Heart rate and visual evoked potentials during figuring arithmetic problems in boys acquired in early childhood with minimal brain damage

Changes of the pattern reversal EP and heart rate (HR) during calculating were studied on 32 boys with minimal brain damage and a control group (n 27) matched in age, sex and intelligence. The introduction of a reference period and repetition of the calculation period should improve the value of all results and should give simultaneously a first insight in the course of the parameters investigated, during mental loading. Both groups reached the same results in calculating, yet only the brain damaged boys simultaneously showed significant longer latencies of the EP. This result was interpreted as an effect of the higher loading of the damaged subjects. The task-depended increase of the HR was significant in both groups. The HR-level was getting lower with the increasing number of brain damage criteria. The results of intercorrelation between in physiologic parameters and datas of subjective feeling and results of calculating was negative in all cases. These findings were interpreted on the basis of several difficulties to find out clear cut patterns of reaction for different clinical groups.