[Effects of lithium deficient diet on avoidance behavior].

To determine whether lithium deficiency has an effect on lever-press avoidance behavior, low lithium diets were given to mice and the effects of these diets on conditioned lever press avoidance response were compared with that of a commercial diet containing 110 ng Li/g diet. Three low-lithium diets were prepared in this experiment and the lithium contents of the diets were 6.6, 36.6 and 76.6 ng Li/g diet. The mice used in this experiment had been maintained on a practical diet and trained by Sidman's situation previously. After checking that the conditioned response was established, they were divided into four groups. Three groups of mice each were given one of the low lithium diets, indicated above, and these were assigned into the lithium-deficient groups. Some mice were given the practical diet and this group was used as controls. The avoidance behavior was analyzed by the method reported previously by the authors. After changing the diet to a low-lithium one, the avoidance behavior was significantly suppressed in lithium-deficient groups and this appeared to be proportional to the level of lithium deficiency in the diet. Furthermore, this suppression in the avoidance behavior was recovered by lithium supplementation in the same experimental diet. These findings suggest that low-lithium intake may suppress acquired avoidance behavior in mice.