Introduction
Executive functions (EFs) are defined as cognitive processes related to the prefrontal cortex (PFC) that allow an individual to remain focused on a task (Carlson et al., Reference Carlson, Faja, Beck, Griffin, McCardle and Freund2016; Diamond, Reference Diamond, Bialystok and Craik2006, Reference Diamond2013; Hughes, Reference Hughes and Hopkins2005; Jacques & Marcovitch, Reference Jacques, Marcovitch, Overton and Lerner2010; Miller & Cohen, Reference Miller and Cohen2001). EFs develop during childhood and into early adulthood (Casey et al., Reference Casey, Galvan and Hare2005; Diamond, Reference Diamond, Stuss and Knight2002; Huttenlocher, Reference Huttenlocher1979, Reference Huttenlocher1990; Sowell et al., Reference Sowell, Thompson, Holmes, Jernigan and Toga1999), with inhibitory control (IC) and working memory (WM) emerging during the first year of life (Baird et al., Reference Baird, Kagan, Gaudette, Walz, Hershlag and Boas2002; Diamond et al., Reference Diamond, Barnett, Thomas and Munro2007; Diamond, Reference Diamond, Stuss and Knight2002; Garon et al., Reference Garon, Bryson and Smith2008; Wolfe & Belle, Reference Wolfe and Bell2007) and cognitive flexibility developing between the ages of 3 and 4 (Moriguchi & Hiraki, Reference Moriguchi and Hiraki2011). There is widespread agreement that the two main early components of IC and WM develop first (Diamond, Reference Diamond2013; Lehto et al., Reference Lehto., Juujarvi, Kooistra and Pulkkinen2003, Logue & Gould, Reference Logue and Gould2014; Miyake et al., Reference Miyake, Friedgaman, Emerson, Wittki, Howerter and Wager2000), and both support later-emerging EF and cognitive processes (Collins & Koechlin, Reference Collins and Koechlin2012; Lunt et al., Reference Lunt, Bramham, Morris, Bullock, Selway, Xenitidis and David2012). The EFs of IC and WM are independent, but both have a common purpose of allocating attention and control over behavior to meet a goal (Friedman & Miyake, Reference Friedman and Miyake2017; Miyake & Friedman, Reference Miyake and Friedman2012; Miyake et al., Reference Miyake, Friedgaman, Emerson, Wittki, Howerter and Wager2000). A plethora of developmental research indicates that EFs are important to several elements of positive cognitive and social development including theory of mind, pretend play, emotion regulation, moral conduct, and school readiness (Blair & Razza, Reference Blair and Razza2007; Carlson et al., Reference Carlson, Mandell and Williams2004; Carlson & Wang, Reference Carlson and Wang2007; Carlson & White, Reference Carlson, White and Taylor2013; Hughes et al., Reference Hughes, Foley, Browne, McHarg and Devine2023; Liu et al., Reference Liu, Chung and Fung2019; Mann et al., Reference Mann, Hund, Hesson-McInnis and Roman2017). Deficits in EFs are also a risk factor for some aspects of child psychopathology as well as poor social and academic adjustment (Casey et al., Reference Casey, Tottenham and Fossella2002; Hughes & Ensor, Reference Hughes and Ensor2011; Kim-Spoon et al., Reference Kim-Spoon, Deater-Deckard, Calkins, King-Casas and Bell2019).
Inhibitory control (IC)
Although IC is considered an EF, there are both cognitive and socio-emotional aspects of IC reflected by theory and research from EF and temperament perspectives, respectively. The EF perspective defines IC as the ability to control one’s thinking, emotion, and behavior by focusing one’s attention to produce goal-oriented behavior (Diamond, Reference Diamond2013). Individuals with low IC tend to behave more impulsively than those with typically developing IC (Diamond, Reference Diamond, Zelazo and Sera2014). IC emerges developmentally in the first few years of life with corresponding evidence of individual differences in IC task performance (Petersen et al., Reference Petersen, Hoyniak, McQuillian, Bates and Staples2016). This rapid early development is attributed to neurobiological and PFC development in early childhood (Draperi et al., Reference Draperi, Aïte, Cassotti, Le Stanc, Houdé and Borst2022; Simpson & Carroll, Reference Simpson and Carroll2019; Zelazo et al., 2016; Zelazo & Müller, Reference Zelazo, Müller and Goswami2010). EF researchers use tasks such as Stroop (McLeod, Reference McLeod1991), go/no-go (Cragg & Nation, Reference Cragg and Nation2008), and Flanker (Eriksen & Eriksen, Reference Eriksen and Eriksen1974, Mullane et al., Reference Mullane, Corkum, Klein and McLaughlin2009) to assess IC in childhood, reflecting the ability to utilize executive control.
Working memory (WM)
Working memory (WM) is defined as a central cognitive system composed of capacity and speed of processing components that develops from infancy through adolescence (Spencer, Reference Spencer2020), that retains perceptually absent information in mind (short-term storage) and employs it in some way (Baddeley & Hitch, Reference Baddeley and Hitch1994; Diamond, Reference Diamond2013; Smith & Jonides, Reference Smith and Jonides1999). Models of children from preschool to early elementary school indicate that the structure of WM includes verbal, visual, special-simultaneous, and spatial-sequential components (Carretti et al., Reference Carretti, Giofrè, Toffalini, Cornoldi, Pastore and Lanfranchi2022). WM is essential for learning new concepts, following directions, remembering past events to make plans, understanding written and oral language, and the mental computation required for mathematics (Diamond, Reference Diamond2013). WM research typically involves child-level memory tasks and several studies have shown WM to be related to essential cognitive abilities for school transition such as reading (Baddeley, Reference Baddeley1992; Daneman & Carpenter, Reference Daneman and Carpenter1980), writing (McCutchen, Reference McCutchen1996; Swanson & Berninger, Reference Swanson and Berninger1996), and arithmetic (De Smedt et al., Reference De Smedt, Janssen, Bouwens, Verschaffel, Boets and Ghesquière2009; Destefano & Lefevre, Reference DeStefano and LeFevre2004; Gathercole et al., Reference Gathercole, Pickering, Knight and Stegmann2004). WM also predicts math and reading competence longitudinally into young adulthood (Alloway & Alloway, Reference Alloway and Alloway2010; Bull & Scerif, Reference Bull and Scerif2001; Dumontheil & Klingberg, Reference Dumontheil and Klingberg2012; Gathercole et al., Reference Gathercole, Pickering, Knight and Stegmann2004). WM and IC are considered critical components of one another, with each providing support for the development and employment of the other (Diamond, Reference Diamond2013).
Incorporating the temperament perspective on inhibitory control
The EF perspective on IC is predominantly employed in cognitive neuroscience theory and research and has influenced the broader child development and education fields. The other primary theoretical and empirical approach to IC is the temperament perspective. There are many similarities between the EF and temperament approaches to IC, but several noteworthy distinctions. Temperament is traditionally defined as early emerging, individual differences in emotional, behavioral, and in more recent decades, cognitive development that are fairly stable, biologically based traits (Rothbart & Bates, Reference Rothbart, Bates, Damon, Lerner and Eisenberg2006; Zhou et al., Reference Zhou, Chen and Main2012). Temperament theory and research has traditionally focused on socioemotional development, highlighting strong associations between temperament traits or dimensions, and psychopathology in childhood and adulthood, as well as adult personality (Caspi et al., Reference Caspi, Roberts and Shiner2005; Goldsmith et al., Reference Goldsmith, Lemery, Essex and DiLalla2004). However, beginning with Mary Rothbart’s influential theory, cognitive processes and development have been incorporated into conceptions of temperament, what she describes as executive attention (Rothbart & Bates, Reference Rothbart, Bates, Damon, Lerner and Eisenberg2006). According to Rothbart, the temperament dimension of IC (as opposed to the EF) is a major element of the broader temperament factor or domain of effortful control (Rothbart et al., Reference Rothbart, Ahadi and Hershey1994; Rothbart & Bates, Reference Rothbart, Bates, Damon, Lerner and Eisenberg2006). She further defines effortful control (EC) as “the efficiency of executive attention, including the ability to inhibit a dominant response, to activate a subdominant response, to plan, and to detect errors” (Rothbart & Bates, Reference Rothbart, Bates, Damon, Lerner and Eisenberg2006, p. 129). The temperament conception of IC is this inhibition of impulsive or pre-potent behavior, typically under some form of expectation or instruction (Kochanska et al., Reference Kochanska, Murray, Jacques, Koenig and Vandegeest1996; Rothbart, Reference Rothbart, Kohnstamm, Bates and Rothbart1989). Basic examples include refraining from eating a snack for an extended period, like Mischel’s marshmallow task (Metcalfe & Mischel, Reference Metcalfe and Mischel1999), and being successful on similar delay tasks often used in temperament research on IC.
Both EF and temperament researchers study early-emerging IC because appropriate levels of IC are linked to academic achievement and positive social-emotional competence (Espy et al., Reference Espy, McDiarmid, Cwik, Stalets, Hamby and Senn2004; Nigg et al., Reference Nigg, Wong, Martel, Jester, Puttler, Glass, Adams, Fitzgerald and Zucker2006; Raaijmakers et al., Reference Raaijmakers, Smidts, Sergeant, Maassen, Posthumus, Van Engeland and Matthys2008; St. Clair-Thompson & Gathercole, Reference St. Clair-Thompson and Gathercole2006), while low levels of IC are associated with externalizing behavior problems and attention deficit hyperactivity disorder (ADHD; Eisenberg et al., Reference Eisenberg, Cumberland, Spinrad, Fabes, Shepard, Reiser, Murphy, Losoya and Guthrie2001, Reference Eisenberg, Spinrad, Fabes, Reiser, Cumberland, Shepard, Valiente, Losoya, Guthrie and Thompson2004; Gagne et al., Reference Gagne, Saudino and Asherson2011; Goos et al., Reference Goos, Crosbie, Payne and Schachar2009). Early childhood behavioral maladjustment is related to poor health and education outcomes (Denham et al., Reference Denham, Workman, Cole, Weissbrod, Kendziora and Zahn-Waxler2000; Gagne, Reference Gagne2017; Saudino et al., Reference Saudino, Carter, Purper-Ouakil and Gorwood2008), and “inhibitory control seems to be the executive function most predictive of long-term outcomes” (Diamond, Reference Diamond, Zelazo and Sera2014). In a longitudinal study, Moffitt et al. (Reference Moffitt, Arseneault, Belsky, Dickson, Hancox, Harrington, Houts, Poulton, Roberts, Ross, Sears, Thomson and Caspi2011) found that children with higher IC participated in fewer risky behaviors like smoking, dropping out of school, and experienced fewer unplanned pregnancies as adolescents. As adults, they were healthier, had higher incomes and better jobs, saved more money for the future, and had fewer experiences with the criminal justice system than children with lower IC.
Although both temperament and EF approaches to IC assessment are used in investigations that follow each perspective, rarely are both preschool EF and temperament IC assessments employed in the same study to predict elementary school outcomes. A multi-method IC assessment approach incorporating both perspectives provides researchers with much clearer knowledge of how the EF and temperament aspects of IC predict academic and behavioral outcomes. In addition to EF and temperament tasks, many preschool IC studies also utilize parent rating scales. Parent ratings are typically reliable and valid, but can be prone to rater bias, including contrast effects in family studies (Saudino, Reference Saudino2003), and parent ratings of IC often evince a pattern of higher rater covariance with parent-rated behavior problems (Gagne et al., Reference Gagne, Chang, Fang, Spann and Kwok2018). Therefore, a multi-method assessment approach including parent ratings and in-person lab-based EF, and temperament tasks affords investigators both a comprehensive assessment methodology and the ability to account for shared method variance (Podsakoff et al., Reference Podsakoff, MacKenzie, Lee and Podsakoff2003).
Relevant parent and family factors
Aside from this multi-method approach, accounting for parent and family factors is another important consideration. Although many investigations of IC and EF focus primarily on the child, family study designs that include parent and sibling data allow investigators to incorporate data on family members that could be relevant to these aspects of child development. Parent personality traits (e.g., neuroticism), parenting style, emotional and affective style, family conflict, substance use, and parent depression and anxiety are often studied. Therefore, employing a family study approach incorporating both parent and child data can provide more complex analyses and interpretations of how preschool IC and WM predict elementary school outcomes. For example, maternal depression symptoms are common and may be chronic (Field, Reference Field2011), up to 24% of 17-month-olds in one study were exposed to these symptoms (McLennan et al., Reference McLennan, Kotelchuck and Cho2001), and exposure can confer a higher risk for negative child outcomes (Hughes et al., Reference Hughes, Roman, Hart and Ensor2013). Previous EF research has shown that maternal depression symptoms predict child EF longitudinally (Hughes et al., Reference Hughes, Roman, Hart and Ensor2013), and maternal anxiety during pregnancy was also associated with lower EF in 6- to 9-year-olds (Buss et al., Reference Buss, Davis, Hobel and Sandman2011). Postnatal maternal anxiety and depression have been linked to lower child attentional control, prenatal anxiety with impaired WM, and postnatal anxiety is related to math and language failure (Pearson et al., Reference Pearson, Bornstein, Cordero, Scerif, Mahedy, Evans, Abioye and Stein2016). With regards to behavioral maladjustment in children, maternal depression is linked to both externalizing (Ashman et al., Reference Ashman, Dawson and Panagiotides2008; Gagne et al., Reference Gagne, Barker, Chang, Nwadinobi and Kwok2021; Spann & Gagne, Reference Spann and Gagne2016) and internalizing problems (Gartstein et al., Reference Gartstein, Bridgett, Rothbart, Robertson, Iddins, Ramsay and Schlect2010; Murray et al., Reference Murray, Arteche, Fearon, Halligan, Goodyer and Cooper2011). Interestingly, EF at age 3 mediated links between maternal depression and externalizing and internalizing problems at age 6, indicating that EF interventions could have a beneficial effect on child adjustment outcomes (Roman et al., Reference Roman, Ensor and Hughes2016). Therefore, maternal depression and anxiety during the preschool years may have potentially negative effects on EF, temperament, and adjustment.
The current study
The primary goal of the current study was to examine IC (both EF and temperament measures) and WM in preschool as predictors of social and behavioral adjustment outcomes in elementary school. In addition, we examined maternal depression and anxiety and child behavior problems at preschool as predictors of the same elementary school outcomes. Based on our multi-method approach, we expect that both our EF and temperament measures of IC in preschool will predict the elementary school outcomes under study. However, there may be some variability on what outcomes each type of IC will predict and the strength of relationships. We also expect that maternal depression and anxiety, and preschool WM and behavioral problems will be linked to these important elementary school outcomes. In general, higher levels of preschool IC and WM, and low levels of maternal anxiety and depression, and preschool behavior problems will be associated with positive outcomes. Preschool age and gender will also be modeled in our analyses.
Methods
Participants
Ninety-nine families with two typically developing siblings (N = 198) aged 2.5 – 5.5 years (M = 3.88, SD = 1.04) participated in the preschool phase of the study. The primary caregivers (mostly mothers) rated the siblings’ temperament and behavior problems, as well as several family and parent variables. The sample is composed of 102 male children (mean age = 3.79, SD = 0.99) and 96 females (mean age = 3.97, SD = 1.08), including 57 full sibling pairs, 10 identical twin pairs, and 32 fraternal twin pairs. The sample was mostly White (84% of children, 88% of mothers, and 87% of fathers), followed by Hispanic or Latino (13% of children; 7% of mothers; and 8% of fathers), multiracial (11% children; 5% mothers; and 4% fathers), and African American (4% children; 4% mothers; and 7% fathers) families. Less than 3% were reported as Asian American, Pacific Islander, and other races. Average annual household income for participants was $70,000 (range = $20,000 – $200,000+). Average years of education were 15.82 for mothers and 15.12 for fathers (range = 8 – 22 years).
Out of the 126 families who finished all online surveys, 99 participated in the preschool laboratory visit. There were no significant demographic differences between the families who participated in the laboratory visit and those who only completed the online surveys, except the average child age was lower for those families who didn’t take part in the laboratory visit because many parents completed the online surveys when their children were not in the eligible age range for this study. When the children in the original sample reached elementary school age, the parents were invited to participate in a follow-up survey online. The follow-up sample at elementary school was composed of 128 of the original children aged 5 – 11 years (mean = 7.5, SD = 1.26) based on 70 families out of the original 99. The primary caretaker was asked to complete online questionnaires for this elementary school phase of the study. All information was de-identified to ensure anonymity and security. There were no significant differences in race/ethnicity and SES between families who did not participate in the elementary school phase and those who did.
Procedures
Dallas-Fort Worth metroplex families were recruited using flyers on a suburban university campus, pediatricians’ offices, daycare centers, and postings on the Internet and study website. All participants were pre-screened for eligibility based on child age and developmental disorder status before being invited to begin the three sets of online surveys on SurveyMonkey. While the children took part in the lab visit, parents completed additional questionnaires. Study participants received a $25 gift card upon completion of the online surveys and an additional $50 gift card was remunerated to those who completed the lab visit. The elementary school follow-up study was administered using online surveys on SurveyMonkey. Surveys based on family variables, parent variables, child one, and child two were presented in four separate sections. Participants received a $50 email gift card as compensation upon completion of all surveys. Elementary school data were used in analyses after accurate dates of birth were confirmed for each child. The university Institutional Review Board reviewed and approved all research procedures for this study.
Measures
Preschool IC parent-rating
The IC subscale of the Toddler Behavior Assessment Questionnaire-Revised (TBAQ-R; Goldsmith, Reference Goldsmith1996) was used as the parent-report measure of IC. This subscale reflects parent judgments of their child’s IC with a high score indicating high IC. The TBAQ-R is composed of 120 items, with 13 items comprising the IC subscale. TBAQ-R items assess child temperament traits by asking parents about the frequency of child behaviors in specific situations in the past month. TBAQ-R items are composed of a 7-point Likert scale with 1 being “never” and 7 being “always”, with an “N/A” option. The TBAQ-R IC subscale used in our sample had an internal consistency reliability of 0.93, consistent with published findings (Goldsmith, Reference Goldsmith1996).
Preschool IC-laboratory temperament assessment battery (Lab-TAB)
A lab-based standardized assessment battery was also used to measure child IC using episodes from Lab-TAB (Goldsmith et al., Reference Goldsmith, Reilly, Lemery, Longley and Prescott1995). “Snack delay” and “gift” episodes from the preschool version of the Lab-TAB were employed. Data coders were trained to a 90% agreement with the master coders before coding independently. In addition, 20% of the sample was double coded with agreement exceeding 85%. In the “snack delay” task the child is given a snack (usually M&M’s or goldfish) and asked to wait for a bell to be rung before eating the snack. One snack at a time was placed under a clear plastic cup on a paper plate and the experimenter rings a bell when it was permissible to eat the snack. This task was repeated for six trials with intervals of 20, 30, 0, 40, 10, and 60 s. During the “gift” task a small, wrapped present is presented to the child and the experimenter requests that they wait before they open the gift. The child was then ignored by the researcher (the child was left to believe that the researcher is working on paperwork during the task) for 2 mins before the experimenter allows them to open it.
Preschool post-visit observer temperament rating
All experimenters completed global post-visit ratings of child temperament immediately after the lab visit. The scales for these ratings were based on 23 items estimating different global aspects of temperament on a 5-point scale where 1 served as absence of a characteristic (e.g., frustration, energy, or impulsivity) and 5 served as a high level of a characteristic. Previous multi-method investigations of temperament used similar ratings (e.g., Gagne et al., Reference Gagne, Saudino and Asherson2011) to serve as convergent validity for Lab-TAB and questionnaire measures. The attention to tasks, hyperactivity, and impulsivity scores were selected to assess child IC (internal consistency = 0.82).
Preschool stroop task
Three different Stroop Tasks were used to assess preschool IC based on the EF approach. Children were required to inhibit automatic impulses and to answer questions during these tasks. The tasks were assigned based on the child’s age with all three sharing a control condition, requiring no IC involvement. Following the control condition, the test phase occurred when the child was expected to inhibit the pre-potent reaction under instruction. Children 2.5 – 3.5 years of age performed the baby Stroop Task (Hughes and Ensor, Reference Hughes and Ensor2005), where the child would be shown a small “;baby”; cup and a regular-sized “mommy” cup. The control phase asked the child to point to either cup to make sure they understand the difference. Then, the experimenter told the child they were going to play an “opposite game”, in which the child needs to say “baby cup” when they were shown the “mommy cup” and vice versa. The two cups were presented to the child in a pseudorandom order, one at a time. Children 3.5 – 4.5 years of age played a hand game (Hughes, Reference Hughes1998). In the control phase, the child was asked to imitate the experimenter’s displaying a fist and then a pointing finger. Then, the experimenter asked the child to do the opposite action by displaying a fist if the experimenter showed a pointing finger and displaying a pointing finger if the experimenter made a fist. The reported Cronbach’s alpha for this task was 0.88, which indicates good internal consistency. Children 4.5 – 5.5 years of age performed the day-night task, whereby the child was requested to say “day” when a night card (with a moon and stars) was presented and to say “night” when a day card (with the sun) was presented. This procedure was repeated for 12 trials, and the number of correct was recorded. The internal reliability for this task ranged from 0.79 to 0.93 in a previous sample (Thorell & Wåhlstedt, Reference Thorell and Wåhlstedt2006), and the Cronbach’s alpha for our task was 0.96, indicating strong internal reliability. The combination of these three types of Stroop tasks has been used in previous published articles (Hughes & Ensor, Reference Hughes and Ensor2005, Reference Hughes and Ensor2011).
Preschool working memory
Working memory was assessed with the Spin the Pots task (Hughes and Ensor, Reference Hughes and Ensor2005). An array of visually distinct boxes was displayed on a Lazy Susan tray. The child was asked to assist in setting up the task by placing stickers inside the boxes. The number of the visual boxes employed was based on child age, with children 2.5 – 3.5 years old using 8 boxes, children 3.5 – 4.5 years old using 10 boxes, and children 4.5 – 5.5 years old using 12 boxes. During the task, the child was told that they didn’t have enough stickers for each box so two of the boxes would be empty. After setting up the boxes, the experimenter covered the Lazy Susan with a cloth and rotated the tray. The child was then asked to choose a box that had a sticker inside it. Once the child selected a box, the remaining boxes were covered again ready for the next spin trial. This procedure continued until all the stickers were found or until all the boxes had been chosen. WM scores were calculated as a proportion of the number of stickers accurately selected vs. the total number of spins, ranging from 0 to 1. Higher scores represent higher WM. Test-retest reliability on this task was significant in a previous sample (r = .59, p = .002; Lalonde & Holt, Reference Lalonde and Holt2014). The Cronbach’s alpha in our sample was 0.75, indicating good internal reliability.
Preschool behavior problems
The Child Behavior Checklist (CBCL; Achenbach & Rescorla, Reference Achenbach and Rescorla2000) was employed to measure externalizing behavior problems. The CBCL is considered a “gold standard” 100-item questionnaire that assesses children’s social/emotional functioning and behavior problems. Parents rated their children on 24 items that reflect externalizing behaviors that occurred in the past two months on a scale from 0 (“not true”) to 2 (“very true or often true”). Subscale total scores were calculated using summations of raw parental responses to items on each subscale based on the CBCL manual. Total scores were z-transformed prior to analyses with lower scores representing lower levels of behavior problems. The Cronbach’s alpha for the externalizing behavior problems subscale was 0.89, which is consistent with published internal consistencies (0.76 for narrow subscales and .92 for broad constructs; Achenbach & Edelbrock, Reference Achenbach, Edelbrock, Ollendick and Hersen1983).
Maternal depressive symptoms at preschool
The Center for Epidemiologic Studies Depression Scale (CES-D; Radloff, Reference Radloff1977) was used to measure depressive symptoms of mothers. Mothers were asked to complete the scale by indicating the frequency of their feelings during the past week. The CES-D includes 20 items rated on a 4-point Likert scale from 0 (“rarely or none of the time/less than 1 day”) to 3 (“most or all of the time/5 – 7 days”). Global scores were calculated by summing raw scores, with higher scores representing higher levels of depressive symptoms. Published alphas range from 0.84 to 0.90, with the Cronbach’s alpha of 0.84 in this study (Radloff, Reference Radloff1977).
Maternal anxiety at preschool
Maternal anxiety was measured with the Spielberger State-Trait Anxiety Inventory (STAI; Spielberger et al., Reference Spielberger, Gorsuch and Lushene1970). The STAI has both a state anxiety (A-State) and a trait anxiety (A-Trait) scale, and only the A-trait scale was used in the present study. Participants rated themselves on 20 items regarding general anxiety tendencies on a 4-point Likert scale from 1 (“not at all”) to 4 (“very much so”) with higher scores representing higher levels of anxiety. Cronbach’s alpha for the A-trait scale in this study was 0.90, consistent with a published range of 0.86 to 0.95 (Spielberger, Reference Spielberger1989).
Elementary school mental health and social outcomes
The Health and Behavior Questionnaire (HBQ) was used in the follow-up elementary school survey to assess mental health and social outcomes. Parents were asked to rate child social functioning and health condition. The HBQ ADHD (0.92), Conduct (0.69), Functional Impairment of the Child (0.68) and Family (0.83), and Oppositional Defiant (0.78), subscales were used in this study (Armstrong et al., Reference Armstrong and Goldstein2003). The Cronbach’s alphas in our sample ranged from .68−.92, indicating good internal reliability. Psychometric research on the HBQ has found it to be both a reliable and valid instrument (Essex et al., Reference Essex, Klein, Cho and Kalin2002; Lemery-Chalfant et al., Reference Lemery-Chalfant, Doelger and Goldsmith2008).
Data analysis
The study employed design-based multilevel structural equation models (Wu & Kwok, Reference Wu and Kwok2012) to examine the interrelationships among the preschool measures and elementary outcomes. The design-based approach was employed to adjust the underestimated standard errors due to the nested data structure (siblings clustered within families). In our preschool model, the temperament IC factor was measured by observer attention, observer hyperactivity, observer impulsivity, Lab-TAB snack delay, Lab-TAB gift, and parent-rated child IC. Observer hyperactivity was correlated with observer impulsivity. In preschool, the temperament IC factor and Stroop task were associated with WM and child externalizing behaviors. The temperament IC factor was also correlated with Stroop task. Preschool child externalizing behaviors, parent depression, and parent anxiety were also related to WM. Parent depression and parent anxiety were correlated with each other. Age and gender were considered as covariates for the preschool temperament IC factor, Stroop task, and WM. The parent-rater variance was accounted for in the analysis of parent-rated child IC, parent depression, parent anxiety, and child externalizing behaviors. These preschool measure relationships were examined simultaneously and established completely based on our prior study (Gagne et al., Reference Gagne, Barker, Chang, Nwadinobi and Kwok2021). As shown in Figure 1, in the current study, building on this previous work, we used the preschool temperament IC factor, Stroop task, WM, parent depression, parent anxiety, child externalizing behaviors, age, and gender to predict the elementary school outcomes. The elementary school outcomes were the externalizing behavior factor, which was composed of the HBQ ADHD, Conduct, and Oppositional Defiant subscales, and the impaired functioning factor, which was composed of the HBQ Functional Impairment of the Child and Family subscales. The analysis was performed using the Type = Complex routine in Mplus 8.8 (Muthén & Muthén, Reference Muthén and Muthén1998– 2017; Wu & Kwok, Reference Wu and Kwok2012), employing maximum likelihood model estimation with robust standard errors. To address missing data, full-information maximum likelihood (FIML) estimation was utilized (Larsen, Reference Larsen2011). Prior to conducting the analysis, several preliminary tests were carried out, including outlier and missing value detection, assumption checking, descriptive statistics, and correlation analysis.
Conceptual framework. Note. The relationships among preschool measures are established based on Gagne et al. (Reference Gagne, Barker, Chang, Nwadinobi and Kwok2021). At the same time, the preschool measures also longitudinally predict the elementary outcomes.
Results
Preliminary analysis
After testing for the assumption of normality using histograms, skewness, and kurtosis statistics, Stroop and maternal depression were positively skewed and were adjusted using square root transformations. Once these transformations were applied, all variables met the assumption of normality. Assumptions of lack of multicollinearity among predictors, lack of univariate and multivariate outliers, the assumption of homoscedasticity, and the multilevel assumption of homogeneity of level 1 variance were not violated.
Descriptive statistics, correlations and gender differences for child variables
Descriptive statistics and correlations amongst variables of interest were conducted and are listed in Table 1. As our previous work has already examined the relations between our preschool variables, in this paper we will focus on the preschool variables as predictors of the elementary school variables. Preschool observer ratings of impulsivity and parent ratings of IC and externalizing as well as maternal depression and anxiety were significantly linked to elementary school ADHD. Preschool observer ratings of hyperactivity and impulsivity and parent ratings of IC and externalizing were associated with elementary school conduct problems. Preschool observed impulsivity, parent-rated IC and maternal depression and anxiety were also correlated with elementary school ODD. Lastly, preschool observer ratings of impulsivity and maternal depression and anxiety were related to elementary school child and family functional impairment (preschool observed hyperactivity was also correlated with family functional impairment).
Descriptive statistics and correlations
Note. * p < .05; ** p < .01; *** <.001. FI = Functional Impairment.
Independent t-tests were used to test for gender differences and Cohen’s d was calculated to determine the effect sizes of the gender differences (Table 2). There were significant gender differences in preschool observer ratings of attention, hyperactivity and impulsivity, preschool parent ratings of IC, preschool Stroop, and elementary school conduct problems. Stroop was reverse coded in these analyses, meaning that lower means represents higher inhibitory control. The gender differences analyses show that girls have higher levels of preschool attention and IC, and lower levels of preschool hyperactivity and impulsivity, and lower elementary school conduct problems.
Gender differences amongst study variables
Note. Stroop is reverse scored and square root transformed values. CES-D is also square root transformed values.
The longitudinal associations between preschool measures and elementary school outcomes
The design-based multilevel structural equation model showed an acceptable fit to the empirical data: χ2 [104] = 142.527, p = .007; RMSEA = .043; CFI = .953; SRMR = .067 (Hu & Bentler, Reference Hu and Bentler1999; Schermelleh-Engel et al., Reference Schermelleh-Engel, Moosbrugger and Müller2003). Given that our previous publication extensively discussed the relationships among preschool measures, our focus in this study was on examining the longitudinal relationship between preschool measures and elementary outcomes. The results presented in Table 3 revealed negative associations between the preschool temperament IC factor and Stroop task, and both the externalizing behavior and impaired functioning factors during elementary school. In contrast, preschool parent depression showed a positive association specifically with the externalizing behavior factor in elementary school, while not showing a significant association with the impaired functioning factor. Additionally, we observed that participants with higher age exhibited a higher level of impaired functioning in elementary school, although age did not show a significant relationship with the externalizing behavior factor. Moreover, we found that preschool WM, parent anxiety, child externalizing behaviors, and gender did not significantly predict either of the elementary outcomes. Overall, the preschool measures could account for 42.5% of the variance in the elementary externalizing behavior factor and explain 33.3% of the variance in the elementary impaired functioning factor.
The longitudinal associations between preschool measures and elementary school outcomes
Note. The design-based multilevel structural equation model was conducted. For reasons of clarity, all covariances, uniquenesses, factor loadings, and preschool measure relationships are not shown. Values are standardized path coefficients; standard errors are in parentheses. Both externalizing behavior and impaired functioning factors are highly correlated (r = 0.896, p < .001). *p<05. n.s. stands for not significant (p ≥ .05).
Discussion
The goal of this investigation was to examine if preschool IC (both temperament and EF perspectives), WM, and externalizing behavior problems as well as maternal depression and anxiety at preschool, predicted adjustment in elementary school. Previous EF research indicated that IC and WM both have significant influences on social and behavioral adjustment (Blair & Razza, Reference Blair and Razza2007; Carlson & White, Reference Carlson, White and Taylor2013; Hughes & Ensor, Reference Hughes and Ensor2011; Rodriguez et al., Reference Rodriguez, Mischel and Shoda1989; Shoda et al., Reference Shoda, Mischel and Peake1990), and studies of IC from the temperament perspective have yielded similar results (Eisenberg et al., Reference Eisenberg, Cumberland, Spinrad, Fabes, Shepard, Reiser, Murphy, Losoya and Guthrie2001; Reference Eisenberg, Spinrad, Fabes, Reiser, Cumberland, Shepard, Valiente, Losoya, Guthrie and Thompson2004; Gagne et al., Reference Gagne, Saudino and Asherson2011, Reference Gagne, Chang, Fang, Spann and Kwok2018; Goos et al., Reference Goos, Crosbie, Payne and Schachar2009). Maternal depression and anxiety are also associated with IC and WM (Buss et al., Reference Buss, Davis, Hobel and Sandman2011; Hughes et al., Reference Hughes, Roman, Hart and Ensor2013; Pearson et al., Reference Pearson, Bornstein, Cordero, Scerif, Mahedy, Evans, Abioye and Stein2016), and have been found to be linked to externalizing and ADHD behavior problems in preschool (Gagne et al., Reference Gagne, Chang, Fang, Spann and Kwok2018). Our purpose was to add to the current literature by examining longitudinal relations between our preschool variables and adjustment in elementary school by using a multi-method family study design. We hypothesized that higher levels of preschool IC and WM and lower levels of preschool externalizing and maternal depression and anxiety would significantly predict better adjustment in elementary school (child age and gender were also analyzed). Our findings showed that preschool IC significantly predicted lower levels of externalizing behavior and impaired functioning in elementary school, but WM did not. Maternal depression at preschool was also significantly linked to elementary school externalizing behaviors. Interestingly, temperament-based IC was a stronger predictor of elementary school outcomes than EF-based IC.
As predicted, several of the correlations between our preschool temperament IC variables, preschool externalizing behavior problems and maternal mental health at preschool and our elementary school adjustment outcomes were significant, consistent with the previous literature (Casey et al., Reference Casey, Tottenham and Fossella2002; Hughes & Ensor, Reference Hughes and Ensor2011; Kim-Spoon et al., Reference Kim-Spoon, Deater-Deckard, Calkins, King-Casas and Bell2019). However, preschool WM and the preschool Stroop task that we used to assess IC from the EF perspective were not correlated with the elementary school variables. Significant gender differences emerged such that preschool girls had lower levels of observer-rated attention, hyperactivity and impulsivity, parent-rated IC, and Stroop than boys, consistent with previous research (e.g., Gagne et al., Reference Gagne, Miller and Goldsmith2013). In addition, at elementary school, girls had significantly lower conduct problems than boys. The results of the SEM analyses supported many of the correlational findings, with some exceptions. Most notably, the preschool EF IC task (Stroop) significantly predicted both externalizing and impaired functioning in elementary school in our SEM analyses, while temperament measures of preschool IC predicted these outcomes in both sets of analyses. It is likely that our multi-method measurement approach and the inclusion of child age and gender and maternal mental health variables in the models contributed to this pattern of findings, which supports and extends previous research across both EF and temperament conceptions of IC (Casey et al., Reference Casey, Tottenham and Fossella2002; Eisenberg et al., Reference Eisenberg, Cumberland, Spinrad, Fabes, Shepard, Reiser, Murphy, Losoya and Guthrie2001, Reference Eisenberg, Spinrad, Fabes, Reiser, Cumberland, Shepard, Valiente, Losoya, Guthrie and Thompson2004; Gagne et al., Reference Gagne, Saudino and Asherson2011; Goos et al., Reference Goos, Crosbie, Payne and Schachar2009; Hughes & Ensor, Reference Hughes and Ensor2011; Kim-Spoon et al., Reference Kim-Spoon, Deater-Deckard, Calkins, King-Casas and Bell2019).
Our predictions about maternal depression and anxiety were only partially confirmed. Maternal depression at preschool did predict elementary school externalizing in the SEM models, but not functioning, and maternal anxiety was not predictive of either elementary school outcome. This pattern of findings is somewhat inconsistent with the extant literature on this topic (Ashman et al., Reference Ashman, Dawson and Panagiotides2008; Gagne et al., Reference Gagne, Barker, Chang, Nwadinobi and Kwok2021; Gartstein et al., Reference Gartstein, Bridgett, Rothbart, Robertson, Iddins, Ramsay and Schlect2010; Murray et al., Reference Murray, Arteche, Fearon, Halligan, Goodyer and Cooper2011; Roman et al., Reference Roman, Ensor and Hughes2016; Spann & Gagne, Reference Spann and Gagne2016). Specifically, there is evidence of predictive effects for maternal anxiety and these outcomes (e.g., Buss et al., Reference Buss, Davis, Hobel and Sandman2011; Hughes et al., Reference Hughes, Roman, Hart and Ensor2013), however, some of our previous analyses with this sample also yielded fewer effects for maternal anxiety as compared to maternal depression (Gagne et al., Reference Gagne, Barker, Chang, Nwadinobi and Kwok2021). Because maternal depression at preschool has a longitudinal influence on elementary school externalizing behaviors, depressed mothers and their preschoolers are at risk.
Novel and impactful findings from the current study include preschool IC predicting adjustment in elementary school (WM was not a significant predictor), with the temperament-based conception of IC being a stronger predictor than the EF-based Stroop. These results suggest that preschool IC is an important influence on externalizing and functioning in elementary school, and that both emotional and cognitive aspects of preschool are relevant. Preschool interventions and programs supporting the development of IC are important areas of focus to help students’ making the transition from preschool to elementary school and should emphasize both the cognitive (EF) and emotional (temperament) elements of IC. Future research in this area could include a broader range of EF and temperament-based measures, employ a multi-method approach across age, extend studies longitudinally into middle childhood, and incorporate more representative samples in investigations.
Limitations and implications
The primary limitations of this study include sample size and composition, the use of sibling pairs, lack of father/partner data, a broad age range, shortcomings of some of the tasks and measures employed, and the number of years between the preschool and elementary school phases. A sample size of 99 pairs of siblings and their mothers is moderate, but the number of participants lost to follow-up in the elementary school phase although expected, decreased statistical power for longitudinal analyses. Demographically, the sample was composed of majority Caucasian participants with higher SES, which reduces generalizability. The preschool age range of three years was noteworthy; however, preschool age was accounted for in the SEM analyses. The usage of different Stroop tasks across the wide preschool age range can be viewed as a limitation, as lab measures were not uniform across participants, but the tasks had been used in previous studies in much the same manner and reflect age-appropriate assessment. Mothers are typically identified as the primary caregiver in most families in the U.S. (U.S. Census Bureau, 2022), but a growing number of fathers and grandparents provide primary care for children.
We did not find preschool WM to be a significant predictor of elementary school outcomes. A possible explanation for this is that the task was focused on spatial WM as opposed to verbal WM which may more accurately predict elementary school adjustment. Lower covariance between some of the preschool measures and the elementary school outcomes could be related to different reporters at each study phase. Although the use of lab-based observational measures of IC and WM is considered an asset of the study’s preschool phase, elementary school adjustment was based on parent ratings. Furthermore, the number of years that elapsed between the preschool and elementary school phases could have a temporal effect contributing to lower associations. Although we were interested in links between parent depression and anxiety and child outcomes, we acknowledge that parent depression and anxiety could cloud parent-ratings of child elementary school variables.
The present study contributes to the developmental literature by investigating longitudinal relations between preschool IC and WM and elementary school adjustment, and by the inclusion of maternal depression and anxiety. The family study design approach incorporating maternal mental health variables allows for the representation of the data across family members including both parents and children, permits the disentangling of unique effects at the family level in our analyses, and provides an illustration of the effects of the family environment. The longitudinal aspect of the research extending from preschool through early elementary school highlights the developmentally significant school transition for children. In addition, the multi-method approach to measuring preschool IC allowed us to examine it from both temperament and EF perspectives. Although we expected both domains of IC to predict elementary school outcomes, our findings provide initial confirmation that both are indeed relevant and that educators, researchers and practitioners should consider socio-emotional and cognitive aspects of IC in children transitioning from preschool to elementary school. In conclusion, this investigation is consistent with previous findings on the long-term effects of IC in the preschool and elementary school settings and support the existence and development of programs and interventions aimed at helping children and families improve IC skills before transitioning to school.
Acknowledgments
This research was supported by a Research Enhancement Program grant from the University of Texas at Arlington. Special thanks to all the families who participated in this project.
Competing interests
The authors declare none.
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