NEUROPSYCHOLOGIC EFFECTS OF LITHIUM DISCONTINUATION

This study investigated the effects of blind lithium discontinuation a nd resumption on measures of cognition, creativity, and fine motor per formance in 46 lithium-maintained euthymic outpatients. Scores on memo ry measures, tests of tapping speed, and associative productivity all improved significantly during the time off of lithium. In an effort to further explain these results, analyses were undertaken with six poss ible intervening variables: age, sex, lithium concentration in plasma, thyroid function, duration of lithium maintenance, and depressive sym ptoms. Significant group and interactive effects are reported and disc ussed. A multiple regression analysis suggested that lithium has a gre ater neuropsychologic effect in younger, less-depressed patients havin g higher lithium concentrations in plasma.