Control of Movement Flashcards
All voluntary movement is a result of the contraction/relaxation of ______ or striate muscle. These muscles contain ______ bridges which pulls two proteins apart called ______ and _______.
Motor neurons ______ in the muscle grooves. They release ACh into the NMJ (kind of like a synapse but not really as it’s in the muscle). ACh binds to ______ receptors on the motor _______. This triggers the release of Ca ions to cause muscle _______.
The precision of movement is determined by the number of ______ innervated by each motor _____.
skeletal
cross
actin
myosin
terminate
nicotinic
endplate
contraction
fibres
axon
Voluntary control of muscles is a result of _______ inputs from the brain. All motor signals go to muscles via the ______ _____ or _____, which serve as a relay centre.
However, these areas are also involved in motor-control for _____ responses or adjustments (eg: ______), and _______ movements such as breathing and walking. These are driven by ______ ______ generators.
The brain is responsible for _______ motor programs (eg: begin walking) and ______ actions (eg: changing direction)
(aka, SC and BS do have some independence, but predominantly signals come from the brain)
descending
spinal cord
medulla
fast
reflexes
ongoing
central pattern
initating
altering
Brain OUTPUT areas (1)
What aspects of motor control is the MOTOR CORTEX responsible for?
- control of muscles in arms, hands and finger
- voluntary manual movements (eg: writing, picking up an object, etc)
–> this is the most evolved in humans - fine movements (eg: playing an instrument and typing
Brain OUTPUT areas (2)
What aspects of motor control is the RED NUCLEUS responsible for?
- controls arms and legs
- limb movements INDEPENDENT of the trunk (eg: reaching while remaining stationary)
Brain OUTPUT areas (3)
What aspects of motor control is the BRAINSTEM responsible for?
- controls muscles of the trunk, neck and proximal limbs (upper arms/legs)
- posture, correcting balance
MOTOR CORTEX
The motor cortex sends connections to the spinal cord, ____ nucleus, thalamus, _____ ganglia etc. These connections from the cortex to the subcortical structures go via the _____ ______.
If you have a stroke here it can cause _______ which prevents cortex from sending signals to the brainstem. There is a loss of _______ movement.
Another example - man could smile when there’s an emotional response (controlled by BS) but could not “bare his teeth” when asked as this is a voluntary movement. Shows distinction between motor cortex and subcortical areas.
red
internal capsule
basal
hemiparesis
voluntary
MOTOR CORTEX
What are the 3 areas of the motor cortex and what do each of them contain?
- Primary motor cortex (M1)
- Supplementary motor area (SMA)
- Pre-motor area (PMA)
Each contain their own, different, independent, map of the body (for each half of the body)
MOTOR CORTEX
The primary motor cortex (M1) has a large amount of it’s map dedicated to…
Hence, it is involved in…
it’s output to spinal cord is via…
…hands, lips, tongue
…fine execution of movement
…corticospinal (pyramidal) tracts and red nucleus
MOTOR CORTEX
The pre-motor cortex and supplementary motor area (SMA) is involved in…
This is seen in experiments where….
It’s map of the body…
…planning of movements
..neurons become active in anticipation - when waiting for a “go” signal we see activity build up OR when imagining a movement. The movement can be aborted.
…is much courser
MOTOR CORTEX
- Coding of Movement
Neurons in the SMA and PMA code for ______ direction or _________ of movement.
This was seen in an experiment where monkeys hold a joystick. They are told which _______ to move it but have to wait for a ______. Certain neurons light up which now are known to code for _______.
BUT interestingly, neurons in these areas are active during the ______ period, demonstrating the role of the SMA and PMA in anticipating movement and _______.
Another example of this is in the monkey clock experiment where they had to move the joystick ____ degrees to the light and the ______ of neurons could be tracked during the ______ process.
anticipated
destination
direction
signal
direction
delay
planning
90
spread
thought
Cerebellum Inputs and Outputs
Each of the cerebellums controls the ______ half of the body. It contains ____% of all the brain’s neurons (hence, very ______ packed).
The cerebellum receives ______ inputs (eg: vestibular, somatosensory, proprioception, visual, auditory) AS WELL AS inputs from the _______.
It sends outputs to the ___ _______ and to the ______. It has no connections with the _____ _____.
Hence, it is not involved in the _____ control of movement, but rather _______ and fine-tunes movement
opposite
50
densely
sensory
cortex
red nucleus
cortex
spinal cord
direct
influences
Cerebellum and Movement
Describe the two main movement functions of the cerebellum
- Important for smooth execution of coordinated movement sequences (including speech)
- -> damage results in jerky, uncoordinated movements - Important in learning complex skills and precise movements (including playing an instrument, riding a bike, etc)
Especially movements that rely on a lot of sensory information to control the movement.
It is very adaptive (eg: wearing mirror goggles)
Cerebellum and Cognition
The cerebellum has connections with the pre-frontal cortex, hence damage here could result in deficits in executive functions. Describe the three experiments discussed in the lecture which highlights the cerebellum as being involved in this.
- Generate a verb appropriate for the noun as opposed to reading it. They found the right cerebellum more active with the task requiring more cognitive processing. Must be involved in semantic processing somehow.
- Attending to semantic meaning of a word as opposed to superficial word tasks (eg: rhyming)
- Lying vs truth telling when answering questions related to a story - lying resulted in left cerebellum activation
