Adaptation is site-specific — moving the vibration source to a new patch of skin restores sensitivity

What it is

The dulling caused by sustained tactile stimulation at one patch of skin happens only on that patch — other parts of the body, and even neighboring skin on the same limb that was never directly stimulated, do not lose sensitivity. So when a haptic actuator worn at a fixed spot (a single vibration point on a wristband, say) starts feeling weaker after prolonged use, moving the vibration point a few centimeters to a fresh patch of skin restores something close to the original perceived strength almost immediately, with no need to wait for the fatigue to "wear off."

Why it happens

This follows directly from dulling being local rather than whole-body: the pathway that reports change responds based on whatever small receptive field was actually activated, and the dulling is essentially signal decay confined to that receptive field — it does not spread to neighboring receptive fields that were never stimulated. So switching to a patch of skin that this particular sustained stimulus never covered means the receptors there have been sitting at baseline the whole time, and should respond at roughly the strength the original site gave at first contact.

Studying it

A multi-actuator experiment works here: participants receive continuous vibration at a fixed point until they report clear dulling, then immediately receive an equal-intensity vibration at a nearby point, with detection threshold or intensity rating measured to see whether it returns to the pre-adaptation level, compared against a control condition where stimulation simply continues at the original spot — confirming that relocation genuinely restores sensitivity rather than the improvement being a placebo of expectation.

Where it stops holding

This holds when the dulling genuinely stems from local peripheral signal decay. If users have instead lost attention to this class of alert altogether — noticing it but no longer treating it as worth acting on — moving the contact point will not fix anything, because what's operating by then is no longer peripheral decay but a higher-level loss of response to the alert category, which relocating the actuator cannot touch. Also, if the new location is too close to the original (still within the same receptive field), the benefit is diminished — the displacement needs to be large enough to land in a genuinely different receptive field.

Applying it

• For devices worn long-term that output continuous tactile feedback (fitness bands, navigation belts), prefer a multi-actuator array that periodically rotates the stimulation point among several locations, rather than always driving the same single spot, where hardware allows it.
• If the hardware only has a single-point actuator, at minimum give users a simple, actionable suggestion — such as adjusting how the device sits — as an immediate remedy when sensitivity seems to have dropped.
• How to check: have participants wear a single-point actuator long enough to report dulling, then compare threshold changes between continuing at the same spot versus switching to a nearby fresh location, confirming a statistically visible recovery from relocation.

Related

• Same group: A4.08.1 A constant, unchanging tactile stimulus gets perceptually dulled · A4.08.2 A varying pattern stays effective longer than a constant intensity · A4.08.4 Peripheral receptor adaptation and central habituation are two different mechanisms with different recovery speeds · A4.08.5 Adaptation to one tactile mode does not fully transfer to another · A4.08.6 Sensitivity needs time to recover after a stimulus stops, so an immediate repeat cue lands with reduced effect
• Nearby: A4.02 Two-point discrimination threshold and its variation across body sites · A4.12 Tactile spatial resolution and cortical mapping
• Search terms: site-specific adaptation · actuator relocation · wearable haptic placement · receptive field