The goal of the work described in this proposal is to provide a neuroimaging-based examination of the mechanisms of aphasia treatment and recovery. We propose to use functional magnetic resonance imaging together with structural and perfusion MR imaging as tools for tracking, recording and evaluating brain behavior changes linked to treatment-based changes in four experiments. We propose to systematically examine both behavioral and (correlated) neural effects of treatment while manipulating several critical patient-based and treatment-based variables that have been hypothesized to be relevant to aphasia recovery. The patient-related variables we will study include site and extent of lesion, in patients with anterior vs. posterior lesions, in early post-stroke vs. late post-stroke (chronic) stages of recovery. We propose to study the effects of treatment (vs. placebo-treatment) for these patients with a focus on both comprehension and production deficits in sentence level processing, comparing: two different treatment-intensity schedules (intensive vs. extended) and two different complexity-of-treatment conditions (training complex-to-simple vs. simple-to-complex structures). Our focus on this latter variable is based on our previous work showing that the former (complex-to-simple training) results in greater efficacy of treatment and generalization effects as compared to the latter. Additionally, we propose behavioral studies that extend examination of this 'complexity-of treatment' hypothesis into new domains of language processing and new populations (posteriorly lesioned patients with Wernicke's aphasia). Overall, we propose to employ (and replicate) treatment methods with previously demonstrated behavioral efficacy so as to provide a solid basis for examining (via neuroimaging) brain-based changes associated with a range of critical patient-based and treatment-based variables during treatment. Additionally, we propose to examine theoretically motivated extensions of the complexity method to new domains of language treatment. ? ?
