Influence of Rhythmic Sensory Stimuli Upon the Heart-Rate

Eighteen retarded adults, divided into three groups equated for IQ, MA, and number conservation performance, received addition-subtraction and reversibility training under either cognitive-conflict or nonconflict conditions, or received no training. Under cognitive-conflict, transformation of one of two sets of discrete elements produced a perceptual illusion, and the addition-subtraction and reversibility operations applied to that set produced conflict between its length and density. Under nonconflict, simultaneous application of the operations to both sets avoided such conflict. Both training groups made significant gains from pretest and significantly exceeded controls in posttest number conservation (ps < .05). Lack of differential gains by the training groups suggested that cognitive conflict is not essential to induce number conservation.