Effects of Early Life Social Isolation on Cognitive Performance in Adult Rats
Poster #: 132
Session/Time: A
Author:
Frederique Emma Edjane Keumeni, BS
Mentor:
Larry D. Sanford, PhD
Research Type: Basic Science
Abstract
INTRODUCTION:
Social isolation (SI) and loneliness have adverse effects on health across the lifespan. In early life, the deleterious effects of SI and loneliness on development can persist and impact adulthood, whereas in older adults, they can increase the risk of cognitive decline, dementia, mental health disorders as well as chronic physiological diseases. There also are sex differences, with most evidence suggesting that females are more negatively impacted. In this study, we assessed how two levels of SI beginning at weaning impacted cognition in adulthood in male and female rats.
METHODS:
Male and female Wistar rats, at postnatal day 21, were assigned to one of three housing conditions: (SI; single housing), enhanced SI (ESI; single housing with opaque barriers between cages to prevent visual contact), or pair housing (PH; same-sex cage mate). Beginning at 11 weeks, cognitive performance was evaluated using three tasks (novel object recognition (NOR), Y-maze, and rat gambling task (rGT). In the NOR task, recognition memory was tested by evaluating the ability to distinguish between familiar and novel objects across two test days. In the Y-maze, spatial memory was tested by evaluating preference for a novel arm vs. familiar arms as measured by entries and exploration time. In the rGT, decision-making and response times were evaluated. Rats underwent at least two weeks of habituation with touchscreen training that became progressively more difficult. During testing, they could choose between safe low-reward options and riskier alternatives with higher potential rewards, allowing assessment of risk-taking strategies and sensitivity to outcomes.
RESULTS:
Full analysis is ongoing; however, preliminary findings from two of three behavioral tasks suggesting that SI beginning in early life can alter cognitive performance in Wistar rats in adulthood. Effects were greater in ESI rats and females performed more poorly on some tasks. In the rGT, ESI rats demonstrated altered decision making and differences in reward sensitivity compared to PH controls.
CONCLUSION:
Our preliminary results demonstrate that SI beginning in early life can adversely impact cognition in adulthood and suggest that greater degrees of isolation have greater negative effects. Females may also be more negatively impacted. As studies progress, this work will examine the effects SI and ESI at different ages and explore neuroimmune and neurocircuit mechanisms underlying their effects on cognition.
Social isolation (SI) and loneliness have adverse effects on health across the lifespan. In early life, the deleterious effects of SI and loneliness on development can persist and impact adulthood, whereas in older adults, they can increase the risk of cognitive decline, dementia, mental health disorders as well as chronic physiological diseases. There also are sex differences, with most evidence suggesting that females are more negatively impacted. In this study, we assessed how two levels of SI beginning at weaning impacted cognition in adulthood in male and female rats.
METHODS:
Male and female Wistar rats, at postnatal day 21, were assigned to one of three housing conditions: (SI; single housing), enhanced SI (ESI; single housing with opaque barriers between cages to prevent visual contact), or pair housing (PH; same-sex cage mate). Beginning at 11 weeks, cognitive performance was evaluated using three tasks (novel object recognition (NOR), Y-maze, and rat gambling task (rGT). In the NOR task, recognition memory was tested by evaluating the ability to distinguish between familiar and novel objects across two test days. In the Y-maze, spatial memory was tested by evaluating preference for a novel arm vs. familiar arms as measured by entries and exploration time. In the rGT, decision-making and response times were evaluated. Rats underwent at least two weeks of habituation with touchscreen training that became progressively more difficult. During testing, they could choose between safe low-reward options and riskier alternatives with higher potential rewards, allowing assessment of risk-taking strategies and sensitivity to outcomes.
RESULTS:
Full analysis is ongoing; however, preliminary findings from two of three behavioral tasks suggesting that SI beginning in early life can alter cognitive performance in Wistar rats in adulthood. Effects were greater in ESI rats and females performed more poorly on some tasks. In the rGT, ESI rats demonstrated altered decision making and differences in reward sensitivity compared to PH controls.
CONCLUSION:
Our preliminary results demonstrate that SI beginning in early life can adversely impact cognition in adulthood and suggest that greater degrees of isolation have greater negative effects. Females may also be more negatively impacted. As studies progress, this work will examine the effects SI and ESI at different ages and explore neuroimmune and neurocircuit mechanisms underlying their effects on cognition.