Trait Anxiety Animals
Dr. Donaldson’s research is focused on understanding the intersect of biological (e.g, sex and personality traits) and environmental factors that create vulnerabilities and resilience to drug addiction. She uses a rodent model to explore biological sex and trait anxiety as pathways to drug addiction, such as how female and particularly anxious rodents are more sensitive to stimulant drugs, more likely to show impulsive behavior and relapse to drug-taking. She breeds her own trait anxiety animals at the University of Massachusetts vivarium to create high (HAn) and low anxiety (LAn) animals to explore the cellular and molecular factors that contribute to this stimulant drug vulnerability profile. She is also interested in the biology-environment interaction and using early interventions such as Closed Nestbox (CN) environments during pre-weaning, brief periodic maternal separation and enrichment strategies to reverse trait anxiety and drug vulnerable states.
Dr. Donaldson has demonstrated that her selectively-bred HAn animals show hyper-reactivity to anxiogenic stimuli, are more impulsive, more sensitive to the locomotor-activating effects of amphetamine and show higher corticosterone, blood pressure and core body temperature changes to mild stressors. After a minimum of 30 days in social and enriched environments, many of these behavioral and physiological differences can be ameliorated.
Working in collaboration with her Master’s student, Laura Grace Rollins, Dr. Donaldson is involved in a study that examines the impact of a Closed Nestbox ((CN), introduced during pre-weaning) on dam’s interaction with hypoxic ischemic (HI)-injured male and female pups. The rodent model of HI mimics many of the neurological and cognitive decline observed in term infants suffering from HI. We have found significantly positive impacts of CN on the neurological and cognitive impairment associated with this HI rodent mode. We are next exploring whether there is evidence for neural and molecular changes as well as morphological ‘resilience’ in pups from CN environments.