1931 — The Psycograph, a device consisting of a helmet and movable rods designed so measurements could be made at 32 points on the skull, made its public debut at the Twin City Auto Show. The device was an excursion into automated phrenology.
1961 — A chimpanzee named HAM performed a series of operant avoidance tasks during a space flight that was part of Project Mercury, the first American manned space flight program. HAM, trained by Richard Belleville, contended with two schedules of bar-pressing for shock avoidance. In an 18-minute suborbital flight, HAM made only two errors.
1966 — The journal Multivariate Behavioral Research was first published by the Society of Multivariate Experimental Psychology. Desmond S. Cartwright was the journal's editor.
1969 — Neal E. Miller's article "Learning of Visceral and Glandular Responses," describing instrumental conditioning of autonomic responses, was published in Science.
1973 — The Bulletin of the Psychonomic Society was first published, with Clifford T. Morgan as its editor.
1986 — The APA Council of Representatives voted to raise the dues of licensed professional psychologist members by $50 to support the costs of professional advocacy.