基于名人面孔视觉特征和语义信息的视觉统计学习

视觉统计学习是指个体依据视觉刺激之间的转接概率来掌握统计规律的过程。本研究通过5个实验探讨了个体基于名人面孔视觉特征和语义信息进行视觉统计学习的加工机制。每个实验均包括熟悉(学习)和测试两个阶段：在熟悉阶段, 让被试观看名人面孔并完成重复图片探测的无关任务; 在测试阶段, 让被试进行二选一迫选任务。其中, 实验1和2分别考察基于名人面孔视觉特征和语义信息的视觉统计学习效果; 实验3分别考察基于名人面孔视觉特征和语义信息视觉进行统计学习的精确性; 实验4进一步考察基于名人面孔视觉特征和语义信息进行视觉统计学习的时间特征; 实验5验证基于名人面孔视觉特征的视觉统计学习具有面孔特异性。结果表明：个体能同时基于名人面孔视觉特征和语义信息进行精确的视觉统计学习; 基于正立名人面孔的视觉统计学习效果显著高于基于倒置名人面孔的视觉统计学习效果; 虽然基于视觉特征和语义信息的统计加工都具有一致的精确性, 但后者需要更多的加工时间。这提示：基于名人面孔视觉特征的视觉统计学习具有面孔特异性, 个体基于名人面孔视觉特征和语义信息的视觉统计学习过程是分离的, 统计运算发生于面孔特征加工完成之后。     

Visual statistical learning at basic and subordinate category levels in real-world images

Visual statistical learning (VSL) has been proposed as a powerful mechanism underlying the striking ability of human observers to handle complex visual environments. Previous studies have shown that VSL can occur when statistical information is embedded at multiple levels of abstraction, such as at semantically different category levels. In the present study, we further examined whether statistical regularities at a basic category level (e.g., a regular sequence of a bird, then a car, and then a dog) could influence the ability to extract statistical regularities at the subordinate level (e.g., a regular sequence of a parrot, then a sports car, and then an Eskimo dog). In the familiarization phase, participants were exposed to a stream of real-world images whose semantic categories had temporal regularities. Importantly, the temporal regularities existed at both the basic and subordinate levels, or the regularities existed at only the subordinate level, depending on the experimental condition. After completing the familiarization, participants performed a surprise two-alternative forced choice (2AFC) task for a familiarity judgment between two triplets in which the temporal regularities were either preserved or not preserved. Our results showed that the existence of statistical regularities at the basic level did not influence VSL at the subordinate level. The subsequent experiments showed these results consistently even when the basic-level categories had to be explicitly recognized and when the stimuli were not easily categorized at their subordinate level. Our results suggest that VSL is constrained to learn a particular level of patterns when patterns are presented across multiple levels.     

Constraint on the semantic flexibility in visual statistical learning

We examined whether the expression of visual statistical learning (VSL) is flexible at the superordinate-categorical level. In the familiarization phase, participants viewed a sequence of line drawings. In the test phase, participants observed two test sequences (statistically related triplets versus unrelated foils) that consisted of the same objects as those presented during the familiarization phase (the same condition) or different objects that shared the same categorical information with drawings during the familiarization (the different condition). They then decided whether the first or the second sequence was more familiar. The results of Experiment 1 showed greater familiarity above chance levels for statistically related triplets only in the same condition. In Experiment 2, even where the word stimuli representing each superordinate-level category were included in the test phase (the categorical condition), the results showed VSL only in the same condition. Our findings suggest that the semantic flexibility of VSL is limited to the basic-level category.     

Tasks determine what is learned in visual statistical learning

Visual statistical learning (VSL), the unsupervised learning of statistical contingencies across time and space, may play a key role in efficient and predictive encoding of the perceptual world. How VSL capabilities vary as a function of ongoing task demands is still poorly understood. VSL is modulated by selective attention and faces interference from some secondary tasks, but there is little evidence that the types of contingencies learned in VSL are sensitive to task demands. We found a powerful effect of task on what is learned in VSL. Participants first completed a visual familiarization task requiring judgments of face gender (female/male) or scene location (interior/exterior). Statistical regularities were embedded between stimulus pairs. During a surprise recognition phase, participants showed less recognition for pairs that had required a change in response key (e.g., female followed by male) or task (e.g., female followed by indoor) during familiarization. When familiarization required detection of “flicker” or “jiggle” events unrelated to image content, there was weaker, but uniform, VSL across pair types. These results suggest that simple task manipulations play a strong role in modulating the distribution of learning over different pair combinations. Such variations may arise from task and response conflict or because the manner in which images are processed is altered.     

Categorical implicit learning in real-world scenes: evidence from contextual cueing

The present study examined the extent to which learning mechanisms are deployed on semantic-categorical regularities during a visual searching within real-world scenes. The contextual cueing paradigm was used with photographs of indoor scenes in which the semantic category did or did not predict the target position on the screen. No evidence of a facilitation effect was observed in the predictive condition compared to the nonpredictive condition when participants were merely instructed to search for a target T or L (Experiment 1). However, a rapid contextual cueing effect occurred when each display containing the search target was preceded by a preview of the scene on which participants had to make a decision regarding the scene's category (Experiment 2). A follow-up explicit memory task indicated that this benefit resulted from implicit learning. Similar implicit contextual cueing effects were also obtained when the scene to categorize was different from the subsequent search scene (Experiment 3) and when a mere preview of the search scene preceded the visual searching (Experiment 4). These results suggested that if enhancing the processing of the scene was required with the present material, such implicit semantic learning can nevertheless take place when the category is task irrelevant.     

注意促进效应依赖于项目-背景的质心间距

近期研究者发现, 在某些条件下增加对第一任务的注意能够提高伴随发生的第二任务的成绩, 并将其命名为注意促进效应。研究者提出双任务交互模型对之进行解释, 认为该效应产生的必要条件是时间上的重叠, 而不受空间距离的影响。基于对这一观点的质疑, 本研究探究了检测项目与背景图片的质心间距对注意促进效应的影响。结果发现, 当目标项位于背景图片中央时(质心间距为0), 表现出注意促进效应; 而当二者分开一定的空间距离时, 出现了注意干扰/抑制效应。由此可见, 项目和背景的质心间距会对注意促进效应产生影响。     

The automaticity of visual statistical learning

The visual environment contains massive amounts of information involving the relations between objects in space and time, and recent studies of visual statistical learning (VSL) have suggested that this information can be automatically extracted by the visual system. The experiments reported in this article explore the automaticity of VSL in several ways, using both explicit familiarity and implicit response-time measures. The results demonstrate that (a) the input to VSL is gated by selective attention, (b) VSL is nevertheless an implicit process because it operates during a cover task and without awareness of the underlying statistical patterns, and (c) VSL constructs abstracted representations that are then invariant to changes in extraneous surface features. These results fuel the conclusion that VSL both is and is not automatic: It requires attention to select the relevant population of stimuli, but the resulting learning then occurs without intent or awareness.     

Across space and time: infants learn from backward and forward visual statistics

This study investigates whether infants are sensitive to backward and forward transitional probabilities within temporal and spatial visual streams. Two groups of 8‐month‐old infants were familiarized with an artificial grammar of shapes, comprising backward and forward base pairs (i.e. two shapes linked by strong backward or forward transitional probability) and part‐pairs (i.e. two shapes with weak transitional probabilities in both directions). One group viewed the continuous visual stream as a temporal sequence, while the other group viewed the same stream as a spatial array. Following familiarization, infants looked longer at test trials containing part‐pairs than base pairs, although they had appeared with equal frequency during familiarization. This pattern of looking time was evident for both forward and backward pairs, in both the temporal and spatial conditions. Further, differences in looking time to part‐pairs that were consistent or inconsistent with the predictive direction of the base pairs (forward or backward) indicated that infants were indeed sensitive to direction when presented with temporal sequences, but not when presented with spatial arrays. These results suggest that visual statistical learning is flexible in infancy and depends on the nature of visual input.     

Implicit scene learning is viewpoint dependent

When novel scenes are encoded, the representations of scene layout are generally viewpoint specific. Past studies of scene recognition have typically required subjects to explicitly study and encode novel scenes, but in everyday visual experience, it is possible that much scene learning occurs incidentally. Here, we examine whether implicitly encoded scene layouts are also viewpoint dependent. We used the contextual cuing paradigm, in which search for a target is facilitated by implicitly learned associations between target locations and novel spatial contexts (Chun & Jiang, 1998). This task was extended to naturalistic search arrays with apparent depth. To test viewpoint dependence, the viewpoint of the scenes was varied from training to testing. Contextual cuing and, hence, scene context learning decreased as the angular rotation from training viewpoint increased. This finding suggests that implicitly acquired representations of scene layout are viewpoint dependent.     

The role of familiarity in a face classification task using thatcherized faces

Two experiments are reported to test the proposition that facial familiarity influences processing on a face classification task. Thatcherization was used to generate distorted versions of familiar and unfamiliar individuals. Using both a 2AFC (which is “odd”?) task to pairs of images (Experiment 1) and an “odd/normal” task to single images (Experiment 2), results were consistent and indicated that familiarity with the target face facilitated the face classification decision. These results accord with the proposal that familiarity influences the early visual processing of faces. Results are evaluated with respect to four theoretical developments of Valentine's (1991) face-space model, and can be accommodated with the two models that assume familiarity to be encoded within a region of face space.     

空间工作记忆负载对真实场景情境提示效应的影响

重复的画面布局能够促进观察者对目标项的搜索 (情境提示效应)。本研究采用双任务范式,分别在视觉搜索任务的学习阶段 (实验2a) 和测验阶段 (实验2b) 加入空间工作记忆任务, 并与单任务基线 (实验1)进行比较, 考察空间工作记忆负载对真实场景搜索中情境线索学习和情境提示效应表达的影响。结果发现: 空间负载会增大学习阶段的情境提示效应量, 同时削弱测验阶段的情境提示效应量, 而不影响情境线索的外显提取。由此可见, 真实场景中情境线索的学习和提示效应的表达均会受到有限的工作记忆资源的影响, 但情境线索提取的外显性不变。     

Nonspatial attentional capture by previously rewarded scene semantics

Recent research has shown that reward influences visual perception and cognition in a way that is distinct from the well-documented goal-directed mechanisms. In the current study we explored how task-irrelevant stimulus-reward associations affect processing of stimuli when attention is constrained and reward no longer delivered. During a training phase, participants performed a choice game, exposing them to different reward schedules for different semantic categories of natural scene pictures. In a separate test session in which no additional reward was provided, the differentially rewarded scene categories were used as task-irrelevant non-targets in a rapid serial visual presentation (RSVP) task. Participants performed a detection task on a previously non-rewarded target category. Results show that participants' sensitivity index (d′) for target detection decreased as a function of whether the reward was coupled to the distractor category during training. The semantic category of natural scenes associated with high reward caused more interference in target detection than the semantic category associated with a low reward. The same was found when new, unseen distractor pictures of the same semantic categories were used. The present findings suggest that reward can be selectively associated with high level scene semantics. We argue that learned stimulus-reward associations persistently bias perceptual processing independently of spatial shifts in attention and the immediate prospect of reward.     

场景情境和目标模板在视觉搜索中的交互作用

以真实场景图像中的物体搜索为实验任务, 操纵场景情境和目标模板, 采用眼动技术将搜索过程分为起始阶段、扫描阶段和确认阶段, 考察场景情境和目标模板对视觉搜索过程的影响机制。结果发现, 场景情境和目标模板的作用方式及时间点不同, 二者交互影响搜索的正确率和反应时, 仅场景情境影响起始阶段的时间, 随后二者交互影响扫描阶段和确认阶段的时间及主要眼动指标。作者由此提出了场景情境和目标模板在视觉搜索中的交互作用模型。     

人工语法范式下的无意识知识探析

人工语法范式不仅是内隐学习领域广泛运用的范式,同时也是研究无意识知识的主要方法。文章通过对人工语法范式组成材料中的刺激频率、组块等方面进行深入探讨,不仅使人们对无意识知识有了更全面的认识,而且也有利于对内隐学习获得规则知识的假设提出更确定的回答;并通过对无意识知识的神经机制研究以及考察镜射规则学习过程的脑神经激活状况,获得了规则学习对应更为准确的脑神经活动,推动了人工语法范式下无意识知识的深入研究。     

The relationship between online visual representation of a scene and long-term scene memory

In 3 experiments the author investigated the relationship between the online visual representation of natural scenes and long-term visual memory. In a change detection task, a target object either changed or remained the same from an initial image of a natural scene to a test image. Two types of changes were possible: rotation in depth, or replacement by another object from the same basic-level category. Change detection during online scene viewing was compared with change detection after delay of 1 trial (Experiments 2A and 2B) until the end of the study session (Experiment 1) or 24 hr (Experiment 3). There was little or no decline in change detection performance from online viewing to a delay of 1 trial or delay until the end of the session, and change detection remained well above chance after 24 hr. These results demonstrate that long-term memory for visual detail in a scene is robust.     

Kompositionsbildung bei Symbolfolgen und Bediensequenzen: Empirische Befunde und die Theorie des „Competitive Chunking”

In the paradigm of artificial grammar learning subjects have to reproduce regularly structured sequences of symbols. In a subsequent and unexpected test, they have to discriminate sequences that correspond to those of thememorization task from sequences that do not. Discriminability of grammatical and nongrammatical strings is judged as evidence for unconscious learning. This effect has been explained by the creation of chunks: Memorization of strings is facilitated by composing elements to chunks. The hierarchical organization of these units allows the representation of grammatical strings by a few high level chunks. The fewer chunks are necessary to represent a given string the higher is its familiarity and the probability to be judged grammatical. For the incidental acquisition of knowledge about operating a device the creation of chunks could also be shown. In contrast to letter series, two peculiarities were found: (a) discriminability was rather low, (b) irregularities at the end of input sequences were most effective. These peculiarities dissappeared, if — similar to letter strings — the information about a single operation of a sequence was permanently available. In the present simulations it was investigated whether these effects are consistent with the theory of competitive chunking. The temporal grain within sequences was varied to investigate the impact of the availability of sequential information on discriminability. Three different modes of chunk creation were simulated in the test phase to investigate whether the creation of chunks is obligatory for perceptual integration or requires a memorization task. The variation of temporal grain had only a marginal impact on discriminability. The simulation of the empirical data required that grammatical chunks are created within the test phase. Implications of these findings are discussed.     

The Attentional Boost Effect: Transient increases in attention to one task enhance performance in a second task

Recent work on event perception suggests that perceptual processing increases when events change. An important question is how such changes influence the way other information is processed, particularly during dual-task performance. In this study, participants monitored a long series of distractor items for an occasional target as they simultaneously encoded unrelated background scenes. The appearance of an occasional target could have two opposite effects on the secondary task: It could draw attention away from the second task, or, as a change in the ongoing event, it could improve secondary task performance. Results were consistent with the second possibility. Memory for scenes presented simultaneously with the targets was better than memory for scenes that preceded or followed the targets. This effect was observed when the primary detection task involved visual feature oddball detection, auditory oddball detection, and visual color-shape conjunction detection. It was eliminated when the detection task was omitted, and when it required an arbitrary response mapping. The appearance of occasional, task-relevant events appears to trigger a temporal orienting response that facilitates processing of concurrently attended information (Attentional Boost Effect).     

Implicit learning increases preference for predictive visual display

We investigated whether implicit learning in a visual search task would influence preferences for visual stimuli. Participants performed a contextual cueing task in which they searched for visual targets, the locations of which were either predicted or not predicted by the positioning of distractors. The speed with which participants located the targets increased across trials more rapidly for predictive displays than for non-predictive displays, consistent with contextual cueing. Participants were subsequently asked to rate the "goodness" of visual displays. The rating results showed that they preferred predictive displays to both non-predictive and novel displays. The participants did not recognize predictive displays any more frequently than they did non-predictive or novel displays. These results suggest that contextual cueing occurred implicitly and that the implicit learning of visual layouts promotes a preference for visual layouts that are predictive of target location.     

Object-position binding in visual memory for natural scenes and object arrays

Nine experiments examined the means by which visual memory for individual objects is structured into a larger representation of a scene. Participants viewed images of natural scenes or object arrays in a change detection task requiring memory for the visual form of a single target object. In the test image, 2 properties of the stimulus were independently manipulated: the position of the target object and the spatial properties of the larger scene or array context. Memory performance was higher when the target object position remained the same from study to test. This same-position advantage was reduced or eliminated following contextual changes that disrupted the relative spatial relationships among contextual objects (context deletion, scrambling, and binding change) but was preserved following contextual change that did not disrupt relative spatial relationships (translation). Thus, episodic scene representations are formed through the binding of objects to scene locations, and object position is defined relative to a larger spatial representation coding the relative locations of contextual objects.     

Implicit learning of nonlocal musical rules: implicitly learning more than chunks

Dominant theories of implicit learning assume that implicit learning merely involves the learning of chunks of adjacent elements in a sequence. In the experiments presented here, participants implicitly learned a nonlocal rule, thus suggesting that implicit learning can go beyond the learning of chunks. Participants were exposed to a set of musical tunes that were all generated using a diatonic inversion. In the subsequent test phase, participants either classified test tunes as obeying a rule (direct test) or rated their liking for the tunes (indirect test). Both the direct and indirect tests were sensitive to knowledge of chunks. However, only the indirect test was sensitive to knowledge of the inversion rule. Furthermore, the indirect test was overall significantly more sensitive than the direct test, thus suggesting that knowledge of the inversion rule was below an objective threshold of awareness.