Treating Intention In Aphasia: Neuroplastic Substrates

A new treatment manipulating intention substrates for language production in "nonfluent" aphasia patients was developed. The intention component involves initiating word-finding trials with a complex left-hand movement. The study addresses (1) whether or not the intention manipulation (complex left-hand movement) makes a unique contribution to treatment outcome and (2) whether or not the intention manipulation helps to shift word production mechanisms from the left to the right frontal lobe. All study participants take part in functional magnetic resonance imaging (fMRI) scans of word-finding before and after treatment and at 3-month follow-up to measure changes in lateralization of frontal lobe activity during word finding. Only patients with a substantial degree of left frontal activity on the pre-treatment fMRI scan can participate. There are three specific aims: (1) to determine if repetitive initiation of word production with a complex left-hand movement leads to increased right-hemisphere lateralization of frontal activity and if these changes can be attributed to the intention component of treatment, (2) to determine whether activity in posterior perisylvian cortices that is entrained to right frontal activity shows a greater increase in right-hemisphere lateralization from pre- to post-treatment fMRI when the intention component is included in treatment, and (3) to determine whether onset of hemodynamic responses (HDRs) in right motor/premotor cortex becomes more closely associated with the temporal onset of participants' spoken responses across treatment when the intention component is included in treatment. If successful, the treatment can provide a new treatment vehicle for increasing language function in patients with "nonfluent" aphasia.