FMRI IN AD · A functional neuroimaging study of face processing in early Alzheimer's disease
FP6 — Marie Curie Actions (Human Resources and Mobility)
- Duration
- 2008-06-01 → 2010-05-31
- EU contribution
- €80,000
- Participants
- 1
- Scheme
- IRG
Lines connect the coordinator with its partners.
Results in brief
Final Activity and Management Report Summary - FMRI IN AD (A functional neuroimaging study of face processing in early Alzheimer's disease)
Patients with Anterior temporal lobe (ATL) lesions show semantic and lexical retrieval deficits and the differential role of this area in the two processes is debated. Functional neuroimaging in healthy individuals has not clarified the matter mainly because of two reasons: - first, semantic and lexical processes occur usually simultaneously and automatically, and cannot easily be dissociated; - second susceptibility artifacts in ATL interfere with detection of task related Blood-oxygen-level-dependent (BOLD) signal changes. We devised a 'functional Magnetic resonance imaging' (fMRI) paradigm, which allowed us to study the identification (i.e. association of semantic biographical information) of celebrities, with and without the ability to retrieve the proper name. Further, to reduce susceptibility artefacts in ATL, we established an optimised Echo planar imaging sequence (EPI), reaching reliable BOLD-signal sensitivity in all areas of the parietal and temporal lobes. While semantic retrieval reliably activated the left ATL among other areas, only more posterior areas in the temporal lobe and temporo-parietal junction were modulated by naming. These results support the data from patients with ATL lesions and indicate that the anomia that they often experience is due to semantic rather than lexical retrieval impairment.
Data: CORDIS, © European Union
Project objective
The present project proposes to combine neuropsychology and modern neuroimaging techniques to investigate the structural damage and the retained functionality of the brain in patients at early stages of Alzheimer's disease. We plan to analyse the neural basis of semantic and lexical processes by concentrating on the particular case of person-specific information, i.e. knowledge about known faces and proper names.The study of face recognition and person-specific semantic knowledge provides a unique model to investigate how the human brain analyses incoming stimuli and links them to information stored in long-term memory. Brain damaged patients have demonstrated selective deficits in retrieving semantic and lexical information from both faces and proper names. More recently, functional imaging studies on normal subjects have concentrated on the neural substrates of certain aspects of face processing.This considerable amount of research has provided:i) a robust cognitive model of face and proper name processing, andii) the outline of a network of brain regions involved in the process.However, inevitable limitations of the lesion-deficit association model and of functional neuroimaging on normal subjects, have undermined the possibility to further specify the relative contribution of the different brain regions within this network.Correlating the degree of brain atrophy and the pattern of functional activation of damaged and undamaged areas with the cognitive deficit we aim to:i) identify a pattern of structural damage and of functional preservation typical of the initial stages of Alzheimer's disease, andii) gain important clues on the organisation of semantic and lexical information in the human brain.
Original text from CORDIS.
Participants
- UNIVERSITÀ DEGLI STUDI DI TRENTO · TRENTOCoordinatorItaly
Links
Data: CORDIS, © European Union