Basal Ganglia GT

Fornix, mamillary bodies, cingluate gyrus, hypocampus, anterior thalamic nuclei =

memory

Parahippocampal gyrus contains

hippocampus

What is the primary function of the basal ganglia

Primary motor coordination (within muscle) center; coordinated balanced smooth motion

Overall and simplified, what is the objective of the direct pathway

wanted movement for tasks

Overall and simplified, what is the objective of the indirect pathway

inhibit unwanted movements for tasks

What is the net outome of dopamine when it is released from the subtantia nigra pars compacta to dopa-r on striatum

Dopamine will always want to end in movement. Dopamine is the lubricant of movement = greaser of the wheel

What is the “homeplate”, of the basal ganglia

motor cortex

What are the GLUTAMATE releasing structures of the BG

Motor cortex, thalmus, subthalmus

What are the GABA releasing structures of the BG

Striatum (caudate nucleus and putaman), globus pallidus medial/lateral, and substantia nlgra pars reticularis

What is the DOPAMINE releasing structure of the basal ganglia

Substantia Nigra Pars Compacta

What is the ORDER the neurons run (synapse) in the DIRECT pathway

What is the ORDER the neurons run (synapse) in the INDIRECT pathway

Generally speaking, what is the BG structure that suffers degeneration with Huntington’s Disease

Striatum

Generally speaking, what is the BG structure that suffers degeneration with Parkinson’s Disease

Substantia Migra Pons Compacta

What is the effect of the motor cortex on the striatum in the DIRECT AND INDIRECT pathway

Motor cortex releases glutamate to stimulate striatum

DIRECT PATHWAY

What is the effect of the Striatum on the Globus Pallidus Medial

Inhibit Globus Pallidus with GABA

DIRECT PATHWAY

What is the effect of the Striatum on the Subst Nigra Pars Ret

Inhibit SNPR with GABA

DIRECT PATHWAY

What is the effect of the GPm and SNPR on the Thalamus

less inhibition so thalamus can secret more glutamate

DIRECT PATHWAY

What is the effect of the thalamus on the motor cortex neurons

promotes the movement

INDIRECT PATHWAY

What is the Globus lateral effect on the subthalamus of the indirect pathway?

Releases GABA to inhibit subthalmus but in the indirect pathway it is inhibited so the subthalamus can release more glutamate

INDIRECT PATHWAY

What is the effect of the subthalamus on the GPmed

In the indirect pathway the subthalamus releases more glutamate and stimulates the globus palitus medial; subthalamus releases glutamate

INDIRECT PATHWAY

How does the GPmed affect the thalamus in the indirect pathway

In the indirect pathway the GPmed releases more GABA and inhibits the thalamus; GPmed releases GABA

What is the result of the thalamus on the motor cortex

In the indirect pathway there is less glutamate being released by the thalamus --> decresae movment of unwanted task

Where will the Dopa 1 and Dopa 2 receptors be located

on the striatum

If DOPA synapses at DOPA 1-R, what will be the result?

Movement (the striatum will increase release of GABA

If DOPA synapses on the DOPA 2-R, what will be the result?

Increase movment (the striatum with decrease GABA production) (inhibiting indirect pathway)

What is an example of a HYPOKINETIC DISORDER

Parkinson’s (decrease movement due to lack of dopamine. Can't inhibit D2 so the indirect pathway is working but it can't stimulate D1 so the direct pathways isn’t working)

What is an example of a HYPERKINETIC DISORDER

Huntington’s Disease

Parkinson’s Disease = HYPOKINETIC DISORDER

How does PD affect DOPA 1-R

How does PD affect DOPA 2-R

The dopamine can't stimulate D1 so the direct pathway can't work (decreased movement); the dopamine doesn't stimulate D2 so the indirect pathway does work (increased inhibition unwanted movement)

Huntington’s Disease = HYPERKINETIC; increased unplanned/unwanted movement

What is degenerated in HD

What will be the outcome of HD on the direct pathway (at the Motor Cortex)

What will be the outcome of HD on the indirect pathway (at the Motor Cortex)

Striatum is degenerated = in the direct pathway less glutamate will act on motor cortex so less wanted movement

In the indirect pathway there is more glutamate getting to the motor cortex so an increase in unwanted movement

What is the lobe that is associated with emotional responsiveness, memory formation and emotional connection with memory, with endocrine, visceral, and somatic effectors

limbic lobe

Which gyrus will “house” the hippocampus

parahippocampal gyrus

What is the primary function of the hippocampus

memory and memory consolidation

Which aspect of the limbic lobe is closely associated with emotional memory, preparing the fight or flight reaction, fear, aggression, rage, etc

amygdala

Which structure will act as a neuronal “highway” joining the hippocampus to the mammillary bodies of the hypothalamus

fornix

What structures found in the hypothalamus thus connecting the circuit of papez (memory consolidation) to emotional and endocrine aspects of the limbic system

mammillary bodies

Which aspect of the thalamus will be most associated with the limbic system; memory formation and learning and sends neurons to the cingulate gyrus

anterior thalmic nucleus

Which aspect of the limbic system and circuit of papez will help with emotion to memory; autonomic function regulation, and emotional processing

cingulate gyrusWhat is the outcome of a lesion to the hippocampus (typically and generally, as there is so much more to this than we discuss)

What is the outcome of a lesion to the hippocampus (typically and generally, as there is so much more to this than we discuss)

Not being able to form new memory