This chapter describes research that shows how mammalian infant vocalization is likely to have ev... more This chapter describes research that shows how mammalian infant vocalization is likely to have evolved as a component of the neuro-behavioral response of infants to separation from mother, littermates and home cage nest. The following questions are asked: how might evolution of the larynx as a protective valve during food and water ingestion and thermoregulatory physiology that was central to
After early maternal deprivation (on postnatal day 15), the incidence of restraint-induced gastri... more After early maternal deprivation (on postnatal day 15), the incidence of restraint-induced gastric erosions on day 30 increases to approximately 5 times that of rats separated at the customary (day 21) weaning age. These data suggest that factors in the mother-infant relationship during postnatal development in young rats can influence later susceptibility or resistance to gastric erosions. We present a series of experiments to test whether loss of behavioral interaction with the mother or loss of maternal milk results in this increase in gastric erosion susceptibility. The results show that the absence of maternal milk, rather than behavioral deprivation, is primarily responsible for the increase in susceptibility after early maternal separation. However, behavioral interaction with the mother can additionally modify this susceptibility.
A surgical procedure is described for the deafferentation of carotid sinus (CS) and aortic depres... more A surgical procedure is described for the deafferentation of carotid sinus (CS) and aortic depressor (AD) baroreceptors in 2-wk suckling rats. Baroreflex testing in unanesthetized pups showed that cardiac rate responses to acute elevations of blood pressure were reduced to less than 9% of controls after combined denervation (CSAD), 28% after AD and 47% after CS denervation at 4 h. After 24 h of nutrient deprivation, resting cardiac rates of sham operated controls fell a mean of -148 beat/min, significantly more than CS, AD, or CSAD groups (P less than 0.01). Baroreflex test responses in individuals correlated significantly with their later responses to nutrient deprivation (r = 0.67, P less than 0.01). There were no significant differences in base-line cardiac rate, systolic blood pressure, or cardiac rate during 24 h intragastric milk infusion between deafferented and control pups. These experiments suggest that arterial baroreceptors are important in the cardiovascular adjustments after nutrient deprivation in suckling rats.
Individual differences in maternal behavior in rodents are associated with altered physiology and... more Individual differences in maternal behavior in rodents are associated with altered physiology and behavior in offspring across their lifespan and across generations. Offspring of rat dams that engage in high frequencies of high-arched-back nursing and pup-licking (High-LG) show attenuated stress responses compared to those engaging in lower frequencies (Low-LG). Selective breeding also produces widespread alterations in physiology and behavior that are stable over generations. To examine processes underlying generational and developmental influences on anxiety in an animal model, we developed two lines of rats that emit either extremely high (High-USV) or low (Low-USV) rates of 45kHz ultrasonic vocalizations in isolation at postnatal day 10. Compared to the Low-USV line, High-USV rats display increased indices of anxiety- and depression-like behavior in adulthood. The current study assessed maternal behaviors as well as oxytocin and vasopressin receptor density in High-USV and Low-USV dams to determine if selective breeding had produced differences that paralleled those found in Low- and High-LG dams. We found that Low-USV dams engage in more high-arched nursing and pup-licking than High-USV dams. Differences in oxytocin and vasopressin receptor levels were not widespread throughout the brain, with line differences in the piriform cortex and nucleus accumbens. This research illustrates the potential interplay between genetically determined (USV line) and environmental (postnatal mother-infant interactions) factors in accounting for the phenotypes associated with maternal separation induced postnatal vocalizations.
... Handbook of attachment: Theory, research, and clinical applications. Polan, H. Jonathan; Hofe... more ... Handbook of attachment: Theory, research, and clinical applications. Polan, H. Jonathan; Hofer, Myron A. Cassidy, Jude (Ed); Shaver, Phillip R. (Ed), (1999). Handbook of attachment: Theory, research, and clinical applications, (pp. 162-180). ...
Building on the Legacy of T. Berry Brazelton, 2010
ABSTRACT This chapter contains sections titled: From Relationship to InteractionSeparation, Loss,... more ABSTRACT This chapter contains sections titled: From Relationship to InteractionSeparation, Loss, and the Regulation of DevelopmentSynchrony and ReciprocityMaternal Entrainment of Infant Sleep–Wake State OrganizationImplicationsReferences and further reading
Preterm infants are at high risk for adverse neurodevelopmental and behavioral outcomes. Family N... more Preterm infants are at high risk for adverse neurodevelopmental and behavioral outcomes. Family Nurture Intervention (FNI) in the Neonatal Intensive Care Unit (NICU) is designed to counteract adverse effects of separation of mothers and their preterm infants. Here, we evaluate effects of FNI on neurobehavioral outcomes. Data were collected at 18 months corrected age from preterm infants. Infants were assigned at birth to FNI or standard care (SC). Bayley Scales of Infant Development III (Bayley-III) were assessed for 76 infants (SC, n = 31; FNI, n = 45); the Child Behavior Checklist (CBCL) for 57 infants (SC, n = 31; FNI, n = 26); and the Modified Checklist for Autism in Toddlers (M-CHAT) was obtained for 59 infants (SC, n = 33; FNI, n = 26). Family Nurture Intervention significantly improved Bayley-III cognitive (p = .039) and language (p = .008) scores for infants whose scores were greater than 85. FNI infants had fewer attention problems on the CBCL (p < .02). FNI improved total M-CHAT scores (p < .02). Seventy-six percent of SC infants failed at least one of the M-CHAT items, compared to 27% of FNI infants (p < .001). In addition, 36% of SC infants versus 0% of FNI infants failed at least one social-relatedness M-CHAT item (p < .001). Family Nurture Intervention is the first NICU intervention to show significant improvements in preterm infants across multiple domains of neurodevelopment, social-relatedness, and attention problems. These gains suggest that an intervention that facilitates emotional interactions between mothers and infants in the NICU may be key to altering developmental trajectories of preterm infants.
This chapter describes research that shows how mammalian infant vocalization is likely to have ev... more This chapter describes research that shows how mammalian infant vocalization is likely to have evolved as a component of the neuro-behavioral response of infants to separation from mother, littermates and home cage nest. The following questions are asked: how might evolution of the larynx as a protective valve during food and water ingestion and thermoregulatory physiology that was central to
After early maternal deprivation (on postnatal day 15), the incidence of restraint-induced gastri... more After early maternal deprivation (on postnatal day 15), the incidence of restraint-induced gastric erosions on day 30 increases to approximately 5 times that of rats separated at the customary (day 21) weaning age. These data suggest that factors in the mother-infant relationship during postnatal development in young rats can influence later susceptibility or resistance to gastric erosions. We present a series of experiments to test whether loss of behavioral interaction with the mother or loss of maternal milk results in this increase in gastric erosion susceptibility. The results show that the absence of maternal milk, rather than behavioral deprivation, is primarily responsible for the increase in susceptibility after early maternal separation. However, behavioral interaction with the mother can additionally modify this susceptibility.
A surgical procedure is described for the deafferentation of carotid sinus (CS) and aortic depres... more A surgical procedure is described for the deafferentation of carotid sinus (CS) and aortic depressor (AD) baroreceptors in 2-wk suckling rats. Baroreflex testing in unanesthetized pups showed that cardiac rate responses to acute elevations of blood pressure were reduced to less than 9% of controls after combined denervation (CSAD), 28% after AD and 47% after CS denervation at 4 h. After 24 h of nutrient deprivation, resting cardiac rates of sham operated controls fell a mean of -148 beat/min, significantly more than CS, AD, or CSAD groups (P less than 0.01). Baroreflex test responses in individuals correlated significantly with their later responses to nutrient deprivation (r = 0.67, P less than 0.01). There were no significant differences in base-line cardiac rate, systolic blood pressure, or cardiac rate during 24 h intragastric milk infusion between deafferented and control pups. These experiments suggest that arterial baroreceptors are important in the cardiovascular adjustments after nutrient deprivation in suckling rats.
Individual differences in maternal behavior in rodents are associated with altered physiology and... more Individual differences in maternal behavior in rodents are associated with altered physiology and behavior in offspring across their lifespan and across generations. Offspring of rat dams that engage in high frequencies of high-arched-back nursing and pup-licking (High-LG) show attenuated stress responses compared to those engaging in lower frequencies (Low-LG). Selective breeding also produces widespread alterations in physiology and behavior that are stable over generations. To examine processes underlying generational and developmental influences on anxiety in an animal model, we developed two lines of rats that emit either extremely high (High-USV) or low (Low-USV) rates of 45kHz ultrasonic vocalizations in isolation at postnatal day 10. Compared to the Low-USV line, High-USV rats display increased indices of anxiety- and depression-like behavior in adulthood. The current study assessed maternal behaviors as well as oxytocin and vasopressin receptor density in High-USV and Low-USV dams to determine if selective breeding had produced differences that paralleled those found in Low- and High-LG dams. We found that Low-USV dams engage in more high-arched nursing and pup-licking than High-USV dams. Differences in oxytocin and vasopressin receptor levels were not widespread throughout the brain, with line differences in the piriform cortex and nucleus accumbens. This research illustrates the potential interplay between genetically determined (USV line) and environmental (postnatal mother-infant interactions) factors in accounting for the phenotypes associated with maternal separation induced postnatal vocalizations.
... Handbook of attachment: Theory, research, and clinical applications. Polan, H. Jonathan; Hofe... more ... Handbook of attachment: Theory, research, and clinical applications. Polan, H. Jonathan; Hofer, Myron A. Cassidy, Jude (Ed); Shaver, Phillip R. (Ed), (1999). Handbook of attachment: Theory, research, and clinical applications, (pp. 162-180). ...
Building on the Legacy of T. Berry Brazelton, 2010
ABSTRACT This chapter contains sections titled: From Relationship to InteractionSeparation, Loss,... more ABSTRACT This chapter contains sections titled: From Relationship to InteractionSeparation, Loss, and the Regulation of DevelopmentSynchrony and ReciprocityMaternal Entrainment of Infant Sleep–Wake State OrganizationImplicationsReferences and further reading
Preterm infants are at high risk for adverse neurodevelopmental and behavioral outcomes. Family N... more Preterm infants are at high risk for adverse neurodevelopmental and behavioral outcomes. Family Nurture Intervention (FNI) in the Neonatal Intensive Care Unit (NICU) is designed to counteract adverse effects of separation of mothers and their preterm infants. Here, we evaluate effects of FNI on neurobehavioral outcomes. Data were collected at 18 months corrected age from preterm infants. Infants were assigned at birth to FNI or standard care (SC). Bayley Scales of Infant Development III (Bayley-III) were assessed for 76 infants (SC, n = 31; FNI, n = 45); the Child Behavior Checklist (CBCL) for 57 infants (SC, n = 31; FNI, n = 26); and the Modified Checklist for Autism in Toddlers (M-CHAT) was obtained for 59 infants (SC, n = 33; FNI, n = 26). Family Nurture Intervention significantly improved Bayley-III cognitive (p = .039) and language (p = .008) scores for infants whose scores were greater than 85. FNI infants had fewer attention problems on the CBCL (p < .02). FNI improved total M-CHAT scores (p < .02). Seventy-six percent of SC infants failed at least one of the M-CHAT items, compared to 27% of FNI infants (p < .001). In addition, 36% of SC infants versus 0% of FNI infants failed at least one social-relatedness M-CHAT item (p < .001). Family Nurture Intervention is the first NICU intervention to show significant improvements in preterm infants across multiple domains of neurodevelopment, social-relatedness, and attention problems. These gains suggest that an intervention that facilitates emotional interactions between mothers and infants in the NICU may be key to altering developmental trajectories of preterm infants.
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