Papers by Markus Bindemann
Vision Research, 2011
The identification of unfamiliar faces has been studied extensively with matching tasks, in which... more The identification of unfamiliar faces has been studied extensively with matching tasks, in which observers decide if pairs of photographs depict the same person (identity matches) or different people (mismatches). In experimental studies in this field, performance is usually self-paced under the assumption that this will encourage best-possible accuracy. Here, we examined the temporal characteristics of this task by limiting display times and tracking observers' eye movements. Observers were required to make match/mismatch decisions to pairs of faces shown for 200, 500, 1000, or 2000 ms, or for an unlimited duration. Peak accuracy was reached within 2000 ms and two fixations to each face. However, intermixing exposure conditions produced a context effect that generally reduced accuracy on identity mismatch trials, even when unlimited viewing of faces was possible. These findings indicate that less than 2 s are required for face matching when exposure times are variable, but temporal constraints should be avoided altogether if accuracy is truly paramount. The implications of these findings are discussed.
Acta Psychologica, 2011
Research on sex differences in face recognition has reported mixed results, on balance suggesting... more Research on sex differences in face recognition has reported mixed results, on balance suggesting an advantage for female observers. However, it is not clear whether this advantage is specific to face processing or reflects a more general superiority effect in episodic memory. The current study therefore examined sex differences with a face-matching task that eliminates memory demands. Across two experiments, female but not male observers showed an own-sex advantage on match trials, in which two pictures have to be identified as the same person. This advantage was present for whole faces and when only the internal or external facial features were shown. Female observers were also more accurate in these three conditions on mismatch encounters, in which two photographs have to be identified as different people, but this reflects a more general effect that is present for male and female faces. These findings converge with claims of a female advantage in face recognition and demonstrate that this effect persists when memory demands are eliminated.
Perception, 2009
Five experiments are reported in which the relative importance of internal and external features ... more Five experiments are reported in which the relative importance of internal and external features for unfamiliar face identification are examined by a matching task. In experiments 1-3, Egyptian adults showed a robust internal-feature advantage for matching photographs of Egyptian faces. In experiment 4, a cross-cultural comparison between the ability of Egyptian and British adults to match the internal and external features of unfamiliar Egyptian and British faces was made. Once again, Egyptians showed an internal-feature advantage, for all faces. In contrast, British observers and also Egyptian children in experiment 5--showed external-feature advantages consistent with previous research. We attribute this contrast to the long-term experience of Egyptians in perceiving and recognising faces with headscarves, which might develop more expertise in processing the internal than the external features of unfamiliar faces.
Vision Research, 2010
In laboratory studies of visual perception, images of natural scenes are routinely presented on a... more In laboratory studies of visual perception, images of natural scenes are routinely presented on a computer screen. Under these conditions, observers look at the center of scenes first, which might reflect an advantageous viewing position for extracting visual information. This study examined an alternative possibility, namely that initial eye movements are drawn towards the center of the screen. Observers searched visual scenes in a person detection task, while the scenes were aligned with the screen center or offset horizontally (Experiment 1). Two central viewing effects were observed, reflecting early visual biases to the scene and the screen center. The scene effect was modified by person content but is not specific to person detection tasks, while the screen bias cannot be explained by the low-level salience of a computer display (Experiment 2). These findings support the notion of a central viewing tendency in scene analysis, but also demonstrate a bias to the screen center that forms a potential artifact in visual perception experiments.
Experimental Psychology, 2007
There is evidence that face processing is capacity-limited in distractor interference tasks and i... more There is evidence that face processing is capacity-limited in distractor interference tasks and in tasks requiring overt recognition memory. We examined whether capacity limits for faces can be observed with a more sensitive measure of visual processing, by measuring repetition priming of flanker faces that were presented alongside a face or a nonface target. In Experiment 1, we found identity priming for face flankers, by measuring repetition priming across a change in image, during task-relevant nonface processing, but not during the processing of a concurrently-presented face target. Experiment 2 showed perceptual priming of the flanker faces, across identical images at prime and test, when they were presented alongside a face target. In a third Experiment, all of these effects were replicated by measuring identity priming and perceptual priming within the same task. Overall, these results imply that face processing is capacity limited, such that only a single face can be identified at one time. Merely attending to a target face appears sufficient to trigger these capacity limits, thereby extinguishing identification of a second face in the display, although our results demonstrate that the additional face remains at least subject to superficial image processing.
Vision Research, 2009
The ability to detect faces in visual scenes is little understood. Across three experiments we ex... more The ability to detect faces in visual scenes is little understood. Across three experiments we examined whether particular facial views (for example those revealing a pair of eyes) facilitate detection while observers are searching for faces in complex visual scenes. Viewers' performance was equivalent for faces shown in frontal and mid-profile pose, but declined in profile (Experiment 1). These differences persisted when only half the face was shown, so that one eye was visible in frontal and profile view but both eyes were preserved in mid-frontal faces (Experiment 2). The same pattern was found when only the upper region of a face appeared in visual scenes, but the presentation of lower half faces eliminated all differences (Experiment 3). These findings demonstrate that the upper face mediates detection across different views, but 'a pair of eyes' cannot explain differences in detectability.
Vision Research, 2008
When faces are turned upside-down, many aspects of face processing are severely disrupted. Here w... more When faces are turned upside-down, many aspects of face processing are severely disrupted. Here we report an instance where this face inversion effect is not found. In a visual cueing paradigm an inverted face was paired with an inverted object in a cue display, followed by a target in one of the cue locations (Experiment 1). Responses were faster to face-cued targets, indicating an attention bias for inverted faces. When upright and inverted face cues were paired in Experiment 2, no attention bias for either cue type was found, suggesting that attention was drawn equally to both types of stimuli. Despite this, attention could be biased selectively toward upright or inverted faces in Experiment 3, by manipulating the predictiveness of either type of cue, which shows that observers can distinguish upright and inverted faces under these conditions. A fourth experiment provided a replication of Experiment 2 with an extended stimulus set and increased task demands. These findings suggest that visual attributes that can influence the allocation of an observer's attention to faces are available in both upright and inverted orientations.
Cognition, 2005
We present three experiments in which subjects were asked to make speeded sex judgements (Experim... more We present three experiments in which subjects were asked to make speeded sex judgements (Experiment 1) or semantic judgements (Experiments 2 and 3) to face targets and nonface items, while ignoring a solitary flanking distractor face or a nonface stimulus. Distractors could be either congruent (same response category) or incongruent (different response category) with the target. Distractor congruency effects were consistently observed in all combinations of target-distractor stimulus pairs, except when a distractor face flanked a target face. The failure to find congruency effects in this condition was explored further in a fourth experiment, in which four task-irrelevant flankers were simultaneously presented. Once again, no face-face congruency effects were found, even though comparison distractors interfered with face and nonface targets alike. However, four simultaneously presented distractor faces did not interfere with nonface targets either. We suggest that these experiments demonstrate a capacity limit for visual processing in these conditions, such that no more than one face is processed at a time.
Psychonomic Bulletin & Review, 2005
In the present study, we investigated whether faces have an advantage in retaining attention over... more In the present study, we investigated whether faces have an advantage in retaining attention over other stimulus categories. In three experiments, subjects were asked to focus on a central go/no-go signal before classifying a concurrently presented peripheral line target. In Experiment 1, the go/no-go signal could be superimposed on photographs of upright famous faces, matching inverted faces, or meaningful objects. Experiments 2 and 3 tested upright and inverted unfamiliar faces, printed names, and another class of meaningful objects in an identical design. A fourth experiment provided a replication of Experiment 1, but with a 1,000-msec stimulus onset asynchrony between the onset of the central face/nonface stimuli and the peripheral targets. In all the experiments, the presence of an upright face significantly delayed target response times, in comparison with each of the other stimulus categories. These results suggest a general attentional bias, so that it is particularly difficult to disengage processing resources from faces.
Cognitive Science, 2009
Significant advances have been made in understanding human face recognition. However, a fundament... more Significant advances have been made in understanding human face recognition. However, a fundamental aspect of this process, how faces are located in our visual environment, is poorly understood and little studied. Here we examine the role of color in human face detection. We demonstrate that detection performance declines when color information is removed from faces, regardless of whether the surrounding scene context is rendered in color. Furthermore, faces rendered in unnatural colors are hard to detect, suggesting a role beyond simple segmentation. When faces are presented such that half the surface is colored appropriately, and half unnaturally, performance declines. This suggests that observers are not simply using the presence of skin color “patches” to detect faces. Rather, our data suggest that detection operates via a face template combining diagnostic color and face-shape information. These findings are consistent with color-template approaches used in some computer-based face detection systems.
Journal of Experimental Psychology-human Perception and Performance, 2010
Person detection is an important prerequisite of social interaction, but is not well understood. ... more Person detection is an important prerequisite of social interaction, but is not well understood. Following suggestions that people in the visual field can capture a viewer's attention, this study examines the role of the face and the body for person detection in natural scenes. We observed that viewers tend first to look at the center of a scene, and only then to fixate on a person. When a person's face was rendered invisible in scenes, bodies were detected as quickly as faces without bodies, indicating that both are equally useful for person detection. Detection was optimized when face and body could be seen, but observers preferentially fixated faces, reinforcing the notion of a prominent role for the face in social perception. These findings have implications for claims of attention capture by faces in that they demonstrate a mediating influence of body cues and general scanning principles in natural scenes.
Journal of Experimental Psychology-human Perception and Performance, 2009
The direction of another person&a... more The direction of another person's gaze is difficult to ignore when presented at the center of attention. In 6 experiments, perception of unattended gaze was investigated. Participants made directional (left-right) judgments to gazing-face or pointing-hand targets, which were accompanied by a distractor face or hand. Processing of the distractor was assessed via congruency effects on target response times. Congruency effects were found from the direction of distractor hands but not from the direction of distractor gazes (Experiment 1). This pattern persisted even when distractor sizes were increased to compensate for their peripheral presentation (Experiments 2 and 5). In contrast, congruency effects were exerted by profile heads (Experiments 3 and 4). In Experiment 6, isolated eye region distractors produced no congruency effects, even when they were presented near the target. These results suggest that, unlike other facial information, gaze direction cannot be perceived outside the focus of attention.
Visual Cognition, 2008
Previous research has demonstrated an interaction between eye gaze and selected facial emotional ... more Previous research has demonstrated an interaction between eye gaze and selected facial emotional expressions, whereby the perception of anger and happiness is impaired when the eyes are horizontally averted within a face, but the perception of fear and sadness is enhanced ...
Psychophysiology, 2008
The N250r is an event-related potential that has been related to activation of image-independent ... more The N250r is an event-related potential that has been related to activation of image-independent representations of familiar faces during recognition. However, N250r also shows a degree of image specificity, with reduced activation across repetitions of different images of the same face compared to repetitions across the same image, suggesting a component that codes the visual overlap between two face images. This study investigated whether N250r is equally attenuated when horizontally or vertically stretched faces prime an unstretched image of the same face. The results confirm that N250r is larger across repetitions of the same face image than across different images of the same face. Despite this, N250r was equivalent for priming by the same face image and priming from stretched onto unstretched faces. This finding demonstrates that N250r does not simply reflect the superficial visual overlap between two face images and supports the notion that it is related to person recognition.
Journal of Vision, 2007
Humans attend to faces. This study examines the extent to which attention biases to faces are und... more Humans attend to faces. This study examines the extent to which attention biases to faces are under top-down control. In a visual cueing paradigm, observers responded faster to a target probe appearing in the location of a face cue than of a competing object cue (Experiments 1a and 2a). This effect could be reversed when faces were negatively predictive of the likely target location, making it beneficial to attend to the object cues (Experiments 1b and 2b). It was easier still to strategically shift attention to predictive face cues (Experiment 2c), indicating that the endogenous allocation of attention was augmented here by an additional effect. However, faces merely delayed the voluntary deployment of attention to object cues, but they could not prevent it, even at short cue-target intervals. This finding suggests that attention biases for faces can be rapidly countered by an observer's endogenous control.
Journal of Vision, 2009
In everyday life, human faces are encountered in many different views. Despite this fact, most ps... more In everyday life, human faces are encountered in many different views. Despite this fact, most psychological research has focused on the perception of frontal faces. To address this shortcoming, the current study investigated how different face views are processed, by measuring eye movements to frontal, mid-profile and profile faces during a gender categorization (Experiment 1) and a free-viewing task (Experiment 2). In both experiments observers initially fixated the geometric center of a face, independent of face view. This center-of-gravity effect induced a qualitative shift in the features that were sampled across different face views in the time period immediately after stimulus onset. Subsequent eye fixations focused increasingly on specific facial features. At this stage, the eye regions were targeted predominantly in all face views, and to a lesser extent also the nose and the mouth. These findings show that initial saccades to faces are driven by general stimulus properties, before eye movements are redirected to the specific facial features in which observers take an interest. These findings are illustrated in detail by plotting the distribution of fixations, first fixations, and percentage fixations across time.
Uploads
Papers by Markus Bindemann