Percept adaptation to ICMS (fading)

The attenuation or fading of an ICMS-evoked percept during sustained or repeated stimulation. A train held at constant amplitude tends to lose salience over seconds, and closely spaced trains can show reduced response, phenomena that are analogous to natural sensory adaptation but arise from a different, cortically-driven substrate and can be more pronounced.

Adaptation complicates using ICMS as a steady-state indicator, for instance signalling continuous contact force, because a constant stimulus does not evoke a constant sensation. It is one of the physiological reasons that time-varying and biomimetic encodings, which emphasize transients at stimulus events and insert quiet intervals, tend to outperform tonic intensity coding for conveying object interaction.