Auditory contralateral induction: An early stage in binaural processing

Binaural interaction was studied using headphones presenting signals (tones or filtered speech) to one ear and noises of various spectral compositions to the other. Every half-second, the sides receiving the signal and noise were reversed. The noise was always perceived to alternate from side to side, but the signal appeared to be stationary and diffusely localized about the midsaggital plane when the noise contained the spectral components of the signal at appropriate intensity levels. This delateralization of a monaural signal results from a process called “contralateral induction” (CI). Additional observations indicate that CI corresponds to an early stage in binaural interaction which generally escapes notice because of further perceptual processing.     

Parent and actometer measures of motor activity level in the young infant

Motor activity level is one dimension of infant temperament for which parental judgment can be validated against a truly independent criterion. Two studies were conducted, the first involving a 27-min sample of behavior in a structured, attention-getting situation, and the second involving a 24-hr sample of in-home behavior. In both studies, parent perception of the 3- or 4-month-old as measured by the Activity Level (AL) scale of the Rothbart Infant Behavior Questionnaire was compared to the composited readings from four mechanical motion recorders (actometers) worn, one per limb, by the infant. The AL scale did not correlate with the actometer measure, r=.05 and R=.00, and the expected convergence of the 3-month version of the IBQ activity scale with its mechanical counterpart was not found. In the 24-hr study, birth order and ponderal index were significantly correlated with 24-hr actometer scores; first-borns and thin infants were most active.     

Behavioral anatomy of a hunt

It is commonly thought that the mind constructs predictive models of the environment to plan an appropriate behavioral response. Therefore a more predictable environment should entail better performance, and prey should move in an unpredictable (random) manner to evade capture, known as protean motion. To test this, we created a novel experimental design and analysis in which human participants took the role of predator or prey. The predator was set the task of capturing the prey, while the prey was set the task of escaping. Participants performed this task standing on separate sides of a board and controlling a marker representing them. In three conditions, the prey followed a pattern of movement with varying predictability (predictable, semi-random, and random) and in one condition moved autonomously (user generated). The user-generated condition illustrated a naturalistic, dynamic environment involving a purposeful agent whose degree of predictability was not known in advance. The average distance between participants was measured through a video analysis custom-built in MATLAB. The user-generated condition had the largest average distance. This indicated that, rather than moving randomly (protean motion), humans may naturally employ a cybernetic escape strategy that dynamically maximizes perceived distance, regardless of the predictability of this strategy.

     

Exploring Wellbeing in Youth with Vision Impairment: Insights for Vision Rehabilitation

Applied Research in Quality of Life - This article explores the discussions of 21 young Australians (aged 12–25) with vision impairment regarding their lived experiences and what it meant for...     

Naturalistic evaluation of suicidal ideation: variability and relation to attempt status

Suicidal ideation has been thought to have a relatively stable course across weeks and months. However, daily changes in levels of ideation have not been adequately examined despite the importance of potential variability clinically and conceptually. For example, it has been suggested that variability in suicidal ideation may become less closely tied to variability in other mood symptoms (e.g., depression, hopelessness) among individuals with multiple suicide attempts. The present report had two related goals: (1) to prospectively evaluate suicidal ideation and related mood symptoms, and (2) to determine whether suicide attempt status predicted a decreased association between ideation and other mood symptoms. Non-clinical participants (N=108) with varying levels of suicidal ideation and number of previous suicide attempts completed the beck hopelessness scale (BHS), beck depression inventory (BDI), and suicide probability scale (SPS) every day for 4 weeks. Findings suggested considerable variability in suicidal ideation, especially for multiple attempters. Multiple attempt status predicted a decreased association between suicidal ideation and depression, although the results were only marginally significant. These findings have implications for conceptual models of suicide risk as well as assessment and treatment of suicidal individuals.