Arousal enhanced memory retention is eliminated following temporal lobe resection

The amygdala, situated in the anterior medial temporal lobe (MTL), is involved in the emotional enhancement of memory. The present study evaluated whether anterior MTL-resections attenuated arousal induced memory enhancement for pictures. Also, the effect of MTL-resections on response latencies at retrieval was assessed. Thirty-one patients with unilateral MTL-resections (17 left, 14 right) together with 16 controls participated in a forced choice memory task with pictorial stimuli varying in arousal. Response latencies increased with stimulus arousal in controls but not in patients. This was paralleled by attenuated recognition memory for moderately and highly arousing pictures in MTL-resectioned patients as compared to healthy controls. However, patients and controls did not differ in memory performance for non-arousing pictures. These results suggest that the MTL is necessary for arousal induced memory enhancement.     

Temporal processing capabilities in repetition conduction aphasia

This study investigates the temporal resolution capacities of the central-auditory system in a subject (NP) suffering from repetition conduction aphasia. More specifically, the patient was asked to detect brief gaps between two stretches of broadband noise (gap detection task) and to evaluate the duration of two biphasic (WN-3) continuous noise elements, starting with white noise (WN) followed by 3 kHz bandpass-filtered noise (duration discrimination task). During the gap detection task, the two portions of each stimulus were either identical (“intra-channel condition”) or differed (“inter-channel condition”) in the spectral characteristics of the leading and trailing acoustic segments. NP did not exhibit any deficits in the intra-channel condition of the gap detection task, indicating intact auditory temporal resolution across intervals of 1–3 ms. By contrast, the inter-channel condition yielded increased threshold values. Based upon the “multiple-looks” model of central-auditory processing, this profile points at a defective integration window operating across a few tens of milliseconds – a temporal range associated with critical features of the acoustic speech signal such as voice onset time and formant transitions. Additionally, NP was found impaired during a duration discrimination task addressing longer integration windows (ca. 150 ms). Concerning speech, this latter time domain approximately corresponds to the duration of stationary segmental units such as fricatives and long vowels. On the basis of our results we suggest, that the patient’s auditory timing deficits in non-speech tasks may account, at least partially, for his impairments in speech processing.     

内侧颞叶与来源记忆

来源记忆不同于项目记忆。早期的研究认为来源记忆的神经基础主要是前额叶,但近几年的相关研究发现内侧颞叶在来源记忆中的作用也是相当重要的,健康被试的功能神经成像研究和内侧颞叶损伤病人研究都为内侧颞叶在来源记忆中的作用提供了可靠证据。     

Using temporal logics of knowledge for specification and verification—a case study

Temporal logics of knowledge are useful for reasoning about situations where the knowledge of an agent or component is important, and where change in this knowledge may occur over time. Here we use temporal logics of knowledge to reason about the game Cluedo. We show how to specify Cluedo using temporal logics of knowledge and prove statements about the knowledge of the players using a clausal resolution calculus for this logic. We discuss the advantages and disadvantages of using this logic to specify and verify the game Cluedo and describe related implementations.     

语义启动效应的脑机制研究综述

文章主要介绍了语义启动的过程及其脑机制的研究进展。启动效应是内隐记忆的研究焦点,而语义启动是通过刺激的语义特征来研究启动效应的。语义启动的脑机制研究一般是通过脑损伤、脑成像和ERPs等方法实现的。研究表明,大脑的广泛区域都参与着语义启动过程,尤其是脑前区和大脑的左半球。     

Infant-adult vocal interaction dynamics depend on infant vocal type,child-directedness of adult speech,and timeframe

This study explored the temporal contingencies between infant and adult vocalizations as a function of the type of infant vocalization, whether adult caregivers’ vocalizations were infant-directed or other-directed, and the timescale of analysis. We analyzed excerpts taken from day-long home audio recordings that were collected from nineteen 12- to 13-month-old American infants and their caregivers using the LENA system. Three 5-minute sections having high child vocalization rates were identified within each recording and coded by trained researchers. Infant and adult vocalizations were sequenced and defined as contingent if they occurred within 1 s, 2 s, or 5 s of each other. When using 1 s or 2 s definitions of temporal adjacency, infant vocalizations generally predicted subsequent infant-directed adult vocalizations. A reflexive vocalization (i.e. a cry or a laugh) was the strongest predictor. Likewise, within 1–2 s timeframes, infant-directed adult speech generally predicted infant vocalizations with reflexive vocalizations being particularly predictive. Infant vocalizations predicted fewer subsequent other-directed adult vocalizations and were less likely following other-directed adult vocalizations when considering up to 5 s lags. This suggests an understudied communicative role for infants of non-infant-directed adult speech. These results demonstrate the importance of timescale in studying infant-adult interactions, support the communicative significance of reflexive infant vocalizations and other-directed adult speech in addition to more commonly studied vocalization types, and highlight the challenges of determining direction(s) of influence when using only two-event sequences.     

语言理解中语义整合的神经机制

语义整合是语言阅读理解中非常重要的环节。随着认知神经科学技术的广泛应用,当前关于语义整合的研究取得了长足进步,各种模型层出不穷。但是不同模型对于语义整合的功能定位及其内在机制却存在较大的争议。本文首先介绍当前关于语义整合的主要模型,然后对当前不同理论模型之间关于语义整合的界定,以及语义整合的功能定位是在额下回还是颞叶的争论进行了分析。我们认为,关于语义整合的实质、语义整合的功能网络将是未来研究的主要方向,相关的研究对于语言理解理论的发展将具有重要的启示。     

The role of the magnocellular and parvocellular pathways in the attentional blink

The attentional blink refers to the transient impairment in perceiving the 2nd of two targets presented in close temporal proximity in a rapid serial visual presentation (RSVP) stream. The purpose of this study was to examine the effect on human attentional-blink performance of disrupting the function of the magnocellular pathway--a major visual-processing pathway specialized in temporal segregation. The study was motivated by recent theories that relate the attentional blink to the limited temporal resolution of attentional responses, and by a number of poorly understood empirical findings, including the effects on the attentional blink of luminance adaptation and distraction. The attentional blink was assessed for stimuli on a red background (Experiment 1), stimuli on an equiluminant background (Experiment 2), and following flicker or motion adaptation (Experiment 3), three psychophysical manipulations known to disrupt magnocellular function. Contrary to our expectations, the attentional blink was not affected by these manipulations, suggesting no specific relationship between the attentional blink and magnocellular and/or parvocellular processing.     

Does attention impair temporal discrimination? Examining non-attentional accounts

Recently, Yeshurun and Levy (Psychol Sci 14:225-231, 2003) have provided evidence for the notion that visual attention impairs the temporal resolution of the visual system. Specifically, the detection of a temporal gap within a visual stimulus was impaired when a cue directed attention towards the spatial location of the stimulus. As this negative cueing effect is important to constrain theories about visual attention, we further investigated this novel effect and assessed whether it truly reflects an attentional effect. Experiment 1 examines whether the negative cueing effect is due to local temporal interference, and Experiments 2 and 3 investigate whether it reflects a luminance confound. The complete pattern of results argues against these alternatives and thus further strengthens the conclusion of Yeshurun and Levy (Psychol Sci 14: 225-231, 2003).     

PTSD青少年对威胁图片注意偏向的时程特点及习惯化倾向

探讨创伤后应激障碍(post-traumatic stress disorder,PTSD)青少年(n=20)与创伤控制组(n=20)对威胁图片注意偏向的时间进程特点以及习惯化倾向.在线索提示任务中,图片的呈现时间为100ms、500ms和1250ms.研究表明:(1)在时间进程上,当图片呈现100ms时,创伤控制组对地震图存在注意警觉;当呈现时间为500ms时,两组被试对负性图和地震图存在注意回避;当呈现时间为1250ms时,PTSD组对负性图仍存在注意回避、对地震图的注意偏向消失,创伤控制组对负性图和地震图的注意偏向均消失.(2)在习惯化倾向上,当第六次呈现威胁图片时,PTSD组对负性图和地震图的注意偏向消失,而创伤控制组对负性图和地震图的注意回避仍未消失.