motor control and learning Flashcards
what is motor control?
- systematic regulation of movement in organisms with a nervous system
what processes does motor control include?
- includes processes that govern the initiation, direction, amplitude and velocity of voluntary and involuntary movements
what is motor control described as?
- described as integrating sensory information (visual, vestibular, and somatosensory inputs) and motor responses
what is the motor control process critical in?
- critical in performing simple to complex movements
what people are motor control processes impaired in? - give an example
- impacted in individuals with neurological impairments
e.g., those recovering from stroke
what is motor learning a set of?
- set of internal processes associated with practice or experience
what does motor learning lead to?
- leads to relatively permanent changes in the capacity to produce motor skills
what is the process of motor learning describe as? what does it involve?
- complex process
- involves acquiring or modifying the ability to perform a skill
how is motor learning achieved?
- achieve through repeated practice and sensory feedback
when is motor learning crucial?
- crucial in rehabilitation as it underpins the reacquisition or improvement of motor skills following injury/ disease
what do motor control theories explain?
- explain how the nervous system provides coordinate movement
why are specific motor control theories particularly relevant in physiotherapy and neurological rehabilitation?
- as they provide a framework for understanding and treating movement disorders, especially in patients with neurological impairments
what does the applicability of motor control theories lie in?
- lie in their ability to explain the mechanisms underlying motor control & to guide development of effective therapeutic intervention
what are the 5 main motor control theories?
- motor programme theories
- systems theory
- dynamic systems theory
- ecological theory
- neurofacillitation approaches
what are motor programme theories important in?
- important in understanding how movement patterns are learned, stored & retrieved
who are motor programme theories especially important to?
- especially important in rehabilitating patients who need to relearn motor skills following neurological events e.g., TMI, stoke
how are motor programs retrained?
- retrained by therapeutic interventions
- through repetitive practice and skill acquisition
what does the systems theory emphasis?
- emphasises the role of various bodily systems and their interactions in movement control
what does systems theory support?
- supports a holistic approach to treatment, where therapists consider the neuromuscular system and interaction with other systems like skeletal and sensory
what does the systems theory guide?
- guides therapist in designing interventions that consider the whole body and the patient’s environment
what are dynamic systems theory relevant for?
- relevant for understanding how patients adapt to changes in their bodies and environments following neurological injury
what does the dynamic systems theory suggest?
- suggests that therapy should focus on facilitating the emergence of new, functional motor patterns by manipulating task and environmental constraints
what does the dynamic system theory benefit?
- benefits stroke rehab
- where patients often develop new movement strategies to compensate for lost function
what does the ecological theory underscore?
- underscores the importance of the environment in shaping motor behaviour
what does the therapy based on ecological theory involve ?
- involves creating an environment that encourages patients to adapt their movements in real- world situations
what does the ecological theory support?
- supports task- oriented approaches where patients practice functional tasks in various settings to enhance their adaptability & independence
what does the neurofacilitation approach involve?
- involves approaches like Bobath (Neuro- Developmental Treatment), Proprioceptive Neuromuscular Facilitation and the Rood Approach
what does neurofacilitation approaches focus on?
- focus on facilitating normal movement patterns through specific handling techniques an sensory stimulations, particularly useful in the early stages of neurological rehab
what happens in stroke and what does this affect?
- loss of blood supply to one part of the brain
- affects one side
what happens to nerve cells after stroke?
- nerve cells starved of oxygen so they die and stop functioning
what happens when nerve cells die? what response is caused?
- once nerve cells have died, they cannot be re-generated so impairments form
- inflammatory responses causes swelling which affects more nerve cells
what is the area called that surrounds an ischemic event?
- penumbra
what are the four post- lesional physiological changes?
- oedema
- diaschisis
- excitotoxicity
- apoptosis
what is oedema?
- fluid accumulation in tissues
- function impaired but only temporarily
why do you need to take action with oedema?
- need to take action to ensure that the extended area doesn’t become permanently damaged as it is resolvable
what is diaschisis?
- sudden change of function in a proportion of the brain connected to a distant, but damaged brain area
where are nerve cells lost in diaschisis?
- lose nerve cells far away from the directly affected area (wide spread)
what is excitotoxicity? what is released?
- secondary process where the nerve cells suffer damage or death due to high neurotransmitters
- neurotransmitters are released
what does the NT release in excitotoxicity cause?
- causes the surrounding nerve cells to be overwhelmed
- overwhelmed cells axonal membrane damage, which causes breakdown
what is apoptosis?
- programmed cell death of useless nerve cells (area size is affected after primary problem is increased)
what happens as oedema resolves?
- spontaneous recovery occurs
- nerve cell function is re-established
what happens after post- lesional physiological changes?
- fewer connections
- decreased ability to function
what is the point of injury induced plasticity?
- after leisons, brain tries to re-establish connections
what are the 5 mechanisms for injury induced plasticity?
- denervation hypersensitivity
- synaptic hyper effectivness
- unmasking silent synapses
- regenerative synaptogenesis
- reactive synaptogenesis
what is denervation hypersensitivity?
- increase of sensitivity of postsynaptic membranes
- makes it easier to depolarise and generate action potentials in nerves that have lost some of their inputs
what is synaptic hyper effectiveness?
- synapse becomes stronger to make up for lost function
- takes smaller amounts of neurotransmitters to generate action potentials
what is regenerative synaptogenesis?
- involves attempting to re-establish the synapse that they lost with other nerves
what is reactive synaptogenesis?
- collateral spouting> sprouting out from undamaged axon onto neurons nearby to try and maximise the connections
what is the cortical activity after a stroke within first couple of days? (3)
- fewer connections
- fewer activity
- decreased neural activity in certain parts of the brain
what happens in cortical activity over 5-10 days after stroke?
- area grows via making new connections
- normally scattered
what is the cortical activity 4 months post stroke?
- stroke patient at the equivalent area of the healthy subject
- gets rid of not necessary connection and keep the relevant connections
what are the 10 principles of use- dependent plasticity?
- use it or lose it
- use it and improve it
- specificity
- repetition matters
- intensity matters
- time matters
- salience matters
- age matters
- transference
- interference
what does development of function require?
- requires task specific practice with lots of repetition at high intensity to ensure that the patient uses it
is use- dependent plasticity an easy process? can you go back to normal level?
- hard process
- changes are possible but not possible for every aspect of movement
what is the challenge of motor learning for individuals with cognitive impairment? - who would this affect?
- individuals after MS/ stroke
- may prevent use of explicit learning mechanisms such as feedback use, ability to perceive the environment, etc
what is a challenge of motor learning for an individual with Parkinson’s Disease?
- process of automatization is harder as Basal Ganglia affected by PD so more thought and concentration required
when is ability to fine tune and co-ordinate movement impaired in motor learning?
- impaired due to cerebellar impairment, which may prevent use of sensorimotor adaptation
how do we become more skilled at movement tasks?
- can become more skilled by finding a different way to complete a skill that we were previously able to o
what is skill acquisition?
- ability to reliably deliver accurate execution
what do you need to understand for skill acquisition?
- understand the task and attempt to complete the task consistently to get the outcome that we want
where does the skill acquisition process take place?
- takes place within CNS with some changes in the PNS
what is the trade off in skill acquisition?
- speed and accuracy trade off
- can change as we learn to see differences
how long does skill acquisition take?
- it is a slow process
- change takes a long period of time
what is skill acquisition driven by?
- driven by cellular changes
- neuroplasticity
what does individual cellular changes between communicating nerves lead to?
- leads to system level changes to move activity from one part of CNS to another
what is an example of individual cellular change to system level change?
- movement transferred from cortical areas (conscious movement) to sub- cortical areas (automatic, less cognitive effort to complete the movement)
what are the three system level changes?
- move from cortical to sub- cortical
- automatization
- decreased cognitive effort
what are the four distinct features of motor learning mechanisms?
- instructive
- reinforcement
- use- dependent
- sensorimotor adaptation
what does instructive learning involve?
- told how to move and able to move in the way suggested
what is instructive learning based on? what is the primary driver?
- strategy based
- primary driver is performance- based external feedback
what is the primary neural substrate involved in instructive features? how much cognitive load is required?
- prefrontal cortex (cortical layer of the brain where the gray matter sits)
- requires a high level of cognitive load
what is reinforcement?
- feedback that allows you to pick the right type of combination of movements to obtain desirable outcome
- does the thing I want to happen, happen as a result of the movement?
what is the primary driver of reinforcement?
- outcome- based external feedback
what is the primary neural substrate involved in reinforcement? what is the cognitive load?
- occurs in basal ganglia, which initiates the combination of movements
- high cognitive load
what is the use dependent feature?
- focuses on repetition to strengthen the connection of nerves that make the correct form of movement occurs
how is consistent successful movements ensured?
- connections hardwire
what is the primary neural substrate involved in use- dependent feature? what is the cognitive load?
- occurs in the motor cortex and spinal cord
- low cognitive load
what is sensorimotor adaptation?
- can predict what may go wrong with a movement via experience
what is the primary neural substrate involved in sensorimotor adaptation? what is the cognitive load?
- occurs in the cerebellum
- low cognitive load
what does long term potentiation do?
- strengthens connections between nerves
what receptors does long term potentiation involve?
- voltage gated NMDA receptors in the membrane at a new synapse site
when is there a Ca2+ influx?
- when there is a coactivation of pre and post- synaptic membranes
what does Ca2+ influx stimulate?
- stimulates insertion of non- voltage gated AMPA receptors into membranes
what happens due to the resultant increase from long term potentiation?
- resultant increase in post- synaptic response to glutamate release from pre- synaptic neuron
what does long term depression involve?
- connection not being used is moved out of the membrane
what are the two main steps of long term depression?
- decreased post- synaptic Ca2+ results in reduction of AMPA receptors initially
- followed by deletion of synapses if continued failure to coactive
is long term depression long lasting?
- not a permanent process as can regrow synapses
- irrespective of where its occurring in the brain
what are forms of plasticity dependent on?
- dependent on times during training e.g., first learning vs refinement
