Is disgust sensitive to classical conditioning as indexed by facial electromyography and behavioural responses?

Earlier studies provided preliminary support for the role of classical conditioning as a pathway of disgust learning, yet this evidence has been limited to self-report. This study included facial electromyographical (EMG) measurements (corrugator and levator muscles) and a behavioural approach task to assess participants’ motivation-to-eat the actual food items (conditioned stimuli, CS). Food items served as CS and film excerpts of a woman vomiting served as unconditioned stimuli (US). Following acquisition the CS+ (neutral CS paired with US disgust) was rated as more disgusting and less positive. Notably, the conditioned response was transferred to the actual food items as evidenced by participants’ reported lowered willingness-to-eat. Participants also showed heightened EMG activity in response to the CS+ which seemed driven by the corrugator indexing a global negative affect. These findings suggest that classical conditioning as a pathway of disgust learning can be reliably observed in subjective but not in disgust-specific physiological responding.     

Dual-tasking alleviated sleep deprivation disruption in visuomotor tracking: an fMRI study

Effects of dual-responding on tracking performance after 49-h of sleep deprivation (SD) were evaluated behaviorally and with functional magnetic resonance imaging (fMRI). Continuous visuomotor tracking was performed simultaneously with an intermittent color-matching visual detection task in which a pair of color-matched stimuli constituted a target and non-matches were non-targets. Tracking error means were binned time-locked to stimulus onset of the detection task in order to observe changes associated with dual-responding by comparing the error during targets and non-targets. Similar comparison was made with fMRI data. Our result showed that despite a significant increase in the overall tracking error post SD, from 20 pixels pre SD to 45 pixels post SD, error decreased to a minimum of about 25 pixels 0-6s after dual-response. Despite an overall reduced activation post SD, greater activation difference between targets and non-targets was found post SD in task-related regions, such as the left cerebellum, the left somatosensory cortex, the left extrastriate cortex, bilateral precuneus, the left middle frontal gyrus, and the left motor cortex. Our results suggest that dual-response helps to alleviate performance impairment usually associated with SD. The duration of the alleviation effect was on the order of seconds after dual-responding.     

熟悉性对被试操作效应的作用:来自无线索回忆再认的证据

在动作事件的再认记忆中,被试操作后的记忆成绩优于单纯的词语记忆(SPT效应)。人们认为操作促进了回想加工,而熟悉性是否对SPT效应起作用仍然存在分歧。研究采用无线索回忆再认范式,考察了信息提取失败时熟悉性对SPT效应的作用。结果显示:(1)SPT和VT两种编码都引发了稳定的无线索回忆再认效应(RWCR效应)。(2)与VT编码相比,SPT编码引发更强的熟悉性加工,表现出无线索回忆再认的记忆优势。上述结果表明,即使无法正确提取细节信息,在SPT编码中被试凭借熟悉性辨认的能力仍然高于VT编码。该结果从信息提取失败的视角为熟悉性对SPT效应的作用提供了更为直接的证据。     

拖延的决策模型

拖延是指尽管预见到该行为会带来不利后果,人们仍自愿推迟开始或完成某一计划好的行为。先前的研究对拖延的类型、影响因素、成因以及干预等方面进行了广泛的探讨,然而拖延的决策过程——\"现在做还是以后做?\"认知机制还非常不清楚。因此,本文提出拖延决策模型试图从三方面阐明\"现在做还是以后做?\"的决策机制:首先,拖延动机和不拖延动机的斗争是决定是否拖延的根本;其次,拖延动机的斗争可以进一步简化为任务负性过程和任务正性结果的权衡;最后,主动推迟任务使负性过程发生延迟折扣是拖延的核心目的。拖延决策模型不仅有助于探明拖延的核心认知机制,也能够帮助预测拖延行为的发生及解释各种影响因素的作用机制,因此未来的研究可以借此整合一个从拖延的核心发生机制到各种影响因素的理论系统。     

背景颜色对一致性序列效应的调节

为满足迅速变化的环境要求,个体需要快速灵活地调整认知加工策略。背景颜色是一个重要的环境因素,它能够影响人的认知和行为表现。然而,背景颜色对认知控制在线调整的影响,是一个关键但又被忽略的问题。为解决这个问题,本研究采用字母flanker任务,考察了灰色、蓝色和红色背景条件下的一致性序列效应。结果发现,蓝色背景下的一致性序列效应不显著,而灰色和红色背景下得到了显著的一致性序列效应;此外,在这三种颜色背景下,flanker干扰效应无显著差异。这些结果说明,蓝色背景影响一致性序列效应,但干扰效应不受背景颜色的调节。当前的研究首次揭示了背景颜色对认知控制在线调整的影响,也进一步加深了我们对一致性序列效应的理解。     

The role of processes and contents in human memory: An item response theory approach

This study investigated the specificities and communalities of visuospatial and verbal memory contents, as well as short-term memory and working memory (STM and WM) processes with the use of Rasch models as an alternative to the previous studies based on the classical test theory. A sample of 547 undergraduate students executed four computerised tasks, each consisting of verbal-numeric WM, visuospatial WM, verbal-numeric STM, and visuospatial STM content. Confirmatory factor analyses indicated that visuospatial and verbal-numeric memory are distinct, but correlated variables. Findings also support a domain-general view of WM capacity distinct from domain-specific storage. With the use of Rasch models, our results confirm previous experimental, psychometric, and neuropsychological studies, highlighting that memory span tasks can be divided into separate subsystems for content and processes. This study also shows that better results are obtained when models with person parameter estimates (provided from Rasch models) are adopted, rather than summed raw scores.