The task is named for two notable experiments published in the 1950s in which it was first documented, the first by John Brown[1] and the second by husband-and-wife team Lloyd and Margaret Peterson.
The algebraic computations are administered between trigrams to assure the participant isn't using mnemonic strategies to chunk the letters into a single object.
Variants of the Brown–Peterson task are still used today, all with the same fundamental concept of administering items for the participant to remember while preventing the usage of additional cognitive resources to augment working memory.
[3] The Brown–Peterson task refers to two studies published in the late 1950s that used similar procedures; one in 1958 by John Brown[1] and a second in 1959 by Lloyd and Margaret Peterson.
After a set interval, a light signal was flashed to prompt the subject to cease verbally counting and to recall the random, three-letter nonsense syllable.
In addition, each nonsense syllable appeared an equal number of times; the trials were split evenly in terms of counting by either three or four.
In addition, the examiner and participant were instructed to enunciate in rhythm with a 120 BPM metronome, such that two letters or numbers were spoken per second.
The exact procedure from the first experiment was followed for 24 of the students, but the other 24 were asked to repeat the stimulus (i.e., the nonsense syllable) aloud until the examiner stated the three-digit number.
However, the analysis of the study concluded that forgetting was found to progress at differential rates dependent upon the amount of rehearsal that took place.