Die Bedeutung von “Figur” und “Grund” für bie unveränderter Schwarzinduktion bestimmte Helligkeitsschwellen

Ohne Zusammenfassung     

Perceptual invariance and the psychophysical law

The psychophysical power law, demonstrated empirically by Stevens, is derivable from two postulates concerning (1) the tendency of perceptual organizations to model the environment and (2) the tendency for perceptual relations to remain constant. The two postulates appear to rule out logarithmic laws of the Fechner type. The theory is extendable to multidimensional perceptions such as those encountered in speech and color vision. The power transformations produced by the sense organs may be of such form that they produce a perceptual space in which subsequent transformations need be only linear.     

Are you sure you forgot? Feeling of knowing in directed forgetting.

One significant issue in metamemory is how variables increasing memorability affect metamemory. Previous research has produced inconsistent results. The effect of directed forgetting on the magnitude and accuracy of feeling-of-knowing (FOK) judgments was investigated. Participants were presented with word pairs, some to be remembered and some to be forgotten, and then were asked to recall all target words regardless of initial instructions. For unrecalled items, they were asked to give FOK judgments about performance in a future memory task: a cued stem-completion task (Experiment 1) or a recognition test (Experiment 2). This encoding manipulation increased both the memory performance and the magnitude of FOK judgments. However, no such effect on the accuracy of FOK judgments was observed.     

Parallel working memory for spatial location and food-related object cues in foraging pigeons: binocular and lateralized monocular performance

During foraging, animals can increase their success by both remembering feeding sites and remembering food-related object cues. Because earlier studies have tested either the site or object memory in isolation, the aim of the present study was to evaluate how efficiently birds can utilize both memories simultaneously. Furthermore, the idea was tested that lateralization might be the principle of brain organization that allows for efficient parallel processing. Pigeons learned to search for food in a complex maze with 16 baited sites. To obtain the maximum reward they had to perform two tasks in parallel, a spatial working memory task and an object-specific working memory task. Birds performed well on this dual task but, compared with spatial working memory alone, they were impaired during the first choices of a trial (Experiment 1). When the left and the right brain hemispheres were tested separately by means of monocular occlusion (Experiment 2), object discrimination was better when birds used their right eye/left hemisphere. This was most pronounced during the first choices of a trial. On the spatial component of the task, performance on binocular trials was better than on monocular trials, but monocularly both hemispheres performed at the same level. Results show that on this dual task, discrimination of food-related object cues predominantly involved the left brain hemisphere whereas both hemispheres contributed equally to spatial performance.     

Examination of adolescents' negative thoughts, depressive mood, and family environment.

The focus of this study was the relationship among adolescents' negative thoughts, depressive mood, and family environment. Three hundred eleven students (aged 16 and 17 years) in public and private schools served as subjects. They were administered the Family Environment Scale, the Automatic Thoughts Questionnaire, and the Beck Depression Inventory. Family cohesion was found to be related to the degree of negative thoughts and depressive mood of the adolescents, but perceived control within the family was not.     

The importance of context information for the spatial specificity of gaze cueing

In three experiments, we investigated the spatial allocation of attention in response to central gaze cues. In particular, we examined whether the allocation of attentional resources is influenced by context information—that is, the presence or absence of reference objects (i.e., placeholders) in the periphery. On each trial, gaze cues were followed by a target stimulus to which participants had to respond by keypress or by performing a target-directed saccade. Targets were presented either in an empty visual field (Exps. 1 and 2) or in previewed location placeholders (Exp. 3) and appeared at one of either 18 (Exp. 1) or six (Exps. 2 and 3) possible positions. The spatial distribution of attention was determined by comparing response times as a function of the distance between the cued and target positions. Gaze cueing was not specific to the exact cued position, but instead generalized equally to all positions in the cued hemifield, when no context information was provided. However, gaze direction induced a facilitation effect specific to the exact gazed-at position when reference objects were presented. We concluded that the presence of possible objects in the periphery to which gaze cues could refer is a prerequisite for attention shifts being specific to the gazed-at position.