Motor control Flashcards
what is the difference between declarative and non-declarative memory?
declarative memory: factual information, life events, easily formed/forgotten, available to consciousness
non-declarative memory: procedural memories = skills and habits, less easily formed/forgotten, not available to consciousness (don’t pull up instructions for how to do them e..g driving)
what is a ballistic movement? give an example
a pre-programmed movement which is rapid at the expense of accuracy eg. swatting a fly away
what is a pursuit/visual feedback movement? give an example
motor command which is continually updated with sensory feedback, highly accurate. eg slow pursuit of a moving car with hand
what is the role fo the prefrontal cortex?
control of movement, decision to make a movement
what area are the supplementary and pre motor area (SMA + PMA) found in ? what is their role?
area 6
involved in planning movements
what areas is the posterior parietal cortex found in?
area 5 and 7
what is the role fo the primary motor cortex? what area is it found in?
area 4
it sends output to muscles to bring about the movement
what areas of the body have the greater representation in the motor homunculus?
face and hands (have fine control)
what is a somatotopic map?
mapping between areas of of motor cortex and muscles of the body
how does the paralysis and loss of sensation caused by stroke relate to the side of the haemorrhage?
paralysis and loss of sensation will be contralateral to side of haemorrhage
of the SMA and PMA, which one receives sensory info from the upper and lower limb?
SMA = upper limb PMA = lower limb
what sensory information is crucial for coordinated movement?
proprioception, vision and balance
what are the main non-cortical brain structures involved in control of movement?
basal ganglia and cerebellum
where do the basal ganglia receive input and output from?
Input from prefrontal cortex (decision about making movement)
Output to pre-motor area/cortex via subthalamic nuclei
what are the functions of the basal ganglia?
Function:
- Initiates movement by putting motor plan into action (PD - difficulty)
- Plans complex voluntary movement
- Important for motor learning (procedural learning related to routine behaviours or habits)
which 2 conditions are caused by disorders of the basal ganglia?
parkinsons’s disease
huntington’s disease
what are symptoms of Huntington’s disease and what causes it?
choreas (random involuntary movements), difficulty speaking and swallowing, progressing to general cognitive decline
Inherited - triplet repeat disease
where does the cerebellum receive input and output from?
Input: mainly from sensory cortex
Output to primary motor cortex via subthalamic nuclei
What are the functions of the cerebellum?
- Coordination and smooth execution of movements
- Motor learning, error detection
what does damage to the cerebellum cause?
cerebellar ataxia - poor coordination
what are skeletal muscle fibres innervated by?
alpha-motor neurons
what is a motor unit?
a functional unit formed by a motor neuron and the muscle fibres it innervates
what are collections of motoneurones in the ventral horn also known as?
motonuclei
what different body parts do cervical, thoracic and lumbar and sacral motor neurones control?
cervical = arms and upper body
thoracic = trunk
lumbar and sacral = legs
how can strength of a muscle contraction be graded?
by recruitment of motor neurons
