CH 3 Flashcards
(26 cards)
Supplementary motor complex
Transmits information to other brain regions who are then responsible for innervating the specific muscles required to execute those movements.
Parietal lobe
Orientation of space
Neuromuscular junction
Synapse between neuron and muscle fibre, It is larger and more specialized than a typical synapse.
Motor tracts
Allow messages to be carried to the muscles from the cortical and subcortical regions of the motor cortex.
Lateral motor pathways
Responsible for the fine movements of distal limb muscles (eg: foot, arm). This tract is contralateral, thus damage to one side affects the other side’s movements. Damage to the lateral corticospinal tract has profound effects on the ability to reach, grasp and manipulate objects.
Medial motor pathways
More involved with movement of trunk and the proximal limb muscles. Projects contralateral and ipsilateral, Involved in posture, standing, bending etc.
Non-cortical regions affect the manner of movement whereas cortical regions code for type and sequence of movement.
Cerebellum
Coordinates muscle movement timing, planning and learning of motor skills.
Vestibulocerebellum
Damage here leads to posture and balance difficulty
Spinocerebellum
Located in medial regions of cerebellar hemisphere, receives somatosensory and kinesthetic information from spinal cord Damage results in difficulty of smooth muscle control.
Cerebrocerebellum
Receives input from different regions of the brain, involved in regulation of highly skilled movement that requires complex spatial and temporal sequences involving sensorimotor learning.
Cerebellar ataxia
Staggered jerky and zigzag motion. Combination of dysmetria (Over/undershooting of movement endpoints) and action tremor.
Dysarthria
Monotonous, slurred speech.
Forward model
Predicting the muscle movement needed ahead of time by using past information.
Ballistic movement
Rapid movement with velocity with no adjustments made once the action is being taken
Basal ganglia
Caudate nucleus, putamen and nucleus accumbens (together known as striatum), the globus pallidum, substantia nigra and subthalamic nucleus.
synchronized cortical activity. Forms loops around each cortical region. Receives input from caudate and putamen.
Basal ganglia theory: Chunks certain actions together individually to coordinate, stereotype and habitual units of action.
Basal ganglia theory 2: Aids ability to execute movement with varying vigor
Basal ganglia direct pathway [Excitation]
cortex -> striatum -> globus pallidus -> thalamus
Basal ganglia indirect pathway [Inhibition]
Cortex -> striatum -> globus pallidus (outer) -> subthalamic nucleus -> globus pallidus (inner) -> thalamus
Parkinson’s disease
Result from damage in substantia nigra, stops dopamine production. Includes tremors, bradykinesia, akinesia, cogwheel rigidity (can only push so far before resistance)
L-dopa
A metabolic precursor to dopamine which can be given to Parkinson’s patients.
Deep brain stimulation
Electrodes are chronically implanted in the brain, stimulating subthalamic nuclei
Huntington’s disease
Abnormal movement, cognitive deficits. Caused by autosomal dominant genes.
Tourette’s Syndrome
Repetitive involuntary vocal and motor actions
Premotor ventral area: Contains mirror neurons which fire even when someone else is doing a task as if you were the one doing it
Cingulate cortex
Aids in control and planning of movement under certain conditions
Apraxia
Inability to perform skilled, sequential, purposeful movement that cannot be for by disruptions in more basic motor processes.
