1. A method for detection of emotional stress of a human subject in response to cognitive stimuli by measuring variations in pressure distribution across said subject's footprint, said method comprising the steps of causing the subject to apply force on a flat surface, said surface embedding a plurality of pressure sensitive sensors; connecting said pressure sensitive sensors to a signal analysis processor; presenting the subject with cognitive stimuli his disposition to which is of interest in the context of a given interview; monitoring variations in pressure distribution between said sensors; filtering the variation signals to reduce the effect of pressure variations caused by causes other than emotional stress; and matching the filtered variation signals to a pattern that represent emotional stress.