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961.
962.
Previous studies have suggested that body size and locomotor performance are targets of Darwinian selection in reptiles. However, much of the variation in these traits may derive from phenotypically plastic responses to incubation temperature, rather than from underlying genetic variation. Intriguingly, incubation temperature may also influence cognitive traits such as learning ability. Therefore, we might expect correlations between a reptile’s size, locomotor speed and learning ability either due to selection on all of these traits or due to environmental effects during egg incubation. In the present study, we incubated lizard eggs (Scincidae: Bassiana duperreyi) under ‘hot’ and ‘cold’ thermal regimes and then assessed differences in hatchling body size, running speed and learning ability. We measured learning ability using a Y-maze and a food reward. We found high correlations between size, speed and learning ability, using two different metrics to quantify learning (time to solution, and directness of route), and showed that environmental effects (incubation temperature) cause these correlations. If widespread, such correlations challenge any simple interpretation of fitness advantages due to body size or speed within a population; for example, survivors may be larger and faster than nonsurvivors because of differences in learning ability, not because of their size or speed. 相似文献
963.
Sanni Somppi Heini Törnqvist Laura Hänninen Christina M. Krause Outi Vainio 《Animal cognition》2014,17(3):793-803
Faces play an important role in communication and identity recognition in social animals. Domestic dogs often respond to human facial cues, but their face processing is weakly understood. In this study, facial inversion effect (deficits in face processing when the image is turned upside down) and responses to personal familiarity were tested using eye movement tracking. A total of 23 pet dogs and eight kennel dogs were compared to establish the effects of life experiences on their scanning behavior. All dogs preferred conspecific faces and showed great interest in the eye area, suggesting that they perceived images representing faces. Dogs fixated at the upright faces as long as the inverted faces, but the eye area of upright faces gathered longer total duration and greater relative fixation duration than the eye area of inverted stimuli, regardless of the species (dog or human) shown in the image. Personally, familiar faces and eyes attracted more fixations than the strange ones, suggesting that dogs are likely to recognize conspecific and human faces in photographs. The results imply that face scanning in dogs is guided not only by the physical properties of images, but also by semantic factors. In conclusion, in a free-viewing task, dogs seem to target their fixations at naturally salient and familiar items. Facial images were generally more attractive for pet dogs than kennel dogs, but living environment did not affect conspecific preference or inversion and familiarity responses, suggesting that the basic mechanisms of face processing in dogs could be hardwired or might develop under limited exposure. 相似文献
964.
Róbert Urbán Réka Szigeti Gyöngyi Kökönyei Zsolt Demetrovics 《Behavior research methods》2014,46(2):488-498
The Rosenberg Self-Esteem Scale (RSES) is a widely used measure for assessing self-esteem, but its factor structure is debated. Our goals were to compare 10 alternative models for the RSES and to quantify and predict the method effects. This sample involves two waves (N =2,513 9th-grade and 2,370 10th-grade students) from five waves of a school-based longitudinal study. The RSES was administered in each wave. The global self-esteem factor with two latent method factors yielded the best fit to the data. The global factor explained a large amount of the common variance (61% and 46%); however, a relatively large proportion of the common variance was attributed to the negative method factor (34 % and 41%), and a small proportion of the common variance was explained by the positive method factor (5% and 13%). We conceptualized the method effect as a response style and found that being a girl and having a higher number of depressive symptoms were associated with both low self-esteem and negative response style, as measured by the negative method factor. Our study supported the one global self-esteem construct and quantified the method effects in adolescents. 相似文献
965.
Björn Lidestam 《Behavior research methods》2014,46(2):499-516
A method for creating and presenting video-recorded synchronized audiovisual stimuli at a high frame rate—which would be highly useful for psychophysical studies on, for example, just-noticeable differences and gating—is presented. Methods for accomplishing this include recording audio and video separately using an exact synchronization signal, editing the recordings and finding exact synchronization points, and presenting the synchronized audiovisual stimuli with a desired frame rate on a cathode ray tube display using MATLAB and Psychophysics Toolbox 3. The methods from an empirical gating study (Moradi, Lidestam, & Rönnberg, Frontiers in Psychology 4:359, 2013) are presented as an example of the implementation of playback at 120 fps. 相似文献
966.
We investigated attentional demands in visual rhythm perception of periodically moving stimuli using a visual search paradigm. A dynamic search display consisted of vertically “bouncing dots” with regular rhythms. The search target was defined by a unique visual rhythm (i.e., a shorter or longer period) among rhythmic distractors with identical periods. We found that search efficiency for a faster or a slower periodically moving target decreased as the number of distractors increased, although searching for a faster target was about one second faster than searching for a slower target. We conclude that perception of a visual rhythm defined by a unique period is not a “pop-out” process, but a serial one that demands considerable attention. 相似文献
967.
968.
Our aim was to identify the ethical issues faced by students in the behavioral and natural sciences during their doctoral programmes. The participants were 28 PhD students who were interviewed about their doctoral study and supervision experiences. We identified a total of 102 ethical issues compromising the principles of nonmaleficence, beneficence, autonomy, justice, or fidelity. There were some differences in emphases, with the students in the behavioral sciences displaying a broader range of ethical compromises than the students in the natural sciences. Ethical problems emerged in the individual supervisor–student relationships, but often problems involving the scholarly community appeared in the background. 相似文献
969.
970.
Alexandru Agache Birgit Leyendecker Esther Schäfermeier Axel Schölmerich 《European Journal of Developmental Psychology》2014,11(2):259-277
This study explored the role of fathers' involvement for life satisfaction changes among 598 cohabitating couples before and after childbirth using data from the German Socio-Economic Panel (GSOEP). We included longitudinal data and reports from both parents on their time spent on housework and childcare and their life satisfaction. Piecewise latent growth models showed that fathers' relative involvement trajectories for housework and childcare (amount of time men spent compared to their partners) were positively correlated. Fathers' relative involvement was perceived as supportive for mothers' childcare. In families where fathers were more involved, life satisfaction trajectories were much steeper; both parents had elevated levels around birth and returned to their baseline levels compared to families with less-involved fathers. Fathers who were less involved did not increase in life satisfaction at birth and decreased below their baseline levels within the third year post-birth. 相似文献