Nerve Journey (aka Sensation Speed)
Exploratorium, San Francisco

user research: formative
cited in: Exhibit Designs for Girls’ Engagement

Try having a friend tap your ankle and neck, simultaneously and rhythmically, about once per second. You'll be surprised to discover the sensations don’t feel simultaneous. Sensations from your ankle take 20-50 milliseconds longer to arrive in consciousness than from your closer-to-the-brain neck; a difference long enough to notice!

This inspired me to invent an electro-mechanical tapping machine, enabling visitors to experiment with actually timing sensations in their own bodies, by reversing the effect. Visitors turn a knob to adjust the precise delay between taps (at their ankle and neck) until both feel simultaneous. Then, an LCD display shows how long the actual delay they've settled upon is.

A very strange “aha” moment comes if one later reaches out and touches each tapper with a different hand. Since hand-to-brain nerve distances are equal for both arms, one feels the actual delay you just dialed-in, in stark contrast to how simultaneous it felt at your neck and shoulder!

In collaboration with Diane Whitmore.