Treating Intention In Aphasia: Neuroplastic Substrates

The purpose of this study is to determine if an "intentional act" improves treatment response for patients with nonfluent aphasia. The treatment involves naming pictures and saying members of categories. The "intentional act" requires initiating picture naming or category member trials with a left-hand movement sequence. Nonfluent aphasia is a disorder of language production in which patients with damage to the brain's language system have trouble initiating and maintaining spoken communication. All patients participating in the study take part in functional MRI scans to determine how treatments affect brain systems.

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.

aphasia, therapies, investigational, rehabilitation of speech and language disorders, magnetic resonance imaging, functional, language

Treats word-finding (picture naming, category member generation) with an intention manipulation (complex left-hand movement to initiate word-finding trials)

Word-finding trials (picture-naming) with intention manipulation (initiating word-finding trials with a complex left-hand movement). 8 (or more) baseline sessions over 4 days followed by 30 treatment sessions (2 sessions/day, 5 days/week for 3 weeks).

Word-finding trials with no intention manipulation. 8 (or more) baseline sessions in 4 days followed by 30 treatment sessions (2 sessions/day, 5 days/week for 3 weeks).

Functional MRI laterality indices (LIs)were calculated for lateral frontal, medial frontal, and posterior perisylvian cortex regions of interest (ROIs): L=number of active voxels in left hemisphere ROI and R=number of active voxels in right hemisphere ROI using the following formula: (L-R)/(L+R). LIs could vary from -1 (completely right lateralized) to +1 (completely left lateralized). Then, change in LIs was calculated by subtracting the pre-treatment from the post-treatment and 3-mo follow-up LI. It was expected the intention manipulation would show a rightward shift in LI.

Improvement for the time series from 8 baseline sessions through 30 treatment sessions for naming probes was computed with the C statistic using Tryon's (1982, 1983) formula for each subject. C statistics were converted to Z scores, using the formula provided by Tryon (1982). Z scores indicated treatment change for each subject, with a positive and significant Z score indicating substantive treatment gains. Z scores were then compared between groups with a t statistic. It was expected that the intention manipulation would lead to greater treatment gains than when it was not used.

Improvement for the time series from 8 baseline sessions through 30 treatment sessions for naming probes was computed with the C statistic using Tryon's (1982, 1983) formula for each subject. C statistics were converted to Z scores, using the formula provided by Tryon (1982). Z scores indicated treatment change for each subject, with a positive and significant Z score indicating substantive treatment gains. Z scores were then compared between groups with a t statistic. It was expected that the intention manipulation would lead to greater treatment gains than when it was not used.

Inclusion Criteria: Nonfluent aphasia caused by stroke Moderate to severe word-finding problems 6 or more months post stroke Right handed prior to stroke All strokes in left hemisphere Native English speaker Capable of following verbal directions Exclusion Criteria: Severe impairment of word comprehension Brain injury or disease in addition to stroke Drug or alcohol abuse within past 6 months Schizophrenia or other psychiatric disorder necessitating hospitalization History of learning disability Claustrophobia Cardiac pace-maker Ferrous metal implants not attached to bone, metal fragments in body Profound hearing loss

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