视觉客体在工作记忆中的累积构建

本研究采用变化觉察范式,以包含高、低空间频率信息的形状为刺激材料,探讨客体表征在工作记忆中的构建。结果发现,低频形状的工作记忆绩效显著优于高频形状,且二者辨别力的差别随SOA延长逐渐消失,说明低频信息优先进入视觉工作记忆。该结果支持工作记忆中客体表征的构建并非采用"全或无"的方式,而可能采用累积加工方式的假设。     

How does information from low and high spatial frequencies interact during scene categorization?

Current models of visual perception suggest that, during scene categorization, low spatial frequencies (LSF) are rapidly processed and activate plausible interpretations of visual input. This coarse analysis would be used to guide subsequent processing of high spatial frequencies (HSF). The present study aimed to further examine how information from LSF and HSF interact and influence each other during scene categorization. In a first experimental session, participants had to categorize LSF and HSF filtered scenes belonging to two different semantic categories (artificial vs. natural). In a second experimental session, we used hybrid scenes as stimuli made by combining LSF and HSF from two different scenes which were semantically similar or dissimilar. Half of the participants categorized LSF scenes in hybrids, and the other half categorized HSF scenes in hybrids. Stimuli were presented for 30 or 100?ms. Session 1 results showed better performance for LSF than HSF scene categorization. Session 2 scene categorization was faster when participants attended and categorized LSF than HSF scene in hybrids. The semantic interference of a semantically dissimilar HSF scene on LSF scene categorization was greater than the semantic interference of a semantically dissimilar LSF scene on HSF scene categorization, irrespective of exposure duration. These results suggest a LSF advantage for scene categorization, and highlight the prominent role of HSF information when there is uncertainty about the visual stimulus, in order to disentangle between alternative interpretations.     

Recognition memory for low- and high-frequency-filtered emotional faces: Low spatial frequencies drive emotional memory enhancement,whereas high spatial frequencies drive the emotion-induced recognition bias

This article deals with two well-documented phenomena regarding emotional stimuli: emotional memory enhancement—that is, better long-term memory for emotional than for neutral stimuli—and the emotion-induced recognition bias—that is, a more liberal response criterion for emotional than for neutral stimuli. Studies on visual emotion perception and attention suggest that emotion-related processes can be modulated by means of spatial-frequency filtering of the presented emotional stimuli. Specifically, low spatial frequencies are assumed to play a primary role for the influence of emotion on attention and judgment. Given this theoretical background, we investigated whether spatial-frequency filtering also impacts (1) the memory advantage for emotional faces and (2) the emotion-induced recognition bias, in a series of old/new recognition experiments. Participants completed incidental-learning tasks with high- (HSF) and low- (LSF) spatial-frequency-filtered emotional and neutral faces. The results of the surprise recognition tests showed a clear memory advantage for emotional stimuli. Most importantly, the emotional memory enhancement was significantly larger for face images containing only low-frequency information (LSF faces) than for HSF faces across all experiments, suggesting that LSF information plays a critical role in this effect, whereas the emotion-induced recognition bias was found only for HSF stimuli. We discuss our findings in terms of both the traditional account of different processing pathways for HSF and LSF information and a stimulus features account. The double dissociation in the results favors the latter account—that is, an explanation in terms of differences in the characteristics of HSF and LSF stimuli.     

Behavioral assessment of emotional and motivational appraisal during visual processing of emotional scenes depending on spatial frequencies

Previous studies performed on visual processing of emotional stimuli have revealed preference for a specific type of visual spatial frequencies (high spatial frequency, HSF; low spatial frequency, LSF) according to task demands. The majority of studies used a face and focused on the appraisal of the emotional state of others. The present behavioral study investigates the relative role of spatial frequencies on processing emotional natural scenes during two explicit cognitive appraisal tasks, one emotional, based on the self-emotional experience and one motivational, based on the tendency to action. Our results suggest that HSF information was the most relevant to rapidly identify the self-emotional experience (unpleasant, pleasant, and neutral) while LSF was required to rapidly identify the tendency to action (avoidance, approach, and no action). The tendency to action based on LSF analysis showed a priority for unpleasant stimuli whereas the identification of emotional experience based on HSF analysis showed a priority for pleasant stimuli. The present study confirms the interest of considering both emotional and motivational characteristics of visual stimuli.     

Generalizing parametric models by introducing trial-by-trial parameter variability: The case of TVA

We identify two biases in the traditional use of Bundesen’s Theory of Visual Attention (TVA) and show that they can be substantially reduced by introducing trial-by-trial variability in the model. We analyze whole and partial report data from a comprehensive empirical study with 347 participants and elaborate on Bayesian model selection theory for quantifying the advantage of trial-by-trial generalization in general. The analysis provides strong evidence of trial-by-trial variation in both the VSTM capacity parameter and perceptual threshold parameter of TVA. On average, the VSTM capacity bias was found to be at least half an item, while the perceptual threshold parameter was found to be underestimated by about 2 ms.     

Visual attribute modulates the time course of iconic memory decay

Studies on iconic memory demonstrate that rich information from a visual scene quickly becomes unavailable with the passage of time. The decay rate of iconic memory refers to the dynamics of memory availability. The present study investigated the iconic memory decay of different stimulus attributes that comprised an object. Specifically, in Experiment 1, participants were presented with eight coloured numbers (e.g., red 4) and required to remember only one attribute, either colour or number, over different blocks of trials. The participants then reported the cued attribute in which the cue Stimulus Onset Asynchrony (SOA) from the memory array onset was varied (0, 100, 200, 300, 500, and 1000?ms). We found that numerical information became unavailable more quickly than colour information, despite the fact that the memory accuracies at 0 and 1000?ms SOAs were comparable between the two attributes. In Experiment 2, we replicated the finding that a numerical representation was lost more quickly than a colour representation when visual masks followed the target stimulus. These results suggest that the various visual attributes comprising an object are lost over time at different rates in iconic memory. We discuss this finding in relation to how perceptual representation is transferred to the capacity-limited visual working memory.     

Higher sensitivity for low spatial frequency expressions in social anxiety: Evident in indirect but not direct tasks?

We tested whether socially anxious individuals perform better in processing facial information with low spatial frequencies (LSFs). For this, we presented socially anxious and nonanxious participants with hybrid face stimuli that contained independent facial expressions in high (HSF) and LSF bands. In two tasks, participants either rated the images according to "angriness" or had to learn how hybrid facial expressions predicted the location of an upcoming target. We found mostly additive effects of LSF and HSF information in the rating task for both groups. In contrast, socially anxious participants showed better prediction performance for LSF expressions in the implicit learning task. We conclude that socially anxious participants are more sensitive to facial information within LSFs, but this higher sensitivity may become mostly evident in indirect tasks. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Learning influences the encoding of static and dynamic faces and their recognition across different spatial frequencies

Studies on face recognition have shown that observers are faster and more accurate at recognizing faces learned from dynamic sequences than those learned from static snapshots. Here, we investigated whether different learning procedures mediate the advantage for dynamic faces across different spatial frequencies. Observers learned two faces—one dynamic and one static—either in depth (Experiment 1) or using a more superficial learning procedure (Experiment 2). They had to search for the target faces in a subsequent visual search task. We used high-spatial frequency (HSF) and low-spatial frequency (LSF) filtered static faces during visual search to investigate whether the behavioural difference is based on encoding of different visual information for dynamically and statically learned faces. Such encoding differences may mediate the recognition of target faces in different spatial frequencies, as HSF may mediate featural face processing whereas LSF mediates configural processing. Our results show that the nature of the learning procedure alters how observers encode dynamic and static faces, and how they recognize those learned faces across different spatial frequencies. That is, these results point to a flexible usage of spatial frequencies tuned to the recognition task.     

视觉信息分布调节信息整合策略：来自眼动的证据

以空白单元格定位为实验任务,操纵序列点阵的分布,考察视觉短时记忆与视知觉的信息整合机制。实验一发现任务正确率与点阵1的圆点数呈近似U形关系。实验二发现在拐点前后被试的眼动模式从偏向于注视圆点位置转为偏向于注视空格位置。因此,视觉信息的分布模式调节整合策略,当处于视觉短时记忆中的圆点数在其容量之内时,采用图像—知觉整合策略,反之,则采用转换—比较策略。     

The coarse-to-fine hypothesis revisited: evidence from neuro-computational modeling

The human perceptual system seems to be driven by a coarse-to-fine integration of visual information. Different results have shown a faster integration of low-spatial frequency compared with high-spatial frequency (HSF) information, starting at early retinal processes. The difference in spatial scale decomposition remains throughout the lateral geniculate nucleus (Hubel & Wiesel, 1977) and V1 (Tootell, Silverman, & De Valois, 1981). During the last decade, a debate has emerged concerning the origin of the coarse-to-fine integration. Is it a constant, perceptually driven integration (Parker et al., 1992 and Parker et al., 1996)? Instead, the flexible use hypothesis suggests that different spatial frequency channels could be enhanced depending on the requirement of the task for high-level cognitive processes like categorization (Oliva and Schyns, 1997 and Schyns and Oliva, 1999). In two connectionist simulations, we have shown that global categorization performance could actually be better performed with HSF information when the amount of information is normalized across the different spatial frequency channels. Those results suggest that high-level requirement alone could not explain the coarse-to-fine bias toward LSF information. A hypothesis is proposed concerning the possible implication of the amount of data provided by different spatial frequency channel that might provide the perceptual bias toward LSF information.     

The respective role of low and high spatial frequencies in supporting configural and featural processing of faces

One distinctive feature of processing faces, as compared to other categories, is thought to be the large dependence on configural cues such as the metric relations among features. To test the role of low spatial frequencies (LSFs) and high spatial frequencies (HSFs) in configural and featural processing, subjects were presented with triplets of faces that were filtered to preserve either LSFs (below 8 cycles per face width), HSFs (above 32 cycles per face width), or the full frequency spectrum. They were asked to match one of two probe faces to a target face. The distractor probe face differed from the target either configurally, featurally, or both featurally and configurally. When the difference was at the configural level, performance was better with LSF faces than with HSF faces. In contrast, with a featural difference, a strong performance advantage was found for HSF faces as compared to LSF faces. These results support the dominant role that LSFs play in the configural processing of faces, whereas featural processing is largely dependent on HSFs.     

Mechanisms of priming of pop-out: Stored representations or feature-gain modulations?

Previous research has shown that repetition of a task-relevant attention-capturing feature facilitates popout search. This priming of pop-out effect is due to some residual memory from recent trials. We explore two possible mechanisms of priming of pop-out: a top-down attentional benefit from a memory of the previous target representation that is stored in visual short-term memory (VSTM) and a bottom-up change of attentional gains from perceptual features of the previously attended target. We manipulated participants’ ability to form a memory trace in VSTM by occupying it with a distractor task and found that occupying VSTM did not interfere with priming of pop-out. We next manipulated attentional gains associated with feature values by inserting an irrelevant task between pop-out searches. We found that the color of the target from the intervening perceptual task influenced pop-out search: The current pop-out search was facilitated when the intervening task’s target matched the target color of the pop-out search. These results suggest that priming of pop-out might not be due to a memory trace of the previous targets in VSTM but, rather, might be due to changes in attentional control based on priming from relatively low-level feature representations of previously attended objects.     

注意促进效应的ERP研究

近期发现,采用目标探测任务作为二级任务时,目标探测条件不仅不会削弱,甚至会提高记忆成绩,产生注意促进效应（ABE）。为进一步探究目标探测的作用机制,研究采用事件相关电位（ERP）技术,对比目标与分心条件在编码和提取过程中所诱发的ERP差异。结果表明,两类条件在再认过程中所诱发的ERP差异不仅表现在早期与知觉加工相关的ERP成份上,并且一直持续到了后期与细节提取相关的ERP成分上。由此推测,ABE不仅体现在编码早期的知觉加工阶段,更会延续到后期的复述与精加工。     

The influence of expertise and of physical complexity on visual short-term memory consolidation

We investigated whether the expertise of a perceiver and the physical complexity of a stimulus influence consolidation of visual short-term memory (VSTM) in a S1-S2 (Stimulus 1-Stimulus 2) change detection task. Consolidation is assumed to make transient perceptual representations in VSTM more durable, and it is investigated by postexposure of a mask shortly after offset of the perceived stimulus (S1; 17 to 483?ms). We presented colours, Chinese characters, pseudocharacters, and novel symbols to novices (Germans) or experts of Chinese language (Chinese readers). Physical complexity was manipulated by the number of strokes. Unfamiliar material was remembered worse than familiar material (Experiments 1, 2, and 3). For novices the absolute VSTM performance was better for physically simple than for complex material, whereas for experts the complexity did not matter-Chinese readers memorized Chinese characters (Experiment 3). Articulatory suppression did not change these effects (Experiment 2). We always observed a strong effect of SOA, but this effect was influenced neither by physical complexity nor by expertise; only the length of the interstimulus interval between S1 and the mask was relevant. This was observed even with short stimulus onset asynchrony (SOA) of 100?ms (Experiment 2) and in comparing colours and characters (Experiment 5). However, masks impaired memory if they were presented at the locations of the to-be-memorized items, but not beside them-that is, interference was location-based (Experiment 6). We explain the effect of SOA by the assumption that it takes time to stop encoding of information presented at item locations with the offset of S1. The increasing resistance against interference by irrelevant material appears as consolidation of S1.     

Individual differences in spatial frequency processing in scene perception: the influence of autism-related traits

Previous research suggested that coarse (High Spatial Frequency or HSF) and fine (Low Spatial Frequency or LSF) spatial information are flexibly used at different stages of processing during scene recognition in daily life. We tried to replicate and extend these findings by presenting non-social real-life scenes either as a normal picture, solely defined by LSF or HSF information, or using hybrid images consisting of overlaid LSF and HSF scene information. These were used as (in)congruent prime stimuli, modulating the rapid detection of a normal target picture in a 2-Alternative Forced Choice (2-AFC) categorization task (manmade versus natural). Our results indicated that coarse spatial information was more effective with shorter prime presentation times and fine spatial information required a longer prime presentation to influence participant performance. Interestingly, higher scores on the Autism-Spectrum Quotient questionnaire modified the impact of HSF prime information on target identification and influenced performance when ambiguous hybrid prime information preceded the categorization task.     

视觉长时记忆激活度对促进视觉短时记忆的影响

短时记忆与长时记忆的关系是记忆领域研究的重要内容。基于此, 研究者们就视觉长时记忆是否能促进视觉短时记忆的问题展开了大量研究, 但所得出的结论并不一致。通过不同程度的学习形成不同激活度的视觉长时记忆, 考察对几何图形的视觉长时记忆是否能对变化检测中的短时记忆起到促进作用。结果发现, 低激活水平的视觉长时记忆不能促进视觉短时记忆, 而事先存在且高度激活的视觉长时记忆对视觉短时记忆却具有促进作用; 同时, 随着视觉长时记忆激活水平的提高, 刺激间间隔的效应值也逐渐减小。本研究说明, 视觉长时记忆能否促进视觉短时记忆取决于视觉长时记忆的激活水平, 高激活的视觉长时记忆对阻止视觉短时记忆痕迹的迅速消退具有重要意义。     

Visual binding of English and Chinese word parts is limited to low temporal frequencies

Some perceptual mechanisms manifest high temporal precision, allowing reports of visual information even when that information is restricted to windows smaller than 50 ms. Other visual judgments are limited to much coarser time scales. What about visual information extracted at late processing stages, for which we nonetheless have perceptual expertise, such as words? Here, the temporal limits on binding together visual word parts were investigated. In one trial, either the word 'ball' was alternated with 'deck', or 'dell' was alternated with 'back', with all stimuli presented at fixation. These stimuli restrict the time scale of the rod identities because the two sets of alternating words form the same image at high alternation frequencies. Observers made a forced choice between the two alternatives. Resulting 75% thresholds are restricted to 5 Hz or less for words and nonword letter strings. A similar result was obtained in an analogous experiment with Chinese participants viewing alternating Chinese characters. These results support the theory that explicit perceptual access to visual information extracted at late stages is limited to coarse time scales.     

The Advantage of First Mention in Korean The Temporal Contributions of Syntactic,Semantic, and Pragmatic Factors

Using Korean, we investigated how syntactic, semantic, and pragmatic factors influence the representation of a sentence, in particular, the relative accessibility of different components of a sentence representation. In six experiments, participants performed a probe recognition task after reading each of a series of sentences. We manipulated the rate at which each word of the sentence was presented (250 ms and 500 ms) and the interval between the sentence-final word and the probe-recognition test word (immediate, 500 ms delay, and 1000 ms delay). We also manipulated the syntactic position (subject versus object), semantic role (agent versus patient), and order of mention (first-versus second-mentioned participant) of the probed item. Pragmatic factors (the order of mention) strongly influenced accessibility immediately and through the longest delay, whereas syntactic and semantic factors had little effect.     

The involvement of distinct visual channels in rapid attention towards fearful facial expressions

This paper reports five experiments demonstrating that the low spatial frequency components of faces are critical to the production of rapid attentional responses towards fearful facial expressions. In our main experiments, low spatial frequency (LSF) or high spatial frequency (HSF) face pairs, consisting of one fearful and one neutral expression, were presented on a computer screen for a brief period. Participants were required to identify as quickly as possible the orientation of a bar target that immediately replaced one of the faces. Responses were faster when targets replaced the location of LSF fearful faces, compared with LSF neutral faces. By contrast, there were no differences between responses to targets replacing HSF fearful versus HSF neutral faces. This facilitation in spatial orienting occurred specifically with short time intervals between faces and target, and is consistent with a rapid processing of fear cues from LSF inputs that can serve to guide attention towards threat events.     

Visual short-term memory is not improved by training

A critical question in visual working or short-term memory (VSTM) research is whether the ability to remember briefly presented visual stimuli can be increased. Here we test whether VSTM for locations and shapes is improved by training that allows one to utilize another memory system, visual longterm memory (VLTM). Training was done by repeatedly presenting a subset of memory displays, creating long-term memory traces for these displays. Surprisingly, VSTM performance for repeated displays was not higher than for nonrepeated ones, even though participants recognized repeated displays on a forced-choice test given at the end of the experiment. We suggest that the fidelity of information held by VLTM is inferior to that of information held by VSTM and thus provides no additional benefit over what is extracted on the fly by VSTM.