AUTHOR=Aimonetti Jean-Marc , Deshayes Claire , Crest Marcel , Cornuault Pierre-Henri , Weiland Benjamin , Ribot-Ciscar Edith 

TITLE=Long Term Cosmetic Application Improves Tactile Discrimination in the Elderly; a New Psychophysical Approach

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=11

YEAR=2019

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2019.00164

DOI=10.3389/fnagi.2019.00164

ISSN=1663-4365

ABSTRACT=<p><bold>Introduction</bold>: Tactile sensitivity is impaired in older adults, which contributes to the loss of manual dexterity and mobility function. The reliability of classical psychophysical tests, such as two-point gap discrimination, has been questioned. Here we tested a new method to determine tactile acuity during dynamic touch, which is more functional than static touch. The aim was to validate a method providing a high level of discrimination of tactile acuity in the elderly.</p><p><bold>Methods</bold>: We tested the ability of subjects to evaluate the distance between bands printed on poly-methyl-methacrylate (PMMA) sheets. Pairs of sheets were compared in two groups of participants aged from 60 to 74 years; the test group was required to apply a cosmetic foam with an active ingredient on both their hands twice a day for 1 month, the control group had an identical task but used the same cosmetic foam without any active ingredient. The tests were run in a double-blind, placebo-controlled study.</p><p><bold>Results</bold>: The tactile discrimination threshold decreased by 83 μm after 1 month of cosmetic application in the group using the active ingredient, while it was unchanged in the control group.</p><p><bold>Discussion</bold>: The test presented here provided highly accurate results and should be useful to determine tactile performance. It allows the monitoring of tactile rehabilitation and/or skin treatments used to restore tactile acuity in the elderly.</p>