[Smell: integrating neurodegeneration and autoimmunity - a personal view].

Throughout human evolution, smell lost its important role to be replaced by other senses. Although, it retained a "role"in several "healing" practices. The aim of this review was to analyze the possible roles and influences of olfaction on higher brain functions, like mood and memory, and in contrast heightened the influence of pathologies such as Alzheimer's disease and schizophrenia on the olfactory function, based on recent animal and human data. In this neuro-psychiatric approach, the immune system could have a central role.