Mental Mechanisms in Performing Elementary Numerical Operations

Abstract

21 college students served as Ss in an experiment concerned with speed of adding simple numbers. The results partially confirmed the hypothesis of Groen (1967) and Restle (1970) of a mental analog mechanism in which speed of adding two numbers is a linear function of the smaller number but independent of the larger number. However, in contrast to that hypothesis, the results indicate that speed of addition is a linear function of both the larger and smaller numbers in a problem. Finally, significant departures from this general finding were also noted, indicating that on certain well-learned problems the answer may be obtained by simple memory search or associations rather than by an analog computational process.