Malte Persike

Differences in agency? How adolescents from 18 countries perceive and cope with their futures

This study investigated how N = 5,126 adolescents (mean age of 15 years) from 18 countries perceive and cope with future- and school-related stress. The adolescents completed the Problem Questionnaire (PQ), which assesses stress, and the Coping Across Situations Questionnaire (CASQ), which assesses three coping styles (reflection/support-seeking, emotional outlet, and withdrawal/denial). Across countries, adolescents reported considerably higher levels of future-related stress than school-related stress. The adolescents actively coped with stressors in both domains and seldom relied on emotional outlet or withdrawal/denial. A clustering of the countries according to socioeconomic criteria and geographical proximity demonstrated that adolescents from the continental group of countries showed low stress and high coping. Adolescents in the east/Asia group showed medium stress and low coping and those in the south group showed high stress and low coping. Developmental context was more strongly associated with stress perception and coping, style than age or gender, a finding relevant for prevention approaches aiming to endorse positive orientation to the future and improve coping competence.

The time course of face matching by internal and external features: Effects of context and inversion.

Effects of context and inversion were studied in face matching tasks by measuring proportion correct as a function of exposure duration. Subjects were instructed to attend either internal features (task A) or external features (task B) and matched two consecutive face stimuli, which included either congruent, incongruent, or no facial context features. In congruent contexts matching performance rose fast and took very similar courses for both types of facial features. With no contexts internal and external features were found to be matched at an equal speed, while incongruent contexts seriously delayed matching performance for internal, but not for external features. Analysing the effects of context and inversion showed strong interactions with time scale and the features to be attended. At brief timings effects of inversion and context were strong for both feature types. At longer exposure durations there were pronounced effects of inversion and context for internal features while for external features inversion effects were absent and context effects at just moderate degrees. Moreover, deteriorating effects of incongruent contexts, which were strong at brief timings, were attenuated at longer exposure durations, while facilitative effects of congruent contexts resided at high levels. These findings indicate that global and holistic processing modes dominate the early epoch of the face specific visual response, but can be replaced by modes that allow observers to regulate contextual influences and to access facial features more focused when the first 200 ms have passed.

Stress with parents and peers: how adolescents from 18 nations cope with relationship stress

Background and Objectives: We investigated how adolescents from five regions around the world perceived and coped with parent- and peer-related stress. Design: The study comprised N = 4957 adolescents (mean age of 15.2 years) from 18 countries. Methods: The study used self-report measures for stress perception and coping style. Results: Across countries, adolescents perceived parent-related stress to be considerably greater than peer-related stress. They coped less actively with parent-related stress than with peer-related stress. Significant differences emerged with respect to geographic region and key demographic indicators. Adolescents from Eastern European and Western countries had generally quite low levels of stress. Adolescents from Southern Europe exhibited the highest stress levels and the greatest coping activity in dealing with stress in both domains, whereas adolescents from Southern Emerging and Asian countries reported high levels of parent-related stress and dealt much less actively with parent-related stress than with peer-related stress. Conclusions: Adolescents from all countries were remarkably competent in dealing with relationship stressors. Cultural and regional differences have a stronger effect on stress perception and coping style than gender.

Cue combination in a combined feature contrast detection and figure identification task

Target figures defined by feature contrast in spatial frequency, orientation or both cues had to be detected in Gabor random fields and their shape had to be identified in a dual task paradigm. Performance improved with increasing feature contrast and was strongly correlated among both tasks. Subjects performed significantly better with combined cues than with single cues. The improvement due to cue summation was stronger than predicted by the assumption of independent feature specific mechanisms, and increased with the performance level achieved with single cues until it was limited by ceiling effects. Further, cue summation was also strongly correlated among tasks: when there was benefit due to the additional cue in feature contrast detection, there was also benefit in figure identification. For the same performance level achieved with single cues, cue summation was generally larger in figure identification than in feature contrast detection, indicating more benefit when processes of shape and surface formation are involved. Our results suggest that cue combination improves spatial form completion and figure-ground segregation in noisy environments, and therefore leads to more stable object vision.

Holistic processing and reliance on global viewing strategies in older adults' face perception

There is increasing evidence that face recognition might be impaired in older adults, but it is unclear whether the impairment is truly perceptual, and face specific. In order to address this question we compared performance in same/different matching tasks with face and non-face objects (watches) among young (mean age 23.7) and older adults (mean age 70.4) using a context congruency paradigm (Meinhardt-Injac, Persike & Meinhardt, 2010, Meinhardt-Injac, Persike and Meinhardt, 2011a). Older adults were less accurate than young adults with both object classes, while face matching was notably impaired. Effects of context congruency and inversion, measured as the hallmarks of holistic processing, were equally strong in both age groups, and were found only for faces, but not for watches. The face specific decline in older adults revealed deficits in handling internal facial features, while young adults matched external and internal features equally well. Comparison with non-face stimuli showed that this decline was face specific, and did not concern processing of object features in general. Taken together, the results indicate no age-related decline in the capabilities to process faces holistically. Rather, strong holistic effects, combined with a loss of precision in handling internal features indicate that older adults rely on global viewing strategies for faces. At the same time, access to the exact properties of inner face details becomes restricted.

The context effect in face matching: Effects of feedback

Faces are perceived holistically, even when they are presented briefly (Hole, 1994; Richler, Mack, et al., 2009). Results obtained with a context congruency paradigm support dominance of holistic processing for brief timings, but indicate that larger viewing times enable observers to regulate contextual influences, and to use a feature selective focus (Meinhardt-Injac, Persike, & Meinhardt, 2010). Here we provide further evidence for this claim, and illuminate the role of feedback. With trial by trial feedback observers show poor performance in incongruent facial contexts at brief timings, but become quite effective in suppressing information that interferes with the correct judgements at larger viewing times. Without feedback they are still able to delimit the effects of conflicting contextual information, but are less effective. Adding further target features leads to moderate performance increase in incongruent contexts when there is no feedback, but to strong improvement when feedback is provided. These findings indicate that observers use opportunities of learning to replace holistic face perception by modes of active vision when sufficient temporal resources are available.

Feature synergy depends on feature contrast and objecthood

Pairs of texture figures, defined by contrast in spatial frequency, orientation or both cues (redundant texture definition) had to be detected within a homogeneous Gabor field. In line with expectation we find better detection performance for arrangements with higher feature contrast along the border where the figures abut. Redundantly defined figures show synergy, a significant performance increase compared to the prediction of independent processing of orientation and spatial frequency cues. As found in previous studies [Spatial Vision 16 (2003) 459; Vision Research (submitted for publication)] this performance advantage is negatively correlated with visibility. In particular, figures with high border feature contrast are easily detectable but show weak synergy whereas figures with low border feature contrast are barely detectable but remarkably benefit from redundant texture definition. Closer analysis reveals that the form of the figures is also crucial: As long as they maintain a clear two dimensional shape the synergy effect is only marginally affected by variation figure size and border length. But when they degrade to one dimensional Gabor element arrays, synergy almost completely vanishes. The results imply that both factors, low visibility and objecthood, are critical for feature synergy. We conclude that facilitation across feature domains serves to segregate figure from ground when the signal from a single domain is too weak to enable object detection and vanishes under conditions of stable object vision.

Synergy of features enables detection of texture defined figures

Traditional theories of early visual processing suggest that elementary visual features are handled in parallel by independent neural pathways. We studied the interaction of orientation and spatial frequency in the discrimination of Gabor random fields. Target textures differed from reference textures either in mean feature value, showing an edge-like transition between both textures (edge defined), or in the degree of feature homogeneity with smooth transitions (region defined). Irrespective of the kind of texture definition, we found strong cue summation for targets defined by both cues simultaneously, provided two conditions were fulfilled. First, they were barely discriminable when defined by one cue alone. Second, the target elements formed a closed 2D surface. Only marginal cue summation was observed when target elements were heterogeneously distributed in a predefined area, lacking a clear 2D shape. Our findings indicate that feature synergy enables figure-ground segregation when the information from independent feature-specific pathways is insufficient for solving this task.

Strength of feature contrast mediates interaction among feature domains

Traditional theories of texture segregation suggest that elementary visual features are processed in parallel by independent modules at early visual stages. Here we show that, for small feature contrasts and large values evoking perceptual popout, different forms of module interaction exist. While discrimination of highly salient features rests on independent feature specific pathways, information is summed across domains when barely noticeable ones are to be detected in homogeneous textures.

The complete design in the composite face paradigm: role of response bias, target certainty, and feedback

Some years ago an improved design (the “complete design”) was proposed to assess the composite face effect in terms of a congruency effect, defined as the performance difference for congruent and incongruent target to no-target relationships (Cheung et al., 2008). In a recent paper Rossion (2013) questioned whether the congruency effect was a valid hallmark of perceptual integration, because it may contain confounds with face-unspecific interference effects. Here we argue that the complete design is well-balanced and allows one to separate face-specific from face-unspecific effects. We used the complete design for a same/different composite stimulus matching task with face and non-face objects (watches). Subjects performed the task with and without trial-by-trial feedback, and with low and high certainty about the target half. Results showed large congruency effects for faces, particularly when subjects were informed late in the trial about which face halves had to be matched. Analysis of response bias revealed that subjects preferred the “different” response in incongruent trials, which is expected when upper and lower face halves are integrated perceptually at the encoding stage. The results pattern was observed in the absence of feedback, while providing feedback generally attenuated the congruency effect, and led to an avoidance of response bias. For watches no or marginal congruency effects and a moderate global “same” bias were observed. We conclude that the congruency effect, when complemented by an evaluation of response bias, is a valid hallmark of feature integration that allows one to separate faces from non-face objects.