What types of visual recognition tasks are mediated by the neural subsystem that subserves face recognition?

Three divided visual field experiments tested current hypotheses about the types of visual shape representation tasks that recruit the cognitive and neural mechanisms underlying face recognition. Experiment 1 found a right hemisphere advantage for subordinate but not basic-level face recognition. Experiment 2 found a right hemisphere advantage for basic but not superordinate-level animal recognition. Experiment 3 found that inverting animals eliminates the right hemisphere advantage for basic-level animal recognition. This pattern of results suggests that the cognitive and neural mechanisms underlying face recognition are recruited when computational demands of a shape representation task are best served through the use of coordinate (rather than categorical) spatial relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of active exploration of 3D face stimuli on recognition memory of facial information.

Research on face recognition has mainly relied on methods in which observers are relatively passive viewers of face stimuli. This study investigated whether active exploration of three-dimensional (3D) face stimuli could facilitate recognition memory. A standard recognition task and a sequential matching task were employed in a yoked design. Observers in the active condition explored 3D views of faces via a mouse or joystick during the training and test sessions of the task, whereas observers in the passive condition simply viewed the replay of the same sequence of face stimuli generated by the active observers. It was found that the active condition produced better recognition accuracy than the passive condition. The study provides the first evidence that active exploration of 3D face stimuli can lead to better face recognition memory and matching performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Monkeys and mug shots: Cues used by rhesus monkeys (Macaca mulatta) to recognize a human face.

Investigated the cues rhesus monkeys (Macaca mulatta) use to recognize a familiar human face. To manipulate facial cues, schematic faces were constructed with Identi-Kit materials derived from mug shots. The monkeys (N?=?4) spontaneously classed Identi-Kit stimuli as faces on initial presentations. The monkeys then learned to distinguish one Identi-Kit face, the standard, from others. Panel presses indicated recognition of the standard eye. Eye movement recordings revealed that the monkeys predominantly fixated on the eyes of the standard face. When the standard face was transformed by removing, altering, or reorienting its features, only alterations of eyes or brows lowered recognition; removal of eyes, brows, nose, or lips did not. Responses to rotated, inverted, and scrambled versions of the standard face varied but generally disrupted recognition. It is concluded that features and configuration were used to recognize the human face. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus type, level of categorization, and spatial-frequencies utilization: Implications for perceptual categorization hierarchies.

The type of visual information needed for categorizing faces and nonface objects was investigated by manipulating spatial frequency scales available in the image during a category verification task addressing basic and subordinate levels. Spatial filtering had opposite effects on faces and airplanes that were modulated by categorization level. The absence of low frequencies impaired the categorization of faces similarly at both levels, whereas the absence of high frequencies was inconsequential throughout. In contrast, basic-level categorization of airplanes was equally impaired by the absence of either low or high frequencies, whereas at the subordinate level, the absence of high frequencies had more deleterious effects. These data suggest that categorization of faces either at the basic level or by race is based primarily on their global shape but also on the configuration of details. By contrast, basic-level categorization of objects is based on their global shape, whereas category-specific diagnostic details determine the information needed for their subordinate categorization. The authors conclude that the entry point in visual recognition is flexible and determined conjointly by the stimulus category and the level of categorization, which reflects the observer’s recognition goal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Older adults' configural processing of faces: Role of second-order information.

Problems with face recognition are frequent in older adults. However, the mechanisms involved have only been partially discovered. In particular, it is unknown to what extent these problems may be related to changes in configural face processing. Here, we investigated the face inversion effect (FIE) together with the ability to detect modifications in the vertical or horizontal second-order relations between facial features. We used a same/different unfamiliar face discrimination task with 33 young and 33 older adults. The results showed dissociations in the performances of older versus younger adults. There was a lack of inversion effect during the recognition of original faces by older adults. However, for modified faces, older adults showed a pattern of performance similar to that of young participants, with preserved FIE for vertically modified faces and no detectable FIE for horizontally modified faces. Most importantly, the detection of vertical modifications was preserved in older relative to young adults whereas the detection of horizontal modifications was markedly diminished. We conclude that age has dissociable effects on configural face-encoding processes, with a relative preservation of vertical compared to horizontal second-order relations processing. These results help to understand some divergent results in the literature and may explain the spared familiar face identification abilities in the daily lives of older adults. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Fearful faces but not fearful eyes alone delay attention disengagement in 7-month-old infants.

Adult-like attentional biases toward fearful faces can be observed in 7-month-old infants. It is possible, however, that infants merely allocate attention to simple features such as enlarged fearful eyes. In the present study, 7-month-old infants (n = 15) were first shown individual emotional faces to determine their visual scanning patterns of the expressions. Second, an overlap task was used to examine the latency of attention disengagement from centrally presented faces. In both tasks, the stimuli were fearful, happy, and neutral facial expressions, and a neutral face with fearful eyes. Eye-tracking data from the first task showed that infants scanned the eyes more than other regions of the face; however, there were no differences in scanning patterns across expressions. In the overlap task, infants were slower in disengaging attention from fearful as compared to happy and neutral faces and also to neutral faces with fearful eyes. Together, these results provide evidence that threat-related stimuli tend to hold attention preferentially in 7-month-old infants and that the effect does not reflect a simple response to differentially salient eyes in fearful faces. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotion-attention interactions in recognition memory for distractor faces.

Effective filtering of distractor information has been shown to be dependent on perceptual load. Given the salience of emotional information and the presence of emotion-attention interactions, we wanted to explore the recognition memory for emotional distractors especially as a function of focused attention and distributed attention by manipulating load and the spatial spread of attention. We performed two experiments to study emotion-attention interactions by measuring recognition memory performance for distractor neutral and emotional faces. Participants performed a color discrimination task (low-load) or letter identification task (high-load) with a letter string display in Experiment 1 and a high-load letter identification task with letters presented in a circular array in Experiment 2. The stimuli were presented against a distractor face background. The recognition memory results show that happy faces were recognized better than sad faces under conditions of less focused or distributed attention. When attention is more spatially focused, sad faces were recognized better than happy faces. The study provides evidence for emotion-attention interactions in which specific emotional information like sad or happy is associated with focused or distributed attention respectively. Distractor processing with emotional information also has implications for theories of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential hemispheric processing of faces: Methodological considerations and reinterpretation.

Examines the procedures and stimuli (physiognomies) used in lateralized face recognition experiments with normal Ss, as well as in related perceptual and identification experiments. Results reveal that in general a left visual field (right hemisphere) advantage is obtained when: (a) stimulus information is degraded; (b) faces to be compared are highly discriminable; (c) set of unfamiliar faces is used; and (d) task requirements allow a lax criterion of recognition. These conditions seem to make holistic processing adequate for the task; if the conditions require analytic judgments, then a right visual field (left hemisphere) advantage may be obtained. Thus, no hemifield has an inherent or absolute advantage and these procedural conditions may critically determine what hemifield advantage is observed in any given experiment with faces (or other types of stimuli). Apparently, both hemispheres may contribute to the processing of faces but their contributions vary as a function of task demands. A right hemisphere advantage may reflect an enhanced role of the processes of configuration, completion, categorization, or set. A left hemisphere advantage need not involve the language function but it may reflect a genuine visuospatial contribution. (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Brain activity differentiates face and object processing in 6-month-old infants.

Event-related potentials were used to determine whether infants, like adults, show differences in spatial and temporal characteristics of brain activation during face and object recognition. Three aspects of visual processing were identified: (a) differentiation of face vs. object (P400 at occipital electrode was shorter latency for faces), (b) recognition of familiar identity (Nc, or negative component, at frontotemporal electrodes [FTEs] was of larger amplitude for familiar stimuli), and (c) encoding novelty (slow wave at FTEs was larger for unfamiliar stimuli). The topography of the Nc was influenced by category type: Effects of familiarity were limited to the midline and right anterior temporal electrodes for faces but extended to all temporal electrodes for objects. Results show that infants' experience with specific examples within categories and their general category knowledge influence the neural correlates of visual processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Face recognition accuracy as a function of mode of representation.

The relative effectiveness of line drawings and photographs as ways of representing information in face reconstruction systems was compared in 2 experiments. In Exp I, 3 independent groups of college students (27 in each group) were required to identify well-known faces shown either as photographs, detailed line drawings, or outline drawings. Photographs were significantly more effective as stimuli than line drawings, which in turn were superior to outlines. In Exp II, 80 Ss aged 16–60 yrs recruited from the public participated in a recognition task. Photographs and detailed line drawings of previously unknown faces served as stimuli. Ss recognized photographs significantly more accurately than line drawings, even when the pose of the target was changed between the exposure and test series. Results are discussed in terms of the development of computer-based face reconstruction systems and theories of face recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention misplaced: The role of diagnostic features in the face-inversion effect.

Inversion disproportionately impairs recognition of face stimuli compared to nonface stimuli arguably due to the holistic manner in which faces are processed. A qualification is put forward in which the first point fixated on is different for upright and inverted faces and this carries some of the face-inversion effect. Three experiments explored this possibility by using fixation crosses to guide attention to the eye or mouth region of the to-be-presented faces in different orientations. Recognition was better when the fixation cross appeared at the eye region than at the mouth region. The face-inversion effect was smaller when the eyes were cued than when the mouth was cued or when there was no cueing. The results suggest that the first facial feature attended to is important for accurate face recognition and this may carry some of the effects of inversion. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Rhesus monkeys (Macaca mulatta) lack expertise in face processing.

Faces are salient stimuli for primates that rely predominantly on visual cues for recognizing conspecifics and maintaining social relationships. While previous studies have shown similar face discrimination processes in chimpanzees and humans, data from monkeys are unclear. Therefore, three studies examined face processing in rhesus monkeys using the face inversion effect, a fractured face task, and an individual recognition task. Unlike chimpanzees and humans, the monkeys showed a general face inversion effect reflected by significantly better performance on upright compared to inverted faces (conspecifics, human and chimpanzees faces) regardless of the subjects' expertise with those categories. Fracturing faces alters first- and second-order configural manipulations whereas previous studies in chimpanzees showed selective deficits for second-order configural manipulations. Finally, when required to individuate conspecific's faces, i.e., matching two different photographs of the same conspecific, monkeys showed poor discrimination and repeated training. These results support evolutionary differences between rhesus monkeys and Hominoids in the importance of configural cues and their ability to individuate conspecifics' faces, suggesting a lack of face expertise in rhesus monkeys. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Presentation-time measures of the effects of manipulations in colour space on discrimination of famous faces

Caricaturing the distinctive shape of famous faces can produce an advantage in reaction-time paradigms but the role of distinctive colour and intensity information in recognition of facial identity has not previously been explored. A presentation-time paradigm was developed by which stimuli could be presented for a range of brief display periods. Subjects were required to identify photo-realistic colour representations of famous faces which either were veridical, were caricatured in colour space, or had enhanced colour saturation and intensity contrast (as contrast controls). Recognition accuracy was greater when viewing the caricatured stimuli than either the veridical images or the contrast controls. The removal of colour information to produce grey-scale images also decreased accuracy of face recognition. Both results indicate that colour information aids differentiation of a class of natural stimuli with similar configurations. Thus it is demonstrated that caricaturing faces can be extended to the colour domain and, as with shape caricaturing, enhancement of distinctive information can produce a recognition advantage for famous faces.     

An experimental test of schema interaction.

"In an attempt to test propositions about the interaction of schemata, three stimuli, incidental to the stimulus to be rated, were paired with three supraliminal faces in a partly balanced design. Twenty-three subjects rated the stimuli and faces initially on an Osgood Semantic Differential. In a second session, several months later, they rated each face again, preceded by one of the objects below the level of focal awareness. It was predicted that the object and face schemata aroused by the first rating would be reactivated, and would interact in a predictable way to produce a new rating of the face. For two of the three types of objects, ratings of the face following the negative and control incidental stimuli moved in the direction of the object rating, in support of the hypothesis. The findings were discussed in terms of a theory of incidental schemata that influence ongoing cognition." From Psyc Abstracts 36:04:4CM11S. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Face Recognition Is Affected by Similarity in Spatial Frequency Range to a Greater Degree Than Within-Category Object Recognition.

Previous studies have suggested that face identification is more sensitive to variations in spatial frequency content than object recognition, but none have compared how sensitive the 2 processes are to variations in spatial frequency overlap (SFO). The authors tested face and object matching accuracy under varying SFO conditions. Their results showed that object recognition was more robust to SFO variations than face recognition and that the vulnerability of faces was not due to reliance on configural processing. They suggest that variations in sensitivity to SFO help explain the vulnerability of face recognition to changes in image format and the lack of a middle-frequency advantage in object recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Holistic processing of faces: Perceptual and decisional components.

Researchers have used several composite face paradigms to assess holistic processing of faces. In the selective attention paradigm, participants decide whether one face part (e.g., top) is the same as a previously seen face part. Their judgment is affected by whether the irrelevant part of the test face is the same as or different than the relevant part of the study face. This failure of selective attention implies holistic processing. However, the authors show that this task alone cannot distinguish between perceptual and decisional sources of holism. The distinction can be addressed by the complete identification paradigm, in which both face parts are judged to be same or different, combined with analyses based on general recognition theory (F. G. Ashby & J. T. Townsend, 1986). The authors used a different paradigm, sequential responses, to relate these 2 paradigms empirically and theoretically. Sequential responses produced the same results as did selective attention and complete identification. Moreover, disruptions of holistic processing by systematic misalignment of the faces corresponded with systematic and significant changes in the decisional components, but not in the perceptual components, that were extracted using general recognition theory measures. This finding suggests a significant decisional component of holistic face processing in the composite face task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The time course of repetition effects for words and unfamiliar faces.

The repetition effect on reaction time to words and unfamiliar faces was examined at lags of 0, 4, and 15 items between 1st and 2nd presentations. For words, Ss made either a lexical decision or a decision based on the stimulus's structural attributes. In the lexical decision task, a significant repetition effect was found at all 3 lags for words, whereas for nonwords the effect was significant only at Lag 0. In the structural decision task, the repeated decision was facilitated for both words and nonwords only at Lag 0, despite a word superiority effect at all lags. Target faces were presented either 0, 1, or 5 times before testing. Ss made either structural discriminations (face/nonface) or recognition judgments. In the structural discrimination task, the effect of repetition was significant only at Lag 0 (regardless of the number of pretest presentations). In the recognition task, the repetition effect was longer lasting, and its magnitude increased with the number of presentations which, presumably, determined the strength of the episodic memory trace. These results are taken as showing that repetition effects, like other measures of memory, are influenced by the type of stimulus, its preexperimental history, the level to which it is processed, and the lag between the initial presentation and the test. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Covert face recognition in prosopagnosia: a dissociable function?

Covert face recognition was investigated in a patient with prosopagnosia without object agnosia. This patient performed well in various face processing tasks like expression analysis and feature processing and had relatively preserved semantic knowledge about persons, but was slightly impaired in the visual matching of unfamiliar faces. In face-name paired-associate relearning task, covert face recognition was demonstrated to be above-chance. However, as this task cannot be meaningfully applied to control subjects, results do not necessarily indicate that the degree of covert face recognition is normal. In fact, in contrast to control subjects, the patient showed significantly reduced associative priming of names by face primes as compared to name primes, suggesting a quantitative reduction of covert face recognition. It is argued that these results support the view that overt and covert face recognition are brought about by the same functional system (Farah, O'Reilly and Vecera, 1993).