During the last decade occurred brisk development of the method of functionalMRwhich maps regional changes of cerebral perfusion and indirectly assesses also the neuronal activationin the examined parts of the brain. Its contribution to investigations of cognitive functions is not quite unequivocal so far. Using the method of „event-related“ functionalMR(efMRI) the authors examinedthe auditory „oddball“ task in 10 healthy volunteers. They compared the assembled results with the results of previous efMRI and intracerebral ERP studies with the objective to evaluate the extent of agreement between areas with a haemodynamically significantly different response to rare target stimuli and known intracerebral generators of the P3 potential. Both methods proved the activation of several areas in particular the parietal and frontal lobe (lobulus parietalis superior, inferior, gyrus suprarginalis, gyrus cinguli, of the lateral prefrontal cortex, gyrus temporalis superior and of the thalamus). Consistent with the assumed significant role of the neurocognitive network for directed attention in the course of detection of target stimuli in the majority of these structures a more marked haemodynamic response was observed on the right side. Against expectation in the presented experiment nor in any previous efMRI studies a significant haemodynamic response to target stimuli was not proved at the site of the most marked P3 generator in the amygdalohippocampal complex.Different results were also obtained on examination of further areas, e.g. the rostral cingulum. Thus although the contribution of efMRI to recognition of the neuroanatomical correlate of mental processes is extremely high, it is unable to provide alone a complete map of activated cerebral areas in the course of cognitive operations. The reason is most probably the inability to reflect fully transient short-term functional changes of the neuronal populations. Thus it has to be conceived also in future as a complementary method and its results must be evaluated with maximum caution.

        Key words: oddball, event-related fMRI, SPM, genesis of P3