A Comparison of Two-Stage Approaches for Fitting Nonlinear Ordinary Differential Equation Models with Mixed Effects

Several approaches exist for estimating the derivatives of observed data for model exploration purposes, including functional data analysis (FDA; Ramsay &; Silverman, 2005 Ramsay, J. O., &; Silverman, B. W. (2005). Functional data analysis (2nd ed.). New York, NY: Springer-Verlag. [Google Scholar]), generalized local linear approximation (GLLA; Boker, Deboeck, Edler, &; Peel, 2010 Boker, S. M., Deboeck, P. R., Edler, C., &; Peel, P. K. (2010). Generalized local linear approximation of derivatives from time series. In S. Chow, E. Ferrer, &; F. Hsieh (Eds.), Statistical methods for modeling human dynamics: An interdisciplinary dialogue (pp. 161–178). New York, NY: Taylor &; Francis. [Google Scholar]), and generalized orthogonal local derivative approximation (GOLD; Deboeck, 2010 Deboeck, P. R. (2010). Estimating dynamical systms: Derivative estimation hints from Sir Ronald A. Fisher. Multivariate Behavioral Research, 45, 725–745. doi:10.1080/00273171.2010.498294[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]). These derivative estimation procedures can be used in a two-stage process to fit mixed effects ordinary differential equation (ODE) models. While the performance and utility of these routines for estimating linear ODEs have been established, they have not yet been evaluated in the context of nonlinear ODEs with mixed effects. We compared properties of the GLLA and GOLD to an FDA-based two-stage approach denoted herein as functional ordinary differential equation with mixed effects (FODEmixed) in a Monte Carlo (MC) study using a nonlinear coupled oscillators model with mixed effects. Simulation results showed that overall, the FODEmixed outperformed both the GLLA and GOLD across all the embedding dimensions considered, but a novel use of a fourth-order GLLA approach combined with very high embedding dimensions yielded estimation results that almost paralleled those from the FODEmixed. We discuss the strengths and limitations of each approach and demonstrate how output from each stage of FODEmixed may be used to inform empirical modeling of young children’s self-regulation.     

Religion and Spirituality among American Indian,South Asian,Black, Hispanic/Latina,and White Women in the Study on Stress,Spirituality, and Health

Social scientists have increasingly recognized the lack of diversity in survey research on American religion, resulting in a dearth of data on religion and spirituality (R/S) in understudied racial and ethnic groups. At the same time, epidemiological studies have increasingly diversified their racial and ethnic representation, but have collected few R/S measures to date. With a particular focus on American Indian and South Asian women (in addition to Blacks, Hispanic/Latinas, and white women), this study introduces a new effort among religion and epidemiology researchers, the Study on Stress, Spirituality, and Health. This multicohort study provides some of the first estimates of R/S beliefs and practices among American Indians and U.S. South Asians, and offers new insight into salient beliefs and practices of diverse racial/ethnic and religious communities.     

A Pedagogy of the Parasite

Studies in Philosophy and Education - In the South Korean film, The Parasite, the underling family, in an act of desperation, uses deceptive means to infiltrate the rich family. The term parasite...     

Pilot Trial of Acceptance-Based Behavioral Weight Loss and Neurocognition Among American Indians

Acceptance-based behavioral therapies (ABTs) for obesity may be superior to standard behavioral therapies but have not been adequately tested with American Indians (AIs). Neurocognitive function is also unexamined in relation to behavioral weight loss among AIs despite findings that neurocognition predicts outcomes in general samples, may help explain some of the benefits of ABTs, and may be relevant to marginalized groups. The primary objective of this pilot was to examine the feasibility/acceptability of ABT in an AI sample. Exploratory analyses examined the relationship between neurocognition and weight loss. Forty-eight AI adults with overweight/obesity (ages 43.3 ± 10.3 years, 85% female; baseline body mass index = 36.8 ± 4.4 kg/m²) enrolled in a 6-month open ABT weight loss trial. Feasibility indices, including screening/enrollment, session attendance, retention rates for posttreatment assessments, and program acceptability were examined. Percent weight loss (%WL) was assessed as well as fluid and crystalized neurocognition (National Institutes of Health Toolbox Cognition Battery [NIHTB-CB]). We enrolled 79% of the eligible sample and retained 75% (N = 36) at posttreatment assessments. Program completers lost an average of 5.2 ± 4.9% of initial body weight (d_z = 1.14), whereas intent-to-treat analyses show a mean loss of 4.1 ± 4.7%. Participants reported high satisfaction, effectiveness, and cultural appropriateness. Exploratory analyses of neurocognitive domains suggested that crystalized cognition was higher among completers, and higher baseline cognitive flexibility predicted greater %WL (β = .34, p = .05). ABT resulted in clinically significant weight loss in an AI sample. A controlled trial of ABT in a larger, more diverse sample is warranted to determine whether (a) the findings are robust, generalizable, and/or superior to other treatments and (b) neurocognitive factors moderate outcomes.     

Prospective Associations Between Sleep Disturbance and Repetitive Negative Thinking: The Mediating Roles of Focusing and Shifting Attentional Control

Although considerable evidence has linked sleep disturbance to symptoms of psychopathology, including repetitive negative thinking, few studies have examined how sleep disturbance may predict repetitive negative thinking over time. Further, no study to date has examined specific mechanisms that may account for this relationship. The present study sought to address these gaps in the literature by testing focusing and shifting attentional control as two potential mediators of the relationship between sleep disturbance and repetitive negative thinking over a 6-month period. A final sample of 445 unselected community participants completed measures of sleep disturbance and repetitive negative thinking at Time 1, measures of focusing and shifting attentional control 3 months later, and measures of repetitive negative thinking again 6 months later. Results revealed that focusing, but not shifting, attentional control mediated the relationship between sleep disturbance and repetitive negative thinking, specifically, worry, rumination, and obsessions. These findings provide preliminary evidence for focusing attentional control as a candidate mechanism that may explain the causal role of sleep disturbance in the development of repetitive negative thinking observed in various disorders.     

Using latent class growth analysis to form trajectories of premorbid adjustment in schizophrenia

Premorbid adjustment varies widely among individuals with schizophrenia and has been shown to bear significantly on prodrome and onset characteristics, and on cognition, symptoms, and functioning after onset. The current analysis focused on the Premorbid Adjustment Scale, a retrospective measure assessing social and academic function at several time points from early childhood to illness onset. In an effort to explore discrete developmental subtypes, we applied latent class growth analysis to data from the Premorbid Adjustment Scale in our sample of individuals with schizophrenia (N = 208), finding three latent trajectory classes. The first of these classes showed consistently adequate-to-good social and academic functioning before onset; the second showed initially good function and deterioration with time until onset; the third showed poor functioning in childhood that deteriorated further during the years up to diagnosis. The classes differed significantly in terms of age of onset, processing speed, and functioning after onset. There were no significant differences in symptomatology. Our findings illustrate a potentially powerful methodological approach to the problem of heterogeneity in schizophrenia research, and add weight to the notion that aspects of premorbid history may be useful for subtyping schizophrenia patients. The potential implications of this subtyping strategy, including those pertaining to potential genetics studies, are discussed.     

Mothers' affect dysregulation,depressive symptoms,and emotional availability during mother–infant interaction

Maternal affect dysregulation and maternal depressive symptoms were examined as predictors of maternal emotional availability (EA) during mother–infant interaction in a nonclinical sample. In particular, we investigated if affect dysregulation predicts EA and is more important than are depressive symptoms in predicting EA. Questionnaire measures and 30 min of free play were obtained from 46 mothers of 4‐ to 5‐month‐old infants. Mothers' self‐reported affect dysregulation was inversely related to EA, but mothers' depressive symptoms were not related to EA. More specifically, mothers' tendency to use unhealthy externalizing behaviors to reduce tension and distress predicted less EA. These results suggested that even in relatively low‐risk samples, mothers' self‐reported affect dysregulation, particularly the tendency to act out inappropriately in response to tension and distress, may be a more proximal predictor of EA than are depressive symptoms.     

Speech presentation cues moderate frontal EEG asymmetry in socially withdrawn young adults

Socially withdrawn individuals display solitary behavior across wide contexts with both unfamiliar and familiar peers. This tendency to withdraw may be driven by either past or anticipated negative social encounters. In addition, socially withdrawn individuals often exhibit right frontal electroencephalogram (EEG) asymmetry at baseline and when under stress. In the current study we examined shifts in frontal EEG activity in young adults (N=41) at baseline, as they viewed either an anxiety-provoking or a benign speech video, and as they subsequently prepared for their own speech. Results indicated that right frontal EEG activity increased, relative to the left, only for socially withdrawn participants exposed to the anxious video. These results suggest that contextual affective cues may prime an individual's response to stress, particularly if they illustrate or substantiate an anticipated negative event.     

The effect of restraint beliefs on alcohol-seeking behavior

Individuals who believe that they have high levels of restraint over motivated behaviors such as cigarette smoking are, paradoxically, more likely to engage in those behaviors when tempted (Nordgren, Van Harreveld, & Van Der Pligt, 2009). Our aim was to experimentally manipulate heavy drinkers' beliefs about their drinking restraint to examine the effect on drinking behavior. Sixty heavy drinkers completed an implicit association test and a stop-signal task before receiving bogus feedback on their task performance that indicated that they had either high or low levels of drinking restraint. Participants then completed a bogus taste test in which they were able to consume beer and a soft drink. Results indicated that the group falsely led to believe that they had a high level of drinking restraint subsequently consumed more beer than the group led to believe that they had a low level of drinking restraint. This study demonstrates that beliefs about drinking restraint can influence drinking behavior, in that individuals who overestimate their control over drinking are at greater risk of drinking to excess when exposed to tempting situations.