睡眠对知觉与动作序列内隐学习离线巩固效应的影响

doi:10.3724/SP.J.1041.2022.01467

摘要/Abstract

摘要：

离线阶段发生的学习被称为离线巩固, 即在最初获得知识之后, 即使没有额外的练习, 其记忆痕迹也会保持稳定或提高。有研究初步探究了睡眠对知觉和动作序列内隐学习离线巩固的影响, 然而, 这些研究未能实现知觉序列与动作序列的完全分离, 序列类型是否调节睡眠对内隐序列学习离线巩固的影响仍需进一步探讨。此外, 既往外显学习的研究发现相对于简单的序列, 复杂的序列更容易从睡眠中获益, 表现出基于睡眠的离线巩固效应。睡眠对知觉序列与动作序列内隐学习离线巩固的影响是否会受到序列复杂程度的调节尚不明确。为此, 本研究在完全分离知觉序列和动作序列的情况下, 通过3个实验操纵序列的长度及结构, 设置3种不同复杂程度的序列规则, 考察了这一问题。结果发现, 对于动作序列, 序列规则复杂程度较低时, 无论是否经过睡眠都会发生离线巩固效应, 而当动作序列规则较为复杂时, 只有经历睡眠才会引起离线巩固效应; 对于知觉序列, 无论何种难易程度的规则, 均未发生离线巩固效应。上述结果表明内隐序列知识基于睡眠的离线巩固会受到序列类型及序列复杂程度的调节, 这为内隐学习的离线巩固争论提供了新的视角。

关键词: 睡眠, 内隐学习, 知觉序列, 动作序列, 离线巩固

Abstract:

Implicit learning is integral to human cognition. It occurs during the learning phase (online periods) and the offline interval after the learning phase (offline periods). The process during the offline periods is referred to as consolidation, which means stabilization or enhancement of a memory trace even without additional practice after the initial acquisition. Some studies have preliminarily explored the effect of sleep on the consolidation of perceptual and motor sequences in implicit learning. However, these studies have failed to achieve a complete separation of motor sequences and perceptual sequences, thus leaving open the question of whether the sequence type moderates the effects of sleep on the consolidation of implicit sequence learning. In addition, previous studies of explicit learning have found that sequences with long length and high complexity were more likely to benefit from sleep than simple sequences, showing a sleep-based offline consolidation effect. Therefore, the question of whether the effect of sleep on offline consolidation of implicit learning of perceptual and motor sequences is moderated by sequence complexity remains unresolved.

The present study addressed these issues through three experiments applying different sequence length levels and complexities using a modified version of the Serial Reaction Time (SRT) task, which allows independent manipulation of perceptual and motor sequences. Participants were instructed to press the corresponding key as quickly and accurately as possible according to which color of the target square was the same as that of the surrounding square. In the perceptual sequence group, the target square color followed a sequence, but the finger response orders were randomly assigned. The opposite was true for the motor sequence group. Subsequently, a prediction test was used to estimate the amount of possible explicit knowledge.

Experiment 1 used a short six-element sequence with lower complexity and showed a more robust offline consolidation effect in the motor sequence group compared to the perceptual sequence group. However, sleep does not promote the offline consolidation of both sequences. In Experiment 2, a more complex sequence (sequence length 11) was used. The results showed that participants implicitly learned the motor sequence. In the motor sequence group, participants with sleep performed a better offline consolidation effect than those without sleep. However, participants neither implicitly acquired the sequence nor showed an offline consolidation effect in the perceptual sequence group. Participants performed a small or non-significant perceptual sequence learning effect in Experiments 1 and 2. Based on this result, the sleep-related offline consolidation of the perceptual sequence was further examined using a more simple sequence of length 4 in Experiment 3. The results showed that participants exhibited improvements in the performance of perceptual sequences learning, but no offline consolidation effect was observed in either group.

The combined results of the three experiments showed that sleep does not promote the offline consolidation of perceptual sequences, regardless of the degree of difficulty. For motor sequences, the sequence learning effect significantly increased following sleep but not after waking when the sequence length was long and structural complexity was high. However, sleep-related offline improvements were absent when the sequence length was short. In conclusion, these results indicated that the offline consolidation of implicit sequence knowledge based on sleep is modulated by sequence type and sequence complexity.

Key words: sleep, implicit learning, perceptual sequences, motor sequences, offline consolidation

中图分类号:

B842

孙鹏, 李雪晴, 张庆云, 尚怀乾, 凌晓丽. (2022). 睡眠对知觉与动作序列内隐学习离线巩固效应的影响. 心理学报, 54(12), 1467-1480.

SUN Peng, LI Xueqing, ZHANG Qingyun, SHANG Huaiqian, LING Xiaoli. (2022). Sleep and the consolidation of perceptual and motor sequences in implicit learning. Acta Psychologica Sinica, 54(12), 1467-1480.

图/表 8

图1 A是实验1序列反应时任务(SRT)示意图; B是序列反应时任务流程图。“SRT阶段1”在离线阶段之前进行, “SRT阶段2”在离线阶段之后进行。S指序列组块, R指随机组块。

表1 实验1四组被试的睡眠状况(M ± SD)

组别	睡眠时间	自评分数(1~10评分)	PSQI	MEQ
知觉晚上组	6.89 ± 0.97	7.53 ± 1.71	5.79 ± 3.10	48.74 ± 6.94
动作晚上组	7.18 ± 0.77	8.37 ± 1.50	4.79 ± 2.20	51.42 ± 7.60
知觉白天组	7.13 ± 1.13	7.62 ± 1.32	5.62 ± 1.91	50.14 ± 3.84
动作白天组	7.54 ± 1.03	7.95 ± 0.94	5.80 ± 2.26	52.75 ± 6.05

图2 A是第一阶段的序列学习效应; B是第二阶段的序列学习效应; C是离线巩固效应。误差线代表均值的标准误。 *表示p < 0.05, **表示p < 0.01, ***表示p < 0.001, 下同。

表2 实验2四组被试的睡眠状况(M ± SD)

组别	睡眠时间	自评分数(1~10评分)	PSQI	MEQ
知觉晚上组	6.97 ± 0.72	7.85 ± 1.27	5.90 ± 1.80	49.90 ± 8.96
动作晚上组	7.03 ± 0.60	7.88 ± 1.69	4.71 ± 2.08	53.53 ± 9.18
知觉白天组	6.77 ± 0.83	7.30 ± 1.72	5.35 ± 1.90	46.55 ± 9.94
动作白天组	7.22 ± 0.73	7.72 ± 1.41	5.00 ± 2.70	49.67 ± 5.29

图3 A是第一阶段的序列学习效应; B是第二阶段的序列学习效应; C是离线巩固效应。误差线代表均值的标准误。

图4 实验3序列反应时任务示意图。

表3 实验3晚上组和白天组被试的睡眠状况(M ± SD)

组别	睡眠时间	自评分数(1~10评分)	PSQI	MEQ
晚上组	7.54 ± 0.67	7.80 ± 0.89	5.83 ± 2.55	49.96 ± 8.06
白天组	7.08 ± 1.03	7.13 ± 1.90	6.26 ± 2.90	50.79 ± 9.20

图5 序列学习效应。误差线代表均值的标准误。

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