 Introduction Assessments of mechanical skin sensitivity include psychophysical responses to stimulation with calibrated polyamide monofilaments. Although the theoretical background and the application of monofilaments are straightforward, inconsistencies of the method have been reported in the literature. One of the applications of polyamide monofilaments are the assessments of magnitude of secondary hyperalgesia areas SHAs, i.e. areas in normal skin near an injury with increased mechanical sensitivity. Secondary hyperalgesia is a measure of central sensitization and reflects the effect of an injury on the central nervous system. The objective of the study is to investigate the hypothesis, based on previous studies, that a light tactile stimulus delineates a larger SHA than stimulation with a more rigid monofilament. 