An analysis of tactile letter confusions

A confusion matrix of the whole block capital letters of the alphabet was obtained so as to examine the nature of tactile letter recognition, using a 17 by 17 matrix of tactile stimulators placed against blind subjects’ backs. A hierarchical cluster analysis and a nonmetric multidimensional scaling technique were applied to the matrix. The results of the two analyses were consistent with each other and indicated that at least three independent basic letter features—enclosing shapes, vertical parallel lines, andangle of lines—play important parts in tactile letter recognition. Most confusion may be attributable to displacement of the apparent loci, omission or fusion of loci of stimulation, and failure to detect gaps in the tactile letters.     

Imagery ability and the identification of hands: A chronometric analysis

In a replication of Cooper and Shepard's (1975) study of hand recognition, it was found that individual differences in imagery ability had a significant influence on reaction times to such stimuli (Experiment 1). However, it was found (Experiment 2) that individual difference effects were only seen if prior instructions to use imagery were given to the subjects.     

Children's use of sequence information in partially predictable reaction-time sequences

Second-, fourth-, and sixth-grade children and adults performed a four-choice reaction time task with partially predictable sequences and 250-, 500-, and 750-msec response-to-stimulus intervals. The relative advantage for in-sequence as opposed to out-of-sequence events was independent of the response-to-stimulus interval for all ages. Children, but not adults, were slower for nonrepeated than repeated out-of sequence events and this advantage for repeated signals decreased as age increased. A second experiment extended the range of intervals tested to zero. Second graders and adults responded to four-choice partially predictable sequences with 0-, 250-, and 500-msec response-to-stimulus intervals. As in the first experiment, the difference between in-sequence and out-of-sequence events did not vary with the response-to-stimulus interval. The results suggest that both children and adults are able to process advance sequence probability information about a subsequent event in parallel with an ongoing response.     

Dissociating perceptual and representation-based contributions to priming of face recognition

Repetition priming of object identification refers to the phenomenon whereby experience with an object induces systematic changes in subsequent processing of that same object. This data-driven form of priming is distinct from conceptually-driven priming. To date, considerable controversy exists about whether data-driven priming reflects facilitation in perceptual processing or mediation by preexisting object representations. The present study concerned priming of recognizing familiar and unfamiliar faces and how this priming is influenced by face inversion, which interferes with perceptual face processing. Perceptual and representation-based loci conjointly contributed to priming; the perceptual locus was operative similarly for familiar and unfamiliar faces, whereas the representation-based locus was only invoked for familiar faces and resulted in a response-time reduction triple the magnitude of that from the perceptual locus. The results constrain theoretical accounts of data-driven priming by indicating that improved identification can result from the combination of perceptual and representation-based facilitation.     

Can subthreshold summation be observed with the Ehrenstein illusion?

Subthreshold summation between physical target lines and illusory contours induced by edges such as those produced in the Kanizsa illusion has been reported in previous studies. Here, we investigated the ability of line-induced illusory contours, using Ehrenstein figures, to produce similar subthreshold summation. In the first experiment, three stimulus conditions were presented. The target line was superimposed on the illusory contour of a four-arm Ehrenstein figure, or the target was presented between two dots (which replaced the arms of the Ehrenstein figure), or the target was presented on an otherwise blank screen (control). Detection of the target line was significantly worse when presented on the illusory contour (on the Ehrenstein figure) than when presented between two dots. This result was consistent for both curved and straight target lines, as well as for a 100 ms presentation duration and unlimited presentation duration. Performance was worst in the control condition. The results for the three stimulus conditions were replicated in a second experiment in which an eight-arm Ehrenstein figure was used to produce a stronger and less ambiguous illusory contour. In the third experiment, the target was either superimposed on the illusory contour, or was located across the central gap (illusory surface) of the Ehrenstein figure, collinear with two arms of the figure. As in the first two experiments, the target was either presented on the Ehrenstein figure, or between dots, or on a blank screen. Detection was better in the dot condition than in the Ehrenstein condition, regardless of whether the target was presented on the illusory contour or collinear with the arms of the Ehrenstein figure. These three experiments demonstrate the ability of reduced spatial uncertainty to facilitate the detection of a target line, but do not provide any evidence for subthreshold summation between a physical target line and the illusory contours produced by an Ehrenstein figure. The incongruence of these results with previous findings on Kanizsa figures is discussed.     

Subjective and objective measures of quality of life have different predictors for people with schizophrenia

This study investigated the relationship between subjective and objective quality of life and assessed predictors in people with schizophrenia. The study population consisted of 99 stabilized outpatients with schizophrenia (DSM-IV) who had been regularly receiving outpatient treatment at the Department of Psychiatry, The Tokushima University Hospital. Subjective and objective quality of life were estimated using the Schizophrenia Quality of Life Scale and the Quality of Life Scale, respectively. Psychiatric symptoms were also measured with the Brief Psychiatric Rating Scale and the Calgary Depression Scale for Schizophrenia. Scores on the Schizophrenia Quality of Life Scale Motivation and Energy scales significantly correlated with the Quality of Life Scale total scores -.40 (p <.001), and with the scores on Interpersonal Relations subscale -.42 (p <.001), Instrumental Role subscale -.28 (p = .005), Intrapsychic Foundations subscale -.39 (p<.001), and Common Objects and Activities subscale -.25 (p =.014). The Schizophrenia Quality of Life Scale Psychosocial scale significantly correlated with only the Quality of Life Scale total score -.20 (p =.05), and there was no significant correlation between the scores on the Schizophrenia Quality of Life Scale Symptoms and Side-effects scales and the Quality of Life Scale. Stepwise regression analyses showed that the Calgary Depression Scale for Schizophrenia score was the most important predictor of each scale of the Schizophrenia Quality of Life Scale, and the Brief Psychiatric Rating Scale Negative Symptoms score was the most important predictor of the Quality of Life Scale total score and each subscale. These results suggest that subjective and objective quality of life have different predictors and should be considered as separate and complementary outcome variables.     

Measuring the Intrapersonal Component of Psychological Empowerment: Confirmatory Factor Analysis of the Sociopolitical Control Scale

The Sociopolitical Control Scale (SPCS) is a widely used measure of the intrapersonal component of psychological empowerment. Confirmatory factor analyses (CFA) were conducted with data from two samples to test the hypothesized structure of the SPCS, the potential effects of method bias on the measure’s psychometric properties, and whether a revised version of the scale (SPCS-R) yielded improved model fit. Sample 1 included 316 randomly selected community residents of the Midwestern United States. Sample 2 included 750 community residents of the Northeastern U.S. Results indicated that method bias from the use of negatively worded items had a significant effect on the factor structure of the SPCS. CFA of the SPCS-R, in which negatively worded items were rephrased so that all statements were positively worded, supported the measure’s hypothesized two-factor structure (i.e., leadership competence and policy control). Subscales of the SPCS-R were found reliable and related in expected ways with measures of community involvement. Implications of the study for empowerment-based research and practice are described, and strategies to further develop the SPCS are discussed.     

An open letter to institutional review boards considering Northfield Laboratories' PolyHeme trial

At the time of this writing, a widely publicized, waived-consent trial is underway. Sponsored by Northfield Laboratories, Inc. (Evanston, IL) the trial is intended to evaluate the emergency use of PolyHeme, an oxygen-carrying resuscitative fluid that might prevent deaths from uncontrolled bleeding. The protocol allows patients in hemorrhagic shock to be randomized between PolyHeme and saline in the field and, still without consent, randomized between PolyHeme and blood after arrival at an emergency department. The Federal regulations that govern the waiver of consent restrict its applicability to circumstances where proven, satisfactory treatments are unavailable. Blood-the standard treatment for hemorrhagic shock-is not available in ambulances but is available in hospitals. The authors argue that the in-hospital stage of the study fails to meet ethical and regulatory standards.     

Remembering a nuclear accident in Japan: did it trigger flashbulb memories?

Flashbulb memories are vivid memories of the details surrounding the discovery of an emotional event. We investigated whether the nuclear accident that occurred in Japan in 1999 produced flashbulb memories among people who lived near the accident site. A questionnaire was distributed twice (approximately 3 weeks after the accident and 1 year later) to (1) the residents of the communities surrounding the accident site, (2) the students at a university near the accident site, and (3) the students at two universities far away from the accident site. Flashbulb memory holders were defined as those individuals who showed consistent memories between test and retest. The results indicated that only a small percentage of participants formed flashbulb memories. Further, no age-related decline was found. Flashbulb memories were distinguished by perfect or near perfect scores on four attributes: source, place, activity, and people. The results also indicated that the ratings on emotional reactions, personal consequentiality, and surprise did not differentiate between the flashbulb and non-flashbulb memory holders. In contrast, the flashbulb memory holders reported rehearsing more than the non-flashbulb memory holders. These results supported the notion that flashbulb memories are formed through rehearsal rather than at encoding. However, it is also possible that rehearsal was a result of the flashbulb memory.