Are historic years understood as numbers or events? An fMRI study of numbers with semantic associations

While numbers generally cue processing of quantity or order, they can also contain semantic information, as in the case of historic years (e.g., “1492” calls forth associations of Columbus sailing the ocean blue). Whether these dates are processed as quantities or events may depend on the context in which they occur. We examined such “ambiguous number” processing in two different contexts using a paired-comparison task, recording both behavioral responses and brain activity. Participants were either asked to think of all items as numbers and to choose the larger number, or were told to treat the comparators as events and to choose the later event. Behaviorally, all events showed a normal distance effect, establishing that they may be understood and compared in an ordinal sequence. Functional magnetic resonance imaging (fMRI) demonstrated significant differences between years when treated as numbers versus as events. Dates in both contexts shared activity in parietal lobe regions previously implicated in number processing. Dates as numbers showed no extra-numeric activity, while dates thought of as events evoked activity in temporal semantic processing and frontal semantic retrieval areas. These differences suggest that extra-numeric information may be easily accessed and incorporated during processing when supported by even a weak context. This work supports previous studies showing a dissociation between quantity and meaning, and illustrates the brain areas involved in these different aspects.     

Does a sensory processing deficit explain counting accuracy on rapid visual sequencing tasks in adults with and without dyslexia?

The experiments conducted aimed to investigate whether reduced accuracy when counting stimuli presented in rapid temporal sequence in adults with dyslexia could be explained by a sensory processing deficit, a general slowing in processing speed or difficulties shifting attention between stimuli. To achieve these aims, the influence of the inter-stimulus interval (ISI), stimulus duration, and sequence length were evaluated in two experiments. In the first that used skilled readers only, significantly more errors were found with presentation of long sequences when the ISI or stimulus durations were short. Experiment 2 used a wider range of ISIs and stimulus durations. Compared to skilled readers, a group with dyslexia had reduced accuracy on two-stimulus sequences when the ISI was short, but not when the ISI was long. Although reduced accuracy was found on all short and long sequences by the group with dyslexia, when performance on two-stimulus sequences was used as an index of sensory processing efficiency and controlled, group differences were found with presentation of stimuli of short duration only. We concluded that continuous, repetitive stimulation to the same visual area can produce a capacity limitation on rapid counting tasks in all readers when the ISIs or stimulus durations are short. While reduced accuracy on rapid sequential counting tasks can be explained by a sensory processing deficit when the stimulus duration is long, slower processing speed in the group with dyslexia explains the greater inaccuracy found as sequence length is increased when the stimulus duration is short.     

Do conscious perception and unconscious processing rely on independent mechanisms? A meta-contrast study

There is currently no consensus regarding what measures are most valid to demonstrate perceptual processing without awareness. Likewise, whether conscious perception and unconscious processing rely on independent mechanisms or lie on a continuum remains a matter of debate. Here, we addressed these issues by comparing the time courses of subjective reports, objective discrimination performance and response priming during meta-contrast masking, under similar attentional demands. We found these to be strikingly similar, suggesting that conscious perception and unconscious processing cannot be dissociated by their time course. Our results also demonstrate that unconscious processing, indexed by response priming, occurs, and that objective discrimination performance indexes the same conscious processes as subjective visibility reports. Finally, our results underscore the role of attention by showing that how much attention the stimulus receives relative to the mask, rather than whether processing is measured by conscious discrimination or by priming, determines the time course of meta-contrast masking.     

The impact of aging and hearing status on verbal short-term memory

The aim of this study is to assess the impact of hearing status on age-related decrease in verbal short-term memory (STM) performance. This was done by administering a battery of verbal STM tasks to elderly and young adult participants matched for hearing thresholds, as well as to young normal-hearing control participants. The matching procedure allowed us to assess the importance of hearing loss as an explanatory factor of age-related STM decline. We observed that elderly participants and hearing-matched young participants showed equal levels of performance in all verbal STM tasks, and performed overall lower than the normal-hearing young control participants. This study provides evidence for recent theoretical accounts considering reduced hearing level as an important explanatory factor of poor auditory-verbal STM performance in older adults.     

Decision-specific reinvestment scale: An exploration of its construct validity,and association with stress and coping appraisals

ObjectiveThis research project aimed to explore the construct validity of the Decision-Specific Reinvestment Scale (DSRS); more specifically, its links with stress and coping appraisals.DesignStudy 1 validated the DSRS and the Movement-Specific Reinvestment Scale (MSRS) to the French language, in order to examine the construct validity of the DSRS using the MSRS, the Preference for Intuition and Deliberation (PID) inventory and the Melbourne Decision-Making Questionnaire (MDMQ). In addition, sex differences in reinvestment were investigated. Study 2 examined stress and coping appraisals of high and low reinvesters.MethodIn study 1, 379 athletes completed the DSRS, MSRS, PID, and MDMQ. In study 2, 100 handball players, classified as low and high reinvesters, completed surveys aimed to assess stressor intensity, stressor perceived controllability, coping effectiveness, subjective performance and coping strategies with the Coping Inventory for Competitive Sport over three games.ResultsIn study 1, we found that intuitive athletes scored lower on the DSRS in comparison to deliberative athletes, whilst no difference was found for the MSRS. Convergent and discriminant validity was illustrated with the subscales of the MDMQ. No sex differences were found regarding reinvestment. In study 2, findings showed that low reinvesters scored higher than high reinvesters in terms of stressor perceived controllability, coping effectiveness and subjective performance.DiscussionIn addition to confirmation of construct validity, these findings strengthen our understanding of how high decision reinvesters perceive a pressured situation. Key applications are derived from our findings informing coaches and athletes in offsetting the negative effects of reinvestment on sport performance.     

不同搜索情境下老化对自上而下注意加工的影响

在视觉搜索过程中,老年人是否可以在不同情境下调节自上而下和自下而上的加工水平尚不明确。为了探讨老化对认知灵活性的影响,研究采用空间线索范式,通过比较有效线索和无效线索来考察对线索的注意加工水平（注意捕获、注意抑制）,通过比较目标相关和目标无关线索的注意加工水平来考察自上而下和自下而上的作用,通过改变分心物一致性来调控不同的目标凸显情境。结果发现,年轻组在目标非凸显时的空间线索效应高于目标凸显时,表明年轻人会依据目标凸显性调整自上而下的加工水平;但老年组却没有产生这种差异,其更依赖自上而下的加工,注意系统会对目标相关的线索进行注意捕获,对目标无关的线索进行注意抑制。结果表明,随着年龄的增长,认知控制的灵活性下降,表现出对自上而下加工较多的依赖;此外,老年人依然保留着注意捕获和注意抑制的能力,这对认知老化中抑制能力受损的观点提出了挑战。     

词语后情绪环境对语义和感知加工的影响

词语后情绪环境对其中的事件记忆产生影响,但是事件后情绪环境如何影响记忆加工仍不清楚。不同的情绪环境理论—“唤醒偏向竞争理论”,“拓宽-建构理论”,“记忆中心的积极情绪促进理论”支持情绪促进的不同本质。已有的研究表明,注意在情绪记忆中有重要作用。实验一、实验二分别探讨词语后情绪环境对其语义加工与内源源加工和外源源加工的影响。与中性环境相比,积极与消极情绪环境阻碍了外源源特征的加工; 与中性环境和积极情绪环境相比,消极情绪环境阻碍了内源源特征的加工。实验结果支持“唤醒偏向竞争理论”,同时表明“评估”和“注意放置”在情绪环境影响中的重要作用。     

中文文本熟悉性在词切分和词汇识别中的作用

基于E-Z读者模型和中文阅读的整合模型, 词切分和词汇识别是否属于交互作用的统一过程存在争议。通过转换阅读方向来操纵文本熟悉性, 研究其在词切分和词汇识别中的作用。实验1考察中文文本熟悉性和词间空格促进作用之间的权衡。使用Eyelink 1000记录40名大学生在中文阅读中的眼动特征。结果发现：词间空格对中文阅读的促进作用在阅读训练后消失, 表明中文阅读中文本熟悉性和词间空格的促进作用之间存在权衡。实验2操纵文本熟悉性和词频来探究文本熟悉性在词汇识别中的作用, 结果发现：文本熟悉性和词频在早期指标上的交互作用; 阅读训练和词频不存在交互作用, 表明文本熟悉性影响词汇识别的早期加工阶段。研究结果表明中文阅读的词切分和词汇识别可能是顺序加工, 支持E-Z读者模型。