Carter Olivia L, Burr David C, Pettigrew John D, Wallis Guy M, Hasler Felix, Vollenweider Franz X
University of Queensland, Australia.
J Cogn Neurosci. 2005 Oct;17(10):1497-508. doi: 10.1162/089892905774597191.
Increasing evidence suggests a link between attention, working memory, serotonin (5-HT), and prefrontal cortex activity. In an attempt to tease out the relationship between these elements, this study tested the effects of the hallucinogenic mixed 5-HT1A/2A receptor agonist psilocybin alone and after pretreatment with the 5-HT2A antagonist ketanserin. Eight healthy human volunteers were tested on a multiple-object tracking task and spatial working memory task under the four conditions: placebo, psilocybin (215 microg/kg), ketanserin (50 mg), and psilocybin and ketanserin. Psilocybin significantly reduced attentional tracking ability, but had no significant effect on spatial working memory, suggesting a functional dissociation between the two tasks. Pretreatment with ketanserin did not attenuate the effect of psilocybin on attentional performance, suggesting a primary involvement of the 5-HT1A receptor in the observed deficit. Based on physiological and pharmacological data, we speculate that this impaired attentional performance may reflect a reduced ability to suppress or ignore distracting stimuli rather than reduced attentional capacity. The clinical relevance of these results is also discussed.
越来越多的证据表明注意力、工作记忆、血清素（5-羟色胺，5-HT）和前额叶皮质活动之间存在联系。为了梳理这些因素之间的关系，本研究测试了致幻性5-HT1A/2A受体混合激动剂裸盖菇素单独使用时以及在先用5-HT2A拮抗剂酮色林预处理后的效果。八名健康人类志愿者在以下四种条件下接受了多目标追踪任务和空间工作记忆任务测试：安慰剂、裸盖菇素（215微克/千克）、酮色林（50毫克），以及裸盖菇素和酮色林。裸盖菇素显著降低了注意力追踪能力，但对空间工作记忆没有显著影响，这表明两项任务之间存在功能分离。用酮色林预处理并没有减弱裸盖菇素对注意力表现的影响，这表明5-HT1A受体在观察到的缺陷中起主要作用。基于生理学和药理学数据，我们推测这种注意力表现受损可能反映了抑制或忽略干扰性刺激的能力下降，而非注意力容量降低。本文还讨论了这些结果的临床相关性。
