Open AccessMaternal neglect and the serotonin system are associated with daytime sleep in infant rhesus monkeys
Author(s) -
Alexander Baxter,
Elizabeth K. Wood,
Christina S. Barr,
Daniel Kay,
Stephen J. Suomi,
J. Dee Higley
Publication year - 2019
Publication title -
development and psychopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.761
H-Index - 171
eISSN - 1469-2198
pISSN - 0954-5794
DOI - 10.1017/s0954579418001359
Subject(s) - serotonin transporter , serotonin , psychology , sleep (system call) , serotonin plasma membrane transport proteins , neglect , sleep deprivation , genotype , medicine , endocrinology , physiology , circadian rhythm , psychiatry , neuroscience , biology , biochemistry , receptor , computer science , gene , operating system
Environmental and biological factors contribute to sleep development during infancy. Parenting plays a particularly important role in modulating infant sleep, potentially via the serotonin system, which is itself involved in regulating infant sleep. We hypothesized that maternal neglect and serotonin system dysregulation would be associated with daytime sleep in infant rhesus monkeys. Subjects were nursery-reared infant rhesus macaques (n = 287). During the first month of life, daytime sleep-wake states were rated bihourly (0800-2100). Infants were considered neglected (n = 16) if before nursery-rearing, their mother repeatedly failed to retrieve them. Serotonin transporter genotype and concentrations of cerebrospinal fluid 5-hydroxyindoleacetic acid (5-HIAA) were used as markers of central serotonin system functioning. t tests showed that neglected infants were observed sleeping less frequently, weighed less, and had higher 5-HIAA than non-neglected nursery-reared infants. Regression revealed that serotonin transporter genotype moderated the relationship between 5-HIAA and daytime sleep: in subjects possessing the Ls genotype, there was a positive correlation between 5-HIAA and daytime sleep, whereas in subjects possessing the LL genotype there was no association. These results highlight the pivotal roles that parents and the serotonin system play in sleep development. Daytime sleep alterations observed in neglected infants may partially derive from serotonin system dysregulation.