Cognitive impairments are a costly consequence of an aging population and a major challenge for health services in the 21st century. To tackle this challenge, we need to combine the understanding of the human cognitive system and its impairments (cognitive neuroscience), measures of brain function (neuroimaging), and the challenges faced by patients and clinicians (clinical neuropsychology). Aphasia ¿ difficulties with speech and language following a stroke ¿ represents a perfect example of a very debilitating disorder where such an integration is both lacking and much needed. Speech and language therapy is effective to ameliorate aphasia in general, but with a strong inter-individual variability. We still do not understand why some patients improve and some others do not. The present proposal is a development of one work package of the WinAphasia ITN project, which was aimed at developing a new rehabilitation platform and new prognostic markers of recovery by assessing the likelihood of therapy gains given the initial behavioral and neurological profile of the patient. Here we aim at identifying a set of neurostructural and neurofunctional parameters, obtained through state-of-the-art magnetic resonance imaging, which predicts the severity of language disorders in the post-acute stage and the degree of therapy-induced recovery. The results of this project will allow, for the first time, to analyze the sensitivity of different neuroimaging markers for predicting behavioral measures of change. This, in turn, will provide valuable information about which measure can be used to evaluate treatment efficacy.
The originality and novelty of the project rely on the identification of specific neuroimaging markers of language recovery. The project will significantly contribute to the ongoing debate on the neural correlates of language recovery by providing a richer, multimodal dataset including not only the traditional lesion volume/location analyses, but also functional indices of network topology and of its degree of disruption, following the most recent approaches in the functional connectivity literature [18]. As it¿s more and more common in the neuroimaging community, we will publicly release the raw neuroimaging and behavioral data (after anonymization and deidentification) and the processing pipelines, thus contributing to further progress by the community.
Combining pre-treatment information about brain lesions from MRI/fMRI with measures of brain connectivity will allow more accurate predictions of potential therapy gains. The characterization of the neuro-structural baseline conditions that are associated with successful language recovery will provide useful predictive markers of recovery. The results will help us understand why some patients improve and others do not, and thus indirectly contribute to identifying novel treatments for special categories of aphasic patients. Extending the behavioural examination to the relationships between language and the sensory-motor system will also allow us to evaluate embodied approaches to language and their potential to give useful contributions to the development of novel therapeutic approaches.
Neuroimaging indices of a better recovery and a good therapy efficacy are an invaluable instrument for the clinicians in order to select individualized therapy protocols and to evaluate behavioral outcomes. The collaboration with Aston University will also allow us to use an innovative language treatment program and to pursue the synergies underlying the original WinAphasia ITN project, thus increasing our chances to participate to collaborative EU calls in the next future.
Notes
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