Beat‐by‐beat heart rate was observed during perceptual and cognitive performance in 78 kindergarten to third grade boys. Children at different Piagetian levels of perceptual and cognitive functioning were compared to see if changes in cardiac reactions mirrored different developmental levels of functioning.
The cardiac reactions appeared to be a joint function of attention and cognitive operations. Perceptual tasks produced deceleration in all subjects. In contrast, all cognitive tasks produced cardiac deceleration followed by acceleration. Larger amounts of cardiac acceleration were observed with higher levels of cognitive performance in conservation of length and in a verbal form of class inclusion, but not in class inclusion administered with pictures. Lower amounts of deceleration occurred with higher cognitive levels of performance only in conservation. Skin conductance reactions and rated motoric and motivational involvement were not related to cognitive level of performance.