视觉工作记忆的巩固加工：时程、模式及机制

在视觉工作记忆加工过程中, 对记忆项目的维持及操作需要将转瞬即逝的感觉输入转换为稳定的记忆表征, 这一加工过程被定义为视觉工作记忆巩固。鉴于巩固在视觉工作记忆中所起到的“门控”作用, 研究者们已经发展出多种研究范式对其可能涉及的运作机制进行探讨。然而, 在不同范式下所观察到的巩固时程存在较大差异, 其所遵循的巩固模式也尚不清晰。此外, 对于巩固所涉及的理论及神经机制亦存在不同的观点。通过对比不同范式的差异性及梳理各方的观点, 可以有效推动这些问题的解决。未来研究除了可以在多种范式下对巩固模式进行验证, 还可以探究注意在巩固中的作用, 以及项目熟悉性等因素会对巩固加工产生何种影响。     

Take a break! Benefits of sleep and short breaks for daily work engagement

The current study investigates the benefits of a good night’s sleep and short work breaks for employees’ daily work engagement. It is hypothesized that sleep and self-initiated short breaks help restore energetic and self-regulatory resources which, in turn, enable employees to experience high work engagement. A daily diary study was conducted with 107 employees who provided data twice a day (before lunch and at the end of the working day) over 5 workdays (453 days in total). Multilevel regression analyses showed that sleep quality and short breaks were beneficial for employees’ daily work engagement. After nights employees slept better, they indicated higher work engagement during the day. Moreover, taking self-initiated short breaks from work in the afternoon boosted daily work engagement, whereas taking short breaks in the morning failed to predict daily work engagement. Taking short breaks did not compensate for impaired sleep with regard to daily work engagement. Overall, these findings suggest that recovery before and during work can foster employees’ daily work engagement.     

Obstructive sleep apnoea syndrome increases source‐confusion errors: A pilot study

We explored external source monitoring (i.e., discrimination between memories of two externally derived sources) in patients with obstructive sleep apnoea syndrome (OSAS). Our specific aim was to ascertain whether, relative to controls, patients exhibit more source‐confusion errors when there are similarities between two external memory sources. We recruited 22 patients with OSAS and 22 controls matched for sex, age, and education. The experimental procedure we used came in three phases. First, participants viewed a target film. Second, they were shown a mixed set of photographs, some taken from the film (target photographs), others not (photographs taken from other films not viewed by participants; lures). Lures differed either conceptually or perceptually from the target film. Third, the following day, participants were shown a set of photographs and urged to determine whether the photographs were taken from the target film or whether they were images they had seen for the first time in Phase 2. Patients correctly attributed the same number of target photographs to the target film as controls. By contrast, they incorrectly attributed more lures to the target film than controls did, especially when the lures were semantically similar to the film (perceptual lures). Both perceptual and conceptual source‐confusion errors were significantly correlated with oxygen desaturation during sleep. Results suggest that the higher number of source‐confusion errors observed in patients with OSAS was linked to an impaired ability to recollect specific perceptual details of the study items and that hypoxia is the main contributing factor to this deficit.     

Effect of post-encoding emotion on recollection and familiarity for pictures

Although prior studies have examined the effect of post-encoding emotional arousal on recognition memory for words, it is unknown whether the enhancement effect observed on words generalizes to pictures. Furthermore, prior studies using words have showed that the effect of emotional arousal can be modulated by stimuli valence and delay in emotion induction, but it is unclear whether such modulation can extend to pictures and whether other factors such as encoding method (incidental vs. intentional encoding) can be modulatory. Five experiments were conducted to answer these questions. In Experiment 1, participants encoded a list of neutral and negative pictures and then watched a 3-min neutral or negative video. The delayed test showed that negative arousal impaired recollection regardless of picture valence but had no effect on familiarity. Experiment 2 replicated the above findings. Experiment 3 was similar to Experiment 1 except that participants watched a 3-min neutral, negative, or positive video and conducted free recall before the recognition test. Unlike the prior two experiments, the impairment effect of negative arousal disappeared. Experiment 4, where the free recall task was eliminated, replicated the results from Experiment 3. Experiment 5 replicated Experiments 1 and 2 and further showed that the impairment effects of negative arousal could be modulated by delay in emotion induction but not by encoding method or stimuli valence. Taken together, the current study suggests that the enhancement effect observed on words may not generalize to pictures.     

Active sleep is associated with the face preference in the newborns who familiarized with a responsive face

Aim of this study was to investigate the preferential looking behaviour, subsequent to a familiarization task (8-min) with a previously responsive or motionless face, before and after a sleep cycle. Moreover, the role of the active sleep in memory consolidation of the responsive or motionless faces was explored. Hypotheses were that the newborns undergoing a motionless familiarization will exhibit a novelty effect (preference for the novel face) whereas the newborns undergoing a responsive familiarization will show a familiarity effect (preference for the known face) before and after the sleep cycle; moreover, the amount of active sleep will be associated with the looking time at the known face after a sleep cycle.Forty-five healthy full-term newborns were randomly assigned to two groups (group 1: motionless-familiarization and group 2: responsive-familiarization); in both groups newborns were video-recorded during four post-familiarization face-preference tasks, two of them performed before and two after a sleep cycle.During the pre-sleep-trials, there was not a significant preference for one face in both groups. During the post-sleep trials, the newborns showed a clear preference for the novel face. This effect was more evident in group 1. Only in group 2 there was a significant positive correlation between the active sleep duration and the looking duration at the known-face during the post-sleep trials (r = 0.41; p = 0.040). Multiple regression confirmed that only in the group 2 the total duration of the active sleep was associated with the looking duration at the known-face during the post-sleep trials (Adjusted R² = 0.13; β = 0.41; t = 2.2; p = 0.040).Findings showed that in newborns the face representation can be recalled after a sleep cycle. Moreover, the amount of the active sleep predicted the post-sleep looking toward the known-face only in the newborns who interactively familiarized with the face.     

Subjective age and sleep in middle-aged and older adults

Objective: Chronological age is commonly used to explain change in sleep. The present study examines whether subjective age is associated with change in sleep difficulties across middle adulthood and old age.

Design: Participants were drawn from the second (2004–2005) and third (2013–2014) waves of the Midlife in the United States Survey (MIDUS, N = 2350; Mean Age: 55.54 years), the 2008 and 2014 waves of the Health and Retirement Study (HRS, N = 4066; Mean Age: 67.59 years) and the first (2011) and fourth (2014) waves of the National Health and Aging Trends Survey (NHATS, N = 3541; Mean Age: 76.46). In each sample, subjective age, sleep difficulties, depressive symptoms, anxiety and chronic conditions were assessed at baseline. Sleep difficulties was assessed again at follow-up.

Main outcome measures: Sleep difficulties.

Results: An older subjective age at baseline was related to an increase in sleep difficulties over time in the three samples, and was mediated, in part, through more depressive symptoms, anxiety and chronic conditions. Feeling older was associated with an increased likelihood of major sleeping difficulties at follow-up in the three samples.

Conclusion: Subjective age is a salient marker of individuals’ at risk for poor sleep quality, beyond chronological age.     

Should you Sleep on it? The Effects of Overnight Sleep on Subjective Preference‐based Choice

Conventional wisdom and studies of unconscious processing suggest that sleeping on a choice may improve decision making. Although sleep has been shown to benefit several cognitive tasks, including problem solving, its impact on everyday choices remains unclear. Here we explore the effects of ‘sleeping on it’ on preference‐based decisions among multiple options. In two studies, individuals viewed several attributes describing a set of items and were asked to select their preferred item after a 12‐hour interval that either contained sleep or was spent fully awake. After an overnight period including sleep, individuals showed increases in positive perceptions of the choice set. This finding contrasts with previous research showing that sleep selectively enhances recall for negative information. In addition, this increase in positive recall did not translate into a greater desire to purchase their preferred item or into an overall benefit for choice satisfaction. Time‐of‐day controls were used to confirm that the observed effects could not be explained by circadian influences. Thus, we show that people may feel more positive about the choice options but not more confident about the choice after ‘sleeping on’ a subjective decision. We discuss how the valence of recalled choice set information may be important in understanding the effects of sleep on multi‐attribute decision making and suggest several avenues for future research. Copyright © 2015 John Wiley & Sons, Ltd.     

OSAHS在2型糖尿病发病中的作用与对策

阻塞性睡眠呼吸暂停综合征（obstructive sleep apnea hypopnea syndrome,OSAHS）是一种常见的睡眠呼吸紊乱性疾病,以睡眠时反复发作的上气道部分或完全阻塞为特征。近年发现OSAHS与2型糖尿病之间有着明显的相关性,二者均为心血管疾病的高危因素,合并存在能够严重影响生命质量与预期寿命...     

Sleep EEG changes during adolescence: An index of a fundamental brain reorganization

Delta (1–4 Hz) EEG power in non-rapid eye movement (NREM) sleep declines massively during adolescence. This observation stimulated the hypothesis that during adolescence the human brain undergoes an extensive reorganization driven by synaptic elimination. The parallel declines in synaptic density, delta wave amplitude and cortical metabolic rate during adolescence further support this model. These late brain changes probably represent the final ontogenetic manifestation of nature’s strategy for constructing nervous systems: an initial overproduction of neural elements followed by elimination. Errors in adolescent brain reorganization may cause mental illness; this could explain the typical age of onset of schizophrenia. Longitudinal studies of sleep EEG are enhancing our knowledge of adolescent brain maturation. Our longitudinal study of sleep EEG changes in adolescence showed that delta power, which may reflect frontal cortex maturation, begins its decline between ages 11 and 12 years and falls by 65% by age 17 years. In contrast, NREM theta power begins its decline much earlier. Delta and theta EEG frequencies are important to sleep theory because they behave homeostatically. Surprisingly, these brain changes are unrelated to pubertal maturation but are strongly linked to age. In addition to these (and other) maturational EEG changes, sleep schedules in adolescence change in response to a complex interaction of circadian, social and other influences. Our data demonstrate that the daytime sleepiness that emerges in adolescence is related to the decline in NREM delta as well as to altered sleep schedules. These longitudinal sleep data provide guideposts for studying cognitive and behavioral correlates of adolescent brain reorganization.