Basal Ganglia Flashcards
What brain are the basal ganglia in?
Forebrain
Where are the basal gangla found?
Towards base of brain, subcortical
Describe the pathway of the basal nuclei that initiates voluntary movement
- Ventral lateral (Vlo) nucleus
- Broadman’s 6 - supplementary motor cortex
- Projects back to basal nuclei
What makes up the striatum?
- Caudate nucleus
- Putamen
What makes up the lentiform nucleus?
- Putamen - darker
- Global Pallidius - paler (internal and external)
List the basal nuclei (5)
- Caudate nucleus
- Putamen
- Globus pallidus
- Substantia nigra
- Nucleus accumbens
Where is dopamine released from?
Substantia nigra pars compacta
Where does dopamine go to?
Striatum
What two things is the substantia nigra made of?
- Pars compacta
- Pars reticulata
What function does the nucleus accumbens have?
Function and reward
Give the pathway for direct pathway, facilitating wanted movement.
Cortex - striatum - (negative firing) - GPi (disinhibition) - thalamus (fires) - cortex
Give the pathway for indirect pathway, stopping unwanted movement
Cortex - striatum (inhibits) - GPe - (stops inhibiting) - subthalamus - (activates) - GPi (increased inhibition) - thalamus (less firing to) - cortex
What is Parkinson’s caused by?
Excessive inhibition of GPe - increased thalamus inhibition
What is Parkinson’s?
Trouble initiating wanted movement
What are the symptoms of Parkinson’s?
- Rigidity (increased muscle tone)
- Akinesia
- Bradycardia
