Basal Ganglia ( Dara Cannon ) Flashcards
What is the Basal Ganglia involved in
Control of movement
What is involved in the disorder of BG
Abnormal motor control, posture and tone
What makes up of the nuclei of BG ( 3 )
- Striatum ( made up of caudate and putamen )
- Globus Pallidus
- Amygdala
What are the general connections of the BG
- Cerebral Cortex
- Thalamus
- Subthalamic Nucleus
- Substantia Nigra
What does the nucleus accumbent connect
It connects the rostral caudate to the putamen
What does the lateral medullary lamina separate
It separates the putamen and the globus pallidus
What does the medial medullary lamina separate
Separates GPi and GPe
How is the nucleus accumbens involved in reward and gratification
It is the site of action of addictive substances
What are the 5 components of the internal capsule
- ALIC
- PLIC
- Retrolenticular
- Sublenticular
- Genu
Where do you find the ALIC and what does it connect
Found between the caudate and putamen
Connects thalamus to cingulate and pons
Connects thalamus to frontal cortices
Where do you find the genu of IC and what does it connect
What tract does it include
Found at the inter ventricular foramen
Connects frontal cortex to pons
Connects thalamus VA and VL to the motor and premotor cortex
Includes corticobulbar tract
Where do you find the PLIC
What does it connect
What tract does it include
Between putamen and thalamus
Connects thalamus VA and VL w/ motor and premotor cortex
Connects VPL and VPM to post central gyrus
Contains corticospinal tracts
Where do you find the retrolenticular part of the IC
Posterior to the putamen
Contains fiber connecting thalamus to cortex ( optic radiations )
Contains parietal corticopontine fibers
Where do you find the sublenticular part of IC and what is it continuous with
Inferior to putamen
Continous w/ retrolenticular fibres and auditory radiations
What are the structures of basal ganglia from medial to lateral
Caudate and Thalamus Internal Capsule GPi Medial Medullary Lamina GPe Lateral Medullary Lamina Putamen External Capsule Clastrum Extreme Capsule Insular Cortex
Since the stratum is the input portion of the BG, it receives afferents from ( 5 )
Cerebral Cortex Thalamus Substantia Nigra VTA and raphe nuclei Striatal Efferents
Where do the corticostriatal fibres dominate
Where do the motor fibres go to
Is it excitatory or inhibitory
It dominates the frontal and parietal
Motor fibers go to putamen
Excitatory ( Glutamatergic )
What kind of fibres do the thalamus possess and where do they originate from
Possesses thalamostriatal fibers
Originates from the intralaminar nuclei
What kind of projections do the substantia nigra have and where do they originate from
They have nigrostriatal projections
The originate from the pars compacta of substantia nigra
With respect to VTA and raphe nuclei ;
Where do the dopaminergic input go to
Where do the serotonergic inputs go to
Dopaminergic goes to nucleus accumbens
Serotonergic foes to striatum
Are striatal efferents excitatory or inhibitory
Where do striopallidal efferents go to
Where do the striatonigral fibres go to
Inhibitory due to GABA
Goes to GPi or GPe
Goes to pars reticulate SN
What is the output portion of the globus pallidum
The globus pallidum
Where do the pallidal afferents come form
Are they excitatory or inhibitory
What are the name of the pathways ( 2 )
- Comes from the subthalamic nucleus
- Excitatory
- Subthalamonigral and Subthalamopallidal
Where do the Pallidal efferents go to
GPe goes to Subthalamic Nucleus
GPi and pars reticulata SN goes to brainstem tegmentum ( pedunculopontine ) and thalamus ( pallidothalamic )
