15 research outputs found
Rumination in bipolar disorder: evidence for an unquiet mind
Depression in bipolar disorder has long been thought to be a state characterized by mental inactivity. However, recent research demonstrates that patients with bipolar disorder engage in rumination, a form of self-focused repetitive cognitive activity, in depressed as well as in manic states. While rumination has long been associated with depressed states in major depressive disorder, the finding that patients with bipolar disorder ruminate in manic states is unique to bipolar disorder and challenges explanations put forward for why people ruminate. We review the research on rumination in bipolar disorder and propose that rumination in bipolar disorder, in both manic and depressed states, reflects executive dysfunction. We also review the neurobiology of bipolar disorder and recent neuroimaging studies of rumination, which is consistent with our hypothesis that the tendency to ruminate reflects executive dysfunction in bipolar disorder. Finally, we relate the neurobiology of rumination to the neurobiology of emotion regulation, which is disrupted in bipolar disorder
Structural, Metabolic, and Functional Brain Abnormalities as a Result of Prenatal Exposure to Drugs of Abuse: Evidence from Neuroimaging
Prenatal exposure to alcohol and stimulants negatively affects the developing trajectory of the central nervous system in many ways. Recent advances in neuroimaging methods have allowed researchers to study the structural, metabolic, and functional abnormalities resulting from prenatal exposure to drugs of abuse in living human subjects. Here we review the neuroimaging literature of prenatal exposure to alcohol, cocaine, and methamphetamine. Neuroimaging studies of prenatal alcohol exposure have reported differences in the structure and metabolism of many brain systems, including in frontal, parietal, and temporal regions, in the cerebellum and basal ganglia, as well as in the white matter tracts that connect these brain regions. Functional imaging studies have identified significant differences in brain activation related to various cognitive domains as a result of prenatal alcohol exposure. The published literature of prenatal exposure to cocaine and methamphetamine is much smaller, but evidence is beginning to emerge suggesting that exposure to stimulant drugs in utero may be particularly toxic to dopamine-rich basal ganglia regions. Although the interpretation of such findings is somewhat limited by the problem of polysubstance abuse and by the difficulty of obtaining precise exposure histories in retrospective studies, such investigations provide important insights into the effects of drugs of abuse on the structure, function, and metabolism of the developing human brain. These insights may ultimately help clinicians develop better diagnostic tools and devise appropriate therapeutic interventions to improve the condition of children with prenatal exposure to drugs of abuse
Identifying the preferred RNA motifs and chemotypes that interact by probing millions of combinations
Neurobiologia do transtorno de humor bipolar e tomada de decisĂŁo na abordagem psicofarmacolĂłgica
O Transtorno do Humor Bipolar (THB) caracteriza-se por oscilações do humor que causam prejuĂzos significativos no âmbito biopsicossocial. O interesse da comunidade cientĂfica por este transtorno vem aumentando nos Ăşltimos cinco anos em função de sua crescente prevalĂŞncia associada ao refinamento diagnĂłstico, Ă ampliação do arsenal terapĂŞutico e ao conhecimento dos avanços nas pesquisas da neurobiologia do transtorno. A presente revisĂŁo aborda questões diagnosticas e terapĂŞuticas aplicadas Ă neurobiologia dos THB, relacionando-as diretamente Ă terapĂŞutica dos quadros de mania, hipomania, estados mistos, depressĂŁo bipolar e ciclagem rápida, da infância Ă idade adulta. SĂŁo revisados criticamente importantes estudos realizados com diferentes fármacos potencialmente eficazes como estabilizadores do humor, nos diversos subdiagnĂłsticos do THB. SĂŁo analisados fármacos, tais como o lĂtio, anticonvulsivantes, antipsicĂłticos, benzodiazepĂnicos, bloqueadores dos canais de cálcio e hormĂ´nio tireoideo, bem como as possĂveis bases biolĂłgicas para seus efeitos terapĂŞuticos. Em sĂntese, este trabalho aborda os avanços da psicofarmacologia cuja eficácia Ă© comprovada nos subtipos do THB, procurando relacioná-los com a neurobiologia deste transtorno.Bipolar Disorder (BD) is characterized by mood swings that cause significant impairment in social, occupational, or other areas of functioning. During the last years, new insights have been provided in the diagnosis, etiology, neurobiological basis and treatment of bipolar disorder. This paper emphasizes recent studies related to some diagnostic and therapeutic aspects during manic episode, hypomanic, mixed episode, bipolar depression and rapid cycling, in children, adolescents and adults. Studies using proposed mood stabilizers, which present adequate metodological basis, including double–blind, controlled studies and which presented a significant number of patients were included and critically evaluated in this revision. Drugs such as the lithium, anticonvulsants, antipsychotics, benzodiazepines, calcium channels blockers and thyroid augmentation are proposed to be effective in certain diagnostic profiles. The possible biological bases for these drugs therapeutic effects are also revised. In summary, this article focuses on recent and important psychopharmacological progresses on the treatment of BD subtypes. Furthermore, the revision presents possible biological basis to explain the therapeutic profile of these drugs
Brain microglia in psychiatric disorders
Summary The role of immune activation in psychiatric disorders has attracted considerable attention over the past two decades, contributing to the rise of a new era for psychiatry. Microglia, the macrophages of the brain, are progressively becoming the main focus of the research in this field. In this Review, we assess the literature on microglia activation across different psychiatric disorders, including post-mortem and in-vivo studies in humans and experimental studies in animals. Although microglia activation has been noted in all types of psychiatric disorder, no association was seen with specific diagnostic categories. Furthermore, the findings from these studies highlight that not all psychiatric patients have microglial activation. Therefore, the cause of the neuroinflammation in these cohorts and its implications are unclear. We discuss psychosocial stress as one of the main factors determining microglial activation in patients with psychiatric disorders, and explore the relevance of these findings for future treatment strategies