Nonspatial attributes of stimuli can influence spatial limitations of attentional control

A wide variety of psychophysical and neurophysiological research suggests that when stimuli are very close together, they cannot be attended separately. As a consequence, they cannot be represented as individual items with specific feature information associated with them. Here we report evidence that the spatial control of attention can be modulated by nonspatial features of the stimuli (such as color and luminance). Observers shifted attention from item to item within highly dense arrays of stimuli. Performance was extremely poor when all of the items in the array were an identical gray. In contrast, performance improved when items differed in color. This finding indicates that nonspatial features, such as color, can facilitate spatial selection and suggests moreover that features can be reliably associated with particular items even when the items are densely clustered.     

An Examination of a Functional Mixed-Effects Modeling Approach to the Analysis of Longitudinal Data

Growth curve modeling is one of the main analytical approaches to study change over time. Growth curve models are commonly estimated in the linear and nonlinear mixed-effects modeling framework in which both the mean and person-specific curves are modeled parametrically with functions of time such as the linear, quadratic, and exponential. However, when more complex nonlinear trajectories need to be estimated and researchers do not have a priori knowledge of an appropriate functional form of growth, parametric models may be too restrictive. This paper reviews functional mixed-effects models, a nonparametric extension of mixed-effects models that permit both the mean and person-specific curves to be estimated without assuming a prespecified functional form of growth. Details of the model are presented along with results from a simulation study and an empirical example. The simulation study showed functional mixed-effects models performed reasonably well under various conditions commonly associated with longitudinal panel data, such as few time points per person, irregularly spaced time points across persons, missingness, and nonlinear trajectories. The usefulness of functional mixed-effects models is illustrated by analyzing empirical data from the Early Childhood Longitudinal Study – Kindergarten Class of 1998–1999.     

Sleep disruption explains age-related prospective memory deficits: implications for cognitive aging and intervention

The high prevalence of sleep disruption among older adults may have implications for cognitive aging, particularly for higher-order aspects of cognition. One domain where sleep disruption may contribute to age-related deficits is prospective memory—the ability to remember to perform deferred actions at the appropriate time in the future. Community-dwelling older adults (55–93 years, N = 133) undertook assessment of sleep using actigraphy and participated in a laboratory-based prospective memory task. After controlling for education, sleep disruption (longer awakenings) was associated with poorer prospective memory. Additionally, longer awakenings mediated the relationship between older age and poorer prospective memory. Other metrics of sleep disruption, including sleep efficiency and wake after sleep onset, were not related to prospective memory, suggesting that examining the features of individual wake episodes rather than total wake time may help clarify relationships between sleep and cognition. The mediating role of awakening length was partially a function of greater depression and poorer executive function (shifting) but not retrospective memory. This study is among the first to examine the association between objectively measured sleep and prospective memory in older adults. Furthermore, this study is novel in suggesting sleep disruption might contribute to age-related prospective memory deficits; perhaps, with implications for cognitive aging more broadly. Our results suggest that there may be opportunities to prevent prospective memory decline by treating sleep problems.     

A Theory of Truthmaker Content I: Conjunction,Disjunction and Negation

I develop a basic theory of content within the framework of truthmaker semantics and, in the second part, consider some of the applications to subject matter, common content, logical subtraction and ground.     

Problem-solving training via videoconferencing for family caregivers of persons with spinal cord injuries: a randomized controlled trial

Objective

To examine the effectiveness of an individualized problem-solving intervention delivered in videoconferencing sessions with family caregivers of persons living with a spinal cord injury (SCI) and possible contagion effects on care recipients.

Design

Family caregivers were randomly assigned to an education-only control group or an intervention group in which participants received problem-solving training (PST) in monthly videoconference session for a year.

Participants

Sixty-one caregivers (54 women, 7 men) and their care recipients (40 men, 21 women) consented to participate.

Main outcome measures

The Social Problem-Solving Inventory-Revised was administered to caregivers. Caregivers and care recipients completed the Inventory to Diagnose Depression, the SF-36 and the Satisfaction with Life scale at pre-treatment, 6 months and 12 months.

Results

Twenty-eight caregivers discontinued the study and their follow-up data were unavailable at the final assessment. Older caregivers were more likely than younger caregivers to remain in the study. Intent-to-treat analyses projected a significant decrease in depression among caregivers receiving PST; efficacy analyses indicated this effect was pronounced at the 6th month assessment. ITT analyses and efficacy analyses revealed that care recipients of caregivers receiving PST reported gains in social functioning over time.

Conclusions

Community-based, telehealth interventions may benefit family caregivers and their care recipients, but the mechanisms of these effects are unclear. Attrition and sample issues should be considered in future studies with these populations.     

Identity criteria and ground

I propose formulating identity criteria as generic statements of ground, thereby avoiding objections that have been made to the more usual formulations.     

Ego atrophy in addiction illustrated through American cultural music folklore

Popular music is an artifact of folklore that can provide a keen insight into societal complexity. As a window with minimal censorship, it allows access to a subgroup whose motifs are often obfuscated from within and without by defensive and self righteous distortions. Music is a primary source depicting the strivings and failings of a culture or its tributaries. An overview is offered of the American social historical context of substance abuse, as it informs the theory of ego atrophy to conceptualize addiction. In this study, it is appealed to as an aid in the elaboration of addictive behavior. Adjunctively, major themes in movie pictures are referenced as parallel, albeit less refined, indices of stereotype in the culture. Together with societal laws and mores, these markers point to a specific behavioral and value system that typifies the ego of the substance abuser.