Effects of chronic social - defeat stress on impulsive decision making in mice.
Bakker-CA; Kieres-AK; Peterson-VA; Farrar-AM; Hausknecht-KA; Acheson-A; Choi-S; Miller-DB; Reynolds-B; Miczek-KA; Richards-JB
Program No. 236.4. 2004 Abstract Viewer/Itinerary Planner. Washington, DC: Society for Neuroscience, 2004 Oct; :1
Delay discounting is a fundamental behavioral process that may underlie impulsive behavior in both humans and non-humans. Delay discounting refers to decreases in the subjective value of a reward when it is delayed. Impulsive individuals discount the value of delayed rewards more rapidly, reflecting poor control over behavior by delayed consequences. Here we examined the effects of chronic social-defeat stresson delay discounting. AMP has been shown to decrease impulsivity in rats, and animals exposed to chronic social defeat stress exhibit cross-sensitization to the locomotor effects of AMP. In this study we examined the effects of chronic social stresson discounting of delayed rewards and to the locomotor effects of AMP in male C57BL/6 mice. An adjusting amount procedure was used to determine discounting of delayed water rewards (1 Oml delayed by 0, 1, 2, 4 & 8 s). Sixteen mice underwent 10 weeks of chronic social-defeat stress, while being tested on delay discounting daily. A control group (n=16) was tested on delay discounting but not stressed. After completion of the chronic stress regimen mice were tested for locomotor responses to AMP. Compared to controls, the urine of stressed mice had elevated corticosterone. Chronic social defeat stresshad no effect on discounting of delayed rewards, although it did increase the time it took the animals to choose between the immediate and delayed rewards and decreased the number of trials completed. In contrast, chronic stress exhibited greater motor activation after AMP. These results indicate that chronic stressincreases AMP sensitization without increasing impulsive behavior.
Laboratory-animals; Animal-studies; Animals; Decision-making; Behavior-patterns; Psychological-effects; Psychological-stress; Central-nervous-system; Brain-function; Endocrine-function
Abstract; Conference/Symposia Proceedings
Program No. 236.4. 2004 Abstract Viewer/Itinerary Planner