Nucleus accumbens volume mediates the association between prenatal adversity and attention problems in youth

Abstract

Exposure to adversity during the perinatal period has been associated with cognitive difficulties in children. Given the role of the nucleus accumbens (NAcc) in attention and impulsivity, we examined whether NAcc volume at age six mediates the relations between pre- and postnatal adversity and subsequent attention problems in offspring. 306 pregnant women were recruited as part of the Growing Up in Singapore Towards Healthy Outcomes Study. Psychosocial stress was assessed during pregnancy and across the first 5 years postpartum. At six years of age, children underwent structural MRI and, at age seven years, mothers reported on their children's attention problems. Separate factor analyses conducted on measures of pre- and postnatal adversity each yielded two latent factors: maternal mental health and socioeconomic status. Both pre- and postnatal maternal mental health predicted children's attention difficulties. Further, NAcc volume mediated the relation between prenatal, but not postnatal, maternal mental health and children's attention problems. These findings suggest that the NAcc is particularly vulnerable to prenatal maternal mental health challenges and contributes to offspring attention problems. Characterizing the temporal sensitivity of neurobiological structures to adversity will help to elucidate mechanisms linking environmental exposures and behavior, facilitating the development of neuroscience-informed interventions for childhood difficulties.

Keywords: adversity; attention; maternal mental health; nucleus accumbens; perinatal.

Figure 1.. Factor Analyses: Scree Plots

Note: Scree plots of prenatal and postnatal latent factors. The two prenatal and postnatal factors with eigenvalues >1 were retained.

Figure 2.. Pre & Postnatal Adversity and Attention Problems

Note: Association between pre- and postnatal latent factors of adversity and offspring attention problems at year 7; Prenatal MMH = prenatal Maternal Mental Health; Prenatal SES = prenatal Socioeconomic Status; Postnatal MMH = postnatal Maternal Mental Health; Postnatal SES = postnatal Socioeconomic Status.

Figure 3.. NAcc Volume Mediates the Relation between Prenatal Maternal Mental Health and Attention Problems

Note: (a) Indirect effect of prenatal Maternal Mental Health on attention problems through NAcc volume; (b) NAcc volumes plotted across the pre- and postnatal periods by high (+1SD) and low (−1SD) levels of Maternal Mental Health-related stress; c = direct effect; c’ = direct effect after accounting for mediator; NAcc = Nucleus accumbens; Y7 = age 7 years; CBCL Attention Problems = attention problems subscale of the Child Behavior Checklist; * indicates p<.05, ** indicates p<.01, *** indicates p<.001; ns indicates non-significant; SD = standard deviation.