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.     

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.     

Repetition priming of face gender judgments: An instance based explanation

Earlier studies of repetition priming using faces have been interpreted as indicating that such effects are confined to the processing of known faces. The experiment reported here employed eight rather than the more usual two presentation trials and required subjects to make gender decisions (is it a male or is it a female face?) to both familiar and unfamiliar faces. This allowed the currently favored recognition unit theories of face processing to be compared with the Logan (1988) instance model. Equivalent repetition priming effects were observed for both familiar and unfamiliar faces and were well fitted by power functions. It is argued that the findings are consistent with the strong predictions made by Logan's model and pose problems for recognition unit based theories.     

Repetition priming of face gender judgments: An instance based explanation

Earlier studies of repetition priming using faces have been interpreted as indicating that such effects are confined to the processing of known faces. The experiment reported here employed eight rather than the more usual two presentation trials and required subjects to make gender decisions (is it a male or is it a female face?) to both familiar and unfamiliar faces. This allowed the currently favored recognition unit theories of face processing to be compared with the Logan (1988) instance model. Equivalent repetition priming effects were observed for both familiar and unfamiliar faces and were well fitted by power functions. It is argued that the findings are consistent with the strong predictions made by Logan's model and pose problems for recognition unit based theories.     

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.     

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 face recognition

Three experiments investigating the priming of the recognition of familiar faces are reported. In Experiment 1, recognizing the face of a celebrity in an “Is this face familiar?” task was primed by exposure several minutes earlier to a different photograph of the same person, but not by exposure to the person's written name (a partial replication of Bruce and Valentine, 1985). In Experiment 2, recognizing the face of a personal acquaintance was again primed by recognizing a different photograph of their face, but not by recognizing the acquaintance from that person's body shape, clothes etc. Experiment 3 showed that maximum repetition priming is obtained from prior exposure to an identical photograph of a famous face, less from a similar photograph, and least (but still significant) from a dissimilar photograph.

We argue that repetition priming is a function of the degree of physical similarity between two stimuli and that lack of priming between different stimulus types (e.g., written names and faces, or bodies and faces) may be attributable to lack of physical similarity between prime and test stimuli. Repetition priming effects may be best explained by some form of “instance-based” model such as that proposed by McClelland and Rumelhart (1985).     

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.     

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.     

Repetition priming of access to biographical information from faces

Two experiments examined repetition priming on tasks that require access to semantic (or biographical) information from faces. In the second stage of each experiment, participants made either a nationality or an occupation decision to faces of celebrities, and, in the first stage, they made either the same or a different decision to faces (in Experiment 1) or the same or a different decision to printed names (in Experiment 2). All combinations of priming and test tasks produced clear repetition effects, which occurred irrespective of whether the decisions made were positive or negative. Same-domain (face-to-face) repetition priming was larger than cross-domain (name-to-face) priming, and priming was larger when the two tasks were the same. It is discussed how these findings are more readily accommodated by the Burton, Bruce, and Johnston (1990) model of face recognition than by episode-based accounts of repetition priming.     

Priming global and local processing of composite faces: revisiting the processing-bias effect on face perception

We used the composite-face illusion and Navon stimuli to determine the consequences of priming local or global processing on subsequent face recognition. The composite-face illusion reflects the difficulty of ignoring the task-irrelevant half-face while attending the task-relevant half if the half-faces in the composite are aligned. On each trial, participants first matched two Navon stimuli, attending to either the global or the local level, and then matched the upper halves of two composite faces presented sequentially. Global processing of Navon stimuli increased the sensitivity to incongruence between the upper and the lower halves of the composite face, relative to a baseline in which the composite faces were not primed. Local processing of Navon stimuli did not influence the sensitivity to incongruence. Although incongruence induced a bias toward different responses, this bias was not modulated by priming. We conclude that global processing of Navon stimuli augments holistic processing of the face.     

Repetition priming of access to biographical information from faces

Two experiments examined repetition priming on tasks that require access to semantic (or biographical) information from faces. In the second stage of each experiment, participants made either a nationality or an occupation decision to faces of celebrities, and, in the first stage, they made either the same or a different decision to faces (in Experiment 1) or the same or a different decision to printed names (in Experiment 2). All combinations of priming and test tasks produced clear repetition effects, which occurred irrespective of whether the decisions made were positive or negative. Same-domain (face-to-face) repetition priming was larger than cross-domain (name-to-face) priming, and priming was larger when the two tasks were the same. It is discussed how these findings are more readily accommodated by the Burton, Bruce, and Johnston () model of face recognition than by episode-based accounts of repetition priming.     

The effects of distinctiveness in recognising and classifying faces

In an earlier study it was found that distinctive familiar faces were recognised faster than typical familiar faces in a familiarity decision task. In the first experiment reported here this effect was replicated with the use of celebrities' faces rather than personally familiar faces. In the second and third experiments the effect of distinctiveness was found to reverse if the task was to distinguish between faces and jumbled faces. Subjects took longer to classify distinctive faces as faces than they did to classify typical faces. Thus distinctive faces were recognised faster, but were classified as faces more slowly than were typical faces, both when personally familiar faces and when famous faces were used as stimuli. These results are interpeted as evidence that faces are encoded by reference to a general face prototype.     

On facial expertise: processing strategies of twins' parents

Parents of monozygotic twins typically learn to recognise their own children and also to tell them apart on photographs. However, it is unknown whether such exemplar expertise can be generalised to unfamiliar faces of equal similarity (ie other twins). In the present study, parents of monozygotic twins were compared to 'control' parents whose children were non-twin siblings. In a same/different task with familiar and unfamiliar twin faces as stimuli, twins' parents were faster than control parents in distinguishing their own children, but slower when distinguishing unfamiliar twin faces. These unexpected findings can be interpreted as a generalisation of a habitual perceptual strategy that is efficient only with familiar face exemplars. When pictures of the twins' faces were inverted by 180degrees, the typical inversion costs for familiar faces were observed, but the twins' parents recognised unfamiliar twins' faces better when these were inverted than when upright. This inverted inversion effect could be caused by the high similarity of the face pairs as well as by experience with familiar faces of equally high similarity. We conclude that the facial expertise of twins' parents is idiosyncratic to their own children and not based on an enhanced general facial expertise.     

Discrimination of human and dog faces and inversion responses in domestic dogs (Canis familiaris)

Although domestic dogs can respond to many facial cues displayed by other dogs and humans, it remains unclear whether they can differentiate individual dogs or humans based on facial cues alone and, if so, whether they would demonstrate the face inversion effect, a behavioural hallmark commonly used in primates to differentiate face processing from object processing. In this study, we first established the applicability of the visual paired comparison (VPC or preferential looking) procedure for dogs using a simple object discrimination task with 2D pictures. The animals demonstrated a clear looking preference for novel objects when simultaneously presented with prior-exposed familiar objects. We then adopted this VPC procedure to assess their face discrimination and inversion responses. Dogs showed a deviation from random behaviour, indicating discrimination capability when inspecting upright dog faces, human faces and object images; but the pattern of viewing preference was dependent upon image category. They directed longer viewing time at novel (vs. familiar) human faces and objects, but not at dog faces, instead, a longer viewing time at familiar (vs. novel) dog faces was observed. No significant looking preference was detected for inverted images regardless of image category. Our results indicate that domestic dogs can use facial cues alone to differentiate individual dogs and humans and that they exhibit a non-specific inversion response. In addition, the discrimination response by dogs of human and dog faces appears to differ with the type of face involved.     

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.     

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.     

Facilitative and interference effects of facial expressions on familiarity as a function of repetition priming frequency

Facial expressions of familiar faces have been found to influence identification. In this study, we hypothesize that faces with emotional expression are encoded for both structural and variant information resulting in more robust identification. Eighty-eight participants were presented faces with repetition priming frequencies of 2, 5, 10, and 20 (learning stage) and then judged the faces in terms of familiarity (testing stage). Participants were randomized into one of the following conditions: The facial expression between learning and testing stage remained the same (F-F), faces with facial expression shown in the learning stage were neutralized in the testing stage (F-N), or faces with neutral expressions shown in the learning stage had emotional expressions in the testing stage (N-F). Results confirmed our hypothesis and implications are discussed.