Increased intraindividual variability is a marker of ADHD but also of dyslexia: a study on handwriting

It has been suggested that intraindividual variability (IIV) in neuropsychological tasks may be a specific characteristic of Attention-Deficit Hyperactivity Disorder (ADHD), but previous research has not thoroughly examined whether IIV also concerns academic performance or other types of developmental disabilities. The present study investigates the role of IIV in 15 children with ADHD without reading difficulties, 15 children with dyslexia without associated symptoms of ADHD, and 15 typically developing children (TDC) in a simple response time (SRT) task and in a skill more directly related with school learning—handwriting. Results show that children with ADHD and those with dyslexia have a greater IIV than the TDC in both tasks. However, the pattern of the relationship between IIV in SRT and handwriting was different in children with ADHD and dyslexia: the IIV in the handwriting task was found to depend on IIV in the SRT task only in children with dyslexia. These findings support the crucial role of IIV not only in ADHD but also in other developmental disabilities, but suggest that in children with ADHD it may present specific aspects related with motor control.     

Time of Day Affects Episodic Memory in Older Adults*

ABSTRACT

The neuropsychological test scores of 2,030 cognitively normal older adults were examined to evaluate performance patterns as they related to time of day (TOD) at which testing was initiated. Multiple regression analyses were used to examine the association of TOD with scores on seven neuropsychological tests used in the clinical evaluation of dementia. Episodic memory performance was significantly related to TOD, while memory span and verbal fluency were not. Best performance occurred during early morning hours and late afternoon; worst performance occurred mid-day (i.e., noon). These findings may have implications for clinical assessment, the design of research on dementia, and the daily functioning of older adults.     

Does within-person variability predict errors in healthy adults aged 18–90?

This study investigated within-person variability on basic psychomotor tasks in relation to errors on a higher order cognitive task. We were interested in whether more variable individuals were more prone to making errors, and whether this relationship varied with age. Variability was assessed using simple and choice reaction time, while errors of omission (misses) and commission (false alarms) were obtained from simple and complex visual search tasks. Data from 557 participants aged 18–90 years were included in the analysis. Greater variability was associated with more misses, and distribution analyses showed that slower responses were behind this effect. Variability was also associated with false alarms, but the pattern was inconsistent. Taking age into account revealed that the association between variability and misses in the simple visual search condition was stronger in older (aged 65–90 years) participants. The results suggest the relationship between greater variability and errors of omission (misses) may be related to inattention. Measures of variability may therefore provide valuable insights into individual differences in error rates and, more broadly, may also offer early warning of persons who are more prone to errors in visual search.     

Assessing within-person personality variability via frequency estimation: More evidence for a new measurement approach

Variability in personality has been recognized in recent years as an important aspect of personality both conceptually and empirically. A relatively new and efficient method of obtaining variability information is frequency-based personality assessment (Edwards & Woehr, 2007). The purpose of the present research is to further examine the viability of frequency-based personality measurement as an alternative to traditional (Likert-type) measurement and to assess the usefulness of the variance-based parameters. Toward this end, three studies are presented. Specifically, Study 1 examined relationships between a frequency-based measure of the Big Five personality traits and several motivational variables. Study 2 examined the moderating role of temporal consistency information (provided by frequency-based measurement) on relationships between personality and peer ratings of task performance. Study 3 compared the frequency-based measure to a Likert-type measure with respect to each measure’s susceptibility to deliberate response distortion. Results indicated that consistency information increases the predictive validity of agreeableness and conscientiousness and that a frequency-based format is less susceptible to faking than a Likert-type format for conscientiousness, emotional stability, and openness to experience.     

Your personality on a good day: How trait and state personality predict daily well-being

The dynamic mediation model (Wilt, Noftle, Fleeson, & Spain, 2012) explains the associations between personality traits and happiness through links between personality states and daily well-being. To test this model, and the mediators of these relations, we examined if between- and within-person variation in personality was associated with daily well-being for undergraduates (N = 133) and US adults (N = 117). The model explained the trait neuroticism and daily well-being association. Also, after controlling for traits, people were happier on days in which they were extraverted, agreeable, conscientious, emotionally stable, and open to experience. Finally, these associations were partially mediated by the satisfaction of daily psychological needs. We discuss how the operationalization of state extraversion might impact its relation with daily well-being.     

Daily fluctuations in perfectionism dimensions and their relation to eating disorder symptoms

Multidimensional perfectionism has been shown to play an important role in eating disorders (EDs). However, research examining this relation has primarily focused on relatively stable inter-individual differences between persons, thereby failing to examine how these variables are associated within individuals on a daily basis. This study examines how daily fluctuations in Personal Standards (PS) perfectionism and Evaluative Concerns (EC) perfectionism relate to each other and to fluctuations in ED symptoms. Adolescents (N = 275) completed questionnaires each evening during seven consecutive days. Multilevel modeling showed significant day-to-day fluctuations in PS and EC perfectionism, and showed that both dimensions are intertwined in the day. Among females, fluctuations in EC perfectionism co-varied with fluctuations in ED symptoms.     

儿童逻辑关系认知发展的实验研究

通过追踪研究和横断研究相结合的方法研究７岁、９岁和１２岁儿童的逻辑关系认知能力的发展。结果表明：儿童的认知成绩随着年龄的增长而提高,不同项目间差异很大,而且不同实验项目有不同的发展速度。儿童间的个别差异也很大,这主要与儿童的家庭教育程度以及城市与郊区不同学校教育条件等因素有关,并且儿童的逻辑关系认知能力与儿童的学习能力,学习成绩以及儿童的智力水平有很高的相关。另外儿童的物理逻辑认知并非都按固定不变的顺序发展。     

Tryptophan and interpersonal spin

Increased serotonergic activity is often described as increasing the inhibition of behaviors. This study examined the more general hypothesis that increased serotonergic activity produces greater control over social behavior. Participants were drawn from two samples, individuals elevated on irritability and individuals unselected on personality characteristics. Individuals participated in a double blind cross-over design, providing event contingent records about their behavior during two 9-day periods which involved taking tryptophan or placebo. When taking tryptophan (which increases serotonergic activity), within-person variability among social behaviors across events (i.e., interpersonal spin) was reduced for irritable individuals, particularly those low on trait Agreeableness. These results suggest that higher levels of serotonergic activity enhance greater control and consistency in social behavior among irritable–disagreeable individuals.     

A foundation beam for studying morality from a personological point of view: Are individual differences in moral behaviors and thoughts consistent?

Morality is a topic of burgeoning scientific interest, and the relevance of personological factors to moral behavior has interdisciplinary implications for the social sciences, public policy, and philosophy. However, relatively little research has investigated the role of personological factors in moral life, perhaps because of lingering skepticism about the robustness of moral traits. The purpose of this paper is to determine whether morality is consistent across many occasions of everyday life, implying that personological factors play an important role in moral behavior. A novel method of assessing moral behaviors was developed and employed in two experience sampling studies (4075 total observations). Results showed that moral behavior is consistent in many different ways, suggesting that personological factors substantially impact moral life.     

Cognitive predictors of single-digit and procedural calculation skills and their covariation with reading skill

This study examined the extent to which children's cognitive abilities in kindergarten and their mothers' education predict their single-digit and procedural calculation skills and the covariance of these with reading skill in Grade 4. In kindergarten, we assessed children's (N=178) basic number skills, linguistic skills, and visual attention. In Grade 4, we assessed their calculation and reading skills. Data on children's cognitive ability at 5 years of age and their mothers' level of education were also collected. The results showed that both of the core components of calculation, single-digit and procedural calculation, as well as their covariance with reading, were predicted by unique cognitive factors. Fluency in single-digit calculation and text reading shared an underlying cognitive process, that is, the ability to fluently retrieve verbal or visual-verbal associations from long-term memory. In contrast, procedural calculation was predicted not only by single-digit calculation but also by mother's education and conceptual knowledge of numbers. Overall, the results suggest that a multicomponential approach, including a hierarchical relation among various components, is fruitful when trying to understand the development of mathematical skill and its covariation with reading.     

Intraindividual reaction time variability predicts prospective memory failures in older adults

This study investigated the relationship between intraindividual variability (IIV) in reaction time and prospective memory errors in older adults using data from the Zurich Longitudinal Study of Cognitive Aging (n = 336 individuals aged 66–81 years). The results indicated that increased IIV measured from independent tasks was associated with a greater proportion of prospective memory errors. These significant findings were not influenced by age and did not vary according to prospective memory cue type. Variability is thought to reflect fluctuations in attentional and executive control and these attentional processes may also impact on prospective memory through failure to detect the target cue. The findings suggest, therefore, that measures of variability may have some potential in the identification of older persons who are more vulnerable to everyday errors such as prospective memory failures.