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Long-term potentiation (LTP)-like activity can be induced by stimulation protocols such as paired associative stimulation (PAS). We aimed to determine whether PAS-induced LTP-like activity (PAS-LTP) of the dorsolateral prefrontal cortex (DLPFC) is associated with cortical thickness and other structural measures impaired in Alzheimer's dementia (AD). We also explored longitudinal relationships between these brain structures and PAS-LTP response after a repetitive PAS (rPAS) intervention. Mediation and regression analyses were conducted using data from randomized controlled trials with AD and healthy control participants. PAS-electroencephalography assessed DLPFC PAS-LTP. DLPFC thickness and surface area were acquired from T1-weighted magnetic resonance imaging. Fractional anisotropy and mean diffusivity (MD) of the superior longitudinal fasciculus (SLF)—a tract important to induce PAS-LTP—were measured with diffusion-weighted imaging. AD participants exhibited reduced DLPFC thickness and increased SLF MD. There was also some evidence that reduction in DLPFC thickness mediates DLPFC PAS-LTP impairment. Longitudinal analyses showed preliminary evidence that SLF MD, and to a lesser extent DLPFC thickness, is associated with DLPFC PAS-LTP response to active rPAS. This study expands our understanding of the relationships between brain structural changes and neuroplasticity. It provides promising evidence for a structural predictor to improving neuroplasticity in AD with neurostimulation. This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Working memory is associated with gamma oscillations (30-50Hz). Previous studies have demonstrated altered gamma oscillations in the elderly population that may be related to general cognitive decline. However, it is unknown how gamma oscillations change with age or if there is an age when gamma oscillations optimally mediate working memory performance. That is, gamma oscillations may be maximal in middle-aged adults compared to younger and elderly adults. The objective of this study was to evaluate working memory evoked gamma oscillations in adults aged 19-29 years (mean 23.32±2.85 1SD) compared to adults aged 30-60 years (mean 39.10±8.11 1SD). METHODS: Subjects completed the verbal N-back task administered at four working loads (0, 1, 2, 3), while electroencephalography (EEG) was collected. Gamma power was measured during correct responses. RESULTS: Reduced gamma oscillations were observed in the adults aged 19-29 compared to those aged 30-60 years. Age was found to be positively related to the power of gamma oscillations. No differences were found on N-Back accuracy. CONCLUSIONS: Increased working memory evoked gamma oscillatory activity may provide a neurophysiological marker in the healthy aging brain. [ABSTRACT FROM AUTHOR]

Objective: Antipsychotic use in older patients is associated with many adverse effects, including tardive dyskinesia and extrapyramidal symptoms, which, in turn, increase the risk of falling. Antipsychotics are also associated with metabolic syndrome and cognitive impairment in older patients. Integrated care pathways (ICPs) are designed to manage specific conditions using standardized assessments and measurement-based interventions. This study aims to compare the use of recommended tools to monitor for adverse effects associated with antipsychotics in older patients managed within an ICP and those managed under usual care conditions-i.e., treatment as usual (TAU)., Methods: We reviewed and compared the health records of 100 older patients enrolled in an ICP for late-life schizophrenia with those of 100 older patients treated with antipsychotics under TAU conditions., Results: Monitoring rates were significantly higher in the ICP group than in the TAU group for all assessments: extrapyramidal symptoms (94% versus 5%), metabolic disturbances (91% versus 25%), fall risk (82% versus 35%), and cognitive impairment (72% versus 28%). Rates of antipsychotic polypharmacy were also six times higher in the TAU group., Conclusion: Older patients with schizophrenia treated with antipsychotics within an ICP experience higher rates of monitoring and less psychotropic polypharmacy than older patients treated with antipsychotics under TAU conditions. These findings suggest that an ICP can improve the quality of antipsychotic pharmacotherapy in older patients and thus possibly its effectiveness. This needs to be confirmed by a randomized controlled trial., (Copyright © 2018 Elsevier Ltd. All rights reserved.)