Department of Family Medicine, Vrije Universiteit Brussel, Belgium.
Psychol Res Behav Manag. 2013 Aug 27;6:65-74. doi: 10.2147/PRBM.S47526. eCollection 2013.
Increasing numbers of students use stimulants such as methylphenidate (MPH) to improve their study capacity, making them prone to subsequent prolonged drug abuse. This study explored the cognitive effects of MPH in students who either assumed they received MPH or assumed they received a placebo.
In a double-blind, randomized, placebo-controlled trial with a between-subjects design, 21 students were subjected to partial sleep deprivation, receiving no more than 4 hours sleep the night before they were tested. In the morning, they were given either a placebo or 20 mg of MPH. They then performed free recall verbal tests and Go/No-Go tasks repeatedly, their moods were evaluated using Profile of Mood States and their tiredness was assessed using a visual analog scale, with evaluation of vigilance.
No significant differences were found between those subjects who received MPH and those who received a placebo. However, significant differences were found between subjects who assumed they had received MPH or had no opinion, and those who assumed they had received a placebo. At three minutes, one hour, and one day after memorizing ten lists of 20 words, those who assumed they had received MPH recalled 54%, 58%, and 54% of the words, respectively, whereas those who assumed they had received placebo only recalled 35%, 37%, and 34%.
Healthy, partially sleep-deprived young students who assume they have received 20 mg of MPH experience a substantial placebo effect that improves consolidation of information into long-term memory. This is independent of any pharmacologic effects of MPH, which had no significant effects on verbal memory in this study. This information may be used to dissuade students from taking stimulants such as MPH during examination periods, thus avoiding subsequent abuse and addiction.
越来越多的学生使用兴奋剂，如哌醋甲酯（MPH）来提高他们的学习能力，使他们容易随后长期滥用药物。本研究探讨了 MPH 对假定接受 MPH 或假定接受安慰剂的学生的认知影响。
在一项双盲、随机、安慰剂对照、组间设计的试验中，21 名学生接受部分睡眠剥夺，在测试前一晚睡眠时间不超过 4 小时。早上，他们要么接受安慰剂，要么接受 20 毫克 MPH。然后，他们反复进行自由回忆口头测试和 Go/No-Go 任务，使用心境状态问卷评估他们的情绪，使用视觉模拟量表评估他们的疲劳程度，并评估警觉性。
接受 MPH 和接受安慰剂的受试者之间没有发现显著差异。然而，假定接受 MPH 或没有意见的受试者与假定接受安慰剂的受试者之间存在显著差异。在记忆十组 20 个单词的三分钟、一小时和一天后，假定接受 MPH 的受试者分别回忆起 54%、58%和 54%的单词，而假定接受安慰剂的受试者仅回忆起 35%、37%和 34%的单词。
健康、部分睡眠剥夺的年轻学生，如果假定他们服用了 20 毫克 MPH，会产生显著的安慰剂效应，从而改善信息的巩固，进入长期记忆。这与 MPH 的任何药理作用无关，在这项研究中，MPH 对口头记忆没有显著影响。这些信息可以用来劝阻学生在考试期间服用兴奋剂，如 MPH，从而避免随后的滥用和成瘾。
