Proportion Of Variance In Measures Research Articles

Evaluating circumlocution in naming as a predictor of communicative informativeness and efficiency in discourse

ABSTRACT Background Discourse analyses yield quantitative measures of functional communication in aphasia. However, they are historically underutilized in clinical settings. Confrontation naming assessments are used widely clinically and have been used to estimate discourse-level production. Such work shows that naming accuracy explains moderately high proportions of variance in measures of discourse, but proportions of variance remain unexplained. We propose that the inclusion of circumlocution productions into predictive models will account for a significant amount more of the variance. Circumlocution productions at the naming-level, while they may not contain the target word, are similar to the content that contributes to discourse informativeness and efficiency. Thus, additionally measuring circumlocution may improve our ability to estimate discourse performance and functional communication. Aim This study aimed to test whether, after controlling for naming accuracy, the addition of a measure of circumlocution into predictive models of discourse-level informativeness and efficiency would account for a significant amount more of the variance in these discourse-level outcomes. Methods & Procedures Naming and discourse data from 43 people with poststroke aphasia were analyzed. Naming data were collected using 120 pictured items and discourse data were collected using two picture description prompts. Data scoring and coding yielded measures of naming accuracy, incorrect response type, communicative informativeness, and efficiency. We used robust hierarchical regression to evaluate study predictions. Outcomes & Results After controlling for naming accuracy, the inclusion of circumlocution into predictive models accounted for a significant amount more of the variance in both informativeness and efficiency. The subsequent inclusion of other response types, such as real word and nonword errors, did not account for a significant amount more of the variance in either outcome. Conclusions In addition to naming accuracy, the production of circumlocution during naming assessments may correspond with measures of informativeness and efficiency at the discourse-level. Reducing the burden of estimating patients’ functional communication will increase our ability to estimate functional communication using tools that are easy to administer and interpret.

Charting the contributions of cognitive flexibility to creativity: Self-guided transitions as a process-based index of creativity-related adaptivity.

Creativity is pivotal to solving complex problems of many kinds, yet how cognitive flexibility dynamically supports creative processes is largely unexplored. Despite being a crucial multi-faceted contributor in creative thinking, cognitive flexibility, as typically assessed, does not fully capture how people adaptively shift between varying or persisting in their current problem-solving efforts. To fill this theoretical and methodological gap, we introduce a new operationalization of cognitive flexibility: the process-based Self-Guided Transition (SGT) measures, which assess when participants autonomously choose to continue working on one of two concurrently presented items (dwell length) and how often they choose to switch between the two items (shift count). We examine how these measures correlate with three diverse creativity tasks, and with creative performance on a more complex "garden design" task. Analyses of the relations between these new cognitive flexibility measures in 66 young adults revealed that SGT dwell length positively correlated with creative performance across several tasks. The SGT shift count positively correlated with within-task performance for a two-item choice task tapping divergent thinking (Alternative Uses Task) but not for a two-item choice task calling on convergent thinking (Anagram task). Multiple regression analyses revealed that, taken together, both the shift count and dwell length measures from the Alternative Uses Task explained a significant proportion of variance in measures of fluency, and originality, on a composite measure of the three independently-assessed creative tasks. Relations of SGTs to the Garden Design task were weaker, though shift count on the Alternative Uses Task was predictive of a composite measure of overall Garden Design quality. Taken together, these results highlight the promise of our new process-based measures to better chart the dynamically flexible processes supporting creative thinking and action.

Associations Between Heart Rate Variability Measured With a Wrist-Worn Sensor and Older Adults' Physical Function: Observational Study.

BackgroundHeart rate variability (HRV), or variation in beat-to-beat intervals of the heart, is a quantitative measure of autonomic regulation of the cardiovascular system. Low HRV derived from electrocardiogram (ECG) recordings is reported to be related to physical frailty in older adults. Recent advances in wearable technology offer opportunities to more easily integrate monitoring of HRV into regular clinical geriatric health assessments. However, signals obtained from ECG versus wearable photoplethysmography (PPG) devices are different, and a critical first step preceding their widespread use is to determine whether HRV metrics derived from PPG devices also relate to older adults’ physical function.ObjectiveThis study aimed to investigate associations between HRV measured with a wrist-worn PPG device, the Empatica E4 sensor, and validated clinical measures of both objective and self-reported physical function in a cohort of older adults living independently within a continuing care senior housing community. Our primary hypothesis was that lower HRV would be associated with lower physical function. In addition, we expected that HRV would explain a significant proportion of variance in measures of physical health status.MethodsWe evaluated 77 participants from an ongoing study of older adults aged between 65 and 95 years. The assessments encompassed a thorough examination of domains typically included in a geriatric health evaluation. We collected HRV data with the Empatica E4 device and examined bivariate correlations between HRV quantified with the triangular index (HRV TI) and 3 widely used and validated measures of physical functioning—the Short Physical Performance Battery (SPPB), Timed Up and Go (TUG), and Medical Outcomes Study Short Form 36 (SF-36) physical composite scores. We further investigated the additional predictive power of HRV TI on physical health status, as characterized by SF-36 physical composite scores and Cumulative Illness Rating Scale for Geriatrics (CIRS-G) scores, using generalized estimating equation regression analyses with backward elimination.ResultsWe observed significant associations of HRV TI with SPPB (n=52; Spearman ρ=0.41; P=.003), TUG (n=51; ρ=−0.40; P=.004), SF-36 physical composite scores (n=49; ρ=0.37; P=.009), and CIRS-G scores (n=52, ρ=−0.43; P=.001). In addition, the HRV TI explained a significant proportion of variance in SF-36 physical composite scores (R2=0.28 vs 0.11 without HRV) and CIRS-G scores (R2=0.33 vs 0.17 without HRV).ConclusionsThe HRV TI measured with a relatively novel wrist-worn PPG device was related to both objective (SPPB and TUG) and self-reported (SF-36 physical composite) measures of physical function. In addition, the HRV TI explained additional variance in self-reported physical function and cumulative illness severity beyond traditionally measured aspects of physical health. Future steps include longitudinal tracking of changes in both HRV and physical function, which will add important insights regarding the predictive value of HRV as a biomarker of physical health in older adults.

Nutrient biomarker patterns, cognitive function, and fMRI measures of network efficiency in the aging brain

A central aim of research in the psychological and brain sciences is to establish therapeutic interventions to promote healthy brain aging. Accumulating evidence indicates that diet and the many bioactive substances present in food are reasonable interventions to examine for dementia prevention. However, interdisciplinary research that applies methods from nutritional epidemiology and network neuroscience to investigate the role of nutrition in shaping functional brain network efficiency remains to be conducted. The present study therefore sought to combine methods across disciplines, applying nutrient biomarker pattern (NBP) analysis to capture the effects of plasma nutrients in combination and to examine their collective influence on measures of functional brain network efficiency (small-world propensity). We examined the contribution of NBPs to multiple indices of cognition and brain health in non-demented elders (n = 116), investigating performance on measures of general intelligence, executive function, and memory, and resting-state fMRI measures of brain network efficiency within seven intrinsic connectivity networks. Statistical moderation investigated whether NBPs influenced network efficiency and cognitive outcomes. The results revealed five NBPs that were associated with enhanced cognitive performance, including biomarker patterns high in plasma: (1) ω-3 and ω-6 polyunsaturated fatty acids (PUFAs), (2) lycopene, (3) ω-3 PUFAs, (4) carotenoids, and (5) vitamins B (riboflavin, folate, B12) and D. Furthermore, three NBPs were associated with enhanced functional brain network efficiency, including biomarker patterns high in plasma: (1) ω-6 PUFAs, (2) ω-3 PUFAs, and (3) carotene. Finally, ω-3 PUFAs moderated the fronto-parietal network and general intelligence, while ω-6 PUFAs and lycopene moderated the dorsal attention network and executive function. In sum, NBPs account for a significant proportion of variance in measures of cognitive performance and functional brain network efficiency. The results motivate a multidisciplinary approach that applies methods from nutritional epidemiology (NBP analysis) and cognitive neuroscience (functional brain network efficiency) to characterize the impact of nutrition on human health, aging, and disease.

Recent advances in understanding the neurobiology of childhood socioeconomic disadvantage.

To provide an update of recent research regarding neural mechanisms of socioeconomic disadvantage. The studies reviewed provide convincing evidence of the detrimental effects of early adversities on brain structure and function. The effects of socioeconomic disadvantage and related environmental risks, such as childhood adversity and smoking during pregnancy, while affecting distributed networks of brain regions, have decreased prefrontal activity and volume as a common feature. Recent work suggests that socioeconomic disadvantage and related risk factors may account for a significant proportion of variance in measures of brain structure and function, which may mediate the increased risk of psychopathology. Impaired prefrontal control may be a convergent mechanism underlying early exposure to socioeconomic risk factors in humans. Environmental imaging, that is, the impact which environmental adversity may have on brain structure and function, has only recently moved into the focus of interest. This is surprising because the link to psychopathology has long since been acknowledged and socioeconomic risk factors are modifiable, meaning that understanding their mechanism may point toward prevention and early intervention mechanisms. In future work, the interplay between different environmental risk factors, their potential epigenetic mechanisms, and their interaction with genetic risk should be studied.

An Adapted Word-Sentence Association Paradigm for Generalized Anxiety and Worry: Assessing Interpretation Bias

Individuals with pathological worry, a common symptom of Generalized Anxiety Disorder (GAD), make threatening interpretations of ambiguous information related to various life domains (e.g., finances, relationships). A word-sentence association paradigm (WSAP) computer task, originally designed for social anxiety, was adapted to assess two threat-related interpretation biases common among individuals with generalized anxiety and pathological worry. The two biases, which have yet to be investigated simultaneously, include: accepting threatening interpretations and rejecting benign interpretations of ambiguous information (for the original WSAP, see Beard & Amir, 2009). It was hypothesized that endorsing threat interpretations on the WSAP would be associated with greater bias for threat on a validated self-report measure of bias, and would predict GAD symptoms and worry after trait anxiety and depression were statistically controlled. Results from a non-clinical sample (N = 148) provided support for the convergent validity of the WSAP. After controlling for trait anxiety and depression, a bias to accept threat interpretations predicted a unique and significant proportion of variance in measures of GAD symptoms and worry. A bias away from non-threat (i.e., rejecting benign interpretations) was unrelated. The WSAP shows evidence of sensitivity and specificity to GAD symptoms and worry, and appears to be a unique and specific measure of two types of threat bias making it theoretically informative and clinically useful.

Physically Abused Children's Adjustment at the Transition to School: Child, Parent, and Family Factors.

Childhood physical abuse predicts emotional/behavioral, self-regulatory, and social problems. Yet factors from multiple ecological levels contribute to children's adjustment. The purpose of this study was to examine the degree to which the social-emotional adjustment of physically abused children in first grade would be predicted by a set of child-, parent-, and family-level predictors in kindergarten. Drawing on a short-term longitudinal study of 92 physically abused children and their primary caregivers, the current study used linear regression to examine early childhood child (i.e., gender, IQ, child perceptions of maternal acceptance), parent (i.e., parental mental health), and family relationship (i.e., sensitive parenting, hostile parenting, family conflict) factors as predictors of first grade internalizing and externalizing symptomatology, emotion dysregulation, and negative peer interactions. We used a multi-method, multi-informant approach to measuring predictors and children's adjustment. Internalizing symptomatology was significantly predicted by child IQ, parental mental health, and family conflict. Externalizing symptomatology and emotion dysregulation were predicted by child IQ. Although a large proportion of variance in measures of adjustment was accounted for by the set of predictors, few individual variables were unique predictors of child adjustment. Variability in the predictors of adjustment for physically abused children underscores the need for individualized treatment approaches.

Genetic Risks and ADHD Symptomatology: Exploring the Effects of Parental Antisocial Behaviors in an Adoption-Based Study

A great deal of research has examined the etiology of attention-deficit/hyperactivity disorder (ADHD) and ADHD symptomatologies. Genetic factors are consistently shown to explain a significant proportion of variance in measures of ADHD. The current study adds to this body of research by examining whether genetic liabilities for criminality and alcoholism have effects on the development of ADHD symptomatologies. Analyses based on a sample of adoptees drawn from the National Longitudinal Study of Adolescent Health (Add Health) revealed that ADHD symptomatologies were elevated among adoptees who had biological mothers and fathers who had been arrested or who were alcoholics. These results suggest that part of the covariation between ADHD and antisocial behaviors may be the result of genetic factors that have general effects across a range of maladaptive outcomes.

Pain Catastrophizing and Pain-Related Fear in Osteoarthritis Patients: Relationships to Pain and Disability

This study examined the degree to which pain catastrophizing and pain-related fear explain pain, psychological disability, physical disability, and walking speed in patients with osteoarthritis (OA) of the knee. Participants in this study were 106 individuals diagnosed as having OA of at least one knee, who reported knee pain persisting for six months or longer. Results suggest that pain catastrophizing explained a significant proportion (all Ps ≤ 0.05) of variance in measures of pain (partial r 2 [p r 2] = 0.10), psychological disability (p r 2 = 0.20), physical disability (p r 2 = 0.11), and gait velocity at normal (p r 2 = 0.04), fast (p r 2 = 0.04), and intermediate speeds (p r 2 = 0.04). Pain-related fear explained a significant proportion of the variance in measures of psychological disability (p r 2 = 0.07) and walking at a fast speed (p r 2 = 0.05). Pain cognitions, particularly pain catastrophizing, appear to be important variables in understanding pain, disability, and walking at normal, fast, and intermediate speeds in knee OA patients. Clinicians interested in understanding variations in pain and disability in this population may benefit by expanding the focus of their inquiries beyond traditional medical and demographic variables to include an assessment of pain catastrophizing and pain-related fear.

The Relationship of Behavioral Inhibition to Executive Functions in Young Adults

Barkley's hybrid model of executive functions (EFs) predicts that individuals with deficient inhibitory control should show impairment of EFs. Thirty-eight nonreferred young adults were administered tests of EFs and four laboratory measures of inhibitory control: Stop Signal (SS), Go No-Go, Competing Motor Program (CMP), and Stroop Color-Word tests. Behavioral ratings of impulsivity were collected using the Barratt Impulsivity Scale-11 (BIS-11). CMP and SS accounted for a significant proportion of variance in measures of EFs beyond that accounted for by IQ. Additionally, increased impulsivity, as measured by the BIS-11, was associated with poorer performance on some tests of EFs. These findings provide partial support for Barkley's theory in that effective executive functioning is associated with sufficient inhibitory control.

The structure of fundamental fears

Reiss's expectancy theory states that panic attacks, phobias, and other fear reactions arise from three fundamental fears (sensitivities): anxiety sensitivity, fear of negative evaluation, and injury/illness sensitivity. The present study examined two central aspects of the theory: (1) the assumption that fundamental fears are factorially distinct, and (2) the proposition that fundamental fears account for variance in other forms of fear and in trait anxiety. Measures of fundamental fears, common fears, and trait anxiety were administered to 100 community volunteers. The results supported Reiss's theory; the fundamental fears were factorially distinct, minimally intercorrelated, and accounted for significant proportions of variance in measures of other fears and trait anxiety. Specific and conceptually meaningful links were found between fundamental fears and common fears.