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Background: Little is known about the regions involved in recovery from global aphasia in patients with malignant infarction after decompressive hemicraniectomy. This study reports a case of brain activation during speech perception in a right-handed patient with a massive left hemispheric infarction. Methods: Decompressive hemicraniectomy was performed in a 20-year old woman with space-occupying infarction of the speech dominant hemisphere. Complete anterior, middle and part of the posterior cerebral artery territories of the left hemisphere, as well as posterior regions of the right middle cerebral artery territory, were affected. Neuropsychological testing and functional magnetic resonance imaging (fMRI) during speech perception were performed 10 months after stroke. Results: The patient was able to walk, go up and down stairs independently and perform simple tasks at home. She was also well able to match visually and orally presented words with their corresponding pictures, despite large bilateral lesions in the posterior regions. fMRI revealed strong activation of the left temporo-occipital and parieto-occipital areas. In the right hemisphere was observed a small area of activation in the posterior part of the superior and middle temporal gyrus. Conclusions: In aphasic patients, the activation of posterior bilateral associative areas might be used to support language perception. [ABSTRACT FROM AUTHOR]

Recent neuroscientific findings suggest that functional magnetic resonance imaging (fMRI)-based brain–computer interfaces may be a viable strategy for detecting covert awareness in patients clinically diagnosed as being in a vegetative state. This research may open a promising new avenue for developing neuroimaging techniques that provide prognostic and diagnostic information that complements current behavioral tests for assessing disorders of consciousness, thereby increasing the effectiveness of diagnostic screening. These techniques may also permit patients who are behaviorally nonresponsive yet retain high levels of preserved cognition to meaningfully engage in clinical decision making. Before this application can occur, certain ethical issues associated with decision-making capacity must be addressed. Although it is not currently possible to assess decision-making capacity through neuroimaging methods, it may be in the future, provided that certain conceptual and empirical steps are taken to demonstrate that brain–computer interfaces satisfy requisite criteria of capacity assessment. In this article we lay out the conceptual foundations for a mechanistic explanation of capacity that would allow the necessary empirical steps for incorporating neuroimaging techniques into the standard capacity assessment battery utilized in clinical practice. [ABSTRACT FROM AUTHOR]

Primary objective: To study cerebral response in a functional magnetic resonance imaging (fMRI) task of speech perception in a sample of patients in vegetative state (VS) and minimally conscious state (MCS) after traumatic brain injury. Methods: Three patients in VS, four patients in MCS and 19 healthy volunteers were enrolled for the study. All subjects underwent an fMRI task of passive listening of narratives played forward and backward, alternated with periods of silence. This study analysed cerebral response to language and to complex sound processing in the healthy subjects' group and in each patient, using SPM5. Results: One patient in VS and one in MCS showed cerebral responses to language and to complex sound very similar to those shown by the healthy volunteers. Two more patients, one in VS and one in MCS, showed significant responses to complex sound only. Finally, one patient in VS and one patient in MCS failed to show significant activation in response to either stimulus. Conclusions: Some patients in VS and MCS can preserve cerebral responses to language and auditory stimuli. fMRI may be useful to identify these responses, which may pass unnoticed in a bedside examination. [ABSTRACT FROM AUTHOR]