Accuracy of familiarity decisions to famous faces perceived without awareness depends on attitude to the target person and on response latency

Stone and Valentine (2004) presented masked 17 ms faces in simultaneous pairs of one famous and one unfamiliar face. Accuracy in selecting the famous face was higher when the famous person was regarded as "good" or liked than when regarded as "evil" or disliked. Experiment 1 attempted to replicate this phenomenon, but produced a different pattern of results. Experiment 2 investigated alternative explanations and found evidence supporting only the effect of response latency: responses made soon after stimulus onset were more accurate to liked than to disliked faces, whereas responses made after a longer delay were equally accurate to disliked faces. It appears that the effect of negative valence was corrected within the space of a few hundred milliseconds. Experiment 3, using an affective priming paradigm, supported the concept that an early-arising effect of valence is corrected if it is misleading to the directed task.     

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.     

Make the manikin move: Symbolic approach–avoidance responses affect implicit and explicit face evaluations

The present research aimed to replicate and extend findings of Huijding, Muris, Lester, Field, and Joosse (2011), investigating whether symbolic approach–avoidance responses can induce implicit and explicit evaluation biases. Faces with a neutral expression were shown on a computer screen, and participants were instructed to repeatedly move a manikin towards some faces (approach) and away from other faces (avoidance). An affective priming task and a face rating task were used to assess training-compatible differences in implicit and explicit face evaluations, respectively. Results showed that the manikin training was successful: The priming task revealed more positive implicit evaluations of approached than avoided faces, and approached faces were rated more positively than avoided ones in the face rating task. These findings replicate those of Huijding and colleagues by demonstrating training effects on explicit evaluations, and they extend them by demonstrating effects on implicit evaluations.     

Cross-domain semantic priming in normal subjects and a prosopagnosic patient

Cross-domain semantic priming of person recognition (from face primes to name targets at 500msecs SOA) is investigated in normal subjects and a brain-injured patient (PH) with a very severe impairment of overt face recognition ability. Experiment 1 demonstrates equivalent semantic priming effects for normal subjects from face primes to name targets (cross-domain priming) and from name primes to name targets (within-domain priming). Experiment 2 demonstrates cross-domain semantic priming effects from face primes that PH cannot recognize overtly. Experiment 3 shows that cross-domain semantic priming effects can be found for normal subjects when target names are repeated across all conditions. This (repeated targets) method is then used in Experiment 4 to establish that PH shows equivalent semantic priming to normal subjects from face primes which he is very poor at identifying overtly and from name primes which he can identify overtly. These findings demonstrate that automatic aspects of face recognition can remain intact even when all sense of overt recognition has been lost.     

Better the devil you know? Nonconscious processing of identity and affect of famous faces

The nonconscious recognition of facial identity was investigated in two experiments featuring brief (17-msec) masked stimulus presentation to prevent conscious recognition. Faces were presented in simultaneous pairs of one famous face and one unfamiliar face, and participants attempted to select the famous face. Subsequently, participants rated the famous persons as ”good“ or ”evil“ (Experiment 1) or liked or disliked (Experiment 2). In Experiments 1 and 2, responses were less accurate to faces of persons rated evil/disliked than to faces of persons rated good/liked, and faces of persons rated evil/disliked were selected significantly below chance. Experiment 2 showed the effect in a within-items analysis: A famous face was selected less often by participants who disliked the person than by participants who liked the person, and the former were selected below chance accuracy. The within-items analysis rules out possible confounding factors based on variations in physical characteristics of the stimulus faces and confirms that the effects are due to participants’ attitudes toward the famous persons. The results suggest that facial identity is recognized preconsciously, and that responses may be based on affect rather than familiarity.     

Priming effects on the N400 in the affective priming paradigm with facial expressions of emotion

We studied the effect of facial expression primes on the evaluation of target words through a variant of the affective priming paradigm. In order to make the affective valence of the faces irrelevant to the task, the participants were assigned a double prime–target task in which they were unpredictably asked either to identify the gender of the face or to evaluate whether the word was pleasant or unpleasant. Behavioral and electrophysiological (event-related potential, or ERP) indices of affective priming were analyzed. Temporal and spatial versions of principal components analyses were used to detect and quantify those ERP components associated with affective priming. Although no significant behavioral priming was observed, electrophysiological indices showed a reverse priming effect, in the sense that the amplitude of the N400 was higher in response to congruent than to incongruent negative words. Moreover, a late positive potential (LPP), peaking around 700 ms, was sensitive to affective valence but not to prime–target congruency. This pattern of results is consistent with previous accounts of ERP effects in the affective priming paradigm that have linked the LPP with evaluative priming and the N400 with semantic priming. Our proposed explanation of the N400 priming effects obtained in the present study is based on two assumptions: a double check of affective stimuli in terms of valence and specific emotion content, and the differential specificities of facial expressions of positive and negative emotions.     

The locus of semantic priming effects in person recognition

Semantic priming in person recognition has been studied extensively. In a typical experiment, participants are asked to make a familiarity decision to target items that have been immediately preceded by related or unrelated primes. Facilitation is usually observed from related primes, and this priming is equivalent across stimulus domains (i.e., faces and names prime one another equally). Structural models of face recognition (e.g., IAC: Burton, Bruce, & Johnston, 1990) accommodate these effects by proposing a level of person identity nodes (PINs) at which recognition routes converge, and which allow access to a common pool of semantics. We present three experiments that examine semantic priming for different decisions. Priming for a semantic decision (e.g., British/American?) shows exactly the same pattern that is normally observed for a familiarity decision. The pattern is equivalent for name and face recognition. However, no semantic priming is observed when participants are asked to make a sex decision. These results constrain future models of face processing and are discussed with reference to current theories of semantic priming.     

Stimulus/response learning in masked congruency priming of faces: Evidence for covert mental classifications?

Reaction times for categorization of a probe face according to its sex or fame were contrasted as a function of whether the category of a preceding, sandwich-masked prime face was congruent or incongruent. Prime awareness was measured by the ability to later categorize the primes, and this was close to chance and typically uncorrelated with priming. When prime faces were never presented as visible probes within a test, priming was not reliable; when prime faces were also seen as probes, priming was only reliable if visible and masked presentation of faces were interleaved (not simply if primes had been visible in a previous session). In the latter case, priming was independent of experimentally induced face–response or face–category contingencies, ruling out any simple form of stimulus–response learning. We conclude that the reliable masked congruency priming reflects bindings between stimuli and multiple, abstract classifications that can be generated both overtly and covertly.     

Stimulus/response learning in masked congruency priming of faces: evidence for covert mental classifications?

Reaction times for categorization of a probe face according to its sex or fame were contrasted as a function of whether the category of a preceding, sandwich-masked prime face was congruent or incongruent. Prime awareness was measured by the ability to later categorize the primes, and this was close to chance and typically uncorrelated with priming. When prime faces were never presented as visible probes within a test, priming was not reliable; when prime faces were also seen as probes, priming was only reliable if visible and masked presentation of faces were interleaved (not simply if primes had been visible in a previous session). In the latter case, priming was independent of experimentally induced face-response or face-category contingencies, ruling out any simple form of stimulus-response learning. We conclude that the reliable masked congruency priming reflects bindings between stimuli and multiple, abstract classifications that can be generated both overtly and covertly.     

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.     

Dynamic variations in affective priming

The present study investigates the dynamics of emotional processing and awareness using an affective facial priming paradigm in conjunction with a multimodal assessment of awareness. Key facial primes are visually masked, and are presented for brief (unconscious) and extended (conscious) durations. Using a preference measure, we examine whether the effects of the primes differ qualitatively (Murphy & Zajonc, 1993). We show that: (a) unconscious affective priming with faces emerges strongly in initial presentations and diminishes rapidly with repetition; (b) conscious affective priming also emerges strongly in initial presentations, however it persists in strength with repetition; and (c) in contrast to other reports on the salience of negative stimuli, happy faces appear more salient than sad faces when presented outside awareness. We discuss the limits and extensions of unconscious affective priming with faces, and consider several methodological and conceptual questions concerning emotional processing out of awareness.     

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.     

Long-term effects of covert face recognition

Covert face recognition has previously been thought to produce only very short-lasting effects. In this study we demonstrate that manipulating subjects' attentional load affects explicit, but not implicit memory for faces, and that implicit effects can persist over much longer intervals than is normally reported. Subjects performed letter-string tasks of high vs. low perceptual load (Lavie, N. (1995). Perceptual load as a necessary condition for selective attention. Journal of Experimental Psychology: Human Perception and Perfomance. 21, 451-468.), while ignoring task-irrelevant celebrity faces. Memory for the faces was then assessed using (a) a surprise recognition test for the celebrities' names, and (b) repetition priming in a face familiarity task. The load manipulation strongly influenced explicit recognition memory, but had no effect on repetition priming from the same items. Moreover, faces from the high load condition produced the same amount of priming whether they were explicitly remembered or not. This result resolves a long-standing anomaly in the face recognition literature, and is discussed in relation to covert processing in prosopagnosia.     

Recognizing the un-real McCoy: priming and the modularity of face recognition

Fodor (1983) has proposed that face perception is carried out by an informationally encapsulated module, whose operation is unaffected by context or expectancies. We tested the modularity hypothesis by examining whether discriminations between normal and distorted versions of famous faces can be primed, either by the name of an associated person (semantic context) or by a valid cue as to the identity of the target face (expectancy). A preliminary experiment showed that, in the absence of priming, discriminations between normal and distorted versions of a face were unaffected by whether the target faces were familiar or not, confirming that these judgments tap perceptual, not postperceptual (semantic), coding processes. In Experiment 1, accuracy was significantly higher when target face pairs were preceded by related name primes, as compared with unrelated ones. In Experiment 2, reaction times were significantly faster for targets preceded by a valid identity cue than for targets preceded by an invalid one. Neither effect could be explained as a speed—accuracy tradeoff. These results fail to support Fodor’s conjecture that face processing is encapsulated.     

The missing link between faces and names: Evidence from Alzheimer's disease patients

Retrieval of proper names is a cause of concern and complaint among elderly adults and it is an early symptom of patients suffering from neurodegenerative diseases such as Alzheimer's disease (AD). While it is well established that AD patients have deficits of proper name retrieval, the nature of such impairment is not yet fully understood. Specifically, it is unknown whether this deficit is due to a degradation of the links between faces and proper names, or due to deficits in intentionally accessing and retrieving proper names from faces. Here, we aim to investigate the integrity of the links between famous faces and proper names in AD while minimizing the impact of the explicit retrieval. We compare the performances of AD patients and elderly controls in a face-name priming task. We assess the integrity of the link between faces and names at two different levels: identity level - the name and face belong to the same person; and semantic level - the name and face belong to the same category (e.g., politicians). Our results reveal that AD patients compared with controls show intact semantic priming but reduced priming for person identity. This suggests that the deficits in intentionally retrieving proper names in AD are the result of a partial disruption of the network at the identity level, i.e., the links between known faces and proper names.     

Affect Is Greater Than,Not Equal to,Condition: Condition and Person Effects in Affective Priming Paradigms

Affective primes may impact ensuing behavior through condition and person effects. However, previous research has not experimentally disentangled these two sources of influence in affective priming paradigms. In the current research, we simultaneously examine the influence of condition factors, in terms of prime valence, and person factors, in terms of affect reactivity and personality. In both studies, undergraduate participants (total N = 174) were primed with either positive or negative affective stimuli (words, Study 1; pictures, Study 2) prior to judging the likability of a neutral target (Arabic characters, Study 1; inkblots, Study 2). Although we did observe between‐condition differences for positive and negative primes, person‐level effects were more consistent predictors of target ratings. Affect reactivity (affect Time 2, controlling Time 1) to the primes predicted evaluative judgments, even in the absence of condition effects. In addition, the personality traits of Neuroticism (Study 1) and behavioral inhibition system sensitivity (Study 2) predicted evaluative judgments of neutral targets following negative affective primes. With effects for condition, affect reactivity, and personality, our results suggest that affective primes influence ensuing behaviors through both informational and affective means. Research using affective priming methodologies should take into account both condition and person‐level effects.     

Affective reactions to facial identity in a prosopagnosic patient

This study probes whether a prosopagnosic patient can make accurate explicit affective judgements towards faces. Patient MJH was shown photographs of faces of well-liked family members and public figures rated as “evil” by opinion polls. MJH was asked to rate each face on two 7-point scales (Likeability and Pleasantness). Since he is unable to explicitly recognise faces, his ratings were based on his evaluative reaction to the faces presented. In a second phase of the experiment, MJH was told the name of the faces previously presented and asked to rate them using the same scales. MJH's Likeability ratings during the picture-viewing phase of the experiment and the explicit phase were highly correlated. Based on these findings, we propose that thought consists of an explicit declarative and an implicit emotional aspect, which may become dissociated in prosopagnosia.     

Long-lasting effects of subliminal affective priming from facial expressions

Unconscious processing of stimuli with emotional content can bias affective judgments. Is this subliminal affective priming merely a transient phenomenon manifested in fleeting perceptual changes, or are long-lasting effects also induced? To address this question, we investigated memory for surprise faces 24 h after they had been shown with 30-ms fearful, happy, or neutral faces. Surprise faces subliminally primed by happy faces were initially rated as more positive, and were later remembered better, than those primed by fearful or neutral faces. Participants likely to have processed primes supraliminally did not respond differentially as a function of expression. These results converge with findings showing memory advantages with happy expressions, though here the expressions were displayed on the face of a different person, perceived subliminally, and not present at test. We conclude that behavioral biases induced by masked emotional expressions are not ephemeral, but rather can last at least 24 h.     

Explicit and implicit stereotype activation effects on memory: do age and awareness moderate the impact of priming?

Two studies examined the effects of implicit and explicit priming of aging stereotypes. Implicit primes had a significant effect on older adults' memory, with positive primes associated with greater recall than negative primes. With explicit primes, older adults were able to counteract the impact of negative stereotypes when the cues were relatively subtle, but blatant stereotype primes suppressed performance regardless of prime type. No priming effects under either presentation condition were obtained for younger adults, indicating that the observed implicit effects are specific to those for whom the stereotype is self-relevant. Findings emphasize the importance of social-situational factors in determining older adults' memory performance and contribute to the delineation of situations under which stereotypes are most influential.     

Learning associations between action and perception: effects of incompatible training on body part and spatial priming

Observation of another person executing an action primes the same action in the observer's motor system. Recent evidence has shown that these priming effects are flexible, where training of new associations, such as making a foot response when viewing a moving hand, can reduce standard action priming effects (Gillmeister, Catmur, Liepelt, Brass, & Heyes, 2008). Previously, these effects were obtained after explicit learning tasks in which the trained action was cued by the content of a visual stimulus. Here we report similar learning processes in an implicit task in which the participant's action is self-selected, and subsequent visual effects are determined by the nature of that action. Importantly, we show that these learning processes are specific to associations between actions and viewed body parts, in that incompatible spatial training did not influence body part or spatial priming effects. Our results are consistent with models of visuomotor learning that place particular emphasis on the repeated experience of watching oneself perform an action.