The role of holistic face processing in acquired prosopagnosia: evidence from the composite face effect

Faces are processed more holistically than other objects, and it has been suggested that the loss of holistic face processing causes acquired prosopagnosia. Support for this hypothesis comes from several cases who failed to show holistic face effects as well as the absence of reports of prosopagnosics with unequivocally normal holistic face perception. The current study examines the relationship between holistic face processing and prosopagnosia by testing seven acquired prosopagnosics with the face composite task, a classic measure of holistic face processing. To enhance the robustness of the findings, each prosopagnosic was tested with two versions of the composite task showing upright faces. We also tested an inverted condition to exclude the possibility that more general factors account for composite effects for upright faces. Four of the seven acquired prosopagnosic participants showed consistent upright face composite effects with minimal inverted face composite effects. We conclude that severe face processing deficits can co-occur with intact holistic face processing and that factors other than a loss of holistic processing contribute to the perceptual and recognition deficits in acquired prosopagnosia.     

RETRACTED ARTICLE: Unexpected events disrupt visuomotor working memory and increase guessing

When an unexpected event, such as a car horn honking, occurs in daily life, it often disrupts our train of thought. In the lab, this effect was recently modeled with a task in which verbal working memory (WM) was disrupted by unexpected auditory events (Wessel et al. in Nature Communications, 7, 11195, 2016). Here we tested whether this effect extends to a different type of WM—namely, visuomotor. We found that unexpected auditory events similarly decremented visuomotor WM. Moreover, this effect persisted for many more trials than had previously been shown for verbal WM, and the effect occurred for two different types of unexpected auditory events. Furthermore, we found that unexpected events decremented WM by decreasing the quantity, but not necessarily the quality, of items stored. These results showed an impact of unexpected events on visuomotor WM that was statistically robust and endured across time. They also showed that the effect was based on an increase in guessing, consistent with a neuroscience-inspired theory that unexpected events “wipe out” WM by stopping the ongoing maintenance of the trace. This new task paradigm is an excellent vehicle for further explorations of distractibility.     

Development and validation of a brief self-report measure of trauma exposure: the Trauma History Screen

Although information about individuals' exposure to highly stressful events such as traumatic stressors is often very useful for clinicians and researchers, available measures are too long and complex for use in many settings. The Trauma History Screen (THS) was developed to provide a very brief and easy-to-complete self-report measure of exposure to high magnitude stressor (HMS) events and of events associated with significant and persisting posttraumatic distress (PPD). The measure assesses the frequency of HMS and PPD events, and it provides detailed information about PPD events. Test-retest reliability was studied in four samples, and temporal stability was good to excellent for items and trauma types and excellent for overall HMS and PPD scores. Comprehensibility of items was supported by expert ratings of how well items appeared to be understood by participants with relatively low reading levels. In five samples, construct validity was supported by findings of strong convergent validity with a longer measure of trauma exposure and by correlations of HMS and PPD scores with posttraumatic stress disorder (PTSD) symptoms. The psychometric properties of the THS appear to be comparable or better than longer and more complex measures of trauma exposure.     

The effects of dynamic assessment procedures on Raven Matrices performance,visual search behavior,test anxiety and test orientation

The effects of dynamic testing procedures on Raven Coloured Matrices performance, visual scanning procedures, test anxiety, and orientation to the test situation were assessed. The subjects were 72 third-grade children. The results supported the hypotheses of the study showing that (1) dynamic assessment procedures involving either verbalization or elaborated feedback lead to higher levels of Raven Matrices performance; that (2) dynamic assessment modifies visual search behaviors; and that (3) dynamic assessment reduces test anxiety and negative orientation to the testing situation. The results are interpreted as offering construct validation to the assessment approaches used.