CARDIAC-ARRHYTHMIAS IN INFANT PIGTAIL MONKEYS FOLLOWING MATERNAL SEPARATION

The occurrence of nocturnal cardiac arrhythmias was determined in 9 infant pigtail (M. nemestrina) monkeys during 3 baseline normal nights, 3 nights following maternal separation, and 3 nights following reunion with the mother. All infants lived in social groups where they had been raised by their natural mothers; heart rate data were collected by means of totally implantable biotelemetry systems. Marked individual differences were found in the mean frequency of cardiac arrhythmias in the baseline condition, and infants with lower heart rates had a greater mean number of arrhythmias. Maternal separation was accompanied by both increases in arrhythmias and decreases in heart rate. The relationship (slope of the regression line) between arrhythmias and heart rate changed in 8 of the 9 infants during separation, suggesting that the increase in arrhythmias was greater than could be accounted for by the decreases in heart rate alone. While both heart rate and arrhythmia values tended to return to baseline values following reunion with the mother, some infants exhibited prolonged separation‐induced alterations. Copyright © 1979, Wiley Blackwell. All rights reserved