The information content of panoramic images II: view-based navigation in nonrectangular experimental arenas

Two recent studies testing navigation of rats in swimming pools have posed problems for any account of the use of purely geometric properties of space in navigation (M. Graham, M. A. Good, A. McGregor, & J. M. Pearce, 2006; J. M. Pearce, M. A. Good, P. M. Jones, & A. McGregor, 2004). The authors simulated 1 experiment from each study in a virtual reality environment to test whether experimental results could be explained by view-based navigation. The authors recorded a reference image at the target location and then determined global panoramic image differences between this image and images taken at regularly spaced locations throughout the arena. A formal model, in which an agent attempts to minimize image differences between the reference image and current views, generated trajectories that could be compared with the search performance of rats. For both experiments, this model mimics many aspects of rat behavior. View-based navigation provides a sufficient and parsimonious explanation for a range of navigational behaviors of rats under these experimental conditions.     

Disgust as embodied moral judgment

How, and for whom, does disgust influence moral judgment? In four experiments participants made moral judgments while experiencing extraneous feelings of disgust. Disgust was induced in Experiment 1 by exposure to a bad smell, in Experiment 2 by working in a disgusting room, in Experiment 3 by recalling a physically disgusting experience, and in Experiment 4 through a video induction. In each case, the results showed that disgust can increase the severity of moral judgments relative to controls. Experiment 4 found that disgust had a different effect on moral judgment than did sadness. In addition, Experiments 2-4 showed that the role of disgust in severity of moral judgments depends on participants' sensitivity to their own bodily sensations. Taken together, these data indicate the importance-and specificity-of gut feelings in moral judgments.     

A fast numerical algorithm for the estimation of diffusion model parameters

In this paper, we describe a new algorithmic approach for parameter estimation in Ratcliff's [(1978). A theory of memory retrieval. Psychological Review, 85 (2), 59-108] diffusion model. This problem, especially if inter-trial variabilities of parameters are included in the model, is computationally very expensive; the parameter estimation procedure often takes a long time even with today's high-speed computers. The algorithm described here makes the calculation of the cumulative distribution functions for predicted process durations computationally much less expensive. This improvement is achieved by solving the Kolmogorov backward equation numerically instead of employing the previously used closed form solution. Additionally, the algorithm can determine the optimum fit for one of the model parameters (the starting point z) directly, thereby reducing the dimension of the parameter search space by one. The resulting method is shown to be notably faster than the standard (closed-form solution) method for parameter estimation.     

Observed Leadership Potential of Personnel in a Team Setting: Big Five traits and proximal factors as predictors

The authors explored implications of Big Five traits and proximal factors for the observed leadership potential of personnel in newly formed teams. Big Five traits were designated as distal factors having indirect links to observed leadership potential via three proximal factors: individual perception of team cohesion, team‐oriented proactivity, and teamwork knowledge. Drawing from implicit personality theory, the authors introduced a team‐leader personality profile as a higher‐order construct for explaining covariation among extraversion, conscientiousness, and emotional stability. A structural analysis of data from 472 personnel supported hypothesized relationships. Specific findings included validation of a team‐leader personality profile and preliminary support for the measure of team‐oriented proactivity that was developed for this study. Implications of the various findings are discussed.     

Brain lesion and memory functioning: Short-term memory deficit is independent of lesion location

We analyzed the effects of patterns of brain lesions from penetrating head injuries on memory performance in participants of the Vietnam Head Injury Study (Grafman et al., 1988). Classes of lesion patterns were determined by mixture modeling (L. K. Muthén & B. O. Muthén, 1998-2004). Memory performance was assessed for short-term memory (STM), semantic memory, verbal episodic memory, and visual episodic memory. The striking finding was that large STM deficits were observed in all classes of brain-injured individuals, regardless of lesion location pattern. These effects persist despite frequent concomitant effects of depressive symptomatology and substance dependence. Smaller deficits in semantic memory, verbal episodic memory, and visual episodic memory depended on lesion location, in a manner roughly consistent with the existing neuropsychological literature. The theoretical and clinical implications of the striking, seemingly permanent STM deficits in individuals with penetrating head injuries are discussed.     

Development of number combination skill in the early school years: when do fingers help?

Children's change over time in frequency of finger use on number combinations was examined in relation to their change in accuracy. Performance was tracked longitudinally over 11 time points, from the beginning of kindergarten (mean age = 5.7 years) to the end of second grade (n= 217). Accuracy in number combinations increased steadily during the time period while frequency of finger use declined. Correlations between finger use and accuracy decreased gradually, ranging from 0.60 in kindergarten to -0.15 at the end of second grade. Low-income children showed linear growth in frequency of finger use while middle-income children slowed down by second grade and even started to decline. Although girls and boys showed similar growth patterns in frequency and accuracy, boys used their fingers less often than girls and were more accurate. The findings indicate that finger use is most adaptive when children are first learning number combinations, but this benefit lessens over time.     

Langzeitwirkungen psychoanalytischer und verhaltenstherapeutischer Langzeitpsychotherapien

The prospective study compares 31 patients in long-term behavior therapy with 31 patients in psychoanalytically oriented long-term therapy. A naturalistic design was applied within the German health system. All patients underwent a diagnostic interview (SCID) by an external interviewer. Only patients who fulfilled the DSM III-R criteria for a depression or an anxiety disorder were included in the study. Although the diagnoses of the patients undergoing long-term behaviour therapy and long-term psychoanalytical psychotherapy were comparable, we found that they differed in various ways. The differences arose in a number of characteristics, such as education, access to psychotherapy (recommended by professionals versus patients introducing themselves), usage of psychotropic medication, and the strain of symptoms. The average duration of long-term behavior therapy was 2.4 years and 64 sessions. The average duration of psychoanalytically oriented long-term therapy was 3.6 years and 209 sessions. Symptoms (SCL-90-R) and interpersonal problems (IIP) were examined at the beginning, after 1 year, 2.5 years, 3.5 years and after 7 years. Both groups showed significant degrees of improvement within the first 3.5 years and remained stabilized in the following 3.5 years regarding the symptomatic aspects. Focussing on the interpersonal problems, group PA showed further improvement after the 3.5-year period. The BT group however, showed no further improvement after 3.5 years but stabilized. The evaluated phase-model of psychotherapeutic change for short-term therapy was confirmed more clearly for long-term therapies of psychoanalytical orientation than for long-term therapies of behavioral orientation.     

Internet access and use among homeless and indigent drug users in Long Beach, California.

There has been a growing interest in using the Internet to access a variety of populations for prevention education and health care. It is not clear that this is viable for homeless and other marginalized populations. The purpose of this study was to describe Internet access and use among a sample of homeless and indigent drug users. A brief questionnaire was developed to assess computer ownership, use, email, and Internet access and use. Participants were recruited through a community-based human immunodeficiency virus (HIV) prevention program. 265 participants completed the questionnaire. While 55% had ever used a computer in their lifetime, only 25% had ever owned a computer, 24% had ever had their own email account, 33% had access to a working computer in the last 30 days, 10% had sent or received email in the last 30 days, and 19% had surfed or accessed information on the Internet in the last 30 days. Logistic regression predicting lifetime use of a computer showed predictive factors of having completed high school (Odds Ratio [OR] = 4.5; 95% Confidence Interval [CI] = 2.41, 8.38) and number of days used amphetamines in the last 30 days, per 5 days of use (OR = 1.64; 95% CI = 1.18, 2.27). Inversely related were age, per 5 years of age (OR = 0.78; 95% CI = 0.65, 0.93) and number of days used marijuana in the last 30 days, per 5 days of use (OR = 0.97; 95% CI = 0.76, 0.99). Very low access and usage suggest that Internet-based public health education models be reexamined for this population. The association with amphetamine use may indicate a facilitating effect of amphetamine by heightening awareness and increasing wakefulness.     

Relief from Rescue

Philosophical Studies - Moral extremists argue for highly demanding duties of beneficence on the ground that accepting a more moderate position commits us to denying the common-sense moral...