control of movement Flashcards
proprioception=
- Proprioception is the body’s 6th sense, its awareness of the body in space. It’s the body’s ability to sense self-movement, position and its body position.
- Proprioceptive info is sent via dorsal column and spinocerebellar pathways.
- Proprioceptors involved are muscle spindles and Golgi tendon organs.
Targets of proprioceptive information
Somatosensory cortex
Primary motor cortex
Pre-motor cortex
Basal ganglia
Cerebellum
Brain stem nuclei
Spinal cord
Proprioceptive deafferentation=
loss or impairment of proprioceptive input from body to the CNS, due to damage of proprioceptors or pathways.
What is the vestibular system?
- The vestibular apparatus/ system senses movement of head and acceleration. It is in the inner ear.
Accelerometer=
records motion, movements and accelerator, examples within the inner ear that represent these accelerometers are semi-circular canals, utricle and saccule otoliths.
What are ampullae?
Found in the semi-circular canals, they sense rotational movement of the head.
What does the brain stem have a series of?
vestibular nuclei
What are the 4 outputs/ targets of vestibular nuclei?
- Oculomotor cortex
- lower motor neurons
- cervical spinal cord
- cerebellum
what is the dorsal visual stream?
located in parietal lobe or cerebral cortex. Extends to occipital lobe to sensory associative areas
What is the ventral visual stream?
located in temporal lobe or cerebral cortex and extends to insula and temporal lobe memory areas.
Predict the likely functional consequences for control of movement associated with impairments of the visual or vestibular systems
- Dizziness/ vertigo
- Balance disorders
- Lack of coordination
- Bouncing vision
Basal ganglia=
group of subcortical nuclei responsible for motor control
Identify the structures of the brain that comprise the basal ganglia
- Caudate nucleus
- Putamen
- Globus and pallidus
- Subthalamic nucleus
Substantia nigra=
in the middle of the brain, produces dopamine allowing to facilitate direct/ indirect pathways
What is Parkinson’s disease?
a neurodegenerative disorder characterized by progressive loss of dopamine in the substantia nigra.
what are the motor symptoms of Parkinson’s disease?
Bradykinesia (slowness of movement) tremors, rigidity all related to disruption to basal ganglia circuits in the substantia nigra.
What is the cerebellum?
- Cerebellum is 50% neurons so is important. It controls what happens in motor cortex.
What are the functional divisions of the cerebellum?
Vestibulocerebellum, corticocerebellum and spinocerebellum.
Briefly describe the clinical features of lesions associated with the cerebellum.
- Ataxia
- Asynergia
- Dysmetria
- Scanning speech
- Decomposition of movement
