Pathways from Birth Weight to ADHD Symptoms through Fluid Reasoning in Youth with or without Intellectual Disability

Although individual differences in fluid reasoning reliably mediate predictions of attention-deficit/hyperactivity disorder (ADHD) symptoms from birth weight in youth with typical cognitive development (TD), it is unknown if this indirect effect operates similarly in the development of ADHD symptoms secondary to intellectual disability (ID). Thus, we evaluated mediation by fluid reasoning in a longitudinal sample of 163 youth (45% female) with (n = 52) or without (n = 111) ID who were followed prospectively from age 5 to age 13. At age 9, youth completed the Arithmetic subtest of the Wechsler Intelligence Scale for Children, a measure of fluid reasoning. At ages 9 and 13, mothers and teachers separately rated youth ADHD symptoms and mothers completed a diagnostic interview. Mediation was tested via path analysis with bootstrapped confidence intervals, and moderated mediation estimated whether indirect effects differed between ID and TD youth or based on youth IQ. Controlling for demographic factors and age 9 ADHD symptoms, age 9 Arithmetic mediated birth weight and multi-method/informant age 13 ADHD symptoms, such that birth weight positively predicted Arithmetic, which negatively predicted ADHD symptoms. Neither ID status nor IQ moderated the observed indirect effect through Arithmetic, suggesting that it was similar for ID and TD youth as well as across the range of youth IQs. These findings support previous evidence that fluid reasoning, as measured by Arithmetic, may causally mediate birth weight and ADHD symptoms, and suggest that this pathway operates similarly with respect to the development of ADHD symptoms in youth with ID.     

Mediated pathways from maternal depression and early parenting to children's executive function and externalizing behaviour problems

Structural equation models were used to examine pathways from maternal depression and early parenting to children's executive function (EF) and externalizing behaviours in the first nationally representative study to obtain direct assessments of children's kindergarten EF skills (i.e., the Early Childhood Longitudinal Study Kindergarten Class of 2010–2011). Preliminary analyses revealed that maternal depression was negatively related to children's EF and positively related to children's externalizing behaviour problems. However, the negative association between maternal depression and children's EF was completely mediated by maternal parenting practices (i.e., warmth and home learning stimulation). Furthermore, there was an indirect effect from maternal parenting practices to children's externalizing behaviour problems through EF, such that children with stronger EF skills had fewer externalizing behaviour problems. Findings provide support for a family process model in which warm, cognitively stimulating parenting supports children's EF, which in turn decreases externalizing behaviours.

Highlights

• This study examined pathways from parent mental health to children's executive function (EF) and behaviour problems.
• Maternal depression was negatively related to children's EF and positively related to children's behaviour problems.
• The negative association between maternal depression and children's EF was completely mediated by maternal parenting. There was an indirect effect from maternal parenting to children's behaviour problems through EF.

     

Multisensory information boosts numerical matching abilities in young children

This study presents the first evidence that preschool children perform more accurately in a numerical matching task when given multisensory rather than unisensory information about number. Three- to 5-year-old children learned to play a numerical matching game on a touchscreen computer, which asked them to match a sample numerosity with a numerically equivalent choice numerosity. Samples consisted of a series of visual squares on some trials, a series of auditory tones on other trials, and synchronized squares and tones on still other trials. Children performed at chance on this matching task when provided with either type of unisensory sample, but improved significantly when provided with multisensory samples. There was no speed–accuracy tradeoff between unisensory and multisensory trial types. Thus, these findings suggest that intersensory redundancy may improve young children’s abilities to match numerosities.     

The face of an angel: Effect of exposure to details of moral behavior on facial recognition memory

The Dangerous Decisions Theory (DDT; Porter & ten Brinke, 2009) posits that instantaneous perceptions of trustworthiness based on a stranger's face influence the manner in which ensuing information about the target is processed. This study tested a bi-directional DDT model, proposing that information concerning a target's moral behavior could distort eyewitness memory for the individual's facial trustworthiness. Participants (N = 141) viewed a target individual's face (previously rated as appearing “neutral” on trustworthiness) and then were exposed to one of the three vignettes describing the target's behavior (either immoral, morally neutral, or altruistic). Following a delay, observers were asked to identify the target individual on a facial morph video (continuously ranging in levels of perceived trustworthiness). Results indicated that behavioral information varying in morality influenced facial recognition memory; specifically, faces were recalled as having less trustworthy features following a disclosure of immoral/criminal behavior.