Pictured in the Block Study archives are (l-r) developmental psychologists Avril Thorne, Per Gjerde, and David Harrington, surrounded by the voluminous amount of data collected since the study's inception in 1968. On the back cabinet is the "M&M machine," an ingenious tool used by researchers to measure children's impulsive behavior. After manipulating six candies through the mazelike contraption, the children were asked to decide if they wanted to eat the candy now or come back two days later for three times as many M&Ms.
(Photo: R.R. Jones)