Barr Developmental Psychobiology Laboratory
The Barr Lab focuses on the role of the environment in normal development. Clinically, one important stressor for hospitalized human infants is pain, but when starting this work, little was known of how it was processed in the infant.
The lab and others focused initially on the spinal cord which matures early, but found that pain activates the brain later and includes “affective” sites. The lab also found defined changes in how analgesic drugs work during development. These findings have important implications for understanding the long-term effects of pain neural circuits that depend on when injury occurs.
Human infants treated with opiates for pain relief when they are hospitalized can develop tolerance and dependence. Little was known about if and how this syndrome differed in infants and indeed, there were animal studies arguing that infant animal models did not show withdrawal to morphine. The lab published 40+ opioid-related papers describing how opioid analgesia differed in both receptor pharmacology and neural localizations and how morphine tolerance and dependence change during infancy, defining both commonalities and differences.
In other studies of the neural substrates of early life stress, the lab found that the prefrontal cortex (PFC) is initially unresponsive to a threat prior to weaning, becomes responsive as juveniles, but does not regulate the response at that age, which first occurs during pre-adolescence, demonstrating age-related dissociation of PFC’s receipt of information about a threat and its ability to act on it.
With Regina Sullivan, PhD, of New York University, the lab studied the transition from immature to adult-like responses to “trauma” in the context of attachment to the mother. The lab found that a major factor in the switch from attachment to aversion is the switch in dopamine function in the amygdala and this early life stress can change adult outcomes.
- The Barr Lab was the first to demonstrate opioid withdrawal behaviors working with infant animal models that are characterized by increased ultrasonic vocalizations and was one of two groups to characterize a behavioral opioid withdrawal syndrome working with an infant animal model.
- In studies of unlearned fear, the lab found that the prefrontal cortex is initially unresponsive to a threat (e.g. prior to weaning), becomes responsive to the threat as juveniles, but does not regulate the response at that age, which first occurs during pre-adolescence.
- Pain in infants, mimicking clinical pain, activates brain neural circuitry that matures slowly in the first two weeks of an animal model’s life to include “affective” sites, in contrast to the early maturation of spinal cord pain circuits.
- Medically essential early life pain for critically ill infants is often experienced on the background of infection. The lab has shown that concomitant infection, alongside pain treatment with chronic opioids, altered dependence on opioids in an age specific manner but worsens outcomes in adults compared to either pain or infection alone.
- The lab discovered that the major factor in the switch from attachment to aversion in infants following a noxious stimulus is the activation of dopamine function in the amygdala.
James Battaglia Endowed Chair in Pediatric Pain Management
Dr. Barr's research focuses on transitions as important developmental epochs during which there are substantial changes in how infants/children/adolescents process information. He studies mechanisms of stress, pain, and recovery from damage to the nervous system from a developmental perspective.