Motor control Flashcards
What are reflex movements?
Rapid reproducible, automatic motor responses to external stimulus
Involves peripheral nerves and spinal cord
Involuntary
What are voluntary movements?
Wide variety of movements of varying speed, duration and complexity
Typically involves couples patterns of sensory and motor processing
What is a stretch reflex?
Monosynaptic reflex
Receptor is stimulated which activates a sensory neuron, the information is processed in CNS, motor neuron activation and peripheral effector responds
What happens when stretch receptors lengthen?
Mechanically gated ion channels open causing depolarisation
What is a withdrawal reflex?
A non voluntary polysynaptic reflex
Receptor stimulated -> sensory neuron activated -> info processed in CNS -> motor neuron activated -> peripheral effector responds
How is the cerebral cortex involved in performing movements?
Plans and initiates voluntary motor activity
How is are the thalamus and midbrain involved in performing movements?
Control reflexes in response to visual and auditory stimuli
How is the cerebellum involved in performing movements?
Coordinates complex motor patterns through feedback loops
How are the brain stem and spinal cord involved in performing movements?
Control simple cranial and spinal reflexes
How are the pons and medulla oblongata involved in performing movements?
Control balance reflexes and more complex respiratory reflexes
How is the hypothalamus involved in performing movements?
Controls reflex motor patterns related to eating, drinking and sexual activity : modifies respiratory reflexes
How is the basal nuclei involved in performing movements?
Modifies voluntary and reflexive motor patterns at the subconscious level
What does the prefrontal cortex do?
Organises thoughts and actions. Intimately involved in ‘executive functions’ i.e. cognitive function and social behaviour
Order in brain for planning a movement
Decision in frontal lobe -> pre motor cortex -> basal nuclei and cerebellum
What is involved in performing a movement in the brain?
The basal nuclei adjust patterns of movement and cerebellum monitors balance and equilibrium
