Abstract The aim of functional brain magnetic resonance imaging studies is to determine which regions of the brain are related to a given specific task. Different methods can be used to extract the functional signal and there is currently no consensus for this operation. Measures based on correlation are only relevant for a single task. In this paper, we propose a method based on a multivariable Student's t test that permits the comparison of the results of successive activations. This technique allows a qualitative analysis of complex tasks, making possible to deal with both similar and different activated cortical areas.