The Role of Spatial Attention in Nonconscious Processing: A Comparison of Face and Nonface Stimuli

ABSTRACT— Recent findings from the masked priming paradigm have revealed a surprising influence of higher-level cognitive systems (i.e., attention) on nonconscious cognitive processes. These data have effectively undermined the long-standing assumption in cognitive science that nonconscious processes are carried out independently of attention and have quickly led to the opposite view that attention is a prerequisite for nonconscious processes. Here we present evidence for a middle position by showing that the dependence of nonconscious processes on attention varies with the type of information to be processed. Specifically, we found that nonconsciously perceived faces engaged cognitive processes regardless of attention, whereas nonface stimuli engaged cognitive processes only when attended. These qualitatively different patterns suggest two distinct processing routes: one that is modulated by visual attention and one that is not.     

The effects of diffuse and distinct affect

In a series of suboptimal priming studies, it was shown that both affective and nonaffective reactions to a stimulus may occur without awareness. Moreover, it was demonstrated that affective information is detected earlier than nonaffective information. Therefore, early reactions to an affect-laden stimulus (e.g., a smiling man) are cognitively unappraised and thus diffuse (e.g., "positive"), whereas later affective reactions can be more specific and distinct (e.g., "a smiling man"). Through variations of prime exposure (extremely short, moderately short) the impact of early diffuse and late distinct affect on judgment was investigated. Findings show that distinctness (and prime-target similarity) is an essential determinant of whether the effect of affect is null, assimilation, or contrast. Furthermore, whether affect priming activates diffuse or distinct reactions is a matter of a fraction of seconds.     

Affective priming of nonaffective semantic categorization responses

Recent studies have shown that robust affective priming effects can be obtained when participants are required to categorize the targets on the basis of their valence, but not when participants are asked to categorize the targets on the basis of nonaffective features. On the basis of this pattern of results, it has been argued that affective priming is due to processes that operate at a response selection stage rather than to processes that operate at an encoding stage. We demonstrate (a) that affective priming of nonaffective semantic categorization responses can be obtained when participants assign attention to the affective stimulus dimension, and (b) that affective priming in the standard evaluative categorization task is strongly reduced when participants assign attention to nonaffective stimulus features. On the basis of these findings, we argue (a) that processes operating at an encoding stage do contribute to the affective priming effect, and (b) that automatic affective stimulus processing is reduced when participants selectively attend to nonaffective stimulus features.     

Stronger suboptimal than optimal affective priming?

The finding of stronger affective priming in less conscious (suboptimal) conditions than in fully conscious (optimal) conditions (S. T. Murphy & R. B. Zajonc, 1993) is theoretically important because it contradicts notions that emotions are primarily reflected by conscious states. In 2 experiments, this pattern of results was obtained. Happy and angry faces were presented both optimally and suboptimally and were masked by unknown ideographs. In Experiment 1, instructions for the conscious and less conscious affective priming conditions were matched, and affective ratings of ideographs were determined. In Experiment 2, a more implicit affective measure (facial electromyography of musculus zygomaticus major and musculus corrugator supercilii) served as the dependent variable. Stronger suboptimal than optimal affective priming was found in both experiments. It is concluded that stronger suboptimal than optimal processing is characteristic for affective processing and that it can also be found when instructions are matched and when a more implicit measure is assessed.     

Blind spots in the search for happiness: Implicit attitudes and nonverbal leakage predict affective forecasting errors

We investigated implicit knowledge and affective forecasting, reasoning that although conscious evaluations are available to people when predicting their future emotional responses, nonconscious evaluations are not. However, these automatically-activated evaluations should contribute to in-the-moment emotional experiences, and thus they should account for misforecasts (i.e., discrepancies between affective forecasts and actual experiences). We conducted two studies to explore affective misforecasts, using food items as stimuli. In Study 1, participants' implicit attitudes (but not their explicit attitudes) predicted misforecasts of food enjoyment, supporting the role of nonconscious evaluations in affective forecasting errors. In Study 2, we examined participants' facial expressions (another index of nonconscious evaluation) upon the presentation of food items, and we found that these nonverbal behaviors predicted affective misforecasts as well. In sum, although nonconscious evaluations are unavailable when anticipating the future, they may contribute to one's in-the-moment experiences and thus serve as blind spots in affective forecasting.     

Backward affective priming: Even when the prime is late, people still evaluate

It is well-established that affective stimuli can prime congruent evaluations if they precede the target within a short time interval, i.e., forward affective priming. The present research examines whether similar effects occur if affective primes succeed target presentation, i.e., backward affective priming. Experiments 1 found short-lived, yet reliable backward affective priming. Experiment 2 found parallel forward affective priming in the same paradigm. Experiment 3 found forward and backward affective priming in a within-subjects design. Comparison with neutral primes suggested that the observed effects were mainly due to interference. Backward affective priming is a robust phenomenon that may reflect a rapid and continuous evaluation of environmental stimuli.     

No evidence for subliminal affective priming with emotional facial expression primes

The present study investigated whether facial expressions of emotion presented outside consciousness awareness will elicit evaluative responses as assessed in affective priming. Participants were asked to evaluate pleasant and unpleasant target words that were preceded by masked or unmasked schematic (Experiment 1) or photographic faces (Experiments 1 and 2) with happy or angry expressions. They were either required to perform the target evaluation only or to perform the target evaluation and to name the emotion expressed by the face prime. Prime-target interval was 300 ms in Experiment 1 and 80 ms in Experiment 2. Naming performance confirmed the effectiveness of the masking procedure. Affective priming was evident after unmasked primes in tasks that required naming of the facial expressions for schematic and photographic faces and after unmasked primes in tasks that did not require naming for photographic faces. No affective priming was found after masked primes. The present study failed to provide evidence for affective priming with masked face primes, however, it indicates that voluntary attention to the primes enhances affective priming.     

Nervous Instability and Genius: Military and Political Leaders

Participants (N = 106) performed an affective priming task with facial primes that varied in their skin tone and facial physiognomy, and, which were presented either in color or in gray-scale. Participants' racial evaluations were more positive for Eurocentric than for Afrocentric physiognomy faces. Light skin tone faces were evaluated more positively than dark skin tone faces, but the magnitude of this effect depended on the mode of color presentation. The results suggest that in affective priming tasks, faces might not be processed holistically, and instead, visual features of facial priming stimuli independently affect implicit evaluations.     

时间间隔对面部表情唤醒度阈下情绪启动的影响

采用3×4混合实验设计,研究了启动刺激与靶刺激的时间间隔对面部表情唤醒度阈下情绪启动效应的影响,实验因素为启动刺激的唤醒度和时间间隔。结果发现,当时间间隔为200ms、300ms、500ms时,出现了阈下情绪启动效应,时间间隔为700ms时,启动效应消失。上述结果表明阈下情绪启动效应可在唤醒度维度上实现,但此效应只能在启动刺激与靶刺激间隔时间较短的情况下出现。     

记忆编码中目标与背景的情绪一致性对记忆提取的影响

摘 要 本研究将经典情绪启动范式和学习-再认范式相结合,探讨学习时启动与目标的情绪一致性对目标再认的影响。在记忆编码阶段,以情绪面孔图片为启动刺激、一般情绪图片为目标刺激,要求被试对目标图片的效价进行判断;在提取阶段向被试呈现一般情绪图片,要求被试判断是否在前一阶段见过。结果表明,编码阶段的加工背景对记忆提取产生了显著影响。一致启动促进了认知加工与记忆编码,提高了再认正确率。ERP结果也表明,在目标刺激呈现后300-500ms,编码时的情绪一致性对再认阶段消极目标诱发的ERP产生了显著影响。     

Processing of unattended emotional visual scenes

Prime pictures of emotional scenes appeared in parafoveal vision, followed by probe pictures either congruent or incongruent in affective valence. Participants responded whether the probe was pleasant or unpleasant (or whether it portrayed people or animals). Shorter latencies for congruent than for incongruent prime-probe pairs revealed affective priming. This occurred even when visual attention was focused on a concurrent verbal task and when foveal gaze-contingent masking prevented overt attention to the primes but only if these had been preexposed and appeared in the left visual field. The preexposure and laterality patterns were different for affective priming and semantic category priming. Affective priming was independent of the nature of the task (i.e., affective or category judgment), whereas semantic priming was not. The authors conclude that affective processing occurs without overt attention--although it is dependent on resources available for covert attention--and that prior experience of the stimulus is required and right-hemisphere dominance is involved.     

Affect of the unconscious: Visually suppressed angry faces modulate our decisions

Emotional and affective processing imposes itself over cognitive processes and modulates our perception of the surrounding environment. In two experiments, we addressed the issue of whether nonconscious processing of affect can take place even under deep states of unawareness, such as those induced by interocular suppression techniques, and can elicit an affective response that can influence our understanding of the surrounding environment. In Experiment 1, participants judged the likeability of an unfamiliar item—a Chinese character—that was preceded by a face expressing a particular emotion (either happy or angry). The face was rendered invisible through an interocular suppression technique (continuous flash suppression; CFS). In Experiment 2, backward masking (BM), a less robust masking technique, was used to render the facial expressions invisible. We found that despite equivalent phenomenological suppression of the visual primes under CFS and BM, different patterns of affective processing were obtained with the two masking techniques. Under BM, nonconscious affective priming was obtained for both happy and angry invisible facial expressions. However, under CFS, nonconscious affective priming was obtained only for angry facial expressions. We discuss an interpretation of this dissociation between affective processing and visual masking techniques in terms of distinct routes from the retina to the amygdala.     

Priming in interpersonal contexts: implications for affect and behavior

Priming stereotypes can lead to a variety of behavioral outcomes, including assimilation, contrast, and response behaviors. However, the conditions that give rise to each of these outcomes are unspecified. Furthermore, theoretical accounts posit that prime-to-behavior effects are either direct (i.e., unmediated) or mediated by cognitive processes, whereas the role of affective processes has been largely unexplored. The present research directly investigated both of these issues. Three experiments demonstrated that priming a threatening social group ("hoodies") influences both affect and behavior in an interpersonal context. Hoodie priming produced both behavioral avoidance and several affective changes (including social apprehension, threat sensitivity, and self-reported anxiety and hostility). Importantly, avoidance following hoodie priming was mediated by anxiety and occurred only under conditions of other- (but not self-) focus. These results highlight multiple routes through which primes influence affect and behavior, and suggest that attention to self or others determine the nature of priming effects.     

Not Only Whites: Racial Priming Effect for Black Faces in Black People

Black people are widely negatively stereotyped. The presence of unconscious stereotypes can be effectively assessed with the administration of “racial priming tasks.” An ethnically diverse group was subjected to a priming paradigm to test whether racial cues could bias the identification of target objects. Participants were asked to categorize objects (either as dangerous or nondangerous) after the presentation of Black/White faces as primes. Results show that both Black and White participants were faster in categorizing dangerous objects when primed with Black faces compared to the control condition (i.e., scrambled faces). One possible explanation for this effect is that Black faces are generally associated with a feeling of danger, which ultimately leads to faster responses.     

Goal relevance moderates evaluative conditioning effects

An important process by which preferences emerge is evaluative conditioning, defined as a change in the evaluation of a stimulus by pairing it repeatedly and consistently with an affective stimulus. The current research focuses on the role of motivation in this learning process. Specifically, it was investigated whether a conditioning procedure that is relevant to an individual's current goals is more effective than an irrelevant procedure. To this end, beverages were conditioned with either disgusted faces (relevant) or fearful faces (irrelevant). The results showed that thirsty(rather than non-thirsty) participants’ choice and evaluation of beverages were influenced by pairing beverages with disgust but not with fear. As similar results were obtained under optimal and suboptimal presentation of the conditioned stimuli, it is suggested that goals can affect automatic, associative learning, adding to the emerging body of research demonstrating that goals unconsciously affect evaluative processes.     

The perceptual determinants of person construal: reopening the social-cognitive toolbox

Guided by a heuristic account of social-cognitive functioning, researchers have attempted to identify the cognitive benefits that derive from a categorical approach to person construal. While revealing, this work has overlooked the fact that, prior to the application of categorical thinking as an economizing mental tool, perceivers must first extract category-triggering information from available stimulus cues. It is possible, therefore, that basic perceptual processes may also contribute to people's propensity to view others in a category-based manner. This possibility was explored in 3 experiments in which the authors investigated the ease with which perceivers can extract categorical and identity-based knowledge from faces under both optimal and suboptimal (i.e., inverted faces, blurred faces, rapidly presented faces) processing conditions. The results confirmed that categorical knowledge is extracted from faces more efficiently than identity-related knowledge, a finding that underscores the importance of perceptual operations in the generation of categorical thinking.     

Evidence that nonconscious processes are sufficient to produce false memories

Are nonconscious processes sufficient to cause false memories of a nonstudied event? To investigate this issue, we controlled and measured conscious processing in the DRM task, in which studying associates (e.g., bed, rest, awake...) causes false memories of nonstudied associates (e.g., sleep). During the study phase, subjects studied visually masked associates at extremely rapid rates, followed by immediate recall. After this initial phase, nonstudied test words were rapidly presented for perceptual identification, followed by recognition memory judgments. On the perceptual identification task, we found significant priming of nonstudied associates, relative to control words. We also found significant false recognition of these nonstudied associates, even when subjects did not recall this word at study or identify it at test, indicating that nonconscious processes can cause false recognition. These recognition effects were found immediately after studying each list of associates, but not on a delayed test that occurred after the presentation of several intervening lists. Nonconscious processes are sufficient to cause this memory illusion on immediate tests, but may be insufficient for more vivid and lasting false memories.     

阈下安全启动改善非安全依恋女性的注意加工

研究采用掩蔽启动范式，结合事件相关电位技术，考察阈下安全启动在非安全依恋女性对婴儿面孔注意加工上的改善效应。行为指标上，悲伤程度评分和反应时结果均表明了安全启动的改善作用。ERP结果上，在早期注意加工阶段，阈下安全启动比中性启动诱发了依恋焦虑和依恋回避女性对婴儿面孔表情更大的N1波幅以及更优的P2潜伏期，在晚期控制注意加工相关的P3波幅上同样发现了类似的改善效应。研究结果表明阈下安全启动能够提升非安全依恋女性对婴儿面孔的知觉敏感性，改善非安全依恋女性注意加工缺陷，且这种改善效应不仅仅作用于早期注意加工阶段而且还可以扩展到个体有意识的晚期控制加工阶段。     

Interaction of prime and target in the subliminal affective priming effect

It has been found that an emotional stimulus such as a facial expression presented subliminally can affect subsequent information processing and behavior, usually by shifting evaluation of a subsequent stimulus to a valence congruent with the previous stimulus. This phenomenon is called subliminal affective priming. The present study was conducted to replicate and expand previous findings by investigating interaction of primes and targets in the affective priming effect. Two conditions were used. Prime (subliminal presentation 35 msec.) of an angry face of a woman and a No Prime control condition. Just after presentation of the prime, an ambiguous angry face or an emotionally neutral face was presented above the threshold of awareness (500 msec.). 12 female undergraduate women judged categories of facial expressions (Anger, Neutral, or Happiness) for the target faces. Analysis indicated that the Anger primes significantly facilitated judgment of anger for the ambiguous angry faces; however, the priming effect of the Anger primes was not observed for neutral faces. Consequently, the present finding suggested that a subliminal affective priming effect should be more prominent when affective valence of primes and targets is congruent.     

The influence of alcohol expectancy priming and mood manipulation on subsequent alcohol consumption

Studies showing that verbal priming can implicitly affect alcohol consumption have been used to support cognitive models of expectancies. However, because expectancy words reflect affective states as well as drinking outcomes, mediation through an affective pathway remains theoretically plausible (i.e., such words inadvertently may affect mood, which in turn influences drinking). The primary pathway was identified (and expectancy theory was tested) by comparing memory priming (using alcohol expectancy or neutral words) with mood induction (using positive or neutral music); an unrelated experiment paradigm allowed the priming manipulation to implicitly affect drinking. Men in the alcohol priming group drank significantly more than men in each of the other conditions, and, consistent with theory, men with histories of heavier drinking drank the most when primed with alcohol expectancies, indicating that expectancies can function as automatic memory processes.