Department of Psychology, Clemson University, Clemson, SC, USA.
Brain Res. 2012 Nov 5;1483:54-62. doi: 10.1016/j.brainres.2012.09.015. Epub 2012 Sep 14.
The current study examines the effect of administering dehydroepiandrosterone (DHEA) on short-term memory. This experiment used a double-blind placebo-controlled cross-over design to explore the effects of a four week regimen of 50 mg oral DHEA on performance on the digit span, verbal span, and modified Sternberg (Oberauer) tasks. The results demonstrate that the current regimen of drug administration significantly increases serum levels of DHEA, DHEAS, testosterone and estrone and substantially alters the patterns of correlations among the serum levels of these hormones. Despite this substantial change in the hormonal milieu, DHEA administration produced no beneficial effects on cognitive performance in the digit span, verbal span, or modified Sternberg paradigm tasks. Ancillary analyses of the relation between hormone levels and cognitive performance demonstrated a strong positive correlation between DHEA levels and performance on digit span forward/backward and verbal span forward in the placebo drug condition, but not in the DHEA condition. We interpret the juxtaposition of the null results of DHEA administration and the correlation of DHEA levels and performance in the placebo condition to indicate that the referenced correlations arise because a third variable (i.e., age) is associated with both performance and DHEA levels. Additional analyses supported this hypothesis.
本研究考察了给予脱氢表雄酮(DHEA)对短期记忆的影响。本实验采用双盲安慰剂对照交叉设计,探讨了为期四周的 50mg 口服 DHEA 治疗方案对数字跨度、言语跨度和改良 Sternberg(Oberauer)任务表现的影响。结果表明,目前的药物治疗方案显著增加了血清 DHEA、DHEAS、睾酮和雌酮水平,并显著改变了这些激素血清水平之间的相关模式。尽管激素环境发生了实质性变化,但 DHEA 给药对数字跨度、言语跨度或改良 Sternberg 范式任务中的认知表现没有产生有益影响。对激素水平与认知表现之间关系的辅助分析表明,在安慰剂药物条件下,DHEA 水平与数字跨度向前/向后和言语跨度向前呈强烈正相关,但在 DHEA 条件下则没有。我们将 DHEA 给药的无效结果与安慰剂条件下 DHEA 水平与表现的相关性并列在一起,表明上述相关性是因为第三个变量(即年龄)与表现和 DHEA 水平都有关。额外的分析支持了这一假设。