M I)
Supplementary
Motor Area
(SMA)
STRIATUM
(Putamen)
pyramidal
tract
ansa
lenticularis
THALAMUS
(VLo, VApc, CM)
PALLIDUM
(GPi)
lenticular
fasciculus
LMN

18. SNr Basal Ganglia Connections Primary Motor Area (M I) Prefrontal
Association
Cortex
STRIATUM
(Caudate
Nucleus)
pyramidal
tract
THALAMUS
(VLm, VAmc, MD)
SNr
(Substantia Nigra,
pars reticulata)
LMN

19. Motor Cortex Striatum VA-VL complex GP, SNr
Basal Ganglia (Microcircuitary) Connections
glutamate +
Motor
Cortex
Striatum +
glutamate
glutamate +
GABA
VA-VL
complex
GP, SNr -
GABA

20. Organization of the motor system
Level 1
Cerebral cortex motor areas
1. The elements
Basal Ganglia
Level 2
Thalamus
2. Three levels
Cerebellum
Brain Stem
3. Feedback loops between and within levels.
Muscle contraction and Movement
Spinal Cord
Level 3
Sensory receptors

21. Disorders Of Basal Ganglia
Hyperkinetic
Chorea, Athetosis & Ballism
Hypokinetic
Akinesia &Bradykinesia

22. SYDENHAM’S CHOREA Clinical Feature - Complication of Rheumatic Fever
- Fine, disorganized , and
random movements of
extremities, face and
tongue
- Accompanied by
Muscular Hypotonia
- Typical exaggeration of
associated movements
during voluntary activity
- Usually recovers
spontaneously
in 1 to 4 months
Principal Pathologic Lesion: Corpus Striatum

23. Principal Pathologic Lesion:
HUNTINGTON’S CHOREA
Clinical Feature
- Predominantly autosomal dominantly
inherited chronic fatal disease
(Gene: chromosome 4)
- Insidious onset: Usually 30-50
- Choreic movements in onset
- Frequently associated with
emotional disturbances
- Ultimately, grotesque gait and sever
dysarthria, progressive dementia
ensues.
Principal Pathologic Lesion:
Corpus Striatum (esp. head of caudate nucleus) & Cerebral Cortex

24. HEMIBALLISM Clinical Feature Lesion: Subthalamic Nucleus
- Usually results from CVA
(Cerebrovascular Accident)
involving subthalamic nucleus
- sudden onset
- Violent, writhing, involuntary
movements of wide excursion
confined to one half of the body
- The movements are continuous
and often exhausting but cease
during sleep
- Sometimes fatal due to exhaustion
- Could be controlled by
phenothiazines and stereotaxic
surgery
Lesion: Subthalamic Nucleus

25. Disease of mesostriatal
Parkinson’s Disease PD
Disease of mesostriatal
dopaminergic system
normal
Muhammad Ali in Alanta Olympic

26. Parkinson’s Disease - Paralysis Agitans
Substantia Nigra,
Pars Compacta (SNc)
DOPAminergic Neuron
Clinical Feature (1)
Slowness of Movement
- Difficulty in Initiation and Cessation
of Movement

27. Parkinson’s Disease Paralysis Agitans
Clinical Feature (2)
Resting Tremor
Parkinsonian Posture
Rigidity-Cogwheel Rigidity