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851.
Previous research has shown that content representations in working memory (WM) can bias attention in favor of matching stimuli in the scene. Using a visual prior-entry procedure, we here investigate whether such WM-driven attention shifts can speed up the conscious awareness of memory-matching relative to memory-mismatching stimuli. Participants were asked to hold a color cue in WM and to subsequently perform a temporal order judgment (TOJ) task by reporting either of two different-colored circles (presented to the left and right of fixation with a variable temporal interval) as having the first onset. One of the two TOJ circles could match the memory cue in color. We found that awareness of the temporal order of the circle onsets was not affected by the contents of WM, even when participants were explicitly informed that one of the TOJ circles would always match the WM contents. The null effect of WM on TOJs was not due to an inability of the memory-matching item to capture attention, since response times to the target in a follow-up experiment were improved when it appeared at the location of the memory-matching item. The present findings suggest that WM-driven attention shifts cannot accelerate phenomenal awareness of matching stimuli in the visual field.  相似文献   
852.
The present study extends the feedback-seeking behavior literature by investigating how supervisor-related antecedents (i.e., supervisors' expert power, reflected appraisals of supervisors, and supervisors' emotional intelligence) influence subordinates' negative feedback-seeking behavior (NFSB) through different cost/value perceptions (i.e., expectancy value, self-presentation cost, and ego cost). Using data collected from 216 supervisor-subordinate dyads from various industries in Taiwan, we employ structural equation modeling analysis to test our hypotheses. The results show that expectancy value mediates the relationship between supervisor expert power and subordinates' NFSB. Moreover, self-presentation cost mediates the relationship between reflected appraisals of supervisors' and subordinates' NFSB. Theoretical and practical implications of this study are also discussed.  相似文献   
853.
The purpose was to examine differences in verbal interactions during the group counseling process and the relationship between perceived verbal interactions and members' demographic variables. 42 participants were recruited and randomly assigned to one of four counseling groups. Based on the Hill Interaction Matrix, Quadrant 4 verbal interactions, consisting of Speculative and Confrontative verbal behaviors in Personal and Relationship levels, were perceived significantly more often at the closing stage than at the initial stage. Furthermore, the perceived verbal interactions were related to the demographic variables of sex, educational level, and group experience, but not acquaintanceship. The findings suggested that the higher ratings of perceived Speculative and Confrontative verbal behaviors and the lower ratings of Assertive and Silence verbal interactions must be interpreted cautiously from a cross-cultural perspective, especially in Asian cultures.  相似文献   
854.
The most common way to induce fluency using rhythm requires persons who stutter to speak one syllable or one word to each beat of a metronome, but stuttering can also be eliminated when the stimulus is of a particular duration (e.g., 1 second [s]). The present study examined stuttering frequency, speech production changes, and speech naturalness during rhythmic speech that alternated 1 s of reading with 1 s of silence. A repeated-measures design was used to compare data obtained during a control reading condition and during rhythmic reading in 10 persons who stutter (PWS) and 10 normally fluent controls. Ratings for speech naturalness were also gathered from naïve listeners. Results showed that mean vowel duration increased significantly, and the percentage of short phonated intervals decreased significantly, for both groups from the control to the experimental condition. Mean phonated interval length increased significantly for the fluent controls. Mean speech naturalness ratings during the experimental condition were approximately “7” on a 1–9 scale (1 = highly natural; 9 = highly unnatural), and these ratings were significantly correlated with vowel duration and phonated intervals for PWS. The findings indicate that PWS may be altering vocal fold vibration duration to obtain fluency during this rhythmic speech style, and that vocal fold vibration duration may have an impact on speech naturalness during rhythmic speech. Future investigations should examine speech production changes and speech naturalness during variations of this rhythmic condition.Educational objectives: The reader will be able to: (1) describe changes (from a control reading condition) in speech production variables when alternating between 1 s of reading and 1 s of silence, (2) describe which rhythmic conditions have been found to sound and feel the most natural, (3) describe methodological issues for studies about alterations in speech production variables during fluency-inducing conditions, and (4) describe which fluency-inducing conditions have been shown to involve a reduction in short phonated intervals.  相似文献   
855.
Lai J  Poletiek FH 《Cognition》2011,(2):265-273
A theoretical debate in artificial grammar learning (AGL) regards the learnability of hierarchical structures. Recent studies using an AnBn grammar draw conflicting conclusions (Bahlmann and Friederici, 2006 and [De Vries et al., 2008] ). We argue that 2 conditions crucially affect learning AnBn structures: sufficient exposure to zero-level-of-embedding (0-LoE) exemplars and a staged-input. In 2 AGL experiments, learning was observed only when the training set was staged and contained 0-LoE exemplars. Our results might help understanding how natural complex structures are learned from exemplars.  相似文献   
856.
Temporal association learning (TAL) allows for the linkage of distinct, nonsynchronous events across a period of time. This function is driven by neural interactions in the entorhinal cortical–hippocampal network, especially the neural input from the pyramidal cells in layer III of medial entorhinal cortex (MECIII) to hippocampal CA1 is crucial for TAL. Successful TAL depends on the strength of event stimuli and the duration of the temporal gap between events. Whereas it has been demonstrated that the neural input from pyramidal cells in layer II of MEC, referred to as Island cells, to inhibitory neurons in dorsal hippocampal CA1 controls TAL when the strength of event stimuli is weak, it remains unknown whether Island cells regulate TAL with long trace periods as well. To understand the role of Island cells in regulating the duration of the learnable trace period in TAL, we used Pavlovian trace fear conditioning (TFC) with a 60-sec long trace period (long trace fear conditioning [L-TFC]) coupled with optogenetic and chemogenetic neural activity manipulations as well as cell type-specific neural ablation. We found that ablation of Island cells in MECII partially increases L-TFC performance. Chemogenetic manipulation of Island cells causes differential effectiveness in Island cell activity and leads to a circuit imbalance that disrupts L-TFC. However, optogenetic terminal inhibition of Island cell input to dorsal hippocampal CA1 during the temporal association period allows for long trace intervals to be learned in TFC. These results demonstrate that Island cells have a critical role in regulating the duration of time bridgeable between associated events in TAL.

The linkage of temporally discontiguous events, called temporal association learning (TAL), is an essential function for episodic memory formation; for animals, when an event took place, and in what order a series of events occurred is directly linked to adaptation to continuous changes in the environment (Eichenbaum 2000; Tulving 2002a,b; Kitamura et al. 2015a; Kitamura 2017; Pilkiw and Takehara-Nishiuchi 2018). The entorhinal cortical–hippocampal (EC-HPC) network in particular is currently considered to bridge the temporal discontinuity between events (Solomon et al. 1986; Moyer et al. 1990; Wallenstein et al. 1998; McEchron et al. 1999; Eichenbaum 2000; Huerta et al. 2000; Ryou et al. 2001; Takehara et al. 2003; Chowdhury et al. 2005; Esclassan et al. 2009; Morrissey et al. 2012; Suter et al. 2013; Sellami et al. 2017; Wilmot et al. 2019).Two major excitatory inputs to HPC arise from the superficial layers of the EC (Fig. 1A), forming the direct (monosynaptic), and indirect (trisynaptic) pathways (Amaral and Witter 1989; Amaral and Lavenex 2007; Kitamura 2017; Kitamura et al. 2017). While pyramidal cells in EC layer III (ECIII cells) project directly to CA1 (Kohara et al. 2014; Kitamura et al. 2015b), the trisynaptic pathway originates from excitatory Reelin+ stellate cells in EC layer II (ECII) projecting directly to DG, CA3, and CA2 (Fig. 1B; Tamamaki and Nojyo 1993; Varga et al. 2010). CalbindinD-28K+/Wolfram syndrome 1 (Wfs1)+ pyramidal cells, another excitatory neural population in EC layer II called “Island cells,” form cell clusters along the ECII/ECI border (Alonso and Klink 1993; Fujimaru and Kosaka 1996; Klink and Alonso 1997; Kawano et al. 2009; Varga et al. 2010; Kitamura et al. 2014; Ray et al. 2014) and directly project to the GABAergic interneurons of stratum lacunosum (SL-INs) in HPC CA1 and drive feedforward inhibition to HPC CA1 pyramidal cells (Fig. 1B; Kitamura et al. 2014; Surmeli et al. 2016; Kitamura 2017; Ohara et al. 2018; Yang et al. 2018; Zutshi et al. 2018).Open in a separate windowFigure 1.Circuit schematic diagram of the medial entorhinal cortex (MEC)–hippocampal (HPC) circuit. (A) Major projections in the entorhinal cortical (EC)-HPC network. ECIII neurons (green) project directly to CA1. ECII Ocean cells (ECIIo, purple) project to the dentate gyrus (DG) (light blue)/CA3 (pink) initiating the trisynaptic pathway. ECII Island cells (ECIIi, blue) project directly into CA1. (B) ECIII projections (green) excite the distal portions of CA1 pyramidal cell (yellow) dendrites in the stratum moleculare. Island cells (ECIIi, blue) excite the interneurons of stratum lacunosum (SL-INs, red), which in turn inhibit the distal dendrites of CA1 pyramidal cells in SL.Trace fear conditioning (TFC) has been established as one suitable animal model for TAL (Fendt and Fanselow 1999; Maren 2001; Kim and Jung 2006) that can be also used as a translational bridge between animal and human learning (Clark and Squire 1998; Buchel and Dolan 2000; Delgado et al. 2006). Lesion, pharmacological, molecular, and optogenetic manipulation, as well as disease models in medial entorhinal cortex (MEC), demonstrate that MEC is crucial for TFC and temporal learning (Ryou et al. 2001; Woodruff-Pak 2001; Runyan et al. 2004; Esclassan et al. 2009; Gilmartin and Helmstetter 2010; Suh et al. 2011; Morrissey et al. 2012; Shu et al. 2016; Hales et al. 2018; Yang et al. 2018; Heys et al. 2020). Specifically, MECIII inputs into the HPC CA1 pyramidal cells are essential for the formation of TFC (Yoshida et al. 2008; Suh et al. 2011; Kitamura et al. 2014; Kitamura 2017). However, the temporal association function driven by MECIII neurons must be regulated for optimal adaptive memory formation, as too strong an association of a particular pair of events may interfere with associations of other useful pairs, whereas too weak an association for a given pair of events, in terms of weaker impact of events or longer duration of temporal gap between events, would not result in an effective memory (Kitamura et al. 2015a; Marks et al. 2020). In a naturalistic context, this would mean that more distant/quieter sounds, less intense somatic sensations (e.g., pain), or increased temporal distance between any two events would signal that the events are less likely to be causally associated, therefore less relevant, and less likely to be stored and recalled. In fact, successful TFC depends on the strength of event stimuli and duration of temporal gap between events (Stiedl and Spiess 1997; Misane et al. 2005; Kitamura et al. 2014; Kitamura 2017). However, the underlying regulatory mechanism for TAL remains hidden. Previously we demonstrated that feedforward inhibition by Island cells acts as a gating controller for the MECIII inputs to the distal dendrites of HPC CA1 pyramidal cells in stratum moleculare (SM) (Kitamura et al. 2014) to control TFC when weaker (in this case diminished footshock intensity) unconditioned stimuli were delivered for TFC, indicating that Island cell activity controls the temporal association when the strength of two discontinuous events are relatively weaker. However, the way in which the EC-HPC network regulates TFC with a longer trace period still remains unknown. Because the activation of Island cells would result in a net inhibitory effect on the local network in CA1, imposing a tight and specific regulation on associations of events across the temporal gap in TAL (Crestani et al. 2002; Moore et al. 2010; Kitamura et al. 2014, 2015b), we hypothesized that the length of the temporal gap between events would also be modulated by this mechanism. In this study, we examined the role of the regulatory input to this circuit arising specifically from the Island cells in the MECII using apoptotic elimination of Island cells, chemogenetic neural inhibition, and optogenetic terminal inhibition methods within an L-TFC protocol to give a thorough and complete assessment of the circuit involvement while considering each technique''s unique features.  相似文献   
857.
To establish a valid database of vocal emotional stimuli in Mandarin Chinese, a set of Chinese pseudosentences (i.e., semantically meaningless sentences that resembled real Chinese) were produced by four native Mandarin speakers to express seven emotional meanings: anger, disgust, fear, sadness, happiness, pleasant surprise, and neutrality. These expressions were identified by a group of native Mandarin listeners in a seven-alternative forced choice task, and items reaching a recognition rate of at least three times chance performance in the seven-choice task were selected as a valid database and then subjected to acoustic analysis. The results demonstrated expected variations in both perceptual and acoustic patterns of the seven vocal emotions in Mandarin. For instance, fear, anger, sadness, and neutrality were associated with relatively high recognition, whereas happiness, disgust, and pleasant surprise were recognized less accurately. Acoustically, anger and pleasant surprise exhibited relatively high mean f0 values and large variation in f0 and amplitude; in contrast, sadness, disgust, fear, and neutrality exhibited relatively low mean f0 values and small amplitude variations, and happiness exhibited a moderate mean f0 value and f0 variation. Emotional expressions varied systematically in speech rate and harmonics-to-noise ratio values as well. This validated database is available to the research community and will contribute to future studies of emotional prosody for a number of purposes. To access the database, please contact pan.liu@mail.mcgill.ca.  相似文献   
858.
Accumulating evidence suggests that cognitive declines in old (healthy) animals could arise from depression of intracortical inhibition, for which a decreased ability to produce GABA during senescence might be responsible. By simulating a neural network model of a primary visual cortical (V1) area, we investigated whether and how a lack of GABA affects cognitive performance of the network: detection of the orientation of a visual bar-stimulus. The network was composed of pyramidal (P) cells and GABAergic interneurons such as small (S) and large (L) basket cells. Intrasynaptic GABA-release from presynaptic S or L cells contributed to reducing ongoing-spontaneous (background) neuronal activity in a different manner. Namely, the former exerted feedback (S-to-P) inhibition and reduced the frequency (firing rate) of action potentials evoked in P cells. The latter reduced the number of saliently firing P cells through lateral (L-to-P) inhibition. Non-vesicular GABA-release, presumably from glia and/or neurons, into the extracellular space reduced the both, activating extrasynaptic GABAa receptors and providing P cells with tonic inhibitory currents. By this combinatorial, spatiotemporal inhibitory mechanism, the background activity as noise was significantly reduced, compared to the stimulus-evoked activity as signal, thereby improving signal-to-noise (S/N) ratio. Interestingly, GABA-spillover from the intrasynaptic cleft into the extracellular space was effective for improving orientation selectivity (orientation bias), especially when distractors interfered with detecting the bar-stimulus. These simulation results may provide some insight into how the depression of intracortical inhibition due to a reduction in GABA content in the brain leads to age-related cognitive decline.  相似文献   
859.
谢晔  周军 《心理科学》2012,35(4):951-956
本研究采用双因素被试间实验具体考察了特定即时情绪和框架效应对于捐赠决策的影响,结果发现存在显著的主效应和交互作用。悲伤情绪能够增加捐赠者的捐赠意愿,快乐情绪会降低捐赠者的捐赠意愿;损失框架能够增加捐赠者的捐赠意愿,幸存框架会降低捐赠者的捐赠意愿;快乐情绪的捐赠者的捐赠决策受框架效应的影响要弱于中性情绪和悲伤情绪的捐赠者,捐赠者在幸存框架下的捐赠决策受情绪的影响比在损失框架下受情绪的影响更小。  相似文献   
860.
Selective attention can be improved under conditions in which a high perceptual load is assumed to exhaust cognitive resources, leaving scarce resources for distractor processing. The present study examined whether perceptual load and acute stress share common attentional resources by manipulating perceptual and stress loads. Participants identified a target within an array of nontargets that were flanked by compatible or incompatible distractors. Attentional selectivity was measured by longer reaction times in response to the incompatible than to the compatible distractors. Participants in the stress group participated in a speech test that increased anxiety and threatened self-esteem. The effect of perceptual load interacted with the stress manipulation in that participants in the control group demonstrated an interference effect under the low perceptual load condition, whereas such interference disappeared under the high perceptual load condition. Importantly, the stress group showed virtually no interference under the low perceptual load condition, whereas substantial interference occurred under the high perceptual load condition. These results suggest that perceptual and stress related demands consume the same attentional resources.  相似文献   
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