Currently, clinical examination of olfaction is not so familiar as vision, audition or tactile sensation, because of its difficulties in stimulus presentation. Objective diagnoses for diseases are also well developed in vision, audition and touch sensation. For olfaction, however, the situation is still poor. On the other hand, recent studies reveal that hyposmia is frequently observed in early stages of Alzheimer's disease or Parkinson's disease.

AIST has developed objective and subjective diagnostic methods for olfaction. We utilized olfactory event related magnetic fields of the brain for objective olfactory diagnosis. Five healthy participants and four anosmia patients were diagnosed using T & T olfactometry and intravenous olfactometry. We presented β-phenylethylalcohol in forty trials, with 400 milli seconds stimulus period, and inter-stimulus interval was thirty seconds. And we discovered clear change in the magnetic field of the healthy participants but not with the patients. This diagnosis method will be useful for the clarification of the mechanism for olfactory loss and degenerative neurologic disease.