INCREASED HIPPOCAMPAL ACETYLCHOLINE-RELEASE DURING A WORKING-MEMORY TASK

In this study we examined whether the food-reinforced alternation perf ormance was associated with increased acetylcholine output in the dors al hippocampus. Rats were trained to acquire the task using a T-maze. The control group consisted of rats introduced into the T-maze to run only on the day of dialysis. Acetylcholine release increased significa ntly in control rats only in the first 10 min after they were put into the T-maze. In trained rats acetylcholine output increased in the wai ting cage as well as during trials in the T-maze. The increase in acet ylcholine output in rats that had learned the task was significantly g reater than in control rats.