neuroplasticity and rehabilitation strategies robert k. shin m.d. va ms center of excellence...
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Neuroplasticity and Rehabilitation Neuroplasticity and Rehabilitation StrategiesStrategies
Robert K. Shin M.D.Robert K. Shin M.D.VA MS Center of ExcellenceVA MS Center of Excellence
Assistant ProfessorAssistant ProfessorDepartments of Neurology and OphthalmologyDepartments of Neurology and Ophthalmology
University of Maryland School of MedicineUniversity of Maryland School of Medicine
Neuroplasticity?Neuroplasticity?
The ability of cortex to reorganize in response to The ability of cortex to reorganize in response to injuryinjury
QuestionQuestion
Is the brain compensating for damage from MS in Is the brain compensating for damage from MS in order to maintain normal function?order to maintain normal function?
Functional MRIFunctional MRI
BOLD contrast analysisBOLD contrast analysis
– OxyhemoglobinOxyhemoglobin
– DeoxyhemoglobinDeoxyhemoglobin
Alternating periods of task vs. restAlternating periods of task vs. rest
Activated regions determined statisticallyActivated regions determined statistically
Reddy et al. Neurology 2000;54:236-244
A dynamic cortical response?A dynamic cortical response?
Initially increased activation of contralateral Initially increased activation of contralateral sensorimotor cortexsensorimotor cortex
Ipsilateral activation seen initially as wellIpsilateral activation seen initially as well
Activation gradually reduced as patient recoveredActivation gradually reduced as patient recovered
Clinically isolated syndromeClinically isolated syndrome
16 consecutive patients with a CIS suggestive of 16 consecutive patients with a CIS suggestive of multiple sclerosismultiple sclerosis
15 age- and sex-matched controls15 age- and sex-matched controls
Functional MRI during finger flexionFunctional MRI during finger flexion
Rocca et al. NeuroImage 2003;18:847-855Rocca et al. NeuroImage 2003;18:847-855
Rocca et al. NeuroImage 2003;18:847-855Rocca et al. NeuroImage 2003;18:847-855
A response to cortical pathology?A response to cortical pathology?
Decreased NAA found in clinically stable Decreased NAA found in clinically stable CIS patientsCIS patients
Increase in activation of somatomotor cortex Increase in activation of somatomotor cortex correlated with worsening brain damagecorrelated with worsening brain damage
Another puzzleAnother puzzle
Optic neuritis causes vision loss and prolonged Optic neuritis causes vision loss and prolonged VEPsVEPs
Vision in optic neuritis almost always recoversVision in optic neuritis almost always recovers
VEPs frequently remain abnormalVEPs frequently remain abnormal
QuestionQuestion
Is the brain somehow compensating for impaired Is the brain somehow compensating for impaired optic nerve function?optic nerve function?
Recovery from optic neuritsRecovery from optic neurits
7 patients who had recovered from optic neuritis7 patients who had recovered from optic neuritis
7 controls7 controls
Functional MRI during photic stimulationFunctional MRI during photic stimulation
Werring, et al. JNNP 2000;68:441-449Werring, et al. JNNP 2000;68:441-449
Werring, et al. JNNP 2000;68:441-449Werring, et al. JNNP 2000;68:441-449
Functional reorganization?Functional reorganization?
Only occipital activation seen in controlsOnly occipital activation seen in controls
Additional extra-occipital areas were activated in Additional extra-occipital areas were activated in patients who had recovered from optic neuritispatients who had recovered from optic neuritis
Attention and memoryAttention and memory
22 patients with RR-MS22 patients with RR-MS 22 age-matched controls22 age-matched controls
Functional MRI studyFunctional MRI study– Paced Auditory Serial Addition Test (PASAT)Paced Auditory Serial Addition Test (PASAT)– Recall taskRecall task
Mainero, et al. NeuroImage 2004;21:858-867Mainero, et al. NeuroImage 2004;21:858-867
Mainero, et al. NeuroImage 2004;21:858-867Mainero, et al. NeuroImage 2004;21:858-867
PASAT
Mainero, et al. NeuroImage 2004;21:858-867Mainero, et al. NeuroImage 2004;21:858-867
Recall
Mainero, et al. NeuroImage 2004;21:858-867Mainero, et al. NeuroImage 2004;21:858-867
T2 LL
An adaptive mechanism?An adaptive mechanism?
Altered activation during cognitive tasks in MS Altered activation during cognitive tasks in MS patientspatients
Activation increases as T2 lesion load increases Activation increases as T2 lesion load increases
But activation is greater in patients with better But activation is greater in patients with better functionfunction
ConclusionsConclusions
Functional MRI activity is altered in MS Functional MRI activity is altered in MS patientspatients
These changes appear to be an adaptive These changes appear to be an adaptive response to brain damageresponse to brain damage
Implications for rehabilitation?Implications for rehabilitation?
Can functional MRI be used to prognosticate?Can functional MRI be used to prognosticate?
Can “cortical plasticity” be enhanced?Can “cortical plasticity” be enhanced?– Proprioceptive stimulationProprioceptive stimulation
– Forced useForced use
– Neurotrophic factorsNeurotrophic factors
– Increased neurotransmitter releaseIncreased neurotransmitter release