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While several studies have found that neural oscillations play a key role in the functioning of working memory, the nature of aberrant oscillatory activity underlying working memory impairments in Alzheimer's disease (AD) and mild cognitive impairment (MCI) remains largely unexplored. These individuals often display structural alterations in brain regions and pathways involved in working memory processes and therefore may also display altered oscillatory activity during memory activation. Electroencephalographic (EEG) activity was recorded during the N-back working memory task in three groups: AD (n = 29), MCI (n = 100), and healthy controls (HCs; n = 40). Theta (4-7 Hz) and alpha (7.5-12 Hz) modulation was measured in response to the stimulus presentation during correct and incorrect responses. This modulation represents the change in EEG activity associated with the stimulus onset and was measured as a ratio of post stimulus power to pre stimulus power. We also assessed the relationship between change in oscillatory power and working memory performance. Compared to HCs, the AD group demonstrated the lowest working memory accuracy and a smaller theta ratio for correct responses on the 2-back condition; the MCI group demonstrated a smaller theta ratio for correct responses on the 3-back condition. Finally, we observed that the theta ratio, but not the alpha ratio, was a significant predictor of working memory performance in the three groups for all conditions. Taken together, these behavioral and electrophysiological results suggest that in addition to impairments in working memory performance, modulation of theta, but not alpha power, may be impaired in MCI and AD. [ABSTRACT FROM AUTHOR]

The S allele of the serotonin transporter promoter polymorphism (5-HTTLPR) has been associated with increased vulnerability to depressive symptoms and increased amygdala responsiveness to emotional stimuli. The goal of the [...]

Automated machine learning (AML) may provide a means of approaching hierarchical mixed effects modelling that permits a greater number of models to be assessed in the context of covariate selection, [...]

Late-life depression is a serious health problem that is challenging to manage but generally responds well to pharmacotherapy. Selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors (SSRIs), the most commonly prescribed antidepressants, are usually used as first-line agents for elderly patients with depression. Like most drugs, SSRIs have not been widely tested in clinical trials that approximate ‘real-life’ geriatric situations. However, studies completed to date provide valuable information about the efficacy, safety and tolerability of this class of antidepressants among older patients with depression, including those with depression secondary to stroke or dementia and those with other comorbid physical disorders. Although one SSRI may be more efficacious or better tolerated by elderly patients than another, existing data do not support such claims. However, other distinguishing features may influence the choice of agent. For example, fluoxetine, fluvoxamine and paroxetine are more likely to be involved in significant drug-drug interactions than are citalopram or sertraline. In contrast to the other SSRIs, fluoxetine has a half-life well in excess of 1 day, which can be an advantage when weaning the patient off therapy in that it may reduce the incidence of discontinuation symptoms, but a significant disadvantage if the patient cannot tolerate the drug or experiences an adverse drug-drug interaction. [ABSTRACT FROM AUTHOR]

The atypical antipsychotics are a new class of agents with great promise for use in the elderly because of their reduced propensity to cause acute extrapyramidal adverse effects. Treatment of older patients with these agents, however, needs to take into consideration age-related changes in pharmacokinetics and the risks of drug-drug interactions. Additionally, current evidence of their efficacy in late-life psychoses is derived largely from case series and from the extrapolation of results obtained in studies of younger patients with schizophrenia. Controlled clinical studies of atypical antipsychotics in elderly patients are urgently needed. [ABSTRACT FROM AUTHOR]