Frank Stella famously said “what you see is what you see.” He wanted to stay close to perception and not stray too far into literary or personal interpretations. My title, cribbed from an article in Science, refers not to the invasion of personal emotion, but about the recently experimentally observed influence of literal, tactile touch sensations on visual experience.

Stare at a waterfall long enough, and nearby stationary objects such as rocks and trees will seem to drift up. The optical illusion is called motion aftereffect, and it may trick more than just your eyes, according to a new study. When subjects watched a stationary stripe on a computer screen after a machine stroked their fingertips, the motion of the stroking created the illusion that the stripe was moving. The discovery demonstrates for the first time a two-way crosstalk between touch and vision, challenging long-held notions of how the brain organizes the senses.

I guess the neuroscience of what’s involved here may similar to the sight-sound synaesthesia we’ve discussed before (see comments discussions here and especially here). But this is the first I’ve heard of a tactile version of it. Has anybody out there had experiences along those lines? Other than seeing stars when you bump your head?