Assessment of calibration for reconstructed eye-witness memories

Two experiments examined confidence judgments associated with eyewitness memory for events to misinformation [Loftus, E. F. (1975). Leading questions and the eyewitness report. Cognitive Psychology, 7, 560-572]. Participants in each experiment watched videos depicting crimes and either responded to questionnaires (Experiment 1) or read narratives (Experiment 2) containing veridical or non-veridical information. Upon testing for memory performance 24 h later, participants exposed to misinformation accepted the misinformation as part of their memory of the events in the videos. In both experiments, confidence judgments of participants subjected to misinformation were high and comparable to those of participants not subjected to misinformation. The relationship between accurate responding and confidence was assessed via calibration analysis [Yates, J. F. (1990). Judgments and decision making. Englewood Cliffs, NJ: Prentice Hall]. Performance on various measures of calibration was generally better for participants who were not exposed to misinformation. We conclude that confidence judgments can depend on factors other than those that improve the accuracy of memory, such as the retrieval fluency of one’s memories.     

Factors in teachers' ratings of schoolchildren: Heymans' data reconstructed by modern standards

In this article we re-analyse the data that Heymans and Wiersma collected on pupils from secondary schools, about 80 years ago. The main interest is in the structure of the adolescence data set in terms of modern standards and understood against the background of recent findings. More specifically, one question is whether the Heymans data can be understood in terms of the framework of the Big Five structure of personality traits. To that end, principal components analysis and multiple group analysis were performed. The general conclusion from these analyses is that the adolescence data are best described by a two-dimensional structure. Another more specific research question is to what extent Heymans' own three dimensions can be detected in the data set. With emphasis on a small number of criterion items, used by Heymans to identify the three dimensions, a three-factor solution was inspected for this purpose. The conclusion from this analysis is that the three Heymans dimensions cannot unequivocally be identified in the adolescence data set.     

Effects of family interaction on the child's behavior in single-parent or reconstructed families

The effects of the family interaction on children's behavior were studied in single-parent or reconstructed families (N = 63) in a white population in Finland. The focus was on the spousal and the parent-child interaction. Teachers assessed children's behavior and parents were interviewed. The interviews were analyzed qualitatively using the grounded-theory method. The boundary ambiguity theory developed by Pauline Boss was used to examine the interaction in the families. About two fifths of the parents reported that their spousal interaction was good, family boundaries were clear, and the children were taken care of together. Another two fifths interacted only because of the child and family boundaries were ambiguous. In 14 families the involvement of the noncustodial parent was both physically and psychologically low. The physically close but psychologically distant parent-child interaction seemed to affect the child's behavior detrimentally, whereas children with physically and psychologically close interaction with their parents showed less behavioral problems. The children with behavioral problems were more likely to have problems with both parents. They were also more likely to have a stepparent with whom they had conflicts. In conclusion, a good interaction between the parents and clarified family boundaries protect children's mental health after their parents' divorce or separation.     

Reproducibility and variability of the cost functions reconstructed from experimental recordings in multifinger prehension

The study examines whether the cost functions reconstructed from experimental recordings are reproducible over time. Participants repeated the trials on three days. By following Analytical Inverse Optimization procedures, the cost functions of finger forces were reconstructed for each day. The cost functions were found to be reproducible over time: application of a cost function C(i) to the data of Day j (i≠j) resulted in smaller deviations from the experimental observations than using other commonly used cost functions. Other findings are: (a) the 2nd order coefficients of the cost function showed negative linear relations with finger force magnitudes; (b) the finger forces were distributed on a 2-dimensional plane in the 4-dimensional finger force space for all subjects and all testing sessions; (c) the data agreed well with the principle of superposition, i.e. the action of object prehension can be decoupled into the control of rotational equilibrium and slipping prevention.     

Color spaces of color-normal and color-abnormal observers reconstructed from response times and dissimilarity ratings

With multidimensional scaling analysis, color spaces were reconstructed from reaction times (RTs) required to make same-different judgements of pairs of 15 equiluminant colors and from dissimilarity ratings between them. In addition to normal trichromats, observers with red-green color deficiency were tested. Two main purposes were served by this study: (1) to compare spatial representations of colors derived from discriminative RTs with those derived from dissimilarity measures and (2) to examine whether the task may selectively affect the dimension reflecting, in color-abnormal spaces, the deficient red-green mechanism. Contradicting our hypothesis of lower dimensionality of RT spaces, as compared with rating spaces, no consistent differences in solution dimensionality were found. However, configurations derived from the two measures diverged. The rating procedure yielded the most logical results for recovering color space. The RT configuration revealed contraction in the tritanopic direction, indicating longer color processing when the short-wavelength mechanism is involved, and in addition, for color-abnormal observers, clustering in the protanopic and deuteranopic directions, indicating even longer processing by the deficient red-green mechanism. This finding implies that RTs are suitable for detecting temporal differences in color processing but, for that very same reason, rather ill-suited for reconstructing color spaces.     

Crossmodal visual-tactile extinction: Modulation by posture implicates biased competition in proprioceptively reconstructed space

Extinction is a common consequence of unilateral brain injury: contralesional events can be perceived in isolation, yet are missed when presented concurrently with competing events on the ipsilesional side. This can arise crossmodally, where a contralateral touch is extinguished by an ipsilateral visual event. Recent studies showed that repositioning the hands in visible space, or making visual events more distant, can modulate such crossmodal extinction. Here, in a detailed single-case study, we implemented a novel spatial manipulation when assessing crossmodal extinction. This was designed not only to hold somatosensory inputs and hand/arm-posture constant, but also to hold (retinotopic) visual inputs constant, yet while still changing the spatial relationship of tactile and visual events in the external world. Our right hemisphere patient extinguished left-hand touches due to visual stimulation of the right visual field (RVF) when tested in the usual default posture with eyes/head directed straight ahead. But when her eyes/head were turned to the far left (and any visual events shifted along with this), such that the identical RVF retinal stimulation now fell at the same external location as the left-hand touch, crossmodal extinction was eliminated. Since only proprioceptive postural cues could signal this changed spatial relationship for the critical condition, our results show for the first time that such postural cues alone are sufficient to modulate crossmodal extinction. Identical somatosensory and retinal inputs can lead to severe crossmodal extinction, or none, depending on current posture.