Motion perception and aging.

The authors used a correlated motion paradigm to investigate the effects of aging and gender on motion sensitivity. In 2 experiments with a total of 50 elderly and 50 young subjects, motion thresholds were significantly higher for elderly women. The correlated motion signal, which was embedded in random motion, may have been coherent to subjects in much the same way a form is in Witkin's Embedded Figures Test (EFT). In Experiment 2, EFT scores were obtained. A significant positive relationship between motion thresholds and EFT performance was found within each age group. Although gender-related perceptual style differences may contribute to motion perception effects, the authors argue that a common neural factor contributes to performance on both the EFT and the correlated motion task.     

Introduction to two-dimensional Fourier analysis

The application of two-dimensional Fourier analysis provides new avenues for research in visual perception. This tutorial serves as an introduction to some of the methods used in two-dimensional Fourier analysis and an introduction to two-dimensional image processing in general.     

Perception of place-of-articulation information in natural speech by monkeys versus humans

Four monkeys and 6 humans representing five different native languages were compared in the ability to categorize natural CV tokens of /b/ versus /d/ produced by 4 talkers of American English (2 male, 2 female) in four vowel contexts (/i, e, a, u/). A two-choice "left/right" procedure was used in which both percentage correct and response time data were compared between species. Both measures indicated striking context effects for monkeys, in that they performed better for the back vowels /a/ and /u/ than for the front vowels /i/ and /e/. Humans showed no context effects for the percentage correct measure, but their response times showed an enhancement for the /i/ vowel, in contrast with monkeys. Results suggest that monkey perception of place of articulation is more dependent than human perception on the direction of the F2 onset transitions of syllables, since back-vowel F2s differentiate /b/ and /d/ more distinctively. Although monkeys do not provide an accurate model of the adult human in place perception, they may be able to model the preverbal human infant before it learns a more speech-specific strategy of place information extraction.     

Change in self-stigma among persons with schizophrenia enrolled in rehabilitation: associations with self-esteem and positive and emotional discomfort symptoms

Self-stigma is a barrier to the recovery of persons with schizophrenia. Little is known about whether participation in rehabilitation is naturalistically linked to declines in self-stigma, and if so, what is correlated with changes in self-stigma. The current study examined in a quasi-experimental design the rate of change of self-stigma and whether changes were correlated with self-esteem, positive symptoms, and emotional distress for persons enrolled in rehabilitation. Symptoms were measured using the Positive and Negative Syndrome Scale (Kay, Fizsbein, & Opler, 1987), self-esteem was measured with the Multidimensional Self-Esteem Inventory (Lysaker, Ringer, & Davis, 2008), and self-stigma was assessed using the Internalized Stigma of Mental Illness Scale (Ritsher, Otilingam, & Grajales, 2003). Seventy persons with schizophrenia who worked at least one month in a vocational rehabilitation program were assessed on all measures at baseline and five months later. Results indicated a 25% decrease in self-stigma for 38% of the sample; these individuals tended to have less emotional distress both at baseline and follow-up, and had higher levels of self-esteem at follow-up. No differences in positive symptoms were found for groups whose stigma did or did not decrease. Results suggest that decreases in self-stigma may be correlated with increased self-esteem, while higher levels of emotional distress may be a barrier to stigma reduction.     

Non-symbolic arithmetic abilities and mathematics achievement in the first year of formal schooling

We examine the nature of motor representations evoked during comprehension of written sentences describing hand actions. We distinguish between two kinds of hand actions: a functional action, applied when using the object for its intended purpose, and a volumetric action, applied when picking up or holding the object. In Experiment 1, initial activation of both action representations was followed by selection of the functional action, regardless of sentence context. Experiment 2 showed that when the sentence was followed by a picture of the object, clear context-specific effects on evoked action representations were obtained. Experiment 3 established that when a picture of an object was presented alone, the time course of both functional and volumetric actions was the same. These results provide evidence that representations of object-related hand actions are evoked as part of sentence processing. In addition, we discuss the conditions that elicit context-specific evocation of motor representations.     

Factors affecting processing mode in visual search

Visual search was studied under a variety of conditions to clarify some differences among the results of previous investigations and to provide a testing ground for models of visual information processing. Display configuration, target and field composition, exposure duration, and display size (up to 16 elements) were among the parameters investigated. In some conditions, mean reaction time was essentially invariant with display size, while in other conditions it increased substantially and linearly with display size. Current models of visual information processing were evaluated in the light of these and previous findings; all were found wanting. The data seem to demand a system subject to flexible cognitive control processes.     

Models for school psychology: Dimensions,barriers, and implications

This article argues that the development of school psychology may be seriously retarded unless a program is developed to overcome several hurdles. It is proposed that the several models of school psychology offer the potential but no guarantee that the profession will develop in an appropriate fashion.