Electrodermal and Cardiovascular Responses in Nonreaders.

Autonomic response patterns of 20 male non-readers, ranging in age from 7 years 11 months to 11 years 4 months, were compared with those of 20 matched controls. Analyses were made of the onset orienting response, the offset orienting response and anticipatory response as measured for heart rate, finger pulse and electrodermal pheonomena (skin potential and skin resistance). Nonreaders had lower mean skin conductance levels across trials, greater amplitude of skin resistance response to a novel stimulus (75 decibel tone), fewer electrodermal offset responses, fewer negative and diphasic skin potential responses, fewer electrodermal and heart rate anticipatory responses, slower motor reaction times, and a higher degree of sinus arrhythmia. AII these differences between the groups were statistically significant. Habituation of the electrodermal, finger pulse, and heart rate onset responses did not differ, and no difference was found between groups as to the magnitude or shape of the heart rate onset response. Both groups showed decreasing skin conductance levels with increasing heart rate levels over trials. Data suggest nonreaders were physiologically less mature, unable to maintain a constant attentional level, and slower in "simple" learning than their matched controls. [ABSTRACT FROM AUTHOR]