motor control and action selection Flashcards
what are two things motor control and action selection are capable of
very complex sequences of actions
performing multiple behaviours simultaneously
what did stimulation studies identify
topographic map of organisation of primary motor cortex
what are two brain regions which control movement
primary motor cortex and cerebellum
describe cerebellums relationship with movement
acts in conjunction with primary motor cortex and computes contributions of muscles to perform movements
what is the projection course of the cerebellum in movements
via the ventrolateral thalamus back to motor cortex which allows current movement modification
what are three effects of damage to different areas of cerebellum
flocculondular or vermis damage= postural and balance problems
intermediate zone damage- limb rigidity
lateral zone damage- weakness and decomposition of movement
what causes ataxic gait
damage to cerebellum
how do we plan and execute sequences of movements
premotor cortex and supplementary motor area (SMA) for motor planning
what is the SMA critical for
learned sequences - lesions impair these and neurons respond to specific parts of a learned sequence
what does inactivation of SMA lead to
doesnt disrupt single movements but impairs the abilityt to make a sequence of movements
what does stimulation of SMA lead to
involuntary movements
how are actions encoded in the brain
mirror neurons
what are mirror neurons and where are they found
neurons in ventral premotor cortex and inferior temporal lobe that respond to a particular movement or the sight of someone else perfoming it
when are mirror neurons most active
for well practised behaviours
what are the 2 functions of mirror neurons
imitation and mechanism for understanding the actions of others
what do mirror neurons encode
intention rather than just action- subjects shown clips of context for drinking tea ventral premotor cortex shows greater activation when intention is cleat
describe the relationship between mirror neurons and autism
less active and so lack of activity could lead to autism
what are three examples of the cause of movement disorders
cerebellar damage
neurodegenerative disorders
damage to cortical motor areas- apraxia
what is limb apraxia
inappropriate limb movement especially to verbal commands
what causes limb apraxia
damage to left frontal/ parietal cortex
what is constructional apraxia
inability to perceive and imagine geometric relations
caused by damage to the right parietal cortex
what is hemorrhagic stroke
burst blood vessel
what is an obstruvtive stroke
blood vessel blocked
what is a glioma tumour
malignant
what is a meningioma tumour
benign
