Species difference in the timing of gaze movement between chimpanzees and humans

How do humans and their closest relatives, chimpanzees, differ in their fundamental abilities for seeing the visual world? In this study, we directly compared the gaze movements of humans and the closest species, chimpanzees, using an eye-tracking system. During free viewing of a naturalistic scene, chimpanzees made more fixations per second (up to four) than did humans (up to three). This species difference was independent of the semantic variability of the presented scenes. The gap–overlap paradigm revealed that, rather than resulting from the sensitivity to the peripherally presented stimuli per se, the species difference reflected the particular strategy each species employed to solve the rivalry between central (fixated) and peripheral stimuli in their visual fields. Finally, when presented with a movie in which small images successively appeared/disappeared at random positions at the chosen presentation rate, chimpanzees tracked those images at the point of fixation for a longer time than did humans, outperforming humans in their speed of scanning. Our results suggest that chimpanzees and humans differ quantitatively in their visual strategies involving the timing of gaze movement. We discuss the functional reasons for each species’ employing such specific strategies.     

Should We Treat Depression with drugs or psychological interventions? A Reply to Ioannidis

We reply to the Ioannidis's paper "Effectiveness of antidepressants; an evidence based myth constructed from a thousand controlled trials." We disagree that antidepressants have no greater efficacy than placebo. We present the efficacy from hundreds of trials in terms of the percentage of patients with a substantial clinical response (a 50% improvement or more symptomatic reduction). This meta-analysis finds that 42-70% of depressed patients improve with drug and 21%-39% improve with placebo. The response benefit of antidepressant treatment is 33%-11% greater than placebo. Ioannidis argues that it would be vanishingly smaller because systematic biasing in these clinical trials would reduce the drug-placebo difference to zero. Ioannidis' argument that antidepressants have no benefit is eroded by his failures of logic because he does not present any evidence that there are a large number of studies where placebo is substantially more effective than drug. (To reduce to zero, one would also have to show that some of the unpublished studies find placebo better than drug and have substantial systematic or methodological bias). We also present the empirical evidence showing that these methodological concerns generally have the opposite effect of what Ioannidis argues, supporting our contention that the measured efficacy of antidepressants likely underestimates true efficacy. Our most important criticism is Ioannidis’ basic underlying argument about antidepressants that if the existing evidence is imperfect and methods can be criticized, then this proves that antidepressant are not efficacious. He presents no credible evidence that antidepressants have zero effect size. Valid arguments can point out difficulties with the data but do not prove that a given drug had no efficacy. Indeed better evidence might prove it was more efficacious that originally found. We find no empirical or ethical reason why psychiatrists should not try to help depressed patients with drugs and/or with psychotherapeutic/behavioral treatments given evidence of efficacy even though our treatment knowledge has limitations. The immense suffering of patients with major depression leads to ethical, moral, professional and legal obligations to treat patients with the best available tools at our disposal, while diligently and actively monitoring for adverse effects and actively revising treatment components as necessary.     

Observation and physical practice: coding of simple motor sequences

An experiment was conducted to determine the coordinate system used in the development of movement codes during observation and utilized on later physical practice performance of a simple spatial-temporal movement sequence. The task was to reproduce a 1.3-s spatial-temporal pattern of elbow flexions and extensions. An intermanual transfer paradigm with a retention test and two transfer tests was used: a mirror transfer test where the same pattern of muscle activation and limb joint angles was required and a nonmirror transfer test where the visual-spatial pattern of the sequence was reinstated on the transfer test. The results indicated a strong advantage for participants in the physical practice condition when transferred to the mirror condition in which the motor coordinates (e.g., pattern of muscle activation and joint angles) were reinstated relative to transfer performance when the visual-spatial coordinates were reinstated (visual and spatial location of the target waveform). The observation group, however, demonstrated an advantage when the visual-spatial coordinates were reinstated. These results demonstrate that codes based in motor coordinates can be developed relatively quickly for simple rapid movement sequences when participants are provided physical practice, but observational practice limits the system to the development of codes based in visual-spatial coordinates. Performances of control participants, who were not permitted to practise or observe the task, were quite poor on all tests.     

Trust in Nanotechnology? On Trust as Analytical Tool in Social Research on Emerging Technologies

Trust has become an important aspect of evaluating the relationship between lay public and technology implementation. Experiences have shown that a focus on trust provides a richer understanding of reasons for backlashes of technology in society than a mere focus of public understanding of risks and science communication. Therefore, trust is also widely used as a key concept for understanding and predicting trust or distrust in emerging technologies. But whereas trust broadens the scope for understanding established technologies with well-defined questions and controversies, it easily fails to do so with emerging technologies, where there are no shared questions, a lack of public familiarity with the technology in question, and a restricted understanding amongst social researchers as to where distrust is likely to arise and how and under which form the technology will actually be implemented. Rather contrary, ‘trust’ might sometimes even direct social research into fixed structures that makes it even more difficult for social research to provide socially robust knowledge. This article therefore suggests that if trust is to maintain its important role in evaluating emerging technologies, the approach has to be widened and initially focus not on people’s motivations for trust, but rather the object of trust it self, as to predicting how and where distrust might appear, how the object is established as an object of trust, and how it is established in relation with the public.     

?Psychische St?rung�� als Begr��ndung f��r staatliche Eingriffe in Grundrechte des Individuums

When dealing with ?old cases?? of preventive detention as well as retrospectively ordered preventive detention, a continuation of confinement should be possible if the offender involved suffers from a ??mental disorder?? which constitutes the danger of future serious violent or sexual crimes. In this psychiatric article it will be explained that the terms ??mental illness?? and also ??mental disorder?? must retain an empirical scientifically definable psychiatric content in order not to instigate deception. They must also be functionally defined in each judicial environment (police law, social law, civil law and criminal law) with respect to the capabilities of the individual which are impaired by the mental disorder. Such an approach could prevent a misuse of psychiatry for purely political security purposes.     

Coronary Intervention Improves Disease Specific Health-Related Quality of Life but Not Individualised Quality of Life: A Potential Response Shift Effect?

To explore potential response shift effects with different quality of life (QoL) instruments in cardiac patients undergoing coronary intervention. Study Design and Setting: Recalibration was assessed with the disease specific health-related quality of life (HRQL) instrument MacNew in combination with a then-test approach. Reconceptualisation and reprioritisation were assessed with the individualised QoL instrument SEIQoL-DW. Significant treatment effects were seen on the MacNew (global Δ: 0.6 ± 1.1, p = 0.004) but not on the SEIQoL-DW (Δ: 3.3 ± 16, p = 0.37) 6 months after coronary intervention. No recalibration effect was found on the MacNew then-test, while with the SEIQOL-DW potential response shift effects of reconceptualisation and reprioritisation were seen. For the first time response shift effects were explored in cardiac patients undergoing coronary intervention. This study confirmed that there is a clinically significant improvement in disease specific HRQL over time following successful coronary interventions. However, no treatment effect was seen for individualised QoL with the SEIQoL-DW. This might be due to reconceptualisation and reprioritisation response effects. Future studies need to focus on exploring response shift effects, and the interrelationship between its different components, captured by different patient reported outcome instruments in larger patient groups undergoing coronary interventions.     

Kontroverse zu Beschwerdenvalidierungsverfahren bei der Begutachtung psychischer St?rungen

The value of symptom validity tests in a forensic context is currently the subject of a controversial debate in Germany. The discussion primarily focuses on neuropsychological symptom validity tests, however, tests specific for mental disorders are neglected. Unfortunately, no assessment tools for symptom validation of mental disorders of German origin are available and adaptations of available English state of the art instruments have not yet been tested. Further research of assessment development and qualitative analysis of the decision-making process in medicolegal evaluation is needed in German speaking countries.