Role of Rehabilitation in Neural Plasticity

AIM: Verifying if physical therapy, neurostimulation techniques, aerobic fitness and video games can induce neural plasticity making it possible for cortical reorganisation, motor recovery in patients, improvement of cognitive functions and transfer of spatial knowledge in the everyday living environment. METHODS: There have been revised scientific articles respectively focused on the role of pain, the role of physical therapy, neurostimulation techniques and video games in cortical reorganisation. Articles related to the role of pain have taken in the study subjects with pain, to observe its role in cortical reorganisation. Studies related to physical therapy and neurostimulation techniques after cerebrovascular accident consisted of the involvement of these subjects which exposed to different neurostimulations. Also, related to cognition and video games subjects exposed to these interventions for cognitive benefits. RESULTS: From all articles reviewed there have been effective results of neurostimulation techniques, aerobic fitness and video games in cortical reorganisation inducing neural plasticity (p < 0.05) toward motor recovery, improvement of executive functions and transfer of spatial knowledge. CONCLUSION: Rehabilitation through locomotor training and neurostimulation techniques, improves mobility in subjects after a cerebrovascular accident due to cortical reorganisation. Also, through aerobic fitness and video games, there have been improvements in cognitive functions. This way, rehabilitation dedicated to the promotion of well-being and health urges beneficial neuroplastic changes in brain corresponding in functional improvement.

Effect of one session of mirror therapy on phantom limb pain and recognition of limb laterality in military traumatic lower limb amputees: a pilot study

Up to 70 % of military amputees suffer phantom limb pain (PLP), which is difficult to treat. PLP has been attributed to cortical reorganisation and associated with impaired laterality. Repeated sessions of mirror therapy (MT) can benefit PLP; however, anecdotal evidence suggests one MT session could be effective. In a one-group pretest and post-test design, 16 UK military unilateral lower limb amputees (median age: 31.0, 95% CI 25.0 to 36.8 years) undertook one 10 min MT session. Visual analogue scale (VAS) pain and laterality (accuracy and reaction time) measurements were taken pre-MT and post-MT. Median VAS PLP did not differ significantly between pre-MT 15 mm (2–53 mm) and post-MT 12 mm (1–31) (p=0.875) scores. For the amputated limb, there were no significant differences between pre-MT and post-MT scores for laterality accuracy, 95.3%, 95% CI 90.5% to 97.6% and 96.7%, 95% CI 90.0% to 99.4%, respectively (p=0.778), or reaction time, 1.42 s, 95% CI 1.11 to 2.11 s and 1.42 s, 95% CI 1.08 to 2.02 s, respectively (p=0.629). Laterality was also not different between limbs for accuracy, p=0.484, or reaction time, p=0.716, and did not correlate with PLP severity. No confounding variables predicted individual responses to MT. Therefore, one 10 min MT session does not affect laterality and is not effective as standard treatment for PLP in military lower limb amputees. However, substantial PLP improvement for one individual and resolution of a stuck phantom limb for another infers that MT may benefit specific patients. No correlation found between PLP and laterality implies associated cortical reorganisation may not be the main driver for PLP. Further research, including neuroimaging, is needed to help clinicians effectively target PLP.

Functional reorganisation and recovery following cortical lesions: A study in macaque monkeys

ABSTRACTDamage following traumatic brain injury or stroke can often extend beyond the boundaries of the initial insult and can lead to maladaptive cortical reorganisation. On the other hand, beneficial cortical reorganisation leading to recovery of function can also occur. Here, we used resting state FMRI (rsFMRI) to examine how functional connectivity in the macaque brain changed across time in response to lesions to the prefrontal cortex, and how this reorganisation correlated with changes in behaviour. Two monkeys were trained to perform location-based and object-based delayed match-to-sample tasks. We also collected rsFMRI data under general anaesthesia at two pre-lesion time-points, separated by 3-4 weeks. After two cycles of testing and scanning, the animals received a principal sulcus lesion followed by an additional 4 cycles of testing and scanning. Later, the same animals received a second lesion to the opposite hemisphere and additional cycles of testing and scanning.Both animals showed a marked behavioural impairment following the first lesion, which was associated with a decrease in functional connectivity, predominantly within frontal-frontal networks in both hemispheres. Approximately 8 weeks following the lesion, performance improved, as did functional connectivity within these networks. Following the second lesion, functional connectivity again decreased and this was associated with a marginal behavioural deficit that did not recover.Our data show that behavioural impairments reflect not just the removal of the lesioned area, but also disturbance to an extensive cortical network. This network can recover by restoring and/or strengthening pre-existing connections, leading to improvement in behaviour.

Perceptually relevant remapping of human somatotopy in 24 hours

Experience-dependent reorganisation of functional maps in the cerebral cortex is well described in the primary sensory cortices. However, there is relatively little evidence for such cortical reorganisation over the short-term. Using human somatosensory cortex as a model, we investigated the effects of a 24 hr gluing manipulation in which the right index and right middle fingers (digits 2 and 3) were adjoined with surgical glue. Somatotopic representations, assessed with two 7 tesla fMRI protocols, revealed rapid off-target reorganisation in the non-manipulated fingers following gluing, with the representation of the ring finger (digit 4) shifted towards the little finger (digit 5) and away from the middle finger (digit 3). These shifts were also evident in two behavioural tasks conducted in an independent cohort, showing reduced sensitivity for discriminating the temporal order of stimuli to the ring and little fingers, and increased substitution errors across this pair on a speeded reaction time task.

Brain Responses to Acupuncture Stimulation in the Prosthetic Hand of An Amputee Patient

This report describes the brain responses to acupuncture in an upper limb amputee patient. A 62-year-old male had previously undergone a lower left arm amputation following an electrical accident. Using functional MRI, we investigated brain responses to acupuncture stimulation in the aforementioned amputee under three conditions: (a) intact hand, (b) prosthetic hand (used by the patient), and (c) fake fabric hand. The patient described greater de qi sensation when he received acupuncture stimulation in his prosthetic hand compared to a fake hand, with both stimulations performed in a similar manner. We found enhanced brain activation in the insula and sensorimotor cortex in response to acupuncture stimulation in the amputee's prosthetic hand, while there was only minimal activation in the visual cortex in response to acupuncture stimulation in a fake hand. The enhanced brain responses to acupuncture stimulation of the patient's prosthetic hand might be derived from cortical reorganisation, as he has been using his prosthetic hand for over 40 years. Our findings suggest the possible use of acupuncture stimulation in a prosthetic hand as an enhanced sensory feedback mechanism, which may represent a new treatment approach for phantom limb pain.