The present invention relates to a cosmetic process for treating wrinkled skin, in particular the skin of the face and/or of the forehead, through a dermo-decontracting effect, comprising the topical application to said skin of a composition comprising, in a physiologically acceptable medium, at least one piperidine derivative chosen from the compounds of formula (I). These compounds make it possible to combat expression wrinkles according to a mechanism of dermo-decontraction. ##STR00001##