The effects of lithium on cognition: an updated review.
BACKGROUND
Adverse cognitive effects associated with lithium are often implicated as contributing to vocational and social impairment, as well as medication noncompliance. As impaired cognitive functioning caused by lithium has clear clinical implications, it is important to determine whether evidence for or against impaired cognitive functioning exists in the literature.


OBJECTIVE
An attempt is made to synthesize findings from previous studies, which assess a variety of cognitive domains, to determine whether conclusions can be drawn regarding lithium-associated cognitive impairment. The "reversibility" of neuropsychological impairment following lithium discontinuation and whether lithium administration has negative cumulative effects on cognition were also reviewed.


METHODS
Key word searches on "Medline" and "Psych Info" were completed for clinical articles that investigated the neuropsychological effects of lithium in clinical and normal populations between 1968 and 2000.


RESULTS
Despite methodological flaws, poor replicability and the subtle cognitive effects of lithium, five consistent findings emerged from the review; impairment on tasks of psychomotor speed, impaired functioning in the majority of studies examining verbal memory, no impairment on tasks of visuo-spatial constructional ability or attention/ concentration, and no negative cumulative effect.


CONCLUSIONS
Many patients administered lithium carbonate complained of mental slowness. Lithium carbonate also appeared to have definite, yet subtle, negative effects on psychomotor speed. Studies reviewed also showed a trend toward impaired verbal memory. Recommendations with respect to future research, methodological and statistical problems, and additional clinical implications are presented.
D000928:Antidepressive Agents / Q000009:adverse effects / Q000627:therapeutic use; D003072:Cognition Disorders / Q000139:chemically induced*; D003866:Depressive Disorder / Q000188:drug therapy*; D006801:Humans; D016651:Lithium Carbonate / Q000009:adverse effects / Q000627:therapeutic use; D008569:Memory Disorders / Q000139:chemically induced*; D011597:Psychomotor Performance / Q000187:drug effects
D000928:Antidepressive Agents; D016651:Lithium Carbonate