Basal Ganglia

cerebral hemisphere

basal ganglia: group of interconnected structures located deep within each _____ _____

grey, unconcious

basal ganglia are _____ matter collections that form a subcortical, _____ motor system

initiation, inhibition, inhibitory, excitatory

basal ganglia general function: ______ and ______ of movement by balancing ______ and ______ impulses

forebrain, diencephalon, brainstem

composed of 4 ____ structures, 1 structure of the ______, and 1 ______ area

motor, emotions, motivation

best known for their role in _____ control, also involved in other cortical functions suhc as _____ and ______

motor cortex, subcortical

mediated by interactions with ____ ____ and ______ structures

motor

_____ circuit: initation of movement

cognitive

____ circuit: connections to prefrontal cortex and cortical association areas

limbic

____ circuit: connections with emotional centers

oculomotor

____ circuit: regulates eye movements

increasing, decreasing

all basal ganglia circuits affect cortical function by either ____ or ____ the activity of cortical neurons

cerebral cortex, striatum, subthalamic

inputs: projections from the _____ _____ to the ____ and ______ nucleus

excitatory

corticostriate inputs make _____ connections

globus pallidus, excitatory, inhibitory

outputs: leave from the ____ ______ and can be _____ or _____

precision

basal ganglia achieve _____ control through a balance between inhibitory or excitatory effects

descending motor pathways, motor, cerebral cortex

the only way basal nuclei can play a role in control of movement is by influencing one or more of the _____ _____ ______, they do this by affecting the activity of the ____ areas of the _____ ____

motor

part of the striatum involved in most ____ functions of the basal nuclei

motor, somatosensory

putamen: receives most inputs from ___ and _____ areas of cortex

premotor, supplementary motor

putamen: projects by way of globus pallidus and thalamus to _____ and ______ areas

caudate nucleus

part of the striatum involved in cognitive functions, reward and reinforcement, and accuracy/speed of movement

association

caudate nucleus: receives most inputs from _____ areas of cortex

prefrontal

caudate nucelus: projects by ways of global pallidus to ______ areas

ventral striatum

part of the striatum that has limbic connections and initiates drive-related behaviors

stereotypic movement

repetitive movements that are hard wired into brain, not consciously learning/not consciously taught but small habits your body picks up

automated movement

movement patterns that were initially mediated/learned by conscious control but have been assumed by the basal ganglia (become automatic)

tone

basal ganglia affects ____ depending on what situation you are in by interacting with motor neurons at the ventral horn of the spinal cord

precision, timed action

neurotransmitters work collaboratively to achieve a balanced inhibition and excitation of movement, which is necessary for _____ and _____ _____

inhibitory

GABA: inhibitory or excitatory?

excitatory

glutamate: inhibitory or excitatory?

both

dopamine: inhibitory or excitatory?

dopamine

ACh changes excitability and is neither inhibitory or excitatory, instead works in opposition of ______

hyperkinetic disorders

disorders characterized by excessive movement and decreased muscle tone

chorea

continuous, rapid, and jerky involuntary movements

axial, proximal, face

chorea often involves ___ and ____ limb areas and movements of the _____

caudate, putamen

chorea often results from a lesion of the ____ and _____

hyperkinetic, caudate, increase

Huntingtons disease is a ______ disorder that involves degeneration of the ____ nucleus and some other areas of the cortex. It causes a ____ in dopamine in the basal ganglia

athetosis

slow, continuous, writhing movements of extremities, movement is aimless/purposeless

agonist, antagonist, striatum

athetosis is caused by continuous/prolonged contraction of ____ and ____ muscle groups and is a result of a lesion to the _____

hemiballismus

violent thrashing of an extremity contralateral to the lesion

subthalmaus, caudate

hemiballismus is often caused by a lesion to the ______ and _____, leading to disinhibition of neuronal activity between thalamus and cortex

stroke

hemiballismus is most often seen in older adults with a ____ affecting that region

hypokinetic disorders

disorders involving impaired intiation of movement, bradykinesia, and increased muscle tone

inhibitory

hypokinetic disorders result from increased _____ output within the basal ganglia

dystonia

hypokinetic disorder characterized by sustained muscle contractions resulting in abnormal postures and repeated movements

tics

disorder of the basal ganglia, repetitive, brief, rapid, involuntary, and purposeless movements involving single or groups of muscles, can also be fragments of movements or thoughts

Tourettes

inherited disorder with childhood onset, likely a BN disorder involving motor and vocal tics

OCD

disorder of the basal ganglia, mental illness in which a person has obsessive thoughts, fears, and worries, develops behavioral compulsions as a result in an attempt to diminish the worry

orbital frontal, cingulate gyrus, caudate nucelus

OCD involves 3 primary brain areas: _____ ____cortex, ______ ____, _____ _____

hypokinetic, dopamine

Parkinsons is a _____ disorder that involves degeneration of _____ producing neurons

initiate, disjointed, uncontrollable

degeneration of dopamine producing neurons leads to decreased levels of dopamine available to the basal ganglia, causing a failure to ____ changes in movement, and movement becomes _____ and _____

rigidity

hypertonicity in all muscles, strength and reflexes remain normal

plastic, lead-pipe, cog-wheel

_____ or _____ rigidity is uniform throught ROM, ______ rigidity is rigidiy interupted by a series of brief relaxations

bradykinesia

slow movements

hypokinesia

few movements

tremor

rythmic movements due to alternating contractions between agonist and antagonist muscles

resting tremor

“pill-rolling”, tend to stop once voluntary movement is intiated and increases with emotional stress

Sinemet, L-DOPA, Carbidopa

most common drug used to treat Parkinsons is _____, which contains ______ and _______

L-DOPA, Carbidopa

______ gets converted to dopamine in the brain, _______ inhibits the breakdown of dopamine

LSVT-BIG

OT specific intervention for Parkinsons that involves high-effort/large amplitude movements while focusing on the sensory awareness of “movement bigness”

deep brain stimulation

stimulating basal nuceli, “pacemaker” for the brain, involves a surgical procedure