ABSTRACT
We report improved ability to name pictures at 2 and 8 months after repetitive transcranial magnetic stimulation (rTMS) treatments to the pars triangularis portion of right Broca's homologue in a 57 year-old woman with severe nonfluent/global aphasia (6.5 years post left basal ganglia bleed, subcortical lesion). TMS was applied at 1 Hz, 20 minutes a day, 10 days, over a two-week period. She received no speech therapy during the study. One year after her TMS treatments, she entered speech therapy with continued improvement. TMS may have modulated activity in the remaining left and right hemisphere neural network for naming.
Subject(s)
Aphasia/therapy , Electric Stimulation/methods , Magnetics , Pattern Recognition, Visual/radiation effects , Aphasia/rehabilitation , Basal Ganglia/pathology , Basal Ganglia/radiation effects , Chronic Disease , Female , Follow-Up Studies , Functional Laterality/physiology , Humans , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Middle Aged , Neuropsychological Tests/statistics & numerical data , Pattern Recognition, Visual/physiology , Speech Therapy/methods , Time FactorsABSTRACT
Functional imaging studies with nonfluent aphasia patients have observed "over-activation" in right (R) language homologues. This may represent a maladaptive strategy; suppression may result in language improvement. We applied slow, 1 Hz repetitive transcranial magnetic stimulation (rTMS) to an anterior portion of R Broca's homologue daily, for 10 days in four aphasia patients who were 5-11 years poststroke. Significant improvement was observed in picture naming at 2 months post-rTMS, with lasting benefit at 8 months in three patients. This preliminary, open trial suggests that rTMS may provide a novel treatment approach for aphasia by possibly modulating the distributed, bi-hemispheric language network.
Subject(s)
Aphasia/rehabilitation , Electric Stimulation Therapy , Frontal Lobe/physiology , Functional Laterality/physiology , Magnetics , Aphasia/physiopathology , Aphasia/therapy , Chronic Disease , Female , Humans , Male , Middle Aged , Pattern Recognition, Visual , Semantics , Treatment OutcomeABSTRACT
Functional brain imaging with nonfluent aphasia patients has shown increased cortical activation (perhaps "overactivation") in right (R) hemisphere language homologues. These areas of overactivation may represent a maladaptive strategy that interferes with, rather than promotes, aphasia recovery. Repetitive transcranial magnetic stimulation (rTMS) is a painless, noninvasive procedure that utilizes magnetic fields to create electric currents in discrete brain areas affecting about a 1-cm square area of cortex. Slow frequency, 1 Hz rTMS reduces cortical excitability. When rTMS is applied to an appropriate cortical region, it may suppress the possible overactivation and thus modulate a distributed neural network for language. We provide information on rTMS and report preliminary results following rTMS application to R Broca's area (posterior, R pars triangularis) in four stroke patients with nonfluent aphasia (5-11 years after left hemisphere stroke). Following 10 rTMS treatments, significant improvement in naming pictures was observed. This form of rTMS may provide a novel, complementary treatment for aphasia.
Subject(s)
Aphasia/therapy , Language , Mental Processes/physiology , Transcranial Magnetic Stimulation , Dominance, Cerebral , Electric Stimulation , Frontal Lobe/physiology , Humans , Reaction Time/physiologyABSTRACT
Cortical reorganization in poststroke aphasia is not well understood. Few studies have investigated neural mechanisms underlying language recovery in severe aphasia patients, who are typically viewed as having a poor prognosis for language recovery. Although test-retest reliability is routinely demonstrated during collection of language data in single-subject aphasia research, this is rarely examined in fMRI studies investigating the underlying neural mechanisms in aphasia recovery. The purpose of this study was to acquire fMRI test-retest data examining semantic decisions both within and between two aphasia patients. Functional MRI was utilized to image individuals with chronic, moderate-severe nonfluent aphasia during nonverbal, yes/no button-box semantic judgments of iconic sentences presented in the Computer-assisted Visual Communication (C-ViC) program. We investigated the critical issue of intra-subject reliability by exploring similarities and differences in regions of activation during participants' performance of identical tasks twice on the same day. Each participant demonstrated high intra-subject reliability, with response decrements typical of task familiarity. Differences between participants included greater left hemisphere perilesional activation in the individual with better response to C-ViC training. This study provides fMRI reliability in chronic nonfluent aphasia, and adds to evidence supporting differences in individual cortical reorganization in aphasia recovery.
