Comments on "Encoding and high-speed memory scanning..." by Maisto and Jerome.

Maisto and Jerome (1977) reported differences in reaction-time (RT) performance between retarded and nonretarded adolescents. They used the additive factor method, and their results showed differences in the speed of active memory scanning between the two populations; however, they violated a critical assumption underlying interpretation of the results, as there was nonindependence of the slope and intercept values of the function relating memory load to RT of retarded subjects. This departure from theoretically acceptable conditions makes the Maisto and Jerome data difficult to interpret.