[ISEA2009] Paper: Paul Martin Lester – When digital trumps analog: teaching with Second Life


It sounds like a horrible idea.
Put the head of a slightly anesthetized cat into a vice so that it’s forced to watch a simple slide show while you poke the back of its brain with a microelectrode. But that scene was not a horror movie plot that would give a member of PETA (the People for the Ethical Treatment of Animals) nightmares, two scientists won a Nobel Prize for that experiment in 1981.

The work of Canadian David Hubel and Swede Torsten Wiesel of the Johns Hopkins University in Baltimore, provided clues to how the brain sees images via our eyes. The two jabbed a microelectrode into a brain cell in the visual cortex at the back of the brain of an anesthetized cat and connected it to both an amplifier and an oscilloscope. The amplifier converted electrical energy to a ‘put-put’ sound while the oscilloscope turned signals to a blip on a screen so they could measure the response.

With the cat’s eyes open and focused toward a screen, the scientists flashed simple straight and slanted light patterns. With their set-up Hubel and Wiesel could see and hear immediately the effect of any nerve cell stimulation by the patterns of light. After they flashed the light on the screen several times and adjusted their equipment, the scientists recorded what they had thought was possible: the stimulated activity of a single brain cell responsible for vision.

  • Paul Martin Lester California State University, Fullerton, USA

Full text (PDF)  p.  426-432