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Jerome Lettvin1

Jerome Ysroael Lettvin (born Chicago, February 23, 1920) is a cognitive scientist and professor Emeritus of Electrical and Bioengineering and Communications Physiology at the Massachusetts Institute of Technology (MIT).

In 1967, Jerry debated Timothy Leary about the merits of LSD. Jerry hurled the timeless epithet "BULLSHIT!" at Leary, who was sitting in the lotus position near a candle. This in response to Leary (a licensed psychologist) characterizing the frank symptoms of temporal lobe epilepsy as a religious experience.

Jerome Lettvin's Unusual Experiments1

vertebrate axons exhibit sub-millisecond triphasic spikes;
action potentials are found at nodes of Ranvier but absent in Remak fibers

a cut optic nerve trained to the olfactory lobe regrows, remapping the retina;
senses appear to direct brain growth rather than the reverse

axonal stimulation backfires into the cell body;
action potentials can travel from axons to the axon hillock and into the cell

stimulating the bulbo-reticular inhibitory system stops strychnine convulsions;
reflexes have system-wide attenuation controls

axon pulse intervals can be separated into bands;
some form of information is encoded in pulse intervals

color constancy derives from boundaries and vertices in motion over the retina;
color is not related to wavelength

images stationary on the retina fade to invisible;
movement is critical to vision

visible insects cause no nervous activity in a frog that sees a duck;
attention obeys hierarchical rules


  1. Jerome Lettvin