Introduction
Motor imagery training is a type of rehabilitation and training technique that’s purpose is to allow individuals to make mental movement patterns without the contraction of any muscles or creating any physical movement with their body (Li et al., 2018). One type of client that this technique could be effective for includes people who have suffered from a stroke, which is a non-communicable disease in which brain damage has occurred due to a disruption of blood being transported to the brain, and in most cases, this is due to a blood clot or burst in a blood vessel (World Health Organisation, n.d.). A stroke has a damaging effect on an affected patient’s ability to perform cognitive, motor, sensory and visual skills (Ren et al., 2019). Because motor imagery training attempts to mentally simulate movement without physically moving the body, this could potentially be an effective method to rehabilitate individuals who have suffered from a stroke. This is important because strokes are one of the major causes of global mortality. According to the Australian Bureau of Statistics (2015), strokes were in the top 3 leading causes of mortality in Australia, responsible for nearly 11,000 deaths in 2015. This paper will review the effectiveness of motor imagery training on stroke patients. This will be examined by presenting evidence about physical movement after a stroke, how a stroke affects the neurophysiology and brain of a patient, motor imagery training, and why motor imagery training would be useful for stroke patients.
Physical movement after a stroke
It is well recognised that a stroke negatively impacts an affected individuals’ ability to move and complete normal daily tasks (Ren et al., 2019). Some of the signs and symptoms associated with a stroke include pain, weakness or drooping to one side of the body or face, slurred speech, vision impairment, and a loss of balance and/or coordination (World Health Organisation, n.d.). Predominantly, these are physical symptoms that have resulted in a loss of sensory in a stroke patient. This is an obvious hurdle for rehabilitation after a stroke, which can delay an affected patient’s movement due to a loss of function in certain parts of the body. This loss of function can lead to movement disorders and further complications (such as paralysis) in the future. According to Starchina (2019), 80% of stroke patients are affected by movement disorders after a stroke has occurred, and this is the leading cause of disability. If stroke patients are disabled due to movement disorders, they may not be able to complete physical activity and even move at all, which could lead to further deterioration of the patient. This decline in health may consequently have a negative impact on their neurophysiology and brain.
How a stroke affects the neurophysiology and the brain of a patient
Although a stroke harmfully affects physical movement of the body, it also has a damaging impact on a patient’s neurophysiology and brain (Quinlan et al., 2015). In other words, when a patient is not able to contract their muscles frequently and create movement with their body/parts of their body, this can also have a negative effect on their brain and neurophysiology. An inability to contract muscles and complete physical activity can result in long term depression of synapses (Murphy & Corbett, 2009). This occurs when the strength of a synapse decreases due to repeated misfiring from a pre synaptic neuron to a post synaptic neuron, not allowing the brain to make these connections and resulting in cell death (Sims & Muyderman, 2010). To prevent this from occurring or to attempt to recover from this, rehabilitation is required. One rehabilitation technique that could provide effective results is motor imagery training.
Motor Imagery Training
As mentioned previously, motor imagery training is a rehabilitation technique that refers to mental simulation of movement without the contraction of any muscles (Li et al., 2018). Mentally rehearsing these movements stimulates regions of the brain that are activated when physical movement is performed (Jeannerod & Decety, 1995). This type of rehabilitation potentially could enhance an individual’s motor learning and could improve their ability to perform locomotor skills (Kumar, Chakrapani, & Kedambadi, 2016). Because of the nature of motor imagery training, it is highly accessible as it is easy to administer, cheap, and a safe method of rehabilitation (Azad, Mahmodi, Arani-Kashani, 2018). It only needs to be educated to individuals so that they can perform this type of rehabilitation training on a regular basis. According to de Vries and Mulder (2007), motor imagery training results in significant alterations in task performance and this is due to a reorganisation at a neural level. Jackson et al. (2003), and Lacourse et al. (2005), suggest that this significant reorganisation was observed in the cerebellum (due to motor imagery training), and had the same effect on the cerebellum as physical training. Although this is the case, would motor imagery training be an effective rehabilitation technique on stroke patients, and if so, how would it assist in the recovery of stroke patients?
Why Motor Imagery Training would be useful for stroke patients
Although stroke patients may not be able to contract their muscles effectively and/or efficiently, they may be able to process these physical movements using their brain through motor imagery training (Ono et al, 2018). This type of rehabilitation training technique could potentially lead to effective recovery and may result in stroke patients being able to physically move again (de Vries & Mulder 2007). Kim et al. (2018), suggests that the supplementary motor area, which is responsible for coordinating complex and bilateral movements, is the most integral region of the brain in regards to motor imagery and advanced motor control because it is reportedly the most active region of the brain during these tasks. Although this is the case, other areas of the brain including the cerebellum, premotor area, primary motor cortex, and posterior parietal cortex are also activated during motor imagery training (Hetu et al., 2013). Performing motor imagery training activates these motor regions of the brain, which can improve neuroplasticity and potentially repair synapse pathways (Emerson et al., 2018). It is also believed that the dorsal pathway, which connects the occipital lobe to the temporal lobe and is responsible for spatial awareness and motion (Kravitz et al., 2013), plays a critical role in regards to the recovery of the upper extremity of the body after a stroke (Lie et al., 2018). In the same study, motor imagery training improved hand function in stroke patients, and it was believed that this type of rehabilitation potentially activated and improved the dorsal pathway of these stroke patients. According to Guerra, Lucchetti and Luchetti (2017), motor imagery training had a positive effect on rehabilitation by improving gait speed, motor performance and balance in stroke patients.
Conclusion
Stroke patients require rehabilitation to give themselves the best chances to effectively recover from any injuries and/or other problems related to their stroke. One of the recommended rehabilitation techniques to treat a stroke would be motor imagery training. This paper has discussed the usefulness of motor imagery training on stroke patients by evaluating the evidence regarding physical movement after a stroke, how a stroke affects the neurophysiology and brain of a patient, motor imagery training, and why motor imagery training would be useful for stroke patients. The evidence supports the use of motor imagery training as a way to rehabilitate patients after they have had a stroke. Stroke patients undertaking this type of rehabilitation could potentially restrict mortality rates, as this type of training could prevent further deterioration post stroke and potentially rehabilitate patients from any damage that has already affected them.
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