  Tactile perception plays an important role in activities of daily living, and
it can be impaired in individuals with certain medical conditions. The most
common tools used to assess tactile sensation, the Semmes-Weinstein
monofilaments and the 128 Hz tuning fork, have poor repeatability and
resolution. Long term, we aim to provide a repeatable, high-resolution testing
platform that can be used to assess vibrotactile perception through smartphones
without the need for an experimenter to be present to conduct the test. We
present a smartphone-based vibration perception measurement platform and
compare its performance to measurements from standard monofilament and tuning
fork tests. We conducted a user study with 36 healthy adults in which we tested
each tool on the hand, wrist, and foot, to assess how well our smartphone-based
vibration perception thresholds (VPTs) detect known trends obtained from
standard tests. The smartphone platform detected statistically significant
changes in VPT between the index finger and foot and also between the feet of
younger adults and older adults. Our smartphone-based VPT had a moderate
correlation to tuning fork-based VPT. Our overarching objective is to develop
an accessible smartphone-based platform that can eventually be used to measure
disease progression and regression.
