Exploring the dynamics of design fluency in children with and without ADHD using artificial neural networks

The neuropsychology of attention deficit/hyperactivity disorder (ADHD) has been extensively studied, with a general focus on global performance measures of executive function. In this study, we compared how global (i.e., endpoint) versus process (i.e., dynamic) measures of performance may help characterize children with and without ADHD using a design fluency task as a case study. The secondary goal was to compare the sensitivity of standard versus connectionist statistical models to group differences in cognitive data. Thirty-four children diagnosed with ADHD and 37 children without ADHD aged 8–11 years old were tested on the Five-Point Test. The continuous process measure of performance, indexed as the number of produced designs at each consecutive 1 minute interval during 5 minutes, was analyzed against the discrete process measure, that is, the number of designs between first and last intervals and the standard global performance measure of total number of produced designs. Results show that the continuous process measure distinguished the two groups better than the two other measures. The detailed observation of production patterns revealed a decreasing linear trajectory in children without ADHD that contrasts with the flat, but fluctuating productivity pattern of children with ADHD. With regards to the second goal, results show that the connectionist and standard methods are equally sensitive to group differences for the three types of measures. This illustrates the utility of quantitative process measures together with the connectionist method in neuropsychological research and suggests great potential for a dynamical approach to cognition.     

Executive function and psychosocial adjustment in healthy children and adolescents: A latent variable modelling investigation

The objective of this study was to establish latent executive function (EF) and psychosocial adjustment factor structure, to examine associations between EF and psychosocial adjustment, and to explore potential development differences in EF-psychosocial adjustment associations in healthy children and adolescents. Using data from the multisite National Institutes of Health (NIH) magnetic resonance imaging (MRI) Study of Normal Brain Development, the current investigation examined latent associations between theoretically and empirically derived EF factors and emotional and behavioral adjustment measures in a large, nationally representative sample of children and adolescents (7–18 years old; N = 352). Confirmatory factor analysis (CFA) was the primary method of data analysis. CFA results revealed that, in the whole sample, the proposed five-factor model (Working Memory, Shifting, Verbal Fluency, Externalizing, and Internalizing) provided a close fit to the data, χ²(66) = 114.48, p < .001; RMSEA = .046; NNFI = .973; CFI = .980. Significant negative associations were demonstrated between Externalizing and both Working Memory and Verbal Fluency (p < .01) factors. A series of increasingly restrictive tests led to the rejection of the hypothesis of invariance, thereby precluding formal statistical examination of age-related differences in latent EF-psychosocial adjustment associations. Findings indicate that childhood EF skills are best conceptualized as a constellation of interconnected yet distinguishable cognitive self-regulatory skills. Individual differences in certain domains of EF track meaningfully and in expected directions with emotional and behavioral adjustment indices. Externalizing behaviors, in particular, are associated with latent Working Memory and Verbal Fluency factors.     

The effect of identical word pairs on people's metamemory judgments: What are the contributions of processing fluency and beliefs about memory?

Judgments of learning (JOLs) are higher for identical pairs (dog–dog) than for related pairs (dog–cat). This identical effect may be mediated (a) by processing fluency (i.e., identical pairs are processed faster than related pairs) or (b) by a belief that identical pairs are better remembered or (c) by both factors. In the present work, we assessed the contribution of both factors. We evaluated whether a measure of processing fluency (i.e., self-paced study) mediated the relationship between pair type and JOLs (Experiment 1) and attempted to disrupt processing fluency using an AlTeRnAtInG presentation format (Experiment 2). We also evaluated whether judgments made in the absence of processing fluency demonstrated the identical effect (Experiment 3), and, finally, we had participants read a vignette about an experiment that included both pair types and estimate which pairs would be best remembered (Experiment 4). Evidence from all experiments converged on the conclusion that people's beliefs about how variables affect memory—and not differential fluency—best explain the identical effect, although we cannot entirely rule out the possibility that fluency plays a small role. The outcomes were consistent with the analytic-processing theory of JOLs—namely, when instructed to make JOLs, people adopt an analytic problem-solving approach that involves identifying variation across pairs that plausibly relate to memory and then use this variation to make JOLs.     

A latent variable approach to executive control in healthy ageing

It is a well-established finding that the central executive is fractionated in at least three separable component processes: Updating, Shifting, and Inhibition of information (Miyake et al., 2000). However, the fractionation of the central executive among the elderly has been less well explored, and Miyake's et al. latent structure has not yet been integrated with other models that propose additional components, such as access to long-term information. Here we administered a battery of classic and newer neuropsychological tests of executive functions to 122 healthy individuals aged between 48 and 91 years. The test scores were subjected to a latent variable analysis (LISREL), and yielded four factors. The factor structure obtained was broadly consistent with Miyake et al.'s three-factor model. However, an additional factor, which was labeled 'efficiency of access to long-term memory', and a mediator factor ('speed of processing') were apparent in our structural equation analysis. Furthermore, the best model that described executive functioning in our sample of healthy elderly adults included a two-factor solution, thus indicating a possible mechanism of dedifferentiation, which involves larger correlations and interdependence of latent variables as a consequence of cognitive ageing. These results are discussed in the light of current models of prefrontal cortex functioning.     

Clinical Validity and Interpretation of the Gordon Diagnostic System in ADHD Assessments

Gordon Diagnostic System (GDS) data were analyzed for 165 referred children with ADHD combined type and 46 referred children without ADHD, 6–16 years of age. Results showed significant differences between children with and without ADHD on the GDS standard scores and the IQ-GDS differences scores. Using a GDS composite standard score of 13 points or more below IQ to classify children as having ADHD resulted in the highest diagnostic accuracy (86%), with positive predictive power equal to 91%, and negative predictive power 67%. Results for the GDS compared favorably with those reported for other continuous performance tests. The findings lend support to the GDS as a clinically useful component of an ADHD evaluation.     

Normative Impulsivity: Adorno on Ethics and the Body

Abstract

Adorno’s commitment to anti-foundationalism generates a concern over how his ethically normative appraisals of social phenomena can be founded. Drawing on both Kohlmann and Bernstein’s account, I produce a new reading which contends somatic impulses are capable of bearing intrinsically normative epistemic and moral content. This entails a new way of understanding Adorno’s contention that Auschwitz produced a new categorical imperative. Working with Bernstein’s account, I claim that Auschwitz makes manifest the hostility of the instrumentalization of reason to the somatic grounds of reason. One’s mimetic identification with the victims of Auschwitz arouses a self-preserving desire to intercede in and re-orient the progress of reason itself, for the sake of one’s own somatic integrity. In closing, I claim – contra Zuidervaart – that this reading allows us to place the ethical as primary in Adorno, without reducing the political to it.     

Performance on a measure of category fluency in cognitively impaired elderly

ABSTRACT

Measures of verbal fluency are widely used in the assessment of cognitive functioning of the elderly. However, limited research has evaluated patterns (across specific timed intervals) of performance on tasks of language fluency in different forms of dementia. The current study investigated semantic fluency in 488 elderly individuals (249 with Alzheimer's dementia, 97 Vascular dementia, 97 Mild Cognitive Impairment and 45 cognitively intact) across 15-second intervals in an animal naming task using retrospective chart review. Normal controls produced significantly more exemplars and AD patients produced fewer animal names than the other groups. After the first 15- second time interval, the demented groups produced significantly fewer exemplars than the non-demented. At the end of 30 seconds it was possible to differentiate normal aging from MCI who no longer differed from the VaD group. Overall, it appears that the greatest and most clinically meaningful differences between the diagnostic groups were detected in the first three 15-second intervals. The present findings support the use of time intervals and total scores on tasks of verbal fluency in clinical settings and for research purposes.     

Verbal fluency and creativity: General and specific contributions of broad retrieval ability (Gr) factors to divergent thinking

The Cattell–Horn–Carroll (CHC) model of intelligence views creativity as a first-level factor within the second-level factor of broad retrieval ability (Gr), alongside other first-level abilities such as ideational fluency and word fluency. Traditional methods of measuring creativity, however, confound idea quality with idea quantity, which might exaggerate the relationship between creativity scores and verbal fluency factors. Participants (n = 131 adults) completed two divergent thinking tasks (unusual uses for a rope and a box), which were scored using newer methods that effectively separate creativity (scored via subjective ratings) and fluency (scored as number of responses). They then completed 16 verbal fluency tasks that assessed six lower-order Gr factors: word fluency, associational fluency, associative flexibility, ideational fluency, letter fluency, and dissociative ability. Viewed singly, many of the lower-order factors significantly predicted creative quality and fluency. General Gr had substantial effects on creative quality (standardized β = .443) and fluency (β = .339) in a higher-order model as well as in a bifactor model (quality β = .380, fluency β = .327). Moreover, general Gr was the only significant predictor in the bifactor model, suggesting that it, not the specific factors, was most important. All effects were essentially the same after controlling for typing speed and vocabulary knowledge. The findings thus support the CHC view of creativity/originality as a lower-order component of Gr, illuminate the relationships between creativity and first-level Gr factors, extend the study of creativity and intelligence beyond fluid intelligence, and further indicate that creativity is more closely tied to cognitive abilities than creativity research has yet recognized.     

So many options,so little control: Abstract representations can reduce selection demands to increase children’s self-directed flexibility

Children often struggle to behave flexibly when they must use self-directed goals (e.g., doing homework without prompting) rather than externally driven goals (e.g., cleaning up when told). Such struggles may reflect the demands of selecting among many potential options, as required for self-directed control. The current study tested whether (a) 6-year-old children show difficulty in selecting among competing semantic representations, (b) providing category labels designed to reduce selection demands improves performance, and (c) such benefits transfer to self-directed flexibility. Selection was measured using the blocked cyclic naming task for the first time with children. Pictures were named repeatedly in either homogeneous blocks from the same category (e.g., all animals), which create high selection demands due to spreading semantic activation and engage effortful cognitive control, or mixed blocks with each picture from a different category. Children showed robust difficulty in selecting among options, as indexed by response time (RT) differences between homogeneous and mixed blocks. Providing subcategory labels designed to reduce selection demands by distinguishing among same-category items (e.g., “A cow is a farm animal. A cat is a pet.”) improved selection. Providing superordinate categories (e.g., “A cow is an animal. A cat is an animal.”) also improved selection, but these benefits were less robust, and subcategory labels led to greater benefits than superordinate category labels on a subsequent verbal fluency task. These results support a role for subcategory representations in reducing selection demands to aid self-directed flexibility while suggesting that some children may use superordinate category labels to activate subcategory representations on their own.