A Behavioral Manipulation Engages Right Frontal Cortex During Aphasia Therapy

Neurorehabil Neural Repair. 2014 Jul;28(6):545-53. doi: 10.1177/1545968313517754. Epub 2014 Jan 9.


Background An aphasia treatment was designed to shift laterality from the left to right lateral frontal lobe during word production by initiating word-finding trials with complex left-hand movements. Previous findings indicated successful relateralization. Objective The current study was designed to ascertain whether the shift was attributable to the left-hand movement. Methods Using stratified random sampling, 14 subjects were equally divided between Intention (IT) and Control (CT) treatments. CT was identical to IT, except with no left-hand movements. Both treatments trained picture naming (phases 1 and 2) and category-member generation (phase 3), each phase lasting 10 sessions. Functional magnetic resonance imaging of category member generation occurred at pretreatment, posttreatment, and 3-month follow-up. Results IT shifted lateral frontal activity rightward compared with pretreatment both at posttreatment (t = -2.602, df = 6, P < .05) and 3-month follow-up (t = -2.332, df = 5, P < .05), but CT did not. IT and CT yielded similar changes for all picture-naming and category probes. However, IT patients showed gains for untrained category (t = 3.33, df = 6, P < .01) and picture-naming probes (t = 3.77, df = 5, P < .01), but CT patients did not. Conclusions The rightward shift in lateral frontal activity for IT was because of the left-hand movements. IT evoked greater generalization than CT.

Keywords: aphasia; fMRI; magnetic resonance imaging; neuronal plasticity; rehabilitation; rehabilitation of speech and language disorders.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aphasia / rehabilitation*
  • Brain Mapping / methods*
  • Concept Formation / physiology
  • Female
  • Follow-Up Studies
  • Frontal Lobe / diagnostic imaging
  • Frontal Lobe / physiopathology*
  • Functional Laterality / physiology
  • Generalization, Psychological / physiology
  • Hand
  • Humans
  • Language Therapy / methods*
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Motor Activity / physiology*
  • Pattern Recognition, Visual / physiology*
  • Psychomotor Performance / physiology*
  • Treatment Outcome