San Francisco Brain Research Institute & SAM Technology, San Francisco, CA 94131, United States.
Clin Neurophysiol. 2012 Jul;123(7):1291-9. doi: 10.1016/j.clinph.2011.11.004. Epub 2011 Dec 11.
Assess individual-subject long-term and within-day variability of a combined behavioral and EEG test of working memory.
EEGs were recorded from 16 adults performing n-back working memory tasks, with 10 tested in morning and afternoon sessions over several years. Participants were also tested after ingesting non-prescription medications or recreational substances. Performance and EEG measures were analyzed to derive an Overall score and three constituent sub-scores characterizing changes in performance, cortical activation, and alertness from each individual's baseline. Long-term and within-day variability were determined for each score; medication effects were assessed by reference to each individual's normal day-to-day variability.
Over the several year period, the mean Overall score and sub-scores were approximately zero with standard deviations less than one. Overall scores were lower and their variability higher in afternoon relative to morning sessions. At the group level, alcohol, diphenhydramine and marijuana produced significant effects, but there were large individual differences.
Objective working memory measures incorporating performance and EEG are stable over time and sensitive at the level of individual subjects to interventions that affect neurocognitive function.
With further research these measures may be suitable for use in individualized medical care by providing a sensitive assessment of incipient illness and response to treatment.
评估工作记忆的组合行为和脑电图测试的个体长期和日内变异性。
对 16 名成年人进行 EEG 记录，他们执行 n-back 工作记忆任务，其中 10 名在多年的早晨和下午时段进行测试。参与者还在服用非处方药物或娱乐性物质后接受了测试。对绩效和 EEG 指标进行分析，得出一个综合评分和三个组成评分，用于描述从每个人的基线变化的绩效、皮层激活和警觉性。确定每个分数的长期和日内变异性；通过参考每个人的日常变异性来评估药物的影响。
在几年的时间里，平均总分和子分数都接近零，标准差小于一。与早晨相比，下午的总体得分较低，其变异性较高。在组水平上，酒精、苯海拉明和大麻产生了显著的影响，但个体差异很大。
纳入绩效和脑电图的客观工作记忆测量在时间上是稳定的，并且在个体水平上对影响神经认知功能的干预措施敏感。
随着进一步的研究，这些措施可能适合在个体化医疗中使用，通过对疾病初期和治疗反应的敏感评估。
