Cardiac Arrhythmias in Infant Pigtail Monkeys Following Maternal Separation

Abstract

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.

ATTACHMENT, LOSS, AND DEPRESSION*

“…While most infants (6 of 8) had their lowest mean night HR during nights Si to SA, in one infant (22.1), the lowest mean night HR was the 6th night, and in one (9.3), on the 10th night. We have also found the incidence of cardiac arrhythmias to increase following separation (Seiler et al, 1979), but since arrhythmias data was not obtained throughout separation in the infants described in this paper, we will not consider it further here.…”

Mother–infant cosleeping, breastfeeding and sudden infant death syndrome: What biological anthropology has discovered about normal infant sleep and pediatric sleep medicine

“…This is a noncontentious proposition for biological anthropologists, especially when considered in the context of nonhuman primate mother-infant separation studies which demonstrate that, due to the primate infants relative immaturity at birth and delayed maturity, even short-term separations between the mother and her offspring are known to have lasting, and potentially devastating, physiological consequences (see Reite and Field, 1985 for reviews). Pioneering research conducted on the underlying physiological aspects of attachment was begun by Harlow (1958Harlow ( , 1959; see also Blum, 2002) and further investigated amongst bonnet macaques, squirrel monkeys, pigtail monkeys (Seiler et al, 1979;Coe and Levine, 1981;Laudenslager et al, 1982;Coe et al, 1985;Reite et al, 1989). These researchers demonstrated exquisitely that short-term separations of infants from their mothers (for sleep or for other daytime periods) leads to an array of potentially life-threatening physiological changes such as adrenal-cortisol surges, immune dysfunction, and breathing abnormalities, while leaving infants alone to sleep induced serious impairments to sleep architecture, and amongst some infants cardiac arrhythmias, as well as a variety of depressive syndromes and immune deficiencies.…”

Behavioral determinants of severe cardiac inhibition

“…Studies by Reite (1977), , Reite, Short, Kaufman, Stynes, and Pauley (1978), and Seiler et al (1979) have demonstrated arrhythmias and CA apparently not caused by direct stimulation of young monkeys stressed by maternal separation. Yoked monkeys not allowed to predict or control electroshock exhibited severe bradycardia that led to ventricular arrests (Corley, Shiel, Path, Mauck, & Greenhoot, 1973;Corley et aI.…”

“…Delays shorter than the time unit cannot be determined in these conditions. On the other hand, arrhythmia has sometimes been defined as an alteration in or absence of rhythm of the heart (Seiler, Cullen, Zimmerman, and Reite, 1979) and can include a long delay between consecutive beats (arrest).…”

“…The experimental paradigms used by most of the authors are concerned with chronic stress, or its effects, and include conditioning, avoidance tasks, anticipation (Cohen, 1974b;Cohen & Obrist, 1975;Gantt, 1960), maternal separation (Seiler et al, 1979), and social status (Candland, Bryan, Nazar, Kopf, & Sendor, 1970). The physiological meaning of heart arrests concomitant with startle could be absolutely different from that of cardiovascular adaptations over a period of hours or days.…”