Repetition priming and face processing: Priming occurs within the system that responds to the identity of a face

A familiar stimulus that has recently been recognized will be recognized a second time more quickly and more accurately than if it had not been primed by the earlier encounter. This is the phenomenon of “repetition priming”. Four experiments on repetition priming of face recognition suggest that repetition priming is a consequence of changes within the system that responds to the familiarity of a stimulus. In Experiment 1, classifying familiar faces by occupation facilitated subsequent responses to the same faces in a familiarity decision task (Is this face familiar or unfamiliar?) but not in an expression decision task (Is this face smiling or unsmiling?) or a sex decision task (Is this face male or female?). In Experiment 2, familiar faces showed repetition priming in a familiarity decision task, regardless of whether a familiarity judgment or an expression judgment had been required when the faces were first encountered. Expression decisions to familiar faces again failed to show repetition priming. In Experiment 3, familiar faces showed repetition priming in a familiarity decision task, regardless of whether a familiarity judgment or a sex judgment had been asked for when the faces were first encountered. Sex decisions to familiar faces again failed to show repetition priming. In Experiment 4, familiarity decisions continued to show repetition priming when a brief presentation time with encouragement to respond while the face was displayed reduced response latencies to speeds comparable to those for sex and expression judgments in Experiments 1 to 3. The results are problematic for theories that propose that repetition priming is mediated by episodic records of previous acts of stimulus encoding.     

Repetition Priming Follows Spontaneous but not Prompted Recognition of Familiar Faces

Reaction times to make a familiarity decision to the faces of famous people were measured after recognition of the faces in a pre-training phase had occurred spontaneously or following prompting with a name or other cue. At test, reaction times to familiar faces that had been recognized spontaneously in the pre-training phase were significantly facilitated relative to an unprimed comparison condition. Reaction times to familiar faces recognized only after prompting in the pre-training phase were not significantly facilitated. This was demonstrated both when a name prompt was used (Experiments 1 and 3) and when subjects were cued with brief semantic information (Experiment 2).

Repetition priming was not found to depend on prior spontaneous recognition per se. In Experiment 3, spontaneously recognizing a familiar face did not prime subsequent familiarity judgements when the same face had only been identified following prompting on a prior encounter. In Experiment 4, recognition memory for faces recognized after cueing was found to be over 90% accurate. This indicates that prompted recognition does not yield repetition priming, even though subjects can remember the faces. A fusion of “face recognition unit” and “episodic record” accounts of the repetition priming effect may be more useful than either theory alone in explaining these results.     

Best face forward: Similarity effects in repetition priming of face recognition

Two experiments examined the graded similarity effect in the repetition priming of familiar face recognition. From the model of repetition priming proposed by Burton, Bruce, and Johnston (1990) it was predicted that similarity effects may be a confound of stimulus preparation. Experiment 1 was used to discount this hypothesis, but failed to replicate a pattern of graded priming related to the similarity of prime and target faces. Experiment 2 attempted a more extensive investigation using two different measures of prime-target similarity. The results replicated Ellis, Young, Flude, and Hay's (1987) finding that similar primes confer more priming than dissimilar ones, but found no correlation between amount of priming and the degree of prime-target resemblance for either similarity metric used. In view of these findings the mechanism of repetition priming in familiar face recognition is discussed.     

Repeated Repetition Priming in Face Recognition

Prior exposure to an item can facilitate subsequent recognition of that item. This effect, known as repetition priming, has been found for the recognition of many stimuli including faces (Bruce & Young, 1986). Three experiments are reported, which investigated whether repetition priming is limited to the first repetition or whether subsequent repetitions continually act to increase the speed of face processing. Experiment 1 demonstrated that repetition can reduce categorization time for faces after the first exposure, and this effect is independent of practice effects. Experiment 2 demonstrated that the relationship between reaction time and number of repetitions fits a negative power function. Experiment 3 investigated how delay affects this power function. Delay was found to decrease the negative gradient of the power curve. The effects of priming and delay are discussed in terms of the predictions made by Burton's (1994) interactive activation and competition with learning (IACL) model of face recognition and accounts of automaticity.     

Auditory Long term Memory: Repetition Priming of Voice Recognition

Two experiments examined repetition priming in the recognition of famous voices. In Experiment 1, reaction times for fame decisions to famous voice samples were shorter than in an unprimed condition, when voices were primed by a different voice sample of the same person having been presented in an earlier phase of the experiment. No effect of voice repetition was observed for non-famous voices. In Experiment 2, it was investigated whether this priming effect is voice-specific or whether it is related to post-perceptual processes in person recognition. Recognizing a famous voice was again primed by having earlier heard a different voice sample of that person. Although an earlier exposure to that person's name did not cause any priming, there was some indication of priming following an earlier exposure to that person's face. Finally, earlier exposure to the identical voice sample (as compared to a different voice sample from the same person) caused a considerable bias towards responding 'famous'-i.e. performance benefits for famous but costs for nonfamous voices. The findings suggestthat (1) repetition priming invoice recognition primarily involves the activation of perceptual representations of voices, and (2) it is important to determine the conditions in which priming causes bias effects that need to be disentangled from performance benefits.     

Multiple contributions to priming effects for familiar faces: analyses with backward masking and event-related potentials

The model of face recognition by Bruce and Young postulates a pool of structural representations for familiar faces in long-term memory, so-called face recognition units (FRUs). Event-related brain potentials show early repetition priming effects for familiar faces around 250-300 ms [N250r or early repetition effect (ERE)], which are thought to reflect the activation of these FRUs. However, small N250r effects are also seen for unfamiliar faces suggesting that priming of perceptual codes (i.e., pictorial and structural codes) also contributes to early repetition effects. Using a face-familiarity task in Experiment 1, we aimed to eliminate these perceptual contributions to face priming by backward masking the prime face with a different, unfamiliar face. As expected, a repetition priming effect appeared only for familiar faces. Experiment 2 used a semantic-decision task and compared the effects of different kinds of masks that interfered with either pictorial codes or with pictorial and structural codes. Our findings indicate that both structural codes and memory representations contribute to the N250r and that unfamiliar-face masks interfere only with structural codes. Face-masks may therefore provide a useful tool to extract the pure contributions of memory representations (i.e., FRUs) to repetition priming.     

Neuropsychological Impairment of Face Recognition Units

Despite the absence of “conscious”, overt identification, some patients with face recognition impairments continue covertly to process information regarding face familiarity. The fact that by no means all patients show these covert effects has led to the suggestion that indirect recogntion tasks may help in identifying different types of face recognition impairment. The present report describes a number of experiments with the patient NR, who, after a closed head injury, has been severely impaired at recognizing familiar faces. Investigations mostly failed to show overt or covert face recognition, but NR performed at an above-chance level in selecting the familiar face on a task requiring a forced-choice between a familiar and an unfamiliar face. This discrepancy between a degree of rudimentary overt recognition and absence of covert effects on most indirect tests was addressed using a cross-domaim identity priming paradigm. This examined separately the possibility of preserved recognition for faces that NR consistently chose correctly in a forced-choice familiarity decision and those on which he performed at chance level. Priming effects were apparent only for the faces that were consistently chosen as “familiar” in forced-choice. We suggest that NR's stored representations of familiar faces are degraded, so that face recognition is possible only via a limited set of relatively preserved representations able to support a rudimentary form of overt recognition and to facilitate performance in matching and priming tasks.     

Testing instance models of face repetition priming

Two experiments examining repetition priming in face recognition are reported. They employed eight rather than the more usual two presentation trials so that the prediction made by Logan's (1988) instance model of power function speedup of response time (RT) distributions could be examined. In Experiment 1, we presented the same photograph on each trial; in Experiment 2, we presented photographs of varying poses. Both experiments showed repetition priming effects for familiar and unfamiliar faces, power function speedup for both the mean and the standard deviation of RT and the power function speedup of the quanties of the RT distributions. We argue that our findings are consistent with the predictions made by the instance model and provide an explanatory challenge for alternative theoretical approaches.     

Haven't we met before? The effect of facial familiarity on repetition priming

Within the word recognition literature, word‐frequency and hence familiarity has been shown to affect the degree of repetition priming. The current paper reports two experiments which examine whether familiarity also affects the degree of repetition priming for faces. The results of Experiment 1 confirmed that familiarity did moderate the degree of priming in a face recognition task. Low familiarity faces were primed to a significantly greater degree than high familiarity faces in terms of accuracy, speed, and efficiency of processing. Experiment 2 replicated these results but additionally, demonstrated that familiarity moderates priming for name recognition as well as face recognition. These results can be accommodated within both a structural account of repetition priming ( Burton, Bruce & Johnston, 1990 ) and an Episodic Memory account of repetition priming (see Roediger, 1990 ), and are discussed in terms of a common mechanism for priming, learning and the representation of familiarity.     

Incomplete Faces Don't Show the Whole Picture: Repetition Priming from Jumbled Faces

Four experiments examined repetition priming of familiarity decisions to faces of famous people by the prior exposure of intact or jumbled faces. In Experiments 1 and 2 the primes were either the identical picture of the target face or a picture of the face with the internal features jumbled up. (In Experiment 2 the external features were also removed from all faces.) Compared with response times to previously unseen faces, familiarity decisions were made more rapidly if the subject had seen and identified the famous face in the pre-training stage; this was independent of whether they saw an intact or jumbled face. Priming was not shown if the face was not recognized earlier. Experiment 3 demonstrated that, if faces were not recognized spontaneously in the pre-training stage, being prompted as to their identity by the experimenter still did not yield priming at test-a result that replicated a previous study using incomplete faces (Brunas-Wagstaff, Young, & Ellis, 1992). Experiment 4 showed that it was the situation in which the information was given that was critical in determining whether priming occurred. The findings of this study are related to mechanisms for repetition priming of faces and used to discuss the necessity of modifications to the Bruce and Young (1986) model such as those offered by Burton, Bruce, and Johnston (1990).     

面孔重复启动效应:知觉结构和语义表征的贡献

以30名大学生为被试,探讨了熟悉和陌生的正倒立面孔对重复启动效应的影响,以此考察知觉结构和语义表征对面孔重复启动的贡献.结果表明:(1)熟悉面孔的重复启动既存在知觉启动也存在语义启动,而不熟悉面孔仅仅存在知觉启动.(2)知觉结构和语义表征对启动效应的贡献是联合的,而不是分离的;在熟悉面孔中,语义表征对重复启动的贡献大于知觉结构的贡献.(3)知觉结构和语义表征对重复启动的贡献与加工阶段有关.知觉结构在初始阶段起作用,随后作用逐渐减弱;而语义表征存在于信息加工的整个过程.     

Cross-domain Repetition Priming in Person Recognition

Three experiments examining repetition priming of personal names are reported. In each experiment, faces are used as prime stimuli and people's names as the test stimuli. Experiment 1 fails to demonstrate priming from faces to names when the same task-a familiar/ unfamiliar judgement-is made in prime and test phases. Experiment 2 shows that priming is observed when the same semantic judgement (British/ American) is made in prime and test phases. Experiment 3 shows that priming is observed when different semantic judgements (dead/ alive, British/ American) are made at prime and test phase. These results suggest that transfer appropriate processing cannot provide the sole account of repetition priming in person recognition. Instead, the results are interpreted in terms of a structural account of priming, embedded within an interactive activation and competition model of person recognition.     

Lateralized repetition priming for familiar faces: Evidence for asymmetric interhemispheric cooperation

Repetition priming refers to facilitated recognition of stimuli that have been seen previously. Although a great deal of work has examined the properties of repetition priming for familiar faces, little has examined the neuroanatomical basis of the effect. Two experiments are presented in this paper that combine the repetition priming paradigm with a divided visual field methodology to examine lateralized recognition of familiar faces. In the first experiment participants were presented with prime faces unilaterally to each visual field and target faces foveally. A significant priming effect was found for prime faces presented to the right hemisphere, but not for prime faces presented to the left hemisphere. In Experiment 2, prime and target faces were presented unilaterally, either to the same visual field or to the opposite visual field (i.e., either within hemisphere or across hemispheres). A significant priming effect was found for the within right hemisphere condition, but not for the within left hemisphere condition, replicating the findings of the first experiment. Priming was also found in both of the across hemispheres conditions, suggesting that interhemispheric cooperation occurs to aid recognition. Taken in combination these experiments provide two main findings. First, an asymmetric repetition priming effect was found, possibly as a result of asymmetric levels of activation following recognition of a prime face, with greater priming occurring within the right hemisphere. Second, there is evidence for asymmetric interhemispheric cooperation with transfer of information from the right hemisphere to the left hemisphere to facilitate recognition.     

Lateralized repetition priming for familiar faces: Evidence for asymmetric interhemispheric cooperation

Repetition priming refers to facilitated recognition of stimuli that have been seen previously. Although a great deal of work has examined the properties of repetition priming for familiar faces, little has examined the neuroanatomical basis of the effect. Two experiments are presented in this paper that combine the repetition priming paradigm with a divided visual field methodology to examine lateralized recognition of familiar faces. In the first experiment participants were presented with prime faces unilaterally to each visual field and target faces foveally. A significant priming effect was found for prime faces presented to the right hemisphere, but not for prime faces presented to the left hemisphere. In Experiment 2, prime and target faces were presented unilaterally, either to the same visual field or to the opposite visual field (i.e., either within hemisphere or across hemispheres). A significant priming effect was found for the within right hemisphere condition, but not for the within left hemisphere condition, replicating the findings of the first experiment. Priming was also found in both of the across hemispheres conditions, suggesting that interhemispheric cooperation occurs to aid recognition. Taken in combination these experiments provide two main findings. First, an asymmetric repetition priming effect was found, possibly as a result of asymmetric levels of activation following recognition of a prime face, with greater priming occurring within the right hemisphere. Second, there is evidence for asymmetric interhemispheric cooperation with transfer of information from the right hemisphere to the left hemisphere to facilitate recognition.     

Repetition Priming of the Recognition of Familiar Proper Names

Three experiments examined repetition priming of the recognition of printed proper names of familiar people by the prior exposure of those names in their correct form or with their letters re-arranged as anagrams. Experiment 1 found that, compared with response times to previously unseen names, name familiarity decisions were made more rapidly if the subject had seen and identified the famous name in the pre-training stage, irrespective of whether they saw the intact name or an anagram. Priming was not demonstrated if the name was not recognized in the pre-training stage. The results of Experiment 2 suggested that if anagrams were not solved spontaneously in the pre-training stage, being prompted to their identity by the experimenter would not yield reliable priming at test, a result that reflected previous work using face stimuli (Brunas-Wagstaff, Young, & Ellis, 1992; Johnston, Barry, & Williams, 1996). In Experiment 3, prompts were given for all names and anagrams presented at pretraining. Subsequent priming was demonstrated only for names identified spontaneously, which showed that, as with face recognition, it was the situation in which the prime was given that was critical in determining whether priming of name recognition occurred. The findings are used to develop proposed extensions of the Bruce and Young (1986) model such as that offered by Burton, Bruce, and Johnston (1990).     

Self Priming: A Short term Benefit of Repetition

Burton, Bruce, and Johnston (1990) developed an interactive activation and competition (IAC) model of person recognition that gives a parsimonious account of semantic and repetition priming effects with seen faces and names. This model predicts that a familiarity decision to a person's name should be facilitated if the name is immediately preceded by the same person's face (or vice versa); Burton et al. (1990) called this effect 'self priming'. In three experiments, we explored properties of self priming predicted from Burton et al.'s (1990) IAC model. When each stimulus is seen on only one trial, the Burton et al. (1990) model predicts that within-domain self priming (e.g. name prime-name target) should produce more facilitation than cross-domain self priming (e.g. face prime-name target). This prediction was investigated in Experiments 1 and 2; results were consistent with it. Two further predictions from the Burton et al. (1990) model are that the amounts of withinand cross-domain self priming should not differ when subjects are primed to recognize the targets by prior encounters during the experiment, and that self priming should produce more facilitation than semantic priming. Results of Experiment 3 were again consistent with both predictions. We conclude that the Burton et al. (1990) IAC model stands the test of further rigorous examination.     

The effects of massive repetition on speeded recognition of faces

Models of face processing suggest that recognizing a person should prime recognition of a consecutive, but different, image of the same person. This prediction is tested in four experiments using large blocks of different views of the same person. The experiments demonstrate that reaction times decreased according to a negative power function as the number of repetitions increased. After sufficient repetitions, however, the reaction times lengthened. The presentation of a different familiar person between blocks of repetitions caused the reaction time for the target to increase to a level equivalent to that with no repetitions. Experiments 2 and 3 investigated the effect of different intervening stimuli (unfamiliar faces and objects). Such stimuli reduced the effect of mass repetition-but the reduction using a familiar face was greater than that with either unfamiliar faces or objects. Experiment 4 confirmed that the effects of massive repetition occur for a face familiarity task as well as for face identification tasks. The results are discussed in termsof the predictions of Burton's (1994) IACL model.     

Prime time advertisements: Repetition priming from faces seen on subject recruitment posters

Repetition priming is defined as a gain in item recognition after previous exposure. Repetition priming of face recognition has been shown to last for several months, despite contamination by everyday exposure to both experimental and control faces in the interval. Here we show that gains in face recognition in the laboratory are found from faces initially seen in a rather different context— on subject recruitment posters, even when the advertisements make no specific mention of experiments involving face recognition. The priming was greatest when identical pictures were shown in the posters and in the test phase, although different views of faces did give significant priming in one study. Follow-up studies revealed poor explicit memory for the faces shown on the posters. The results of these experiments are used to develop a model in which repetition priming reflects the process of updating representations of familiar faces.     

Repetition priming and recognition of dynamic and static chimeras

Chimeric faces, produced by combining the top half of a familiar face with the bottom half of a different familiar face, are difficult to recognise explicitly. However, given that they contain potentially useful configurational and featural information for face recognition, they might nevertheless produce some activation of representations of their constituent faces. Repetition priming with dynamic and static facial chimeras was used to test this possibility. Whereas half-faces produced significant repetition priming of their familiar counterparts, both types of chimera did not. When analyses were restricted to faces that were recognised during the prime phase, repetition priming was both significant, and equivalent, for chimeras and half-faces. The results suggest that the constituents of a facial chimera must be parsed, and recognised, in order for them to cause repetition priming for their familiar counterparts. Facial motion does not help with the parsing of a facial chimera.     

What happens to our representation of identity as familiar faces age? Evidence from priming and identity aftereffects

Matching identity in images of unfamiliar faces is error prone, but we can easily recognize highly variable images of familiar faces – even images taken decades apart. Recent theoretical development based on computational modelling can account for how we recognize extremely variable instances of the same identity. We provide complementary behavioural data by examining older adults’ representation of older celebrities who were also famous when young. In Experiment 1, participants completed a long-lag repetition priming task in which primes and test stimuli were the same age or different ages. In Experiment 2, participants completed an identity after effects task in which the adapting stimulus was an older or young photograph of one celebrity and the test stimulus was a morph between the adapting identity and a different celebrity; the adapting stimulus was the same age as the test stimulus on some trials (e.g., both old) or a different age (e.g., adapter young, test stimulus old). The magnitude of priming and identity after effects were not influenced by whether the prime and adapting stimulus were the same age or different age as the test face. Collectively, our findings suggest that humans have one common mental representation for a familiar face (e.g., Paul McCartney) that incorporates visual changes across decades, rather than multiple age-specific representations. These findings make novel predictions for state-of-the-art algorithms (e.g., Deep Convolutional Neural Networks).