Neaural Control Of Action And Disorders Of Motor Fucntion Flashcards
Motor system
Part of the nervous system implicated in all movement
What is the role of the prefrontal cortex
Plans movements
What is the role of the premotor cortex?
Organises movement sequences
What is the role of motor cortex?
Produces specific movements
What is the role of posterior cortex?
Provides sensory information
Midline lesions in the homunulous affect what?
- balance
- posture
- walking
- eye movements
Lateral lesions in the homunculus affect what?
- arms
- hands
- fingers
What is the role of the basil ganglia
Regulates activity in motor and pre-motor cortex
Release of inhibition allows motor system to produce action
What is hyperkinetic disorder?
Involuntary/ exaggerated movements e.g. Tourette’s disorder
What is a hypokinetic disorder?
Muscle rigidity/ difficulty invitations movements e.g. Parkinson’s disease
Excitatory activity to Gpi
- inhibits activity to thalamus
- lower input to cortex
- reduces force
Inhibitory activity to Gpi
- Thalamic activity less inhibited
- Higher input to cortex
- increase in force
Lateral premotor cortex
- Input from parietal lobes
- monitoring state of environment
- role in interacting with external objects
Medial premotor cortex
SMA: supplementary motor area
- strong proprioceptive connections
- associated with well-learned actions
What are the symptoms of ataxia?
- loss of controlled and coordinated muscle movements.
- irregulatrity of muscle action
What ares of the brain is associated with ataxia?
Cerebellum
What are the symptoms of apraxia?
- inability to make or copy purposeful movements despite proper coordination and adequate muscle power
What area of the brain is associated with apraxia?
Cerebral cortex
What are the three types of apraxia?
- ideometer apraxia
- constructional apraxia
-apraxia of speech
What is ideometer apraxia?
Inability to plan or complete voluntary actions
What is an example of something that someone cannot do with ideometer apraxia?
- tying their shoes
What is constructional apraxia?
Disorder of spatial organisation
What activity would someone with constructional apraxia find challenging?
- completing a jigsaw
- drawing a picture
What part of the brain is damaged in ideometer apraxia?
Left posterior parietal Cortex
What part of the brain is damaged in constructional apraxia?
Either posterior parietal lobes
