The peanut butter test is interesting. For sufferers of early onset Alzheimer&#x27;s, the range at which you can detect a smell is different between your left and right nostrils. They used Peanut Butter in this test done by the University of Florida.<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Peanut_butter_test" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Peanut_butter_test</a>