Broadbent came up with this theory based on data from an experiment: three pairs of different digits are presented simultaneously, one set of three digits in one ear, and another set of three digits in the other.
Broadbent pakkus selle teooria välja katseandmetele tuginedes: kolmest erinevast numbrist koosnevat paari esitatakse samaaegselt, üks komplekt kolmest numbrist ühte kõrva ja teine teise kõrva.