Effect of noise distractibility on the spans of apprehension of hyperactive boys.

Denton and McIntyre (1978), using a forced-choice letter-recognition procedure, demonstrated increasing reductions in the spans of apprehension of hyperactive as compared to normal boys when a signal letter was embedded within an increasing number of noise letters. In the present study, the effect of variations in the amount of physical signal-noise similarity and noise redundancy upon the spans of apprehension of hyperactive and normal boys was compared to determine whether noise letters act as more potent distractors for the hyperactive boys. Results indicated the spans of both groups were effected equivalently by variations in signal-noise similarity and noise redundancy. No evidence for a distractibility explanation was obtained.