Improved naming after TMS treatments in a chronic, global aphasia patient--case report

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.

Figures

Fig. 1

T1-weighted structural MRI scan for this severe nonfluent/global aphasia patient (57yr. F, 6.5 yr. poststroke). The lesion is primarily subcortical only, without lesion in Broca’s or Wernicke’s cortical areas. Extensive lesion was present in the two white matter areas adjacent to ventricle compatible with severe nonfluent speech: 1) the medial subcallosal fasciculus located anterolateral to the L frontal born, deep to Broca’s area (vertical arrows); and 2) the middle 1/3 periventricular white matter located deep to sensorimotor cortex mouth, adjacent to the L body of lateral ventricle (horizontal arrow). See text for pathways in these areas. The L and R lateral views are reconstructed from the 3D MPRAGE MRI scan. The white triangle on the R pars triangularis marks the area of cortex (R BA 45) where 1 Hz rTMS was applied during each 20-minute treatment session (Phase 2), utilizing the Brainsight program to maintain consistent placement of the TMS coil (Fig. 2). The enlarged box shows this targeted area (R BA 45) is located rostral to the anterior, vertical (ascending) ramus of the Sylvian fissure.

Fig. 2

Illustration showing the TMS equipment and treatment procedure: a) An infrared camera is used to detect the position of the TMS coil; b) The figure 8-shaped TMS coil is placed on the participant’s scalp to affect brain cortex (approximately 1 cm × 1 cm) directly beneath the center of the coil; c) The 3D MPRAGE MRI scan of the participant is shown on a laptop computer to guide positioning of the TMS coil directly over the targeted cortical region of interest (Brainsight, Rogue Industries, Montreal, Quebec).

Fig. 3

Phase 1, Top: Location on this patient’s 3D MPRAGE MRI scan, for the four RH ROIs which were transiently suppressed for 10 minutes each, with 1 Hz rTMS during Phase 1. Middle: Her Snodgrass & Vanderwart (1980) naming scores as tested immediately post-rTMS to each RH ROI. Bottom: Her mean response time (RT) to name each picture, post-rTMS to each RH ROI. Only suppression of R BA 45 was associated with improved naming (and decreased RT) immediately post-rTMS.

Fig. 4

Phase 2. Graphs showing BNT and BDAE naming scores for this global aphasia patient pre-rTMS (6.5 years poststroke) and at 2 months and 8 months after 10, 20 minute, 1 Hc rTMS treatments to RBA 45.