Individual Differences In Timing Research Articles

Individual differences in timing of susceptibility to adverse effects of family dysfunction.

Do adolescents vary in the timing of their susceptibility to family-related adversity? Does early exposure to family dysfunction affect later adolescent plasticity? To address these two questions an influence statistic, DFBETAS, was used to capture degree to which 605,344 Danish children (294,479 females, 5.21% immigrants; race/ethnicity information not available in Danish registry) appeared susceptible to the adverse effects of household dysfunction measured annually at ages 0-5 and 13-18 on problematic development at age 18-19. Degree of susceptibility to family-adversity effects proved generally consistent across periods (γ = 0.5195), though for a not insubstantial number of adolescents this was decidedly not the case, as they were highly dissimilar (N = 80,408, 13.28%). Also, greater early-adversity susceptibility did not forecast reduced adolescent susceptibility, as has been hypothesized, but just the opposite. Future research can address the generalizability of these findings. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Investigating the developmental timing of self-regulation in early childhood

Self-regulation often refers to the executive influence of cognitive resources to alter prepotent responses. The ability to engage cognitive resources as a form of executive process emerges and improves in the preschool-age years while the dominance of prepotent responses, such as emotional reactions, begins to decline from toddlerhood onward. However, little direct empirical evidence addresses the timing of an age-related increase in executive processes and a decrease in age-related prepotent responses over the course of early childhood. To address this gap, we examined children’s individual trajectories of change in prepotent responses and executive processes over time. At four age points (24 months, 36 months, 48 months, and 5 years), we observed children (46% female) during a procedure in which mothers were busy with work and told their children they had to wait to open a gift. Prepotent responses included children’s interest in and desire for the gift and their anger about the wait. Executive processes included children’s use of focused distraction, which is the strategy considered optimal for self-regulation in a waiting task. We examined individual differences in the timing of age-related changes in the proportion of time spent expressing a prepotent response and engaging executive processes using a series of nonlinear (generalized logistic) growth models. As hypothesized, the average proportion of time children expressed prepotent responses decreased with age, and the average proportion of time engaged in executive processes increased with age. Individual differences in the developmental timing of changes in prepotent responses and executive process were correlated r = .35 such that the timing of decrease in proportion of time expressing prepotent responses was coupled with the timing of increase in proportion of time engaging executive processes.

Supplemental Material for Individual Differences in Timing of Susceptibility to Adverse Effects of Family Dysfunction

Supplemental Material for Individual Differences in Timing of Susceptibility to Adverse Effects of Family Dysfunction

A management-scale investigation of consistent individual differences in behaviour and trapping bias in sea lamprey (Petromyzon marinus)

The sea lamprey (Petromyzon marinus) is invasive in the Laurentian Great Lakes. Trapping in large rivers could suppress sea lamprey recruitment by removing migrating adults prior to spawning. Currently, the proportion of sea lamprey trapped (efficiency) is too low for control purposes, possibly because trapping is biased toward certain behavioural types. We tested if individual differences in time to enter a novel environment (risk-taking) and proportion of time moving (activity) under standardized laboratory conditions were correlated with time to encounter and enter a trap in the field. 638 sea lamprey were tagged, assessed for risk-taking and activity in sequential trials, and released in the river to be trapped. In the laboratory, individuals differed consistently in risk-taking and activity behaviours, and more active individuals entered a simulated trap sooner than less active individuals. In the field, however, the times to first trap encounter, and capture in a trap, were not correlated with risk-taking or activity. Our study provides a novel demonstration of how patterns from small-scale behavioural studies may not extend to management-scale applications.

Two-part mixed-effects location scale models.

Longitudinal time use data afford the opportunity to study within- and between-individual differences, but can present challenges in data analysis. Often the response set includes a large number of zeros representing those who did not engage in the target behavior. Coupled with this is a continuous measure of time use for those who did engage. The latter is strictly positive and skewed to the right if relatively few individuals engage in the behavior to a greater extent. Data analysis is further complicated for repeated measures, because within-individual responses are typically correlated, and some respondents may have missing data. This combination of zeros and positive responses is characteristic of a type of semicontinuous data in which the response is equal to a discrete value and is otherwise continuous. Two-part models have been successfully applied to cross-sectional time use data when the research goals distinguish between a respondent's likelihood to engage in a behavior and the time spent conditional on any time being spent, as these models allow different covariates to relate to each distinct aspect of a behavior. Two-part mixed-effects models extend two-part models for analysis of longitudinal semicontinuous data to simultaneously address longitudinal decisions to engage in a behavior and time spent conditional on any time spent. Heterogeneity between and within individuals can be studied in unique ways. This paper presents applications of these models to daily diary data to study individual differences in time spent relaxing or engaged in leisure activities for an adult sample.

On the One Hand or on the Other: Trade-Off in Timing Precision in Bimanual Musical Scale Playing.

Music performance requires simultaneously producing challenging movement sequences with the left and right hand. A key question in bimanual motor control research is whether bimanual movements are produced by combining unimanual controllers or through a dedicated bimanual controller. Here, 34 expert pianists performed musical scale playing movements with the left or right hand alone and with both hands simultaneously. We found that for the left hand, scale playing was more variable when playing with both hands simultaneously rather than with one hand at a time, but for the right hand, performance was identical. This indicates that when task constraints are high, musicians prioritize timing accuracy in the right hand at the cost of detriment of performance in the left hand. We also found that individual differences in timing substantially overlap between the unimanual and bimanual condition, suggesting control policies are similar but not identical when playing with two hands or one. In the bimanual condition, the left-hand keystrokes tended to occur before right-hand ones, and more so when the hands were further apart. Performance of the two hands was furthermore coupled so that they tended to be early and late together, especially in the beginning and end of each scale. This suggests that experts are able to achieve tightly coupled timing of scale playing movements between the hands. Taken together, these findings show evidence for partially overlapping and partially separate controllers for bimanual and unimanual movements in piano playing.

The Relationship Between a Balanced Time Perspective and Self-monitoring of Blood Glucose Among People With Type 1 Diabetes.

Self-monitoring of blood glucose helps people with type 1 diabetes to maintain glycemic control and reduce the risk of complications. However, adherence to blood glucose monitoring is often suboptimal. Like many health behaviors, self-monitoring of blood glucose involves exerting effort in the present to achieve future benefits. As such, the present research explored whether individual differences in time perspective-specifically, the extent to which people have a balanced time perspective-are associated with the frequency with which people with type 1 diabetes monitor their blood glucose and, thus, maintain glycemic control. Adults with type 1 diabetes completed measures of time perspective, feelings associated with monitoring, attitudes toward monitoring, and trait self-control. Objective data regarding the frequency with which participants monitored their blood glucose levels and their long-term glycemic control were extracted from their medical records. Hierarchical regression analyses and tests of indirect effects (N = 129) indicated that having a more balanced time perspective was associated with more frequent monitoring of blood glucose and, as a result, better glycemic control. Further analyses (N = 158) also indicated that there was an indirect relationship between balanced time perspective and monitoring of blood glucose via the feelings that participants associated with monitoring and their subsequent attitudes toward monitoring. These findings point to the importance and relevance of time perspective for understanding health-related behavior and may help to inform interventions designed to promote self-monitoring of blood glucose in people with type 1 diabetes.

Individual differences in timing of peak positive subjective responses to d-amphetamine: Relationship to pharmacokinetics and physiology.

Rate of delivery of psychostimulants has been associated with their positive euphoric effects and potential addiction liability. However, information on individual differences in onset of d-amphetamine's effects remains scarce. We examined individual differences in the time to peak subjective and physiological effects and the pharmacokinetics/pharmacodynamics of oral d-amphetamine. We considered two independent studies that used different dosing regimens where subjects completed the drug effects questionnaire at multiple time points post d-amphetamine. Based on the observation of distinct individual differences in time course of drug effects questionnaire "feel", "high", and "like" ratings (DEQH+L+F) in Study 1, subjects in both studies were categorized as early peak responders (peak within 60 minutes), late peak responders (peak > 60 minutes) or nonresponders; 20-25% of participants were categorized as early peak responders, 50-55% as late peak responders and 20-30% as nonresponders. Physiological (both studies) and plasma d-amphetamine (Study 1) were compared among these groups. Early peak responders exhibited an earlier rise in plasma d-amphetamine levels and more sustained elevation in heart rate compared to late peak responders. The present data illustrate the presence of significant individual differences in the temporal pattern of responses to oral d-amphetamine, which may contribute to heightened abuse potential.

Developmental variations in environmental influences including endocrine disruptors on pubertal timing and neuroendocrine control: Revision of human observations and mechanistic insight from rodents

Puberty presents remarkable individual differences in timing reaching over 5 years in humans. We put emphasis on the two edges of the age distribution of pubertal signs in humans and point to an extended distribution towards earliness for initial pubertal stages and towards lateness for final pubertal stages. Such distortion of distribution is a recent phenomenon. This suggests changing environmental influences including the possible role of nutrition, stress and endocrine disruptors. Our ability to assess neuroendocrine effects and mechanisms is very limited in humans. Using the rodent as a model, we examine the impact of environmental factors on the individual variations in pubertal timing and the possible underlying mechanisms. The capacity of environmental factors to shape functioning of the neuroendocrine system is thought to be maximal during fetal and early postnatal life and possibly less important when approaching the time of onset of puberty.

Mean Difference of Age at Menarche and Body Mass Index among Government and Private High-School Students of Mekelle City, Northern Ethiopia

Background: The mean age at menarche varies from one setting to another. Individual differences in timing of menarche are associated with age differences in the onset of sexual activity and first pregnancy. The study was conducted to determine the mean difference of age at menarche and body mass index (BMI) among government and private high-school students of Mekelle city. Method: A cross sectional study design was conducted in selected 6 governmental and private schools of Mekelle city. A total of 290 study subjects were interviewed. Systematic random sampling method was used to select study subjects. An independent sample t-test was done for two independent groups to compare age at menarche among governmental and private school girls in relation to various variables. One-way ANOVA and Pearson’s correlation analysis was conducted on the combined analysis for the relationship between age at menarche and independent variables. Result: The mean age at menarche was 14.24 year ±1.42 SD. The mean age at menarche was one year younger for private school girls compared with government school girls (t=6.2, P<0.001). Time spending sitting in a day (r= −0.25, p<0.001) duration of sleeping (r= -0.13, p=0.03), living in their own house (t= -2.42, P<0.05) were negatively correlated with age at menarche. There was significant difference of age at menarche among the participants maternal education (F=6.0, P<0.001), Father’s education (F=8.45, P<0.001), and father’s job (F=9.55, P<0.001). The mean BMI of the participants was 20.22 ± 2.66 SD. More than quarters of the participants were underweight (26.3%). Conclusion: The mean age of menarche found in this study was higher than the report from other African countries. The mean age at menarche was statically different among the government and private school girls. Time spending sitting, duration of sleeping, living in their own house were negatively correlated with age at menarche.

The Vigilance Decrement in Executive Function Is Attenuated When Individual Chronotypes Perform at Their Optimal Time of Day

Time of day modulates our cognitive functions, especially those related to executive control, such as the ability to inhibit inappropriate responses. However, the impact of individual differences in time of day preferences (i.e. morning vs. evening chronotype) had not been considered by most studies. It was also unclear whether the vigilance decrement (impaired performance with time on task) depends on both time of day and chronotype. In this study, morning-type and evening-type participants performed a task measuring vigilance and response inhibition (the Sustained Attention to Response Task, SART) in morning and evening sessions. The results showed that the vigilance decrement in inhibitory performance was accentuated at non-optimal as compared to optimal times of day. In the morning-type group, inhibition performance decreased linearly with time on task only in the evening session, whereas in the morning session it remained more accurate and stable over time. In contrast, inhibition performance in the evening-type group showed a linear vigilance decrement in the morning session, whereas in the evening session the vigilance decrement was attenuated, following a quadratic trend. Our findings imply that the negative effects of time on task in executive control can be prevented by scheduling cognitive tasks at the optimal time of day according to specific circadian profiles of individuals. Therefore, time of day and chronotype influences should be considered in research and clinical studies as well as real-word situations demanding executive control for response inhibition.

Controlling Individuals’ Time Spent on Task in Speeded Performance Measures

The speed-ability trade-off becomes a measurement problem if there is between-subject variation in the speed-ability compromise, as this may affect the comparability of ability estimates. To control individual speed differences, the response-signal (RS) paradigm was applied requiring an immediate response as soon as an acoustic signal is presented. A figural discrimination task and a word recognition task were completed both in an untimed condition allowing individual differences in time spent on task and in several timed conditions where the time available for item completion was limited using the RS paradigm. Thus, speed was manipulated by varying the available time between stimulus-onset and RS. A total of N = 205 high school students participated in the study. Results showed that across timed conditions with decreasing time on task, the ability level and ability variance decreased substantially. Ability correlations between timed conditions were high, whereas correlations between untimed and timed conditions were low. This finding suggested that ability differences being inconsistent to those found in the timed condition are due to individual differences in time on task in the untimed condition. To eliminate these differences, two ways were considered. First, untimed responses were recoded using two-tailed posterior time limits. As expected, correlations between timed and untimed conditions were increased. Second, the log-transformed item response times were included in the item response model, which led to even higher correlations between timed and untimed conditions. Validity and generalizability of the proposed testing procedure are discussed.

How supervisors' reminders relate to subordinates' absorption and creativity

PurposeThis study aims to examine supervisors' temporal reminders and subordinates' pacing style as they relate to employees' absorption in work tasks, and subsequently creativity.Design/methodology/approachThe study involved a weekly diary study among 32 employees of an IT‐development department of a large multinational. An initial questionnaire measured employees' pacing style and their perceptions of supervisors' temporal reminders, after which participants completed a weekly survey for four consecutive weeks to report on their levels of task absorption and creativity.FindingsWhereas supervisors' temporal reminders related positively with task absorption for individuals who scored high rather than low on the deadline action pacing style, they related negatively to task absorption for those high rather than low on the steady action and the U‐shaped action pacing styles. Moreover, task absorption fluctuated consistently with individual creativity.Research limitations/implicationsThe way individuals allocate efforts over time is not only related to the resources they invest in activities but also to their creativity.Practical implicationsThe findings suggest that creativity requires that employees find the time and space to fully immerse in their work. Supervisors can facilitate this process by customizing their leadership practices to individual differences in time use.Social implicationsIn an increasingly time‐pressured corporate society, an effective management of temporal strategies is important to ensure sustained employee well‐being as well as the quality of products in terms of creative solutions.Originality/valueThis study is the first to show that supervisors' temporal reminders relate positively to task absorption, and subsequent creativity levels, but only for specific pacing styles.

Individual Differences in Motor Timing and Its Relation to Cognitive and Fine Motor Skills

The present study investigated the relationship between individual differences in timing movements at the level of milliseconds and performance on selected cognitive and fine motor skills. For this purpose, young adult participants (N = 100) performed a repetitive movement task paced by an auditory metronome at different rates. Psychometric measures included the digit-span and symbol search subtasks from the Wechsler battery as well as the Raven SPM. Fine motor skills were assessed with the Purdue Pegboard test. Motor timing performance was significantly related (mean r = .3) to cognitive measures, and explained both unique and shared variance with information-processing speed of Raven's scores. No significant relations were found between motor timing measures and fine motor skills. These results show that individual differences in cognitive and motor timing performance is to some extent dependent upon shared processing not associated with individual differences in manual dexterity.

Individual differences in timing of discrete and continuous movements: a dimensional approach

This study investigated aspects of individual differences in timing of continuous and discontinuous movements to different pacing signals (auditory or visual), pacing intervals (500, 650, 800, 950 ms), and across effectors (dominant versus non-dominant hand). Correlation and principal component analysis demonstrated that a single statistical dimension accounted for up to 60% of the explained variance in discontinuous tasks and 25% of the variance in continuous tasks, when applied to performance obtained from tasks conducted with different effectors and at different pacing rates. Correlation analysis of factor scores representing effector and rate independent task performances showed that timing of discrete or continuous movements can be associated with modality independent mechanisms. Timing variability from discrete and continuous trials was not significantly correlated. This study goes beyond previous correlational work on individual differences in discrete and continuous movements, demonstrating that individual differences in discrete (event-based) or continuous (emergent) motor timing tasks can be modeled as distinctive statistical components with dissimilar capability to capture effector, rate, and modality independent variance.

INDIVIDUAL DIFFERENCES IN IMPULSIVE CHOICE AND TIMING IN RATS

Individual differences in impulsive choice behavior have been linked to a variety of behavioral problems including substance abuse, smoking, gambling, and poor financial decision-making. Given the potential importance of individual differences in impulsive choice as a predictor of behavioral problems, the present study sought to measure the extent of individual differences in a normal sample of hooded Lister rats. Three experiments utilized variations of a delay discounting task to measure the degree of variation in impulsive choice behavior across individual rats. The individual differences accounted for 22-55% of the variance in choice behavior across the three experiments. In Experiments 2 and 3, the individual differences were still apparent when behavior was measured across multiple choice points. Large individual differences in the rate of responding, and modest individual differences in timing of responding were also observed during occasional peak trials. The individual differences in timing and rate, however, did not correlate consistently with individual differences in choice behavior. This suggests that a variety of factors may affect choice behavior, response rate, and response timing.

Neural dynamics of object-based multifocal visual spatial attention and priming: Object cueing, useful-field-of-view, and crowding

How are spatial and object attention coordinated to achieve rapid object learning and recognition during eye movement search? How do prefrontal priming and parietal spatial mechanisms interact to determine the reaction time costs of intra-object attention shifts, inter-object attention shifts, and shifts between visible objects and covertly cued locations? What factors underlie individual differences in the timing and frequency of such attentional shifts? How do transient and sustained spatial attentional mechanisms work and interact? How can volition, mediated via the basal ganglia, influence the span of spatial attention? A neural model is developed of how spatial attention in the where cortical stream coordinates view-invariant object category learning in the what cortical stream under free viewing conditions. The model simulates psychological data about the dynamics of covert attention priming and switching requiring multifocal attention without eye movements. The model predicts how “attentional shrouds” are formed when surface representations in cortical area V4 resonate with spatial attention in posterior parietal cortex (PPC) and prefrontal cortex (PFC), while shrouds compete among themselves for dominance. Winning shrouds support invariant object category learning, and active surface-shroud resonances support conscious surface perception and recognition. Attentive competition between multiple objects and cues simulates reaction-time data from the two-object cueing paradigm. The relative strength of sustained surface-driven and fast-transient motion-driven spatial attention controls individual differences in reaction time for invalid cues. Competition between surface-driven attentional shrouds controls individual differences in detection rate of peripheral targets in useful-field-of-view tasks. The model proposes how the strength of competition can be mediated, though learning or momentary changes in volition, by the basal ganglia. A new explanation of crowding shows how the cortical magnification factor, among other variables, can cause multiple object surfaces to share a single surface-shroud resonance, thereby preventing recognition of the individual objects.

Individual differences in boys' and girls' timing and tempo of puberty: Modeling development with nonlinear growth models.

Pubertal development is a nonlinear process progressing from prepubescent beginnings through biological, physical, and psychological changes to full sexual maturity. To tether theoretical concepts of puberty with sophisticated longitudinal, analytical models capable of articulating pubertal development more accurately, we used nonlinear mixed-effects models to describe both the timing and tempo of pubertal development in the sample of 364 White boys and 373 White girls measured across 6 years as part of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development. Individual differences in timing and tempo were extracted with models of logistic growth. Differential relations emerged for how boys' and girls' timing and tempo of development were related to physical characteristics (body mass index, height, and weight) and psychological outcomes (internalizing problems, externalizing problems, and risky sexual behavior). Timing and tempo are associated in boys but not girls. Pubertal timing and tempo are particularly important for predicting psychological outcomes in girls but only sparsely related to boys' psychological outcomes. Results highlight the importance of considering the nonlinear nature of puberty and expand the repertoire of possibilities for examining important aspects of how and when pubertal processes contribute to development.

Genetic Determinants of Time Perception Mediated by the Serotonergic System

BackgroundThe present study investigates neurobiological underpinnings of individual differences in time perception.MethodologyForty-four right-handed Russian Caucasian males (18–35 years old) participated in the experiment. The polymorphism of the genes related to the activity of serotonin (5-HT) and dopamine (DA)-systems (such as 5-HTT, 5HT2a, MAOA, DAT, DRD2, COMT) was determined upon the basis of DNA analysis according to a standard procedure. Time perception in the supra-second range (mean duration 4.8 s) was studied, using the duration discrimination task and parametric fitting of psychometric functions, resulting in individual determination of the point of subjective equality (PSE). Assuming the ‘dual klepsydra model’ of internal duration representation, the PSE values were transformed into equivalent values of the parameter (kappa), which is a measure of the ‘loss rate’ of the duration representation. An association between time representation parameters (PSE and , respectively) and 5-HT-related genes was found, but not with DA-related genes. Higher ‘loss rate’ () of the cumulative duration representation were found for the carriers of genotypes characterized by higher 5-HT transmission, i.e., 1) lower 5-HT reuptake, known for the 5-HTTLPR SS polymorphism compared with LL, 2) lower 5-HT degradation, described for the ‘low expression’ variant of MAOA VNTR gene compared with ‘high expression’ variant, and 3) higher 5-HT2a receptor density, proposed for the TT polymorphism of 5-HT2a T102C gene compared with CC.ConclusionConvergent findings of the present study and previous psychopharmacological studies suggest an action path from 5-HT-activity-related genes, via activity of 5-HT in the brain, to time perception. An involvement of the DA-system in the encoding of durations in the supra-second range is questioned.

Constraints on the Timing of Infant Cognitive Change: Domain-Specific or Domain-General?

Most studies of infant cognition focus on group data from single domains. Yet, without the multidomain testing of the same infants longitudinally, such data cannot be used to evaluate whether the timing of cognitive change occurs in a domain-general or a domain-specific way. We present the results of a longitudinal study pooling data from three European laboratories set up identically. Over 100 healthy, monolingual infants each underwent multi-domain testing at 6 and again at 10 months in six experimental tasks (speech processing, face processing, and action/event processing), as well as a videotaped 3-minute recording of mother/infant dyads in a play session with an identical set of toys. Previous research examined the effects of maternal sensitivity only on general intelligence measures, but our approach is novel in that it assessed dyadic effects on specific cognitive domains, attempting to pinpoint in finer detail the effects of mother-infant dyadic interaction on the timing of cognitive change. Our findings highlight the importance of a multi-domain approach, in that unlike the assumptions drawn from cross-sectional data, our longitudinal study yielded different developmental timing across domains within the same infants. Our results also highlight a crucial difference: at the group level 6- and 10-month-olds display the expected effects found in previous research, but when re-analysed according to mother-child interaction ratings, the quality of dyadic interaction style turned out to subtly foster or delay development in domainspecific and age-specific ways, contributing to the range of individual differences in timing that we observe in cognitive development over the first year of life.