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Sensory Enrichment for Older Adults


This study will explore sensory stimulation, in the form of olfactory enrichment with essential oils, as a potential means of enhancing cognitive abilities, olfactory function, and quality of life.

Minimum Age Maximum Age Gender Healthy Volunteers
60 Years 85 Years All Yes
March 8, 2019
September 1, 2020

  • Normal cognition
  • Speak, read, and understand English fluently
  • Seeing and hearing ability adequate for neuropsychological and computerized testing
  • Good general health with no disease(s) expected to interfere with the study
  • Ability to smell scents
  • Willingness to refrain from using scented candles, scented oils, or air fresheners while participating in the study
  • Able to participate in a fMRI scan

  • Known fragrance sensitivities
  • Asthma, allergies, or a fragrance sensitivity that produces symptoms similar to those of an allergy, including runny nose, watery eyes, sneezing, or skin rash
  • Neurological disease such as Parkinson's disease, multiple sclerosis, brain cyst, tumor, or aneurysm
  • Major health conditions such as uncontrolled diabetes mellitus, uncontrolled hypertension, nutritional deficiency, or thyroid disease
  • Significant psychiatric disorders such as schizophrenia, bipolar disorder, anxiety disorder, or attention-deficit hyperactivity disorder
  • Cognitive impairment when tested at baseline (defined as a score on any neuropsychological test of 1.5 standard deviations or more outside the age norm)
  • Alcohol or substance abuse or dependence within the past 2 years
  • Smoke cigarettes, e-cigarettes, cigars, marijuana, or any other substance that could produce an interfering odor for the study
  • If interested in fMRI, contraindications to MRI such as pacemaker, aneurysm clips, artificial heart valves, ear implants, metal fragments or foreign objects in the eyes, skin or body

Participants will be randomly assigned to exposure to either a low or high concentration of essential oils, delivered by a nebulizer, nightly for 2 hours. They will rotate through seven different scents, one per night, for 6 months. Fifty of the participants will have a functional magnetic resonance imaging (fMRI) scan at the beginning and end of the study, which will be used to examine changes in the brain.

In mice, multi-odorant enrichment has been shown to increase neurogenesis in a critical memory pathway and improve memory. In this clinical study, we will determine if a nightly sensory enrichment regimen can improve cognitive skills in older adults, as measured by cognitive assessments and brain imaging. We also will determine if mood/mental state of mind or olfactory functioning improve following scent stimulation.

Name City State Zip Status Primary Contact
University of California Irvine
Irvine California 92697 Recruiting

University of California, Irvine

  • Procter and Gamble

Name Role Affiliation
Michael Leon, PhD Principal Investigator University of California, Irvine
Michael Yassa, PhD Principal Investigator University of California, Irvine

Name Phone Email
Blake A Miranda, BS 949-824-0904
Michael Leon, PhD 949-237-3026


Sensory Enrichment for Older Adults