Nielson K A, Radtke R C, Jensen R A
Department of Psychology, Southern Illinois University at Carbondale 62901-6502, USA.
Neurobiol Learn Mem. 1996 Sep;66(2):133-42. doi: 10.1006/nlme.1996.0054.
We recently demonstrated in human subjects that muscle-tension-induced arousal can enhance later retention performance and that this effect is attenuated by beta-adrenergic receptor antagonists. In that study, each subject established a baseline for muscle tension by squeezing a hand dynamometer for 30 s with maximum force. This may have served to "prime" subsequent arousal produced by muscle tension. Two experiments were performed to address this issue. At the beginning of each experiment, young adult subjects were asked to squeeze the hand dynamometer at maximum effort either for 30 s (Prime) or for only 1 s (No prime). Then, during the task, arousal was induced by having each subject exert a moderate amount of tension (25 to 50% of baseline maximum). In the first experiment, subjects were shown four consecutive lists of 20 highly imageable nouns, given immediate recall tests of each, and then given a comprehensive recall and recognition test at the conclusion of the experiment. Moderate arousal was induced once for each list (at encoding, consolidation, or retrieval) or not at all for one list. The sequence of arousal induction was counterbalanced. Significant enhancement of delayed recall was seen in the 30-s group for those lists in which arousal was induced during the consolidation or retrieval period with no significant effects in the 1-s group. These results demonstrate that arousal can modulate memory consolidation when induced shortly after learning and that an initial priming event may affect the response to subsequent similar arousing events. In the second experiment, subjects read paragraphs, some of which contained highlighted words (working memory task); half of the subjects were given the 30-s procedure and half the 1-s procedure. Only those subjects in the 30-s group showed significant arousal-induced enhancement of delayed recognition of the highlighted words. Again, no significant effect on retention performance was seen in the group that squeezed the hand dynamometer for only 1 s during the priming period. Pulse data suggested that there may be somewhat greater heart-rate reactivity in the 30-s group. These findings suggest that memory modulation by arousal may be primed, or enhanced, by a relevant preliminary arousal event.
我们最近在人体受试者中证明，肌肉紧张诱导的觉醒可以提高随后的记忆保持表现，并且这种效应会被β-肾上腺素能受体拮抗剂减弱。在该研究中，每个受试者通过用最大力量挤压握力计30秒来建立肌肉紧张的基线。这可能起到了“启动”随后由肌肉紧张产生的觉醒的作用。进行了两项实验来解决这个问题。在每个实验开始时，要求年轻成年受试者以最大努力挤压握力计30秒（启动组）或仅挤压1秒（无启动组）。然后，在任务期间，通过让每个受试者施加适度的紧张程度（基线最大值的25%至50%）来诱导觉醒。在第一个实验中，向受试者展示四个连续的包含20个高度形象化名词的列表，对每个列表进行即时回忆测试，然后在实验结束时进行全面的回忆和识别测试。对每个列表诱导一次适度觉醒（在编码、巩固或检索时），或者对一个列表完全不诱导觉醒。觉醒诱导的顺序是平衡的。在30秒组中，对于那些在巩固或检索期间诱导觉醒的列表，延迟回忆有显著增强，而在1秒组中没有显著影响。这些结果表明，觉醒在学习后不久诱导时可以调节记忆巩固，并且一个初始的启动事件可能会影响对随后类似觉醒事件的反应。在第二个实验中，受试者阅读段落，其中一些段落包含突出显示的单词（工作记忆任务）；一半的受试者接受30秒程序，一半接受1秒程序。只有30秒组的受试者表现出由觉醒诱导的对突出显示单词的延迟识别显著增强。同样，在启动期仅挤压握力计1秒的组中，对记忆保持表现没有显著影响。脉搏数据表明，30秒组可能存在稍大的心率反应性。这些发现表明，觉醒对记忆的调节可能会被一个相关的初步觉醒事件启动或增强。
