Author(s): Tiffany Field
During the last few decades a significant literature has evolved, suggesting that sensory dysfunction, particularly smell and taste dysfunction, can be early markers for neurodegenerative diseases such as Parkinson’s and Alzheimer’s and neuropsychiatric diseases including ADHD and Schizophrenia, all diseases that involve dopaminergic pathology. Smell loss and taste dysfunction appear in clinical versus non-clinical groups, and in longitudinal studies these symptoms have been noted years earlier than motor signs in the first degree relatives of individuals who already have the diseases. This paper is a review of the recent literature on empirical studies and reviews that have documented the results of sensory screenings of several groups with neurodegenerative and neuropsychiatric diseases and those first-degree relatives at risk for those diseases. Although early biomarkers could be useful in identifying those needing preventive intervention, the treatment literature is very limited.
