颜色特征加工任务间的注意瞬脱研究

本研究以两个实验对颜色特征加工任务间的注意瞬脱效应进行探讨。实验一要求被试对首先呈现的两个色块(记忆项)与随后呈现的两个色块(检测项)是否相同进行比较。结果发现,在记忆项与检测项的SOA为220ms的条件下,记忆项加工对认知资源的持续占用使检测项的加工绩效下降。实验二含两个需相继执行的任务(T1和T2),二者均为比较同时呈现在屏幕左右两侧的两色块颜色是否相同。结果发现,对颜色特征的觉察即可产生注意瞬脱效应,其大小及时程与经典的采用字母识别任务的研究获得的注意瞬脱效应相当。上述结果表明,特征搜索的完成需有限认知资源的参与。然而,注意瞬脱过程中,特征加工与需对知觉对象细节信息进行提取的辨别任务(如字母辨别任务)在消耗认知资源的量上并无差别。     

Are more items identified than can be reported?

Subjects are typically able to report only about four items from a many-item array presented tachistoscopically (full-report span). Current models of visual information processing disagree as to whether the limiting process is best represented as identification or as short-term memory. Estes and Taylor have argued that the number of items identified is up to twice the full-report span and, hence, that memory limits report. Experiment 1 here used a memory-probe method which showed that when no position report is required the large number of items that were identified in the Estes and Taylor paradigm is not greater than the number in a posticonic memory. Experiment 2 indicated that when position report is required the number of items identified (with correct position) does not exceed the number which can be reproduced in full report. These results support models in which memory is entailed by identification either as an aspect of the identification process or as a separate stage.     

Capacity limitations in visual word processing

The ability of subjects to process English words in a spatially parallel manner was examined in several redundant-target detection tasks. When redundant targets were identical in a given display, processing limitations were evident in a task that required subjects to make semantic categorizations of words. However, parallel processing of identical redundant target words was exhibited in a lexical decision task that required a structural analysis of letter strings, but not an analysis of word meaning. The difference in performance in the two tasks suggests that the capacity for semantic processing is limited. Analyses designed to examine whether the redundancy gain in Experiment 2 could be attributed to limited capacity processing in conjunction with positional preferences provided evidence against this possibility. In addition, these analyses suggested that the processing times for the redundant targets in Experiment 2 might be positively correlated. In the third and fourth experiments, the redundant-target displays contained two different words. Processing interference, in the form of a redundancy loss, was evident in the lexical decision task, but not in the semantic categorization task, confirming a difference in the mode of processing between the two tasks. The results provide evidence against the unlimited-capacity, parallel processing hypothesis of late selection theories of attention.     

Memory for things forgotten.

As previous research has shown, items not recalled on an initial memory task are not simply forgotten. Often, some can be recalled on a later, second task. Further, subjects can generally predict, in terms of feeling-of-knowing (FOK) ratings, which items will be subsequently recalled. Two experiments were carried out to assess both second-task performance and FOK accuracy for unrecalled items as a function of two factors, encoding manipulations (levels of processing in Experiment 1, study time in Experiment 2) and the nature of the second task (explicit or implicit cued stem completion). Results indicate that although levels of processing affected explicit second-task performance more than implicit second-task performance, it increased FOK accuracy in both types of tasks. Study time, however, affected FOK accuracy only in the explicit second task. Apparently, only when subjects were able to do some elaborative processing on the items did their FOK ratings reflect information relating to factors that drive performance on implicit tasks.     

Task-dependent costs in processing two simultaneous auditory stimuli

A listener presented with two speech signals must at times sacrifice the processing of one signal in order to understand the other. This study was designed to distinguish costs related to interference from a second signal (selective attention) from costs related to performing two tasks simultaneously (divided attention). Listeners presented with two processed speech-in-noise stimuli, one to each ear, either (1) identified keywords in both or (2) identified keywords in one and detected the presence of speech in the other. Listeners either knew which ear to report in advance (single task) or were cued afterward (partial-report dual task). When the dual task required two identification judgments, performance suffered relative to the single-task condition (as measured by percent correct judgments). Two different tasks (identification for one stimulus and detection for the other) resulted in much smaller reductions in performance when the cue came afterward. We concluded that the degree to which listeners can simultaneously process dichotic speech stimuli seems to depend not only on the amount of interference between the two stimuli, but also on whether there is competition for limited processing resources. We suggest several specific hypotheses as to the structural mechanisms that could constitute these limited resources.     

Stimulus similarity decrements in children's working memory span

Two experiments investigated the impact of the relationship between processing and storage stimuli on the working memory span task performance of children aged 7 and 9 years of age. In Experiment 1, two types of span task were administered (sentence span and operation span), and participants were required to recall either the products of the processing task (sentence-final word, arithmetic total) or a word or digit unrelated to the processing task. Experiment 2 contrasted sentence span and operation span combined with storage of either words or digits, in tasks in which the item to be remembered was not a direct product of the processing task in either condition. In both experiments, memory span was significantly greater when the items to be recalled belonged to a different stimulus category from the material that was processed, so that in sentence span tasks, number recall was superior to word recall, and in operation span tasks, word recall was superior to number recall. Explanations of these findings in terms of similarity-based interference and response competition in working memory are discussed.     

Effect of task, selection set, and dispersion of attention on visual identification time

Schioldborg, P., Paus, E. & Myhre, G. Effect of task, selection set, and dispersion of attention on visual identification time. Scand. J. Psychol., 1973, 14, 195–198. Letters and digits were presented in rows of one, two, or three, and the time required for identifying their position, colour, class, or names recorded for three subjects. The identification tasks were performed under three different conditions of preparatory set, making use of position, colour, and class as selecting attributes. (1) Under each selection set, only the identification of letters and digits as such required more time with increasing number of items, indicating limiting conditions for a "constancy" model of attention. (2) For all identification tasks, selection procured by class yielded longer identification time than selection by position or colour, suggesting different levels of complexity in information processing. (3) Identification of class under a position set, or position under a class set, required less time than the corresponding combinations with colour in place of position, suggesting that analysis of form and position relate basically to the same processes.     

Simultaneous auditory and tactile information processing

Subjects were required to perform perceptual tasks when stimuli were presented simultaneously in the auditory and tactile modalities and when they were presented in one of the modalities alone. The results indicated that when the demands on cognitive processes are small, auditory and tactile stimuli presented simultaneously can be processed as well as when stimuli are presented in only one modality. In a task which required a large amount of cognitive processing, it became difficult for subjects to maintain high levels of performance in both modalities and the distribution of attention became an important determinant of performance. The data were consistent with a theory that cognitive, but not perceptual, processing is disrupted when subjects have difficulty performing two perceptual tasks simultaneously.     

Localized attentional interference affects object individuation, not feature detection

Modern theorists conceptualize visual selective attention as a competition between object representations for the control of extrastriate receptive fields, an account supported by the finding that attentional selection of one stimulus can degrade processing of nearby stimuli. In the present study the conditions that produce reciprocal interference between attended stimuli are examined. Each display contained either no, one, or two feature-defined target items among an array of homogeneous distractors. Observers performed two tasks, feature detection and object individuation. The feature-detection task required observers to determine if any targets were present within the display. The object-individuation task required observers to determine if the number of targets was exactly two. Spatially mediated interference between target pairs occurred in the object-individuation task, but had no effect on feature detection. Results suggest that localized interference between attended stimuli occurs only when observers are required to resolve the features of individual objects, consistent with the competitive interaction models of attention.     

ERP evidence for task modulations on face perceptual processing at different spatial scales

Does the perceptual processing of faces flexibly adapt to the requirements of the categorization task at hand, or does it operate independently of this cognitive context? Behavioral studies have shown that the fine and coarse spatial scales of a face are differentially processed depending on the categorization task performed, thus suggesting that the latter can influence stimulus perception. Here, we investigated the time course of these task influences on perceptual processing by examining the visual N170 face‐sensitive Event‐Related Potential (ERP), while observers categorized faces for their gender and familiarity. Stimuli were full spectrum, or filtered versions that preserved either coarse or fine scale information of the faces. Behavioral results replicated previous findings of a differential processing of coarse and fine spatial scales across tasks. In addition, the N170 amplitude was larger in the Gender task as compared to the Familiarity task for LSF faces exclusively, thus showing that task demands differentially modulated the spatial scale processing on faces. These results suggest that the diagnosticity of scale‐specific cues in categorization tasks can modulate face processing.     

On the nonautomaticity of “automatic” activation: Evidence of selective seeing

Early perceptual selection refers to a sequence of perceptual processing in which attentional selection of stimuli occurs before perceptual processing is complete. By contrast, late perceptual selection refers to a sequence in which all stimuli receive complete perceptual processing before selection takes place. An attempt was made to determine if early selection is possible. Three experiments were conducted in which subjects were presented with arrays containing a variable number of red items and a variable number of black items; all array items were randomly positioned around the circumference of an imaginary circle. The subjects task was to report the number of red items. Response time increased with the number of red items, but was essentially independent of the number of black items. The nature of the red and black items was also varied. When the to-be-attended red items were given “Stroop-like” quality (the symbols that were used were directly inconsistent with the correct response for that trial), mean reaction time was increased compared to a baseline condition; when the to-be-ignored black items were given “Stroop-like” quality, mean reaction time was unaffected. These results imply that the relevant (red) and irrelevant (black) items were processed differentially. We conclude that early selection is possible; late-selection models are not supported.     

On the differential nature of implicit and explicit memory

In this article, we report two experiments that provide further evidence concerning the differential nature of implicit and explicit memory. In Experiment 1, subjects first undertook a sentenceverification task. While carrying out this task, half of the subjects were also required to carry out a secondary processing task involving tone monitoring. Twenty-four hours later, the subjects’ memory for target items in the sentence-verification task was tested explicitly by means of a recognition task and implicitly by examining the extent to which the items primed fragment completion. Recognition performance was significantly impaired by the imposition of secondary processing demands during the original learning phase. In contrast, fragment completion was completely unaffected by this additional processing, even though substantial priming was observed. In Experiment 2, we examined whether priming in fragment completion is influenced by the nature of repetition during initial learning. Subjects studied a list of target items that were each repeated twice. Halfthe items were repeatedimmediately (lag 0) and halfwere repeated after six intervening items (lag 6). Memory for the itemswas assessed by recognition and by priming in fragment completion. Recognition was affected by lag, with lag 6 items being recognized better than lag 0 items. However, although significant priming was obtained, the extent of this priming was uninfluenced by lag. These data indicate two additional dimensions along which implicit and explicit memory differ and, furthermore, they support recent conceptualizations of processing differences underlying these two forms of memory.     

The effect of semantic distance in yes/no and go/no-go semantic categorization tasks

The effect of semantic distance (Lund & Burgess, 1996) was examined in three semantic categorization experiments. Experiment 1, a yes/no task that required participants to make animal/nonanimal judgments by responding to both sets of stimuli (Forster & Shen, 1996), revealed no effect of semantic distance. Experiment 2, a go/no-go task that required participants to respond to only the experimental (i.e., nonanimal) items, revealed a large effect of semantic distance. In addition, response latencies were longer and error rates were lower to the experimental items in Experiment 2 than to those in Experiment 1. These findings were replicated in Experiment 3, in which semantic distance and task condition were manipulated within subjects. We conclude that these results are consistent with (1) the view that the go/no-go tasks elicited more extensive processing of the experimental items and (2) a connectionist account of semantic activation, whereby processing is facilitated by the presence of semantic neighbors.     

Parallel processing of position and form information in young children

Young children and adults were compared in their processing of position and form information when only one type of information was processed and when both types of information were processed. For adults, position information in both the single and combined tasks showed a linear increase in report accuracy with increasing duration. For children, this linear increase was found only in the single task, at longer durations, resulting in a loss of parity across tasks for position information among children. No loss of parity was found for form information for either age group. The children’s loss of parity in processing position information when combined with form information replicates their previously demonstrated inability to process multiple-form arrays using a parallel independent strategy.     

Effects of Perceptual and Conceptual Processing on Memory for Words and Voice: Different Patterns for Young and Old

In two experiments younger and older adults listened to a list of words presented auditorily by two speakers. The subjects processed each word either perceptually (voice judgements) or conceptually (pleasantness judgements), and were then given memory tasks for the words and the presenting voice. In the word-recognition task the two age groups benefited equally from conceptual as opposed to perceptual processing. In the voice memory task, however, conceptual processing improved performance relative to perceptual processing in the younger subjects (significantly so in Experiment 1), but conceptual processing was associated with decreased performance in the older group (significantly so in Experiment 2). These results suggest that whereas older subjects exhibit a trade-off in memory for item and attribute information, younger subjects exhibit a pattern of support, in which conceptual processing benefits memory for both items and their attributes.     

Visual search for positional relationships between pattern elements

The purpose of these experiments was to illustrate how a search for positional relationships between the elements in a stimulus pattern is effortful and serial, whereas a search for pattern elements (without requiring any positional information) takes place rapidly and in parallel. In all three experiments of this study, the target and distractor patterns consisted of two vertical line segments. In the experiment concerning the search for positional relationships between pattern elements, one of the line segments in a line pair had a gap, and the observer's task was to indicate whether the positional order of the two lines was identical in all the line pairs of the display, or whether the line segments were in a mirror-image order in one line pair (the target). In the two experiments concerning the search for pattern elements (no positional information was required), the observer's task was to look for a line pair with one gap line (the target) among line pairs containing two broken lines or among line pairs with unbroken lines. In all three tasks, the reaction time for a correct target detection was measured. The results showed that the search in the first task was highly serial, and in the second and third tasks of "feature" searches, the search time was nearly independent of the number of distractor pairs. It is suggested that this dissociation may be interpreted in the context of the quality of information processing in extrafoveal vision, i. e. the elements of a stimulus pattern can be clearly visible outside the fovea, but it is not possible to perceive accurately the positional relationships between them.     

Interfering with memory for faces: The cost of doing two things at once

We inferred the processes critical for episodic retrieval of faces by measuring susceptibility to memory interference from different distracting tasks. Experiment 1 examined recognition of studied faces under full attention (FA) or each of two divided attention (DA) conditions requiring concurrent decisions to auditorily presented letters. Memory was disrupted in both DA relative to FA conditions, a result contrary to a material-specific account of interference effects. Experiment 2 investigated whether the magnitude of interference depended on competition between concurrent tasks for common processing resources. Studied faces were presented either upright (configurally processed) or inverted (featurally processed). Recognition was completed under FA, or DA with one of two face-based distracting tasks requiring either featural or configural processing. We found an interaction: memory for upright faces was lower under DA when the distracting task required configural than featural processing, while the reverse was true for memory of inverted faces. Across experiments, the magnitude of memory interference was similar (a 19% or 20% decline from FA) regardless of whether the materials in the distracting task overlapped with the to-be-remembered information. Importantly, interference was significantly larger (42%) when the processing demands of the distracting and target retrieval task overlapped, suggesting a processing-specific account of memory interference.     

Interference in visual perception by verbal and spatial cognitive activity

In two experiments we tested the hypothesis that cognitive processing based on spatial imagery produces more deterioration of visual perception than cognitive processing based on verbal codes. So, we studied the effect on visual perception of two cognitive tasks, one of spatial imagery and the other a verbal task. In the first one, with 30 participants, we analyzed the mental load and ocular behaviors in both cognitive tasks. In the second experiment, with 29 participants, we studied the effect of both tasks on a visual search task, using a dual-task experimental paradigm. The verbal task presented higher mental load than the imagery task when both tasks were carried out with visual search task, and there was more deterioration in stimulus detection with the verbal task. We can conclude that: (1) cognitive tasks produce important deterioration in the capacities of visual search and identification of stimuli; (2) this deterioration has two components: (a) an inefficient search, associated with alterations of the gaze patterns while performing cognitive tasks, and (b) a general interference, nonspecific to spatial codes, in the process of identification of looked-at stimuli; (3) this cognitive interference is related to the mental load or effort required by the cognitive task.     

Functional heterogeneity of inferior frontal gyrus is shaped by linguistic experience

A crosslinguistic, positron emission tomography (PET) study was conducted to determine the influence of linguistic experience on the perception of segmental (consonants and vowels) and suprasegmental (tones) information. Chinese and English subjects (10 per group) were presented binaurally with lists consisting of five Chinese monosyllabic morphemes (speech) or low-pass-filtered versions of the same stimuli (nonspeech). The first and last items were targeted for comparison; the time interval between target tones was filled with irrelevant distractor tones. A speeded-response, selective attention paradigm required subjects to make discrimination judgments of the target items while ignoring intervening distractor tones. PET scans were acquired for five tasks presented twice: one passive listening to pitch (nonspeech) and four active (speech = consonant, vowel, and tone; nonspeech = pitch). Significant regional changes in blood flow were identified from comparisons of group-averaged images of active tasks relative to passive listening. Chinese subjects show increased activity in left premotor cortex, pars opercularis, and pars triangularis across the four tasks. English subjects, on the other hand, show increased activity in left inferior frontal gyrus regions only in the vowel task and in right inferior frontal gyrus regions in the pitch task. Findings suggest that functional circuits engaged in speech perception depend on linguistic experience. All linguistic information signaled by prosodic cues engages left-hemisphere mechanisms. Storage and executive processes of working memory that are implicated in phonological processing are mediated in discrete regions of the left frontal lobe.     

概念内隐记忆中的注意促进效应

Swallow和Jiang (2010)最早发现, 编码时的目标探测会促进同时呈现的背景信息在随后记忆测验中的表现, 并将这一现象称为注意促进效应(Attentional Boost Effect, ABE)。随后研究发现这一现象并不会出现在概念内隐测验中, 由此提出目标探测主要促进的是背景信息的知觉加工, 而非语义加工。本研究通过3个实验, 操纵了对背景信息的编码加工类型(知觉加工或概念加工)。结果发现, 当与目标探测同时进行的是对背景信息的概念加工任务, 则ABE会出现在随后的概念内隐测验中。反之, 当对背景信息进行的是知觉加工任务时, 则ABE会出现在随后的知觉内隐测验而不是概念内隐测验中。这些结果表明, 目标探测既可能促进背景信息的知觉加工, 也可能促进背景信息的语义加工, 但只有在目标探测下背景信息的编码加工与随后内隐测验中所依赖的提取加工具有一致性, 才会产生ABE。