After pulsed peripheral olfactory impulses it is possible, under suitable testing conditions, for specific sensory potentials to be read from the surface of the skull and, after repetitions, added up (olfactorially evoked cortical potentials). Typically, there developes a so-called twin-potential containing the equivalents of the electrical activites of the nervus trigeminus and the nervus olfactorius in two peaks of the cortex equivalents. In an objective manner, in other words without intentional or vegetative influence by the test person, it is possible by the weakening or lack of one or the other or both part-potentials to obtain information about the functioning of the olfactory sense. Typical examples will be presented.