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In this study, we examined the developmental pathways from children’s family environment to school readiness within a low-income sample (N = 1,046), with a specific focus on the role of sustained attention. Six distinct factors of the family environment representing maternal parenting behaviors, the physical home environment, and maternal mental health at 3 years of age were explored as independent predictors of children’s observed sustained attention as well as cognitive and behavioral outcomes at 5 years of age. Children were grouped by poverty status (poor vs. near-poor). Results suggest specificity in the associations among attention (focused attention and lack of impulsivity) and its correlates, with different patterns emerging by poverty status group. Overall, the family environment was largely unrelated to children’s sustained attention. For both groups, focused attention was associated with receptive vocabulary; however, it partially mediated the association between maternal lack of hostility and receptive vocabulary only among the near-poor. In addition, lack of impulsivity was associated with both receptive vocabulary and externalizing behaviors but only for the poor group. Findings indicate sustained attention as a potential target for efforts aimed at enhancing school readiness among predominantly poor children.
Attention generally refers to a complex set of physiological and behavioral responses that are driven by stimuli in the environment or consciously controlled by the individual (Rueda, Posner, & Rothbart, 2005). One aspect of attention that has received increased interest in recent years is sustained attention. Sustained attention (Eisenberg et al., 2004; Ruff, 1986) describes a fundamental component of attention characterized by the ability to direct cognitive resources to a stimulus and to process information associated with the stimulus (Ruff & Rothbart, 1996; Sarter, Givens, & Bruno, 2001). Specifically, sustained attention allows children to intentionally focus attention on a particular target in the environment and to avoid distraction over time (Derryberry & Rothbart, 1997).
During the first year of life, sustained attention is supported by an orientating/investigative system, which allows infants to orient to and explore objects in the environment. The voluntary control of attention emerges toward the end of a child’s first year of life and continues to develop across the early childhood years. This development is the result of the maturation of a higher level attention system whose processes are largely dependent on the social context (Ruff & Rothbart, 1996). Extant literature suggests that an important influence on the development of sustained attention is the family environment (Dilworth-Bart, Khurshid, & Vandell, 2007; Groot, de Sonneville, Stins, & Boomsa, 2004; National Institute of Child Health and Human Development [NICHD] Early Child Care Research Network[ECCRN], 2003; National Institute of Child Health and Human Development [NICHD] Early Child Care Research Network [ECCRN], 2005). Collectively, the above studies support associations between a variety of maternal and home environment characteristics and individual differences in children’s sustained attention across early childhood. These findings have important implications for children’s school readiness, as there is accumulating research to suggest that sustained attention is associated with both cognitive and behavioral outcomes and may be a key mechanism underlying the association between family environment and children’s school readiness (Belsky, Fearon, & Bell, 2007; Miech, Essex, & Goldsmith, 2001; NICHD ECCRN, 2003).
In the present study, we address two limitations of the extant research on family environments, sustained attention, and school readiness. First, previous studies of the family environment and early attention have focused on one aspect of the family environment at a time or have used a composite measure of the family environment, thus masking the contribution of individual factors to children’s sustained attention. Thus, little is known about which specific aspects of the family environment influence sustained attention. This question is pressing in low-income populations, which typically score lower on measures of the family environment than middle- or high-income populations (Bradley, Corwyn, McAdoo, & García Coll, 2001; Hart & Risley, 1995; Lareau, 2000).
A second limitation of the existing research on children’s family environment, sustained attention, and school readiness is that the majority of studies have been conducted with a single data set— the NICHD Study of Early Child Care and Youth Development (SECCYD; Belsky et al., 2007; Dilworth-Bart et al., 2007; NICHD ECCRN, 2003, 2005). The sample in that data set represents a range of income levels. Of interest is whether the associations found in that sample among family environment, sustained attention, and school readiness generalize to children from exclusively low-income backgrounds. Limited research in this area shows that low-income children score lower than their peers on sustained attention (Dilworth-Bart et al., 2007; Miech et al., 2001). There is already ample evidence that low-income children enter school with fewer cognitive and behavior skills than other children (Denton & West, 2002). An as yet unstudied question is whether or to what degree low-income children’s poorer sustained attention explains their lower school readiness. Identifying the factors that promote low-income children’s school readiness, and the specific pathways through which they operate, should be a high priority for developmentalists and educators. Compared with other children, children from low-income families are at increased risk for school failure (Klebanov, Brooks-Gunn, McCarton, & McCormick, 1998; McLoyd, 1998) and behavior problems (Lengua, 2002; NICHD ECCRN, 2004).
The family environment plays a critical role in the development of sustained attention according to Bronfenbrenner’s bioecological model of human development, which views lives in context and considers person– environment interactions to be key to understanding development (Bronfenbrenner, 1979; Bronfenbrenner & Morris, 2006). Specifically, voluntary aspects of attention, including sustained attention, are thought to emerge in the social context of the early family environment and are believed to be shaped by the continuing interaction between the child and his/her environment. For example, parents play an important role in the development of children’s early attentional skills by sharing in their exploration and/or by exerting verbal control over attention and action (for review, see Ruff & Rothbart, 1996).
Research on associations between family context and sustained attention has focused almost exclusively on aspects of the mother– child relationship, such as parenting style and attachment status. For example, maternal responsiveness is consistently associated with higher levels of both concurrent and later attention (Belsky et al., 2007; Bornstein & Tamis-LeMonda, 1989; Findji, 1993). Maternal stimulation is associated with focused attention during play even in the first year of life (Belsky, Goode, & Most, 1980; Findji, 1993; Lawson, Parrinello, & Ruff, 1992). In contrast, negative aspects of the mother– child relationship, such as intrusiveness and insecure child–mother attachment, have been linked to poorer attention outcomes (Fearon & Belsky, 2004; Hubbs-Tait, Culp, Culp, & Miller, 2002). Thus, it appears that supportive parenting helps children sustain attention during activities and gradually assume responsibility for their cognitive monitoring, whereas unsupportive parenting limits children’s practice with attention regulation (Jacobvitz & Sroufe, 1987; Smith, Landry, Miller-Loncar, & Swank, 1997). Collectively, these studies demonstrate the responsiveness of attention to early socialization practices and highlight the importance of early mother– child interaction as a key context for the development of children’s attentional processes.
The effects of family environmental factors aside from mother– child interaction, such as stimulating learning materials, family routines, and maternal mental health, are well-documented with respect to young children’s academic and behavioral status (for review, see Bradley & Corwyn, 2006). The influence of these aspects of the broader family context on children’s attention has received less consideration. The few studies that do exist, however, suggest that family processes beyond the mother– child relationship have implications for sustained attention. For example, maternal depression has been negatively associated with sustained attention in early childhood (Breznitz & Friedman, 1988). Maternal stress has also been linked to attention problems, although in middle-childhood (Barry, Dunlap, Cotten, Lochman, & Wells, 2005). Moreover, the quality of the home environment, as indexed by the Home Observation for Measurement of the Environment (HOME; Caldwell & Bradley, 1984), was positively associated with children’s sustained attention (Dilworth-Bart et al., 2007). One study found that kindergarteners who came from noisier homes scored lower on attention skills (Heft, 1979).
Although the above-cited studies contribute to our understanding of how the family environment influences children’s sustained attention, they are limited in that they either focus exclusively on one factor or they examine a multifaceted composite without disentangling its components. Thus, in the present study we examine six distinct factors in the family environment (maternal warmth, maternal lack of hostility, maternal stimulation, the physical environment of the home, maternal depression, and maternal parenting stress), individually and simultaneously to assess their relative explanatory power. These results should inform prevention and intervention efforts because different family processes suggest different courses of action.
For example, we include measures of both maternal stimulation and the physical environment. The former captures the presence of toys and other stimulating objects, whereas the latter captures qualities of the home conducive to learning, such as quiet and lack of crowding. Given the importance of parental stimulation for early attention skills (Belsky et al., 1980; Findji, 1993; Lawson et al., 1992), the availability of stimulating objects may have special value separate and apart from a home environment that supports learning more generally. We also include measures of maternal mental health in addition to measures of parenting. Given the link between maternal mental health and parenting behaviors (Pett, Vaughan-Cole, & Wampold, 1994; Webster-Stratton & Hammond, 1988), maternal parenting stress and depression may fail to influence attention once maternal warmth, lack of hostility, and stimulation are controlled. Indeed, after accounting for mothers’ depression levels, parenting stress may not have an independent association with sustained attention. The present study is the first to test these mechanisms simultaneously. It is difficult to formulate hypotheses because of the lack of previous research in this area. However, the literature documenting that maternal mental health influences parenting behaviors suggests that depression and parenting stress may not be associated with attention in a model adjusting for parenting behaviors.
Attentional processes are thought to be fundamental to controlled cognitive activities and social behavior (Calkins & Fox, 2002; Eisenberg et al., 2005; Lawson & Ruff, 2004). Sustained attention, in particular, is thought to underlie goal formation and planning (Ruff & Rothbart, 1996) and cognitive competence in general (Sarter et al., 2001). A growing body of evidence supports these claims, as sustained attention has been associated with both cognitive performance (Carter & Swanson, 1995; Choudhury & Gorman, 2000) and behavioral regulation (Eisenberg et al., 2005; NICHD ECCRN, 2003) across early childhood. Furthermore, deficits in sustained attention have been linked with disorders, such as attention-deficit/hyperactivity disorder (Barkley, 1997; Rothbart, Posner, & Hershey, 1995), and are believed to be closely associated with executive function skills that underlie planning and goal-directed behavior, such as working memory (Levy & Hobbes, 1989; Silver & Feldman, 2005) and inhibitory control (Shoda, Mischel, & Peake, 1990). Recent research suggests that children acquire self-regulatory skills in the first five years of life sequentially, such that attentional control in toddlerhood enables behavioral and inhibitory control in preschool (Feldman, 2009). Thus, it is not surprising that difficulties in sustained attention are associated with both concurrent levels of school adjustment and decreases in school adjustment over time (Davies, Woitach, Winter, & Cummings, 2008).
In addition to its direct implications for children’s school readiness, sustained attention may also mediate the established association between the family environment and school readiness (e.g., Bornstein & Tamis-LeMonda, 1989; Caldwell & Bradley, 1984; Shonkoff & Phillips, 2000). In the NICHD SECCYD, it was found that children’s attentional processes at 54 months partially mediated associations between the quality of their family environment from 6 to 54 months of age and multiple school readiness outcomes at 54 months and first grade, including achievement and behavior (NICHD ECCRN, 2003). Using the same data set, Belsky et al. (2007) reported that attentional control in first grade partially mediated both the effect of maternal sensitivity at 54 months on externalizing behavior in third grade and the effect of maternal sensitivity in first grade on externalizing behavior in fifth grade.
If sustained attention is a key mechanism underlying the link between children’s early home environment and their school readiness, it may serve as an additional target for prevention and intervention programs remediating poor cognitive performance and problem behavior in early childhood. However, the current literature leaves unanswered questions regarding the generalizability of these pathways to low-income children and across specific domains of school readiness. First, past research demonstrating that sustained attention partially mediates the association between the family environment and school readiness has been conducted exclusively with the NICHD SECCYD, a mixed-income sample.
Second, a close reading of the literature suggests that one facet of attention may be associated with both cognitive and behavioral school readiness, whereas another facet may be associated with cognitive school readiness alone. This distinction hinges on past studies’ measures of sustained attention. NICHD ECCRN (2003) distinguished between errors of commission and omission on the continuous performance task (Rosvold, Mirsky, Sarason, Bransome, & Beck, 1956), in which children must quickly press a button when a target (but not a nontarget) stimulus appears onscreen. Errors of commission (pressing the button for a nontarget stimulus) assess impulsivity, whereas errors of omission (failing to press the button for a target stimulus) assess focused attention. Notably, errors of omission (focused attention) were associated with both cognitive and behavioral competence at 54 months, whereas errors of commission (impulsivity) were associated with only behavioral competence.
Further, when Belsky et al. (2007) reported that attention mediated the association between maternal sensitivity and externalizing behavior, their measure of attention relied exclusively on errors of commission (impulsivity). Thus, it is likely that impulsivity may be more strongly or even solely linked to behavioral school readiness, whereas focused attention may be linked to both cognitive and behavioral school readiness. Although the above results were obtained with a mixed-income sample, they find support from a recent study of a Head Start population in which sustained attention, measured by the Leiter International Performance Scale—Revised (Roid & Miller, 1997) as in the present study, covaried with cognition but not behavior (Rhoades, Greenberg, & Domitrovich, 2009). Therefore, we expect that in the present low-income sample, focused attention will mediate associations between the family environment and both cognitive and behavioral school readiness, whereas lack of impulsivity will mediate associations between the family environment and behavioral school readiness.
The main objective of this study was to increase our understanding of sustained attention and its correlates across early childhood among low-income children. Children from low-income families enter school with poorer academic skills than other children (Denton & West, 2002) and are more likely to develop cognitive and behavior problems over the grade school years (Lengua, 2002; McLoyd, 1998; NICHD ECCRN, 2004; Schmitz, 2003). In light of past research indicating that sustained attention may be a key ingredient of school readiness, it is imperative that we identify its predictors and understand its implications for cognitive and behavioral competence. The first aim of this study was to examine the longitudinal association between the family environment and children’s sustained attention. Of interest is whether attention is differentially influenced by maternal warmth, lack of hostility, maternal stimulation, the physical environment of the home, maternal depression, and maternal parenting stress. All of these factors have been individually linked to young children’s attention but not in comprehensive models that adjust for the other factors.
The second aim of the study was to examine the concurrent link between two facets of sustained attention—focused attention and lack of impulsivity—and both cognitive and behavioral school readiness, with interest in the possibility of differential associations across domains of competence. Although there are multiple components of school readiness (Kagan, Moore, & Bredekamp, 1995), we focus on cognition and behavior because they are associated with both family environment and attention, and because their status at school entry strongly predicts school success and antisocial behavior later in life (Ensminger & Slusarick, 1992; Feinstein & Bynner, 2004; Moffitt, Caspi, Rutter, & Silva, 2001). In particular, we assess receptive vocabulary because it serves as a proxy for general cognitive ability, which is associated with focused attention (Choudhury & Gorman, 2000), one of our two facets of attention. Likewise, we examine externalizing behavior (rather than internalizing or prosocial behavior) because it requires the restraint of impulsivity, the other component of attention in this study. The third study aim was to explore the associations among the family environment, sustained attention, and school readiness within a single model, with a specific interest in the potential for sustained attention to mediate links between the family environment and school readiness.
Finally, the fourth aim of the study was to compare the results for the previous study aims across poor and near-poor subgroups within a low-income sample. Previous research has demonstrated nonlinear associations between income and the physical and psychosocial quality of the home environment as well as children’s school readiness (Dearing, McCartney, & Taylor, 2001; Dearing & Taylor, 2007; Votruba-Drzal, 2003). That is, the same increment in income results in a steeper improvement in the home environment or positive child outcome in lower income families than in higher income families. Other developmental processes may vary between children who live below the poverty line and their more advantaged peers either because poor children are more responsive to stimuli or because their developmental timetable lags behind other children’s. In the present study, we distinguish between two subgroups within a low-income sample: the poor (below the poverty line) and the near-poor (above the poverty line but with an income-to-needs ratio of less than 3). Given the urgent need for educational and behavioral interventions with low-income children, it is worthwhile to document whether there are differences in associations among the family environment, sustained attention, and school readiness across the poverty line divide.
The Fragile Families and Child Wellbeing Study follows a birth cohort of approximately 4,900 children in 20 cities across the United States. By design, children born to unmarried parents were oversampled (n = 3,712 vs. n = 1,186 children born to married parents). The cities were selected to be representative of all U.S. cities with populations of 200,000 or more (for further information on sample selection, see Reichman, Teitler, Garfinkel, & McLanahan, 2001). Hospitals were sampled within cities, and births were sampled within hospitals. Mothers were first interviewed in the hospital within 48 hr of giving birth, and fathers were interviewed as soon as possible thereafter. As part of the core study, both mothers and fathers were interviewed by phone when the child was 1, 3, and 5 years of age.
We draw on data from a substudy of the core called the In-Home Longitudinal Study of Preschool Aged Children. At the phone surveys taken at 3 and 5 years of age, mothers were invited to take part in an in-home data collection substudy. Mothers who agreed to participate (79% at 3 years of age and 91% at 5 years of age) were visited by data collectors in their homes. During the home visit at both time points, mothers were interviewed, the home environment was observed, and children were directly assessed. Families who had moved out of the area were eligible to complete the interview by phone. In 18 of the 20 cities, an additional module called Child Care and Parental Employment (CCPE) in Fragile Families was administered. Children’s attention was assessed as part of this module.
Of the 2,848 families who participated in the CCPE module at the 3 years of age wave, 1,758 (62%) were eligible for inclusion in our analytic sample because they had complete information on their family environment. The most common reason for incomplete information was mode of data collection; phone participants lacked observational items that contributed to the Maternal Warmth, Lack of Hostility, and Physical Environment scales. Eligible cases tended to be more socioeconomically disadvantaged than ineligible cases. It is possible that families who moved out of the area did so because of improving economic circumstances. Eligible cases were also more likely to be African American than were ineligible cases (58% vs. 40%).
Of the 1,758 cases with family environment information, approximately one quarter (n = 488) were excluded because they were missing data on child attention or school readiness at 5 years of age. Missingness was due to attrition in approximately half these cases and to participation by phone (which prevented direct assessment of the child) in the other half. Cases without child attention or school readiness data tended to be more socioeconomically advantaged. Finally, to ensure that the analytic sample was exclusively low-income, 224 cases were dropped because their incomes were 300% or more of the federal poverty threshold. The final analytic sample (n = 1,046) differed from the original CCPE sample in that it was no longer representative of midsized U.S. cities. The analytic sample contained more African American (63% vs. 51%) and fewer Hispanic (20% vs. 23%) mothers than the original sample. Fewer mothers were college educated (26% vs. 36%) or married or cohabiting (41% vs. 50%).
In sum, members of the analytic sample were universally socioeconomically disadvantaged. Of the mothers, 54% met the federal definition of poverty at baseline, and the remaining 46% fell between 100% and 300% of the poverty threshold. Fifty-nine percent lived without a spouse or partner. Thirty-eight percent did not complete high school, 36% completed high school or obtained a grade equivalency diploma, and 26% attended some college. The mean age at first birth was 20 years. Sixty-three percent were African American, 20% were Hispanic, and 14% were European American. All but a negligible number of the mothers co-resided with their children at 3 and 5 years of age and were the primary caregivers.
Data on the children’s family environment were collected at 3 years of age, and data on children’s attention and school readiness were collected at 5 years of age. Home visits at 3 and 5 years of age were conducted by data collectors who were trained on both interviews and direct child assessments. The maternal interview covered family routines, parenting behaviors, and the child’s behavior problems. Data collectors made observations on the mother and child’s interaction and the interior of the residence. Data collectors also measured the child’s attention and cognitive ability.
There are six measures of the family environment at 3 years of age. The first three tap maternal parenting behavior, one taps the physical environment of the home, and the last two tap maternal mental health. The first measure of parenting assessed maternal warmth via data collector observation during the home visit. There were four dichotomous items (α = .74; sample item: “mother’s voice conveys positive feeling when talking to or about child”). The second parenting measure, maternal lack of hostility, comprised four dichotomous items based on data collector observation (α =.80; sample item: “mother does not scold, derogate, or criticize child more than once”). The third parenting measure captured maternal stimulation and included eight items (α = .50; sample item: “child has toy that lets her/him play music”) per maternal report at the home visit. The fourth measure of parenting assessed the quality of the home’s physical environment and included four dichotomous items observed by the data collector during the home visit (α = .68; sample item: “home not too noisy from noise outside”). Items for the above four scales were drawn from the HOME (Caldwell & Bradley, 1984) and the Homelife Interview (Leventhal, Selner-O’Hagan, Brooks-Gunn, Bingenheimer, & Earls, 2004). For all four scales, items were summed so that higher scores indicate higher quality.
The first measure of maternal mental health captured maternal depression. During the phone interviews for the core sample at 3 years of age, mothers were administered Section A of the Composite International Diagnostic Interview Short Form (Kessler, Andrews, Mroczek, Ustun, & Wittchen, 1998). Seven items describing depressive symptoms were drawn from the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) definition of a major depressive episode. Responses were summed (α = .92) to generate a count of depressive symptoms during the past year.
The second measure of maternal mental health assessed maternal parenting stress using items drawn from the Parenting Stress Index (Abidin, 1995). At the 3 years of age home visit, mothers endorsed 11 items describing stress on a 5-point scale ranging from 0 (strongly disagree) to 4 (strongly agree). Sample items include “You feel trapped by your responsibilities as a parent” and “You feel alone and without friends.” Items were summed (α = .85), as in other studies (e.g., Taylor, Guterman, Lee, & Rathouz, 2009). Higher scores on both parenting stress and depression indicate poorer mental health.
Children’s sustained attention was measured during the 5 years of age home visit. The attention sustained task from the Leiter International Performance Scale—Revised assessed children’s ability to maintain attention to a specific stimulus and to suppress their impulses (Roid & Miller, 1997). Children were shown a picture of a variety of objects scattered throughout the page. There was a target object at the top of the page, and children were asked to put a line through as many of the objects matching the target as possible without accidentally crossing out any other objects. Children completed four timed trials. Two scales were yielded. The number of correct responses (crossouts of objects matching the target) reflects the child’s focused attention, whereas the number of incorrect responses (cross-outs of objects not matching the target) was reversed to reflect the child’s lack of impulsivity. These scales were named Focused Attention and Lack of Impulsivity, respectively.1 Scores are standardized against a national norming sample with a mean of 10 (SD = 3). The task has high internal reliability (α = .83) for children 4–5 years of age and good test–retest reliability (r = .85).
Cognitive school readiness was captured by the Peabody Picture Vocabulary Test, Third Edition (PPVT–III; Dunn & Dunn, 1997b), administered at the 5 years of age home visit. This test assesses the child’s receptive vocabulary by asking the child to point to one of four pictures that best depicts the word read aloud. The PPVT–III is nationally normed by age, with a standard score of M = 100 (SD = 15). This measure has high internal (α = .93) and test–retest (r = .92) reliability for preschoolers (Dunn & Dunn, 1997a). In addition, this measure is correlated with measures of aptitude and school readiness (Ladd, 1990) and has been used as a measure of cognitive competence across early childhood (Blair & Razza, 2007; Culp, Hubbs-Tait, Culp, & Starost, 2000).
Behavioral school readiness was captured by a measure of children’s externalizing problems. When the child was 5 years of age, mothers reported on all but three items from the Externalizing subscale of the Child Behavior Checklist/4 –18 (Achenbach, 1991). For each item describing a behavior problem, mothers rated whether it was not true (0), sometimes true (1), or very true (2) of her child. Sample items include “child argues a lot” and “child has temper tantrums or hot temper.” There were 30 items in all (α = .86), which were summed. Higher values indicate more externalizing behaviors.
A variable indicating whether the family was in poverty at 3 years of age was coded affirmatively if the household income fell below the poverty threshold established by the U.S. Census Bureau for the preceding calendar year. The sample was then split into two groups: the poor (below the poverty threshold; n = 515) and the near-poor (above the poverty threshold but below 300% of the poverty threshold; n = 467).
Characteristics of the child and his or her family were included as controls in all multivariate models. These characteristics were selected on the basis of previous literature showing their associations with family environment, sustained attention, and school readiness. Except where noted, all were captured at baseline; in a few instances, characteristics were measured at the time point closest to measurement of the family environment.
Indicators were created to reflect whether the child was male or born with low birth weight (<2,500 g). The child’s temperament as an infant was captured at the 1 year of age phone interview using the mean of three items (α = .60) drawn from the Emotionality scale of the Emotionality, Adaptability, Sociability (EAS) Temperament Survey for Children (Buss & Plomin, 1984). Mothers were asked to rate how well three items described their child (“often fusses and cries,” “gets upset easily,” and “reacts intensely when upset”) on a 5-point scale ranging from 1 (not at all like my child) to 5 (very much like my child). Maternal age at first birth was also reported at the 1 year of age phone interview.
Race was coded according to maternal self-report as European American non-Hispanic, African American non-Hispanic, Hispanic, or other. Maternal education was coded as less than high school, high school graduation or general equivalency diploma, or some college or more. Maternal marital status as of the in-home visit at 3 years of age was coded as married/cohabiting or single. A ratio of children to adults living in the household at 3 years of age was calculated on the basis of a household roster. The mother’s receptive vocabulary was assessed by the PPVT–III (Dunn & Dunn, 1997b), administered at the 3 years of age home visit. Scores are standardized by age against a national norming sample (M = 100, SD = 15). Last, city indicator variables were also added as controls.
Table 1 presents the percentages or means, standard deviations, and sample sizes for the control, predictor, mediator, and outcome variables by poverty group status. All variables were normally distributed with adequate skew and kurtosis. Zero-order correlations among the variables are displayed in Table 2 for the poor and near-poor groups. As expected, significant associations were found across the constructs of interest for both poverty status groups, suggesting that family environment, sustained attention, and children’s school readiness outcomes are interrelated. There were some differences by poverty status group. Maternal lack of hostility was positively associated with focused attention only in the near-poor group, whereas maternal stimulation was positively associated with focused attention only in the poor group. Lack of impulsivity was negatively associated with externalizing in the poor group only.
Data analysis involved a two-stage process. In the first stage, we identified unique associations between the family environment and the two facets of sustained attention, which was the first aim of our study. In the second stage, we regressed school readiness outcomes on the family environment and both facets of sustained attention. This analysis addressed the second and third aims of our study, namely to identify associations between sustained attention and school readiness and to test whether sustained attention mediated associations between the family environment and school readiness. Given that the last aim of this study was to explore differential associations among these factors between poor and near-poor participants, all analyses were conducted separately by poverty status group.
Regression analyses were consistent with Baron and Kenny’s (1986) four criteria for mediation. Thus, for mediation to be supported, the following conditions had to be satisfied: (a) family environment should predict school readiness, (b) family environment should predict attention, (c) attention should predict school readiness, and (d) the relation between the family environment and school readiness should be reduced or eliminated when both family environment and attention were entered together into the model. Separate hierarchical regression models were run for the two measures of school readiness, receptive vocabulary and externalizing behaviors. In Step 1 of the model, the school readiness outcome was regressed on the six measures of family environment and all controls. In Step 2, children’s focused attention and lack of impulsivity were added as independent predictors. If the coefficient for a family environment measure decreased from Step 1 to Step 2, a Sobel test (Sobel, 1982) was conducted to determine whether attention mediated the association between that measure of family environment and that outcome. Both focus and lack of impulsivity were considered as possible mediators. Formal mediation tests were conducted in STATA using sgmediation, as suggested by Dearing and Hamilton (2006). This program uses bootstrap analyses to estimate the indirect effect of the predictor variable on the dependent variable through the mediator variable. Bootstrap analysis involves drawing a large number of samples (with replacement) from a data set, computing the indirect effect for each sample, and then generating an average indirect effect across all samples.
As previously noted, all regression models included controls for child gender, low birth weight, infant temperament, maternal age at first birth, maternal cognitive ability, maternal race/ethnicity, maternal education, marital status, household child:adult ratio, and city. The number of cases with valid values varies across the two school readiness outcomes and is therefore indicated in tables.
Ordinary least squares regressions were conducted to explore the longitudinal associations between the family environment at 3 years of age and children’s focused attention and lack of impulsivity at 5 years of age. Of particular interest was whether the six facets of the family environment (maternal warmth, maternal lack of hostility, maternal stimulation, physical environment, maternal depression, and maternal parenting stress) would predict attention independent of one another. Thus, measures of attention were regressed simultaneously on all measures of the family environment plus the controls listed above. Focused attention and lack of impulsivity were evaluated in separate models that included the other attention measure as a covariate.
For the near-poor group, lack of maternal hostility (β =.11, p < .05) significantly predicted children’s focused attention, independent of the other five family environment variables (see Table 3). In addition, the link between the physical environment (β = .09, p < .10) and focused attention was marginally significant. The other measures of the family environment did not predict focused attention for this group. Results from analyses predicting lack of impulsivity suggest marginal associations with maternal depression and parenting stress among the near-poor. The other measures of the family environment did not predict lack of impulsivity for this group. For the poor group, none of the family environment variables predicted focused attention or lack of impulsivity. Therefore the second criterion for mediation (an association between family environment and attention) was not satisfied, and formal testing for mediation was not necessary in this group.
Hierarchical regressions were conducted to determine whether children’s family environment at 3 years of age and attention at 5 years of age were associated with school readiness at 5 years of age. For the near-poor group, as shown in Step 1 of Table 4, maternal lack of hostility (β = .14, p < .01) was significantly associated with receptive vocabulary, such that children whose mothers displayed less hostility scored higher on receptive vocabulary. In addition, the physical environment (β = .12, p < .01) reached significance, indicating that children with higher scoring physical environments had larger receptive vocabularies.
In Step 2, children’s focused attention (β = .32, p < .001), but not lack of impulsivity (β = .06, ns), was strongly associated with receptive vocabulary. Specifically, focused attention accounted for 8% of the unique variance in children’s receptive vocabulary, F(1, 417) = 52.04, p < .001 (not shown). Given that maternal lack of hostility had significantly predicted children’s focused attention (see Table 3), a Sobel test was conducted to formally test whether focused attention mediated the association between lack of hostility and children’s receptive vocabulary. The Sobel test was significant (z = 2.27, p < .05; results not shown) and indicated that focused attention mediated 25.25% of the total effect of maternal lack of hostility on children’s receptive vocabulary. Although the physical environment predicted receptive vocabulary, because it had been only marginally associated with focused attention, a formal test for mediation was not performed. Last, maternal stimulation and maternal parenting stress were marginally significant predictors of receptive vocabulary.
Similar analyses were conducted using externalizing behaviors as the outcome variable. As shown in Step 1 of Table 4, maternal parenting stress (β = .20, p < .001) was the only aspect of the family environment that predicted externalizing behaviors. Neither facet of sustained attention emerged as a significant predictor of externalizing behaviors. Therefore, it was not possible for attention to mediate the association between maternal parenting stress and externalizing behaviors in this group.
The results from a hierarchical regression model predicting receptive vocabulary from family environment and attention within the poor group are displayed in Table 5. The results from Step 1 show that maternal stimulation (β =.10, p < .05) predicted receptive vocabulary, such that children with more stimulating mothers had larger receptive vocabularies. The physical environment (β = .09, p < .05) also reached significance, with higher scoring children having larger receptive vocabularies. Finally, children whose mothers scored higher on parenting stress scored lower on receptive vocabulary (β = −.13, p < .001).
In Step 2, both focused attention (β = .32, p < .001) and lack of impulsivity (β =.14, p < .001) significantly predicted receptive vocabulary. Specifically, attention accounted for 11% of unique variance in receptive vocabulary, F(2, 469) = 53.31, p < .001. Thus, children with better attention demonstrated higher levels of receptive vocabulary in the poor group. However, because none of the family environment factors had predicted either facet of attention, it was not possible that attention mediated associations between the family environment and receptive vocabulary.
Similar analyses were performed to examine the influence of the family environment and attention on poor children’s externalizing behaviors (see Table 5). The results from Step 1 show that maternal warmth (β = −.13, p < .01) predicted externalizing behaviors, such that children with warmer mothers demonstrated fewer externalizing behaviors. In addition, children whose mothers scored higher on parenting stress (β = .17, p < .001) scored higher on externalizing behaviors. Maternal depression was marginally associated with externalizing behaviors.
In Step 2, children’s lack of impulsivity (β = −.09, p < .01), but not focused attention (β = .03, ns), was significantly associated with externalizing behaviors. Children who scored higher on lack of impulsivity had fewer externalizing behaviors. Lack of impulsivity accounted for 1% of the unique variance in children’s externalizing behaviors, F(1, 468) = 3.88, p < .05 (not shown). Given that none of the family environment factors had predicted lack of impulsivity in this group, mediation analyses were not conducted.
The present study extends our understanding of the developmental pathways to school readiness for low-income children by highlighting the role of sustained attention in this process. Individual differences in sustained attention were correlated with selected aspects of the family environment and both dimensions of school readiness. However, the findings indicate specificity in the associations between attention and its correlates that differ by poverty status.
In particular, this study makes four significant contributions to the attention literature. First, the present study increases our understanding of the specificity of the longitudinal association between the family environment and sustained attention by examining distinct facets of both constructs. Specifically, results suggest that maternal parenting behavior (specifically, lack of hostility), but not maternal mental health, predicted children’s focused attention during early childhood in the near-poor group. In contrast, no measures of the family environment predicted either facet of sustained attention in the poor group.
Second, this study furthers our understanding of the specific role of sustained attention in children’s school readiness. Focused attention was concurrently associated with cognitive school readiness (receptive vocabulary) among both poverty status groups. Lack of impulsivity was associated with both cognitive and behavioral school readiness but only in the poor group. Third, the current study extends the examination of sustained attention as a mechanism underlying associations between the family environment and school readiness to low-income children. Results support focused attention as a partial mediator of the association between the family environment (specifically, maternal lack of hostility) and children’s cognitive school readiness (specifically, receptive vocabulary) for the near-poor group. Fourth, the results of this study suggest that even within a low-income sample, the associations between sustained attention and its correlates differ by poverty status. This finding has important implications for promoting school readiness outcomes among children from predominantly low-income backgrounds.
Surprisingly, there were few associations between the family environment at 3 years of age and children’s sustained attention at 5 years of age in this low-income sample. In fact, in the poor group, the family environment did not predict sustained attention at all. In the near-poor group, only one facet of the home environment— maternal lack of hostility—predicted one facet of sustained attention—focused attention. Overall, then, the present study fails to replicate several previously obtained associations between the family environment and sustained attention. We propose three possible explanations. The first two refer to measurement issues that may have limited our ability to detect associations between the family environment and sustained attention, and the last considers the possibility that these associations do not exist for low-income children.
First, our measure of sustained attention differs from the one in the NICHD SECCYD, the study on which most conclusions to date have been based. In that study, the Continuous Performance Test (CPT; NICHD ECCRN, 2003) was used, whereas in the Fragile Families study, the Leiter International Performance Scale—Revised was used. Although these tests tap similar facets of attention, the discrepancies in their formats are nontrivial. The difference between paper (Leiter) and computer administration (CPT) is germane in this respect. The Leiter task, unlike the CPT, does not actively alert children to nontarget stimuli. Thus, children may be more tempted to make impulsive errors with the CPT. In addition, children’s commission errors are visible to the child throughout the Leiter assessment, which contrasts with the CPT, where stimuli appear and disappear quickly on the computer screen. The CPT task also captures children’s attention over a longer period of time. It is possible that the CPT measures have better psychometric properties than the Leiter measures, which would make it easier to detect associations between attention and the family environment in the NICHD SECCYD than in the Fragile Families study.
A second possible explanation for the weak associations in the present study between the family environment and sustained attention is that our measures of the family environment were insufficiently sensitive. It may be that the specificity in developmental pathways we sought to achieve by disaggregating the HOME scales came at the cost of statistical power (given that fewer items decrease a scale’s reliability). It may also be that items from a checklist completed over the course of the home visit were too blunt. Past findings from the NICHD SECCYD linking the family environment to sustained attention used a measure of the family environment that incorporated both checklist items and maternal scores on sensitivity and stimulation during a videotaped interaction; moreover, that measure combined scores from multiple waves between birth and 54 months (NICHD ECCRN, 2003). It may not have been possible to replicate the NICHD SECCYD’s findings in the Fragile Families study given the lack of robustness of the latter’s family environment measures.
For example, maternal stimulation may have failed to predict sustained attention in our sample because our measure assessed the number of stimulating toys in the home rather than a mother’s stimulating behavior per se. Past research indicates that stimulating interactions and materials promote sustained attention by facilitating joint attention episodes with objects or people (Saxon, Frick, & Colombo, 1997; Smith et al., 1997). Our measure of stimulation may have assessed the potential for stimulating interactions rather than their actual frequency. Optimally, a test of the influence of the family environment on sustained attention would measure parenting during an episode of parent– child play or problem solving. Recent research suggests that a combination of parental contingency and stimulation is particularly facilitative of infants’ focused attention (Miller, Ables, King, & West, 2009). Our measures of parenting did not tap this combination of behaviors.
Last, this study’s failure to find associations between the family environment and sustained attention may reflect real developmental differences between the low-income children in our sample and their higher income peers. For example, model results indicate that for the poor group only, maternal cognitive ability predicted focused attention, and infant temperament predicted lack of impulsivity (not shown). These results suggest that genetic or constitutional factors may be especially influential for sustained attention among the poorest children. It is also possible that experiences of trauma and deprivation are what matter most for sustained attention among low-income children. Exposure to violence, homelessness, poor nutrition, sleep deprivation, and frequent changes in household composition all covary with poverty. Any one of these might dwarf the importance of other environmental influences on attention. Future research will be needed to test these hypotheses. For the time being, this study’s findings should be viewed as tentative and in need of replication.
In the near-poor group, there was one aspect of the family environment that significantly predicted sustained attention. Children whose mothers were least hostile at 3 years of age had the greatest focused attention at 5 years of age. Mothers who are hostile toward their child may place greater importance on their own feelings than their child’s and pay limited attention to their children’s cues. Previous research indicates that intrusiveness negatively affects attention because it devalues the child’s attentional focus and makes it difficult for the child to make connections between elements in his/her environment (Hubbs-Tait et al., 2002; Miller et al., 2009). It is also possible that the children of hostile mothers are too anxious to attend to tasks requiring focused attention. Recent experimental evidence shows that negative mood leads to distractability during an attention task (Smallwood, Fitzgerald, Miles, & Phillips, 2009).
Further support for specificity in the developmental pathways was reflected by the direct and indirect effects of the family environment on children’s school readiness. With respect to direct effects, the associations between the family environment and both the cognitive and behavioral dimensions of school readiness are consistent with previously reported findings. Overall, the pattern suggests that maternal parenting behavior and the physical environment matter more for children’s cognitive school readiness, whereas maternal mental health was more strongly associated with children’s behavioral school readiness. It is notable that maternal mental health predicted children’s behavior even after controlling for maternal parenting behaviors, which are themselves adversely affected by poor maternal mental health (Lovejoy, Graczyk, O’Hare, & Neuman, 2000). Maternal stress and depression are each associated with insecure child–parent attachment (Atkinson et al., 2000), which undermines children’s peer relations and classroom behavior (Berlin, Cassidy, & Appleyard, 2008). Social learning is also thought to explain the association between poor maternal mental health and children’s behavior problems. Specifically, distressed mothers role model negative cognitions, poor emotional regulation, and ineffective problem solving (Goodman, 2007).
Interestingly, there were some differences in the patterns between the family environment and school readiness outcomes across the poverty status groups. Specifically, receptive vocabulary was predicted by maternal stimulation among the poor group and lack of maternal hostility among the near-poor group. The failure to find a significant link between maternal stimulation and receptive vocabulary among the near-poor may well have been a power problem, as the association approached significance. It is not immediately apparent why maternal lack of hostility failed to predict receptive vocabulary in the poor group. Previous research suggests that early maternal punitiveness negatively impacts children’s cognitive competence in kindergarten within both lowincome and more advantaged samples (Culp et al., 2000; Fagot & Gauvain, 1997; Olson, Bates, & Kaskie, 1992). Similarly, it is unclear why maternal warmth only predicted externalizing behaviors in the poor group. One possibility is that there was a ceiling effect for maternal warmth in the near-poor group, given its high mean score (3.54 out of a possible total of 4).
The pattern of differential associations between predictors and outcomes extended to the link between sustained attention and school readiness. As hypothesized, focused attention was concurrently associated with children’s cognitive school readiness at 5 years of age for both poverty status groups. This finding adds to a growing body of literature that demonstrates the importance of attentional skills for children’s cognitive performance (Carter & Swanson, 1995; Choudhury & Gorman, 2000). Specifically, the ability to intentionally focus attention is believed to be especially critical for reading and language competencies (Tamis-LeMonda & Bornstein, 1989; Velting & Whitehurst, 1997).
Moreover, focused attention emerged as a partial mediator of the association between maternal lack of hostility at 3 years of age and children’s receptive vocabulary at 5 years of age, although only among the near-poor group. The NICHD SECCYD found that focused attention mediated associations between the family environment and achievement but not cognition (NICHD ECCRN, 2003). Although that measure of cognition included receptive vocabulary, it also included measures of short-term memory and auditory processing. Therefore, it is difficult to compare results across studies. Taken together, however, the studies suggest that focused attention contributes to achievement, cognition, or both at the time of school entry. Although further research is needed to enhance this body of knowledge, the evidence so far suggests that focused attention may be a target for future interventions aimed at improving school readiness.
Although we hypothesized that focused attention would be associated with behavioral as well as with cognitive school readiness, no such association was found. As expected, lack of impulsivity was associated with behavioral school readiness but only in the poor group. The failure to find this association in the near-poor group is inconsistent with past research suggesting that impulsivity has important implications for children’s externalizing behaviors (Belsky et al., 2007; Eisenberg et al., 2005; NICHD ECCRN, 2003). Moreover, contrary to expectation, we found that lack of impulsivity predicted cognitive school readiness, though in the poor group only. That is, lack of impulsivity was associated with receptive vocabulary among the poor.
The associations between lack of impulsivity and both cognition and behavior in the poor group suggest that impulsivity may have farther reaching effects for poor children than for their more advantaged peers. Although it is true that poor children scored both lower on focused attention and higher on impulsivity, it is not the case that those two facets of attention necessarily covary, given that it is possible to be distracted without being impulsive. However, the correlation between those two facets of attention was higher in poor than in nonpoor children (see Table 2), suggesting a special association between them in poor children. Lack of impulsivity was also more strongly correlated with receptive vocabulary in poor than in nonpoor children. One possible explanation is that it is extremely difficult for poor children to sit still and concentrate during paper-and-pencil tests, particularly ones that are intentionally boring (such as sustained attention) and/or repetitive (such as receptive vocabulary). Poor children are read to less frequently by their parents than nonpoor children (Bradley et al., 2001), and book-reading activities largely simulate our tests of attention and cognition. Children who are more habituated to test-like activities will have had more practice suppressing their impulses in such situations, putting poor children at a disadvantage.
Although the current study adds to our understanding of sustained attention and its correlates among low-income children, it is not without limitations. First, the methods of measurement used in this study could have influenced the findings. Three of the six measures of the family environment relied exclusively on maternal report, as did the measure of behavioral school readiness, resulting in shared method variance. It is possible that a different pattern of results could have emerged had children’s behavior been directly assessed or teacher-reported. Teacher-reported behavior would have been preferable to parent report, given that behavior in the classroom is more relevant than behavior at home to school readiness.
A second limitation of the current study is that our mediator, sustained attention, was observed at the same point in time as our school readiness outcomes. Although we were unable to measure attention before 5 years of age, developmental theory suggests that observed scores at that age reflect individual differences in voluntary attention originating in the second year of life. Specifically, according to Feldman’s (2009) hierarchical–integrative perspective, emotion regulation in infancy is a developmental precursor of attentional regulation during toddlerhood, which in turn is a developmental precursor of behavioral regulation in preschool. Thus, both sustained attention and school readiness may be observed at 5 years of age, but the former temporally preceded and even facilitated the latter, as attention skills serve as a lower order foundation for the acquisition of cognitive and behavior competence.
Finally, a third limitation of the current study is its exclusive focus on sustained attention as a mechanism through which family environment influences school readiness. Although sustained attention is an important mediator of this link, it is only one of several key self-regulatory processes that could fulfill this role. For example, executive function and effortful control are two additional facets of self-regulation that deserve consideration, as both are influenced by the family environment and have important consequences for children’s school readiness (Blair, 2002; Kochanska, Murray, & Harlan, 2000; Li-Grining, 2007). Moreover, although there is overlap among various aspects of selfregulation, the limited research addressing this issue supports specificity in the family environmental predictors of the different self-regulatory processes (Li-Grining, 2007) and suggests that each can make unique contributions to school readiness outcomes (Blair & Razza, 2007; NICHD ECCRN, 2003).
In conclusion, this study is the first to examine specific associations among the family environment, sustained attention, and school readiness within an exclusively low-income sample. Results indicate that the links among sustained attention and its correlates may diverge for lower and higher income children. They may even diverge for children living below and just above the poverty line. Further study is needed to replicate these findings and to test additional hypotheses about sustained attention in lowincome children. Albeit tentatively, this study’s results provide additional support for the increasing call to target self-regulatory mechanisms in the promotion of school readiness (Blair, 2002; Blair & Diamond, 2008). An important first step is the development and dissemination of assessment tools for children’s selfregulation in the classroom. Such efforts could help identify children with attention deficits who may be at risk for subsequent cognitive and behavior problems. A comprehensive battery tapping the emotional, attentional, and behavioral domains of selfregulation was recently developed and validated for low-income preschoolers (Smith-Donald, Raver, Hayes, & Richardson, 2007). Additional tests for measuring the individual and collective components of self-regulation should be piloted in diverse samples.
A second area for future research concerns sustained attention per se as a potential target for intervention to alleviate poor school performance in low-income children. The results of the current study provisionally support two strategies that might be tested. The first strategy involves the promotion of focused attention, which we find to be associated with cognitive school readiness among all low-income children. The second strategy involves the promotion of impulse control, which we find to be associated with both cognitive and behavioral school readiness but only among children below the poverty threshold. Current efforts directly targeting young children’s attention and other self-regulatory skills have shown great promise (Barnett et al., 2008; Bodrova & Leong, 2007; Diamond, Barnett, Thomas, & Munro, 2007; Rueda, Rothbart, McCandliss, Saccomanno, & Posner, 2005). These and future initiatives to assess and promote sustained attention may prove fruitful at increasing school readiness among low-income children.
This research was supported in part by Eunice Kennedy Shriver National Institute of Child Health and Human Development Grants R01HD36916, R01HD39135, and R01HD40421 and by a consortium of private foundations supporting the Fragile Families and Child Wellbeing Study.
1In the NICHD SECCYD study, which used a continuous performance task to assess attention at 5 years of age (NICHD ECCRN, 2003), the Sustained Attention scale is comparable with our Focused Attention scale, and the Impulsivity scale is comparable with our Lack of Impulsivity scale.
Earlier findings, on which this article is based, were first presented at the Society for Research on Child Development Conference, Denver, Colorado, April 2009.
This article was published Online First August 2, 2010.
Rachel A. Razza, Department of Child and Family Studies, Syracuse University.
Anne Martin, National Center for Children and Families, Teachers College, Columbia University.
Jeanne Brooks-Gunn, National Center for Children and Families, Teachers College and the College of Physicians and Surgeons, Columbia University.