Neuroplasticity in rehabilitation

Taken from Wikimedia Commons

A few weeks ago I attended a short presentation by Professor Meena Iyer from Missouri University. Her lecture was on the role of neuroplasticity in occupational therapy rehabilitation, although the principles of her talk apply across all of the allied health sciences. Here are the notes I took:

Plasticity: brain structure and function can be influenced throughout life by experiences i.e. it is flexible, and it has a clear age-dependant determinant, includes several morphological changes and many types of brain cells

 

 

 

Occurs under 2 primary conditions:

  • Normal brain development within normal individuals: performance shapes plasticity
  • As as adaptive mechanism to compensate for lost function and/or to maximise remaining functions in the event of brain injury

The environment and actions of an individual play a key role in influencing plasticity, but not as a result of desire

Is plasticity related to functional outcome?

Example of plasticity: the visual cortex is involved in the sense of touch in people who are blind (even if only blinded for a few days) i.e. the cells in the visual cortex take over the responsibility for “seeing” what the fingers feel. In addition, disrupting the visual cortex (with magnetic stimulation) has a negative impact on people’s ability to read braille. See PBS video – Changing your mind (2000). Scientific American Frontiers (www.pbs.org)

When areas of the brain are not stimulated (e.g. when the visual cortex isn’t stimulated in people who are blinded), those areas very soon take over other functions that were not necessarily related to their original function i.e. dormant pathways are activated

“It appears that in the blind, brains areas commonly associated with the processing of visual information are not rendered “silent” by visual deprivation but rather are recruited in a compensatory cross-modal manner” – Theoret, Merabet, Pascual-Leone (2004). J Physi Paris, 221

There are changes in:

  • Dendritic morphology
  • cortical maps
  • Synaptic strength
  • Neurogenesis
  • Axonal trajectory
  • Synpatic morphology
  • Synaptogenesis
  • Gene expression

The brain adapts in response to injury

When a nerve is injured, the areas of the brain responsible for movement and sensation of the injured part starts to change i.e. cortical reorganisation

Constraint induced therapy: impair the unaffected side so that the patient must use the affected side for function (accepted rehabilitation method, although original work had no control group, and no controlled study has been done since)

Promoting plasticity – principles of treatment

  • Use it or lose it
  • Use it and improve it
  • Plasticity is experience specific
  • Repetition matters (corollary: changes may not appear in the early stages of rehabilitation)
  • Intensity (time) matters: continuous training over long periods is needed to change the neural substrate of behaviour
  • Time matters: different forms of plasticity may occur at different times in recovery after an injury → plasticity may involve a sequence of phenomena
  • Salience matters: activity should be meaningful to the person
  • Age matters (change occurs more readily in younger people, so it’s important to build up “cognitive reserve’)
  • Transference is possible: training in one area may enhance behaviour in related areas
  • Interference can occur: some changes in plasticity may disrupt or limit certain behaviours or skills

 

Posted to Diigo 12/10/2010

    • The zone of proximal development is the area between what an individual can achieve on their own and what they can achieve with assistance
    • A student should constantly be reaching slightly beyond their capabilities rather than working within them
    • students should lead their learning and teachers simply assist and rather than judging students on what they know in standardised tests, learning should be done through looking closely at their zone of proximal development
    • If informal learning is as important as formal learning, then varying the way students are assessed can only work in their favour
    • Relevant, meaningful activities that both engage students emotionally and connect with what they already know are what help build neural connections and long-term memory storage
    • it’s necessary for learners to attach a new piece of information to an old one
    • If a student acquires new information that’s unrelated to anything already stored in his brain, it’s tough for the new information to get into those networks because it has no scaffolding to cling to
    • a solid amount of research also links personal relevance and emotional engagement to memory storage
    • “the learner’s emotional reaction to the outcome of his efforts … shapes his future behavior,”
    • if [a student] doesn’t believe a particular activity is interesting, relevant, or within the scope of his capabilities, it’s probably not going to sink in
    • too much emotion can be as detrimental to learning as too little: distractions and stress can also block receptivity to new ideas
    • Make it student directed. Give students a choice of assignments on a particular topic, or ask them to design one of their own. “When students are involved in designing the lesson, they better understand the goal…and become more emotionally invested in and attached to the learning outcomes.”
    • Connect it to their lives and what they already know. Taking the time to brainstorm about what students already know and would like to learn about a topic helps them to create goals — and helps teachers see the best points of departure for new ideas. Making cross-curricular connections also helps solidify those neural loops
    • With no reference point and no intrigue, information is fairly likely to go in one ear and straight out the other
    • Happy learners are healthy learners, if students do not feel comfortable in a classroom setting, they will not learn. Physiologically speaking, stressed brains are not able to form the necessary neural connections
    • The amygdala, for instance, processes emotions, stores the memories of emotional reactions, and reacts so aggressively to stress that it will physically prevent information from reaching the centers of the brain necessary for absorbing new knowledge
    • Even feelings like embarrassment, boredom, or frustration — not only fear — can spur the brain to enter the proverbial “fight or flight” mode
    • The amygdala goes into overdrive and gets in the way of the parts of the brain that can store memories
    • it makes sense — on many levels — to cultivate the learning atmosphere as much as the learning itself. “Reducing stress and establishing a positive emotional climate in the classroom is arguably the most essential component of teaching,”
    • Make the classroom stress free. Lighten the mood by making jokes and spurring curiosity; create a welcoming and consistent environment; give students frequent opportunities to ask questions and engage in discussions without judgment; and determine achievable challenges for each learner
    • Encourage participation, not perfection. A classroom in which mistakes are encouraged is a positive learning environment, both neurologically and socially speaking
    • “Students will allow themselves to experience failure only if they can do so within an atmosphere of trust and respect.”
    • This kind of positive reinforcement from the get-go allows students to let their guard down (known in neuro-speak as calming their “affective filters”). Listening to students in general, and listening to their intentions in particular, can help relax anxious brains.
    • Practice active listening. “Focus on what students are trying to say
    • Intelligence is not fixed, it turns out, nor planted firmly in our brains from birth. Rather, it’s forming and developing throughout our lives
    • neuroplasticity is defined as the selective organizing of connections between neurons in our brains
    • neuroplasticity is defined as the selective organizing of connections between neurons in our brain
    • “cells that fire together, wire together”
    • “Practice makes permanent. The more times the network is stimulated, the stronger and more efficient it becomes.”
    • both morale and grade points increase when students understand the idea that intelligence is malleable
    • Practice, practice, practice. Repeating an activity, retrieving a memory, and reviewing material in a variety of ways helps build thicker, stronger, more hard-wired connections in the brain
    • Put information in context. Recognizing that learning is, essentially, the formation of new or stronger neural connections, it makes sense to prioritize activities that help students tap into already-existing pathways
    • “Whenever new material is presented in such a way that students see relationships between concepts, they generate greater brain cell activity and achieve more successful long-term memory storage and retrieval.”
    • Let students know that this is how the brain works. “Especially for students who believe they are ‘not smart,’ the realization that they can literally change their brains through study and review is empowering.”