Basal Ganglia (new) Flashcards
what is the basal ganglia?
what is it involved in?
when does the basal ganglia become active?
Basal ganglia translates the idea of movement
into the motor expression of that idea.
involved in voluntary muscle movements and posture.
it comes active before a movement
the basal ganglia has these neurological structure components:
- Caudate nucleus
- Lentiform nucleus
- Claustrum
- Corpus Striatum
- Neostriatum
- Amygdaloid body
the basal ganglia has these basal nucleus for each neurological strucutre:
neurological structure / basal nucleus each structure
- Caudate nucleus = Caudate nucleus
- Lentiform nucleus = Globus pallidus + Putamen
- Claustrum = Claustrum
- Corpus Striatum = Lentiform + Caudate
- Neostriatum = Caudate + Putamen
- Amygdaloid body = Amygdaloid nucleus
basically the neurological can be 1 or 2 structures that get named together, the basal nucleus is each structure individually
identify
what do you get if you have a lesion of the splenium of the corpus callosum?
alexia withough agraphia
can’t read byt can write
identify
the basal ganglia divides into 2 pathways… what are these?
what happens when each gets activated?
1) direct: disinhibits thalamic motor nuclei (the ventral anterior and ventral lateral or VA and VL), resulting in cortical activation and movement initiation.
2) indirect: inhibits the VA and VL, resulting in reduction in cortical activation and movement suppression.
Name the afferent pathways going into the basal ganglia?
from where is each going to?
- Corticostriatal: Cortex to striatum
- Nigrostriatal: SNpc to various BG structures (and others).
- Amygdalostriatal: Amygdala to ventromedial caudate and putamen (suggests that BG may have limbic and non-limbic components).
- Thalamostriatal: From centromedian (and other) thalamic nuclei to striatum.
name the efferent (away form striatum) pathways going away from the basal ganglia?
- Striatopallidal: From striatum (caudate and putamen) to globus pallidus.
- Striatonigral: From striatum to substantia nigra.
- Ansa lenticularis: Globus pallidus to thalamus.
- Fasciculus lenticularis: Globus pallidus to subthalamus.
identify the blood supply to the basal ganglia
what is dyskenesia?
what is Hyperkinesia?
what is Hypokinesia?
- Movement disorders
- Involuntary spontaneous movements.
- Lack of spontaneous movement, and slowing of voluntary movement.
is there muscle weakness in basal ganglia disorders? Why?
no because there is no UMN or LMN damage
what are these Hyperkinetic Dyskinesia disorders:
- Chorea
- Athetosis
- Dystonia
- Ballismus
- Chorea: A series of rapid, jerky, involuntary movements.
- Athetosis: Continual uncontrolled writhing movements (disappear during sleep).
- Dystonia: A severe form of athetosis. Extreme contraction of antagonist muscle groups results in limbs locked in one position for long periods of time. Also may go in and out of muscle spasms.
- Ballismus: Involuntary flinging of limbs.
What is the most common hyperkinetic disorder originating in the basal ganglia?
Why does it happen?
Huntington’s Disease
loss of GABA enkephalinergic neurons in the striatum.
what can sometimes precede the development of involuntary motor movements?
What is the main symptom?
what can be seen in the brainstem with this disorder?
Dementia
Choreiform movements
Degeneration of caudate nucleus and subsequent
enlargement of ventricles.