Distortions of perceived length in the frontoparallel plane: tests of perspective theories

The perceived length of a line segment in a frontoparallel plane is sometimes affected by the presence of other line segments in the visual field. Perspective theories attribute such interactions to size-constancy scaling: The configuration of line segments present in the visual field includes depth cues that trigger size scaling of each line segment. In three experiments, we test this claim for a range of simple configurations composed of two line segments joined at a point. These configurations include the inverted T configuration of the bisection illusion, as well as the L configuration of the horizontal-vertical illusion. We conclude that the available depth cues, even when supplemented by known biases in perspective interpretations, do not account for observed distortions in judgments of relative length.     

Stereoillusory motion concomitant with lateral head movements

Stationary objects in a stereogram can appear to move when viewed with lateral head movements. This illusory motion can be explained by the motion-distance invariance hypothesis, which states that illusory motion covaries with perceived depth in accordance with the geometric relationship between the position of the stereo stimuli and the head. We examined two predictions based on the hypothesis. In Experiment 1, illusory motion was studied while varying the magnitude of binocular disparity and the magnitude of lateral head movement, holding viewing distance constant. In Experiment 2, illusory motion was studied while varying binocular disparity and viewing distance, holding magnitude of head movement constant. Ancillary measures of perceived depth, perceived viewing distance, and perceived magnitude of lateral head movement were also obtained. The results from the two experiments show that the extent of illusory motion varies as a function of perceived depth, supporting the motion-distance invariance hypothesis. The results also show that the extent of illusory motion is close to that predicted from the geometry in crossed disparity conditions, whereas it is greater than the predicted motion in uncrossed disparity conditions. Furthermore, predictions based on perceptual variables were no more accurate than predictions based on geometry.     

Interference between verbal concept formation and spatial mental rotation in female subjects

In this study the relation between spatial cognition and verbal intelligence abilities was examined in case of 52 women. Interference between mental rotation performance and verbal intelligence scores was found. Women with good verbal abilities have lower scores in mental rotation tasks than subjects with poorer verbal abilities. This finding is in accordance with some basic models of a dual-coding system. The spatial functions represented in mental rotation interfered with verbal-based concept formation and lexical knowledge in college women.     

Location of the egocenter in kinesthetic space

The location of the egocenter in kinesthetic space was investigated in 4 experiments. Participants, with their eyes closed, adjusted a comparison stimulus after or while touching a standard in a transverse plane at the belly or shoulder level so that they perceived the line joining the comparison and the fixed standard as pointing directly at themselves. The mean location of the intersections of the obtained lines was taken as the location of the egocenter. The main results showed that the location of the kinesthetic egocenter depended on the hand or hands used for touching, the timing of touching, and the distance of the standard from the participant. Implications of these results were discussed in relation to models of the kinesthetic egocenter.     

Nanoindentation-induced elastic–plastic transition and size effect in α-Al2O3(0001)

The mechanical properties of α-Al₂O₃(0001) have been investigated using the technique of nanoindentation with a Berkovich indenter. Coupled with the Hertzian contact theory, a theoretical shear strength of 28?±?2?GPa was determined from the onset of pop-in events on load–displacement curves during loading, and the intrinsic hardness 30?±?3?GPa was obtained by analysis of the so-called indentation size effect, based on the concept of geometrically necessary dislocations. The predicted values of the shear strength, hardness and elastic modulus are in good agreement with available experimental data. The importance of experimentally calibrating the area function over the contact depth range prior to nanoindentation tests is emphasized.     

Hume's Experimental Method

In this article I attempt to reconstruct David Hume's use of the label ‘experimental’ to characterise his method in the Treatise. Although its meaning may strike the present-day reader as unusual, such a reconstruction is possible from the background of eighteenth-century practices and concepts of natural inquiry. As I argue, Hume's inquiries into human nature are experimental not primarily because of the way the empirical data he uses are produced, but because of the way those data are theoretically processed. He seems to follow a method of analysis and synthesis quite similar to the one advertised in Newton's Opticks, which profoundly influenced eighteenth-century natural and moral philosophy. This method brings him much closer to the methods of qualitative, chemical investigations than to mechanical approaches to both nature and human nature.     

A potential inflating effect in estimation models: Cautionary evidence from comparing performance enhancing drug and herbal hormonal supplement use estimates

ObjectivesThis paper compares two indirect prevalence estimation methods that offer protection beyond anonymity and are suitable for self-administration, for investigating the epidemiology of transgressive or socially sensitive behaviours.DesignIn this self-report study, 513 participants (58.7% male) from sports clubs across the UK and southern Ireland were asked to complete an anonymous survey containing the recently developed Single Sample Count (SSC), along with a comparative method Unrelated Question Model (UQM), using prohibited performance-enhancing drugs/substances (PED) as sensitive and hormone-boosting herbal supplements (HS) as non-sensitive control questions.MethodThe survey comprised of sections of SSC, UQM, social projection and simple network scale up methods. Respondents were asked to indicate whether they preferred the SSC or UQM for more protection and ease of completion.ResultsA large discrepancy was observed in prevalence estimates for PED using the UQM (58.4%) and SSC (19.8%), but not for HS (54.9% and 54.0%, respectively). The SSC prevalence estimate for PED was in keeping with the results from social projection (13.8% in own sport; 26.1% in all sports) and network scale up (19.3% for known and suspected doping combined). A clear preference was logged for SSC.ConclusionSSC, but not UQM, showed good concurrent validity with social projection and personal networks for PED; and good discriminant validity with HS. The observed discrepancy could be explained by strategic responding which can inflate the proportion of ‘yes’ answers in the UQM. Adaptation of the UQM for self-administration may lead to an unwanted upward response distortion via strategic responding.     

A Role for Cognitive Rehabilitation in Increasing the Effectiveness of Treatment for Alcohol Use Disorders

Neurocognitive impairments are prevalent in persons seeking treatment for alcohol use disorders (AUDs). These impairments and their physical, social, psychological and occupational consequences vary in severity across persons, much like those resulting from traumatic brain injury; however, due to their slower course of onset, alcohol-related cognitive impairments are often overlooked both within and outside of the treatment setting. Evidence suggests that cognitive impairments can impede treatment goals through their effects on treatment processes. Although some recovery of alcohol-related cognitive impairments often occurs after cessation of drinking (time-dependent recovery), the rate and extent of recovery is variable across cognitive domains and individuals. Following a long hiatus in scientific interest, a new generation of research aims to facilitate treatment process and improve AUD treatment outcomes by directly promoting cognitive recovery (experience-dependent recovery). This review updates knowledge about the nature and course of cognitive and brain impairments associated with AUD, including cognitive effects of adolescent AUD. We summarize current evidence for indirect and moderating relationships of cognitive impairment to treatment outcome, and discuss how advances in conceptual frameworks of brain-behavior relationships are fueling the development of novel AUD interventions that include techniques for cognitive remediation. Emerging evidence suggests that such interventions can be effective in promoting cognitive recovery in persons with AUD and other substance use disorders, and potentially increasing the efficacy of AUD treatments. Finally, translational approaches based on cognitive science, neurophysiology, and neuroscience research are considered as promising future directions for effective treatment development that includes cognitive rehabilitation.     

I don't believe but I pray: spirituality,instrumentality, or paranormal belief?

These three studies are among the first to systematically compare five Chinese religious groups on intrinsic (spiritual) and extrinsic (instrumental and paranormal) orientation. In Study 1, a Chinese version of the Index of Core Spiritual Experiences was developed. In Studies 2 and 3, spirituality and religious involvement was found to be greatest among Christians, followed in order by Buddhists, Taoists, traditional nones, and other nones. An instrumental purpose for religious activities and paranormal belief was found to be highest among Taoists, followed in order by Buddhists, traditional nones, other nones, and Christians. The results are consistent with the conclusion that Christianity offers the least support for an extrinsic religious orientation and the most support for an intrinsic religious orientation.