HIV Infection results in many patients in neurocognitive disorders which impair daily life starting with mild disturbances to a full-blown dementia. Some of these symptoms can be managed with antiretroviral therapy but others remain and reduce quality of life of these patients. Two pilot studies suggested that lithium have a positive impact on the symptoms of HIV-associated neurocognitive impairment. In this research project we will address the efficacy of lithium in a larger, placebo-controlled study. A total of 108 patients will be treated for 24 weeks with lithium or placebo as adjunctive therapy to antiretroviral treatment and the effects on neurocognition will be determined. Within this EDCTP project, mechanistic aspects of lithium therapy in HIV patients will be investigated in Würzburg (PI E. Koutsilieri) to understand its basic mode of action whereas changes in the regulation of dopaminergic pathways is on the centre of investigation.