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.     

Biasing the development of response topography with nonspecific positive and negative evocative verbal stimuli

Conditioned response (CR) rate and development of CR latency, rise time, and airpuff attenuation were examined for V- and C-form responders using two nonspecific command words, do and don't, as conditioned stimuli (CSs) in single-cue, double-cue, and differential eyelid conditioning. In both single-cue and differential conditioning, regardless of the command word used to signal the unconditioned stimulus (UCS), the Vs produced a higher response rate and learned a better UCS-attenuating response topography than the Cs. However, in a double-cue conditioning paradigm in which both command words were presented alone on different trials and reinforced, response latency was longer and puff attenuation poorer among Vs than when the UCS was signaled by a unique cue. In contrast, adding a second reinforced cue actually enhanced the development of puff-avoidant CR topographies among Cs compared to single-cue conditioning. These results and others indicate that response topography development is to some extent a labile process that can be biased toward either good or poor puff-avoidant properties and that the factors responsible for influencing CR topography differ for Vs and Cs.     

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.     

Relations of psychological distress with objective individual,family, and neighborhood characteristics of urban adolescents

This paper describes the relations of psychological distress with 11 ecological factors (5 community, 4 family, and 2 individual) among 423 older urban adolescents who are predominantly people of color. Data were obtained by means of self-report via group-administered questionnaires given between 1994 and 1996; most scales are multi-item. There is wide variation in distress. There are very few statistically significant relationships between the ecological factors and distress, and those are negligible. Girls whose parents have less education and live in extended families have higher distress; family and individual domains are correlated .04 and .03 with distress and the community domain .00, so this ecological model accounts for a mere 7%, of the common total variance in distress.     

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.     

Test context affects recollection and familiarity ratings: implications for measuring recognition experiences

The binary remember/know task requires participants to dichotomize their subjective recognition experiences into those with recollection and those only with familiarity. Many variables have produced dissociative effects on remember/know judgments. In contrast, having participants make independent recollection/familiarity ratings has consistently produced parallel effects, suggesting the dissociations may be artifacts of using binary judgments. Bodner and Lindsay (2003) reported a test-list context effect with binary judgments: Increased remembering but decreased knowing for a set of critical items tested with a set of less-memorable (vs. more-memorable) items. Here we report a parallel effect of test-list context on recollection and familiarity ratings, induced by a shift in response bias. We argue that independent ratings are preferable to binary judgments because they allow participants to directly report the co-occurrence of recollection and familiarity for each item. Implications for the measurement of self-reported recognition experiences, and for accounts of recognition memory, are discussed.     

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.