Application of the Granger causality model for the study of effective connectivity from functional magnetic resonance images acquired during verbal, visual and operating memory experiments in healthy subjects and patients with refractory epilepsy
The main objective of this project is to apply the technique known as Granger causality analysis to functional magnetic resonance imaging (fMRI) data from three distinct groups: (1) normal individuals (controls), (2) patients with Mesial Temporal Lobe Epilepsy (MTLE) and (3) patients with Frontal Lobe Epilepsy (FLE). All individuals will be submitted to an fMRI exam with presentation of long-term (verbal and visual) memory and working memory paradigms. A search of the literature shows a gap with respect to the use of this tool for analysis of the mentioned memory types, in particular, regarding the relation between verbal, visual and operational memory studies in groups of epilepsy patients. More specifically, our main goal is to apply this approach to the study of the effective connectivity between brain regions involved in the processing of verbal, visual and operational memories, in order to better understand the way in which MTLE and FLE affect the brain connections of patients, through comparison with the fMRI exams of the control group. We also want to compare the results obtained with Granger causality with results obtained using another technique of effective connectivity estimation, the so called dynamic causal modeling (DCM). This would allow to better evaluate the advantages and disadvantages of the Granger causality model. Another goal of this work, after the application of Granger causality in epilepsy is verified, is to extend the use of this technique to other neurological diseases.
News published in Agência FAPESP Newsletter about the scholarship: