Interpreting the effects of image manipulation on picture perception in pigeons (Columba livia) and humans (Homo sapiens)

The effects of picture manipulations on humans' and pigeons' performance were examined in a go/no-go discrimination of two perceptually similar categories, cat and dog faces. Four types of manipulation were used to modify the images. Mosaicization and scrambling were used to produce degraded versions of the training stimuli, while morphing and cell exchange were used to manipulate the relative contribution of positive and negative training stimuli to test stimuli. Mosaicization mainly removes information at high spatial frequencies, whereas scrambling removes information at low spatial frequencies to a greater degree. Morphing leads to complex transformations of the stimuli that are not concentrated at any particular spatial frequency band. Cell exchange preserves high spatial frequency details, but sometimes moves them into the "wrong" stimulus. The four manipulations also introduce high-frequency noise to differing degrees. Responses to test stimuli indicated that high and low spatial frequency information were both sufficient but not necessary to maintain discrimination performance in both species, but there were also species differences in relative sensitivity to higher and lower spatial frequency information.     

The influence of heightened body‐awareness on walking through apertures

The reported study measured the ratio between aperture‐width and hip‐width that marked the critical transition from frontal walking to body rotation for male and female participants. Half of the participants of each sex wore form‐fitting lycra clothes and half loose‐fitting jogging suits. Participants wearing the form‐fitting clothing reported heightened body awareness relative to those wearing the loose‐fitting clothing. For male participants this difference was reflected in a smaller aperture‐to‐hip ratio in the form‐fitting than loose‐fitting clothing condition. That is, males walked frontally through smaller apertures when wearing form‐fitting than when wearing loose‐fitting clothing. For females there was no difference in walking action as a function of clothing style. Results are discussed in terms of the perception of action opportunities in the environment, the influence of body awareness on such perception and sex differences. Copyright © 2009 John Wiley & Sons, Ltd.     

Self-informant Agreement for Personality and Evaluative Person Descriptors: Comparing Methods for Creating Informant Measures

Little attention typically is paid to the way self-report measures are translated for use in self-informant agreement studies. We studied two possible methods for creating informant measures: (a) the traditional method in which self-report items were translated from the first- to the third-person and (b) an alternative meta-perceptual method in which informants were directed to rate their perception of the targets' self-perception. We hypothesized that the latter method would yield stronger self-informant agreement for evaluative personality dimensions measured by indirect item markers. We studied these methods in a sample of 303 undergraduate friendship dyads. Results revealed mean-level differences between methods, similar self-informant agreement across methods, stronger agreement for Big Five dimensions than for evaluative dimensions, and incremental validity for meta-perceptual informant rating methods. Limited power reduced the interpretability of several sparse acquaintanceship effects. We conclude that traditional informant methods are appropriate for most personality traits, but meta-perceptual methods may be more appropriate when personality questionnaire items reflect indirect indicators of the trait being measured, which is particularly likely for evaluative traits.     

Differing effects of systemically administered rapamycin on consolidation and reconsolidation of context vs. cued fear memories

Rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR) kinase, has attracted interest as a possible prophylactic for post-traumatic stress disorder (PTSD)-associated fear memories. We report here that although rapamycin (40 mg/kg, i.p.) disrupted the consolidation and reconsolidation of fear-potentiated startle paradigm to a shock-paired context, it did not disrupt startle increases to a 4-sec odor cue, even though post-training increases in amygdala mTOR activity were prevented by rapamycin (also 40 mg/kg, i.p.). Thus, while rapamycin may prove useful in retarding the development of some PTSD-associated memories, its relative ineffectiveness against cued fear memories may limit its clinical usefulness.     

Affording cooperation: Embodied constraints,dynamics, and action-scaled invariance in joint lifting

Understanding the physical and interpersonal constraints that afford cooperation during real-world tasks requires consideration of the fit between the environment and task-relevant dimensions of coactors and the coactors’ fit with each other. In the present study, we examined how cooperation can emerge during ongoing interaction using the simple task of two actors’ moving long wooden planks. The system dynamics showed hysteresis: A past-action mode persisted when both solo and joint actions were possible. Moreover, pairs whose arm spans were both short, both long, or mismatched made action-mode transitions at similar points, when scaled by a relational measure. The relational measure of plank length to arm span was dictated by the pair member with the shorter arm span, who, thus, had a greater need to cooperate during the task. The results suggest that understanding affordances for cooperation requires giving more consideration to constraints imposed by the fit between coactors’ action capabilities.     

Effects of context on eye movements when reading about possible and impossible events

Plausibility violations resulting in impossible scenarios lead to earlier and longer lasting eye movement disruption than violations resulting in highly unlikely scenarios (K. Rayner, T. Warren, B. J. Juhasz, & S. P. Liversedge, 2004; T. Warren & K. McConnell, 2007). This could reflect either differences in the timing of availability of different kinds of information (e.g., selectional restrictions, world knowledge, and context) or differences in their relative power to guide semantic interpretation. The authors investigated eye movements to possible and impossible events in real-world and fantasy contexts to determine when contextual information influences detection of impossibility cued by a semantic mismatch between a verb and an argument. Gaze durations on a target word were longer to impossible events independent of context. However, a measure of the time elapsed from first fixating the target word to moving past it showed disruption only in the real-world context. These results suggest that contextual information did not eliminate initial disruption but moderated it quickly thereafter.     

Social Psychology and Media: Critical Considerations

In this paper, we argue that media saturate everyday living, and that people engage with and are engaged by media in diverse and complex ways. We suggest a need for an informed social psychology of media that conceptualises media as social practice, and attends to media practices as they occur. We propose that much media psychology research is limited because it: (i) focuses too strongly on documenting causal, and usually negative, media effects; (ii) continues to apply unsuitable research methodologies and theories to investigating media and ignores advances in media research and theory arising outside the discipline; and (iii) largely ignores the social contexts in which media engagements occur. These arguments are illustrated by studies that take a more social and critical approach to media research and that show possibilities for overcoming these limitations and developing insights into psychological concerns enmeshed in media practices.     

Psychological Emptiness in the Zhuāngzǐ

Three views of psychological emptiness, or xū, can be found in the Zhuāngz?. The instrumental view values xū primarily as a means of efficacious action. The moderate view assigns it intrinsic value as an element of one Zhuangist vision of the good life. The radical view also takes it to be an element of the ideal life, but in this case the form of life advocated is that of the Daoist sage, who transcends mundane human concerns to merge with nature or the Dào. The instrumental and moderate views articulate a relatively commonsensical position, on which the agent continues to pursue at least some characteristically human projects. On the radical view, by contrast, the agent ceases to exercise agency and lives a life hardly recognizable as human. The three views thus signal a tension in Zhuangist ethics, and the unattractiveness of the radical view poses a potential obstacle to the application of Daoist ideas in contemporary ethical discourse. The paper argues that there are principled grounds within Zhuangist thought for detaching the instrumental and moderate views from the radical view and rejecting the latter.     

Elevated content of cortisol in hair of patients with severe chronic pain: a novel biomarker for stress

Hair analysis has been used to reflect long-term systemic exposure to exogenous drugs and toxins. Several studies have demonstrated the feasibility of measuring endogenous steroid hormones, e.g. cortisol, in hair. Recently, a study in macaques showed a significant increase in hair cortisol levels induced by stress. We explored whether hair cortisol levels may be used as a biomarker for long-term stress in humans. Patients with severe chronic pain, aged 18 years or older, receiving opioid treatment for at least one year were recruited. Controls were non-obese (body mass index, BMI < 30 mg/kg(2)) adults. The Perceived Stress Scale (PSS) questionnaire was used to assess perceived stress over the last 4 weeks. A hair sample was obtained from the vertex posterior. Cortisol was measured using an enzyme-linked immunosorbent assay. We included fifteen patients (nine females and six males) and 39 non-obese control subjects (20 females, 19 males). PSS scores (median and range) were significantly higher in chronic pain patients (24: 12-28) than in controls (12: 3-31)(P < 0.001). Hair cortisol contents (median and range) were significantly greater in chronic pain patients (83.1: 33.0-205 g/mg) than in controls (46.1: 27.2-200 pg/mg) (P < 0.01). We conclude that hair cortisol contents are increased in patients with major chronic stress. Measurement of cortisol levels in hair constitutes a novel biomarker of prolonged stress.