Post-training self administration of sugar facilitates cognitive performance of male C57BL/6J mice in two spatial learning tasks

Publication Type:

Journal Article

Source:

Behav Brain Res, Volume 198, Number 1, p.98-104 (2009)

DOI Name (links to online publication)

10.1016/j.bbr.2008.10.016

Keywords:

Animal; ANIMAL MODEL; ANIMAL MODELS; ANIMAL-MODEL; ANIMAL-MODELS; C57BL/6J; Corticosterone; Disease; Diseases; HORMONE; Learning; Male; Memory; Mice; MODEL; MODULATION; Netherlands; PERFORMANCE; pharmacology; Research; Reward; Self Administration; SPATIAL

Abstract:

Spatial memory can be strengthened by adverse stimuli that activate the stress system, and administration of the stress hormone corticosterone in close-context with the learning task. Less is known about modulation of spatial memory by post-training positive reinforcers (reward). Cognitive performance was assessed in male C57BL/6J mice using two learning tasks: the water maze (WM) and circular hole board (CHB). Sugar was chosen as a post-training reinforcer. We expected that the free access to sugar immediately (0h) after training would facilitate spatial memory; delayed access to sugar (4h after training) or no sugar served as controls. In both tasks, 0h sugar mice showed superior performance, indicated by shorter latencies and distances to the trained spatial location. The memory facilitating effect of sugar became visible at distinct times during training: on the CHB from the first trial onwards, in the WM on training days 4 and 5. Sugar-rewarded mice kept their superior performance during the free exploration/swim trial, expressed by more persistent search strategies for the exit hole or platform. Post-training sugar reward in close-context with performance strengthens memory via modulation of consolidation. This finding supports the integrative theory of reinforcement and memory. We suggest that our experimental set-up will allow to differentiate between direct effects on memory and alterations in reward processes in animal models of stress-related diseases

18/01/2013