*Parental Education, Ethnicity, and Functional Connectivity between Nucleus Accumbens… DOI: http://dx.doi.org/10.5772/intechopen.101335*

#### *Parenting - Challenges of Child Rearing in a Changing Society*

#### **Figure 2.**

*Association between parental education and functional connectivity between the left NAcc and FPN overall and by ethnicity.*

ethnicity, and parental education all show multiplicative effects on NAcc restingstate functional connectivity with the FPN. While we found a stronger correlation between parental education and the resting-state FPN's functional connectivity with the right NAcc in Latino than non-Latino children, parental education showed a weaker association with the same connectivity for the left NAcc. The finding on the right NAcc contrasts with the MDRs, but the finding on the left NAcc supports the MDRs' theory, which shows a weaker association between SES and brain development for marginalized and minority children than White children.

Our first finding is in agreement with other work showing the effects of parental education on brain structure [33], performance in several cognitive domains [82], and mental health problems, such as anxiety and depression [34]. However, most of what we know about SES effects are limited to specific brain regions [74, 83, 84], rather than rsFC. Past research has established a link between parental education and the size and activity of brain structures, such as the NAcc [48], amygdala [34], hippocampus [50], and thalamus [49]. In a study of examining a sample of 283 children and adolescents aged 4–18, higher parental education significantly predicted greater cortical thickness in the right anterior cingulate and left superior frontal gyrus [85]. Among 9475 children from the ABCD study, parental education was associated with reduced within and between sensorimotor network connectivity and increased sensorimotor network connectivity to frontal functional networks [76]. Furthermore, in line with our finding, higher parental education is shown to be linked to the development of frontoparietal connectivity in children [76]. Neurodevelopmental correlates of parental education may mediate why parental education is linked to behaviors [86], executive functions [33], reading ability [87], spatial skills, and inhibitory control [55]. Importantly, however, no studies to our knowledge have examined the associations between parental education and rsFC within the NAcc and FPN.

The effect of parental education on brain function can be explained by underlying mechanisms [88], such as cognitive stimulation available at home, parent–child interactions, and home learning environment, which all predict brain

#### *Parental Education, Ethnicity, and Functional Connectivity between Nucleus Accumbens… DOI: http://dx.doi.org/10.5772/intechopen.101335*

development [33, 88]. For example, more educated parents dedicate more time for their children in ways that seem to improve their children's development [89, 90]. Likewise, more educated parents appear to have higher expectations for their children, provide more stimulating learning materials, use more complex language and speech patterns, and engage more with their children's learning [89, 91]. These can help promote children's cognitive development [90]. Furthermore, the skills obtained from formal education appear to enable parents to arrange their activities in ways that allow them to effectively accomplish their parenting goals [88].

The results of the right NAcc-FPN connectivity were not in line with what is shown from the comparison of Black and White children. According to the MDRs' theory, parental education is more protective for White children than Black children. This finding was observed for the left NAcc-FPN connectivity. Similar to our finding on the left side, the effects of SES on attention [59], reward dependence [61], school performance [60], aggression [64], impulsivity [62], suicide [63], anxiety [92], and problem behaviors [66] are shown to be weaker in Black than White adolescents. This is the first study on the MDRs of parental education for NAcc functional connectivity with the FPN in Latino children. Even when MDRs exist, the right and left NAcc findings may vary largely.

Parental education has different and group-specific effects on children and youth brain development. This means that SES resources and ethnicity may have multiplicative, rather than additive, effects on the right NAcc resting-state functional connectivity with FPN. In this study and all the MDRs' literature, ethnic variation in the SES effects is shaped by social rather than biological mechanisms. Thus, in our study, ethnicity is a social rather than biological factor. Consequently, the differential treatment of society, which is preventable, has resulted in the ethnic differences. Importantly, we consider race as a proxy of racism, such as labor market discrimination, low school quality, segregation, and differential policing, that results in reduced effects of parental education, even for more educated people [93].

## **5. Limitations**

The present study had some limitations. Firstly, a cross-sectional design limits any inference of causal links between parental education, ethnicity, and NAcc functional connectivity with the FPN. Secondly, we only studied parental education; other SES indicators were not included. Moreover, we did not examine how other factors, such as neighborhood context, stress, and social adversities, mitigate these effects across groups. Thirdly, Latino people are highly diverse. Cuban, Mexican, and Puerto Rican families differ in their history, culture, neighborhoods, SES, and other factors that may alter SES effects.

### **6. Conclusions**

Although high NAcc resting-state functional connectivity with FPN is under the influence of parental education, ethnicity, and laterality, these effects are multiplicative rather than additive. This means that, while the parental education gradient was stronger for the right NAcc in Latino than non-Latino American preadolescents, the opposite finding was observed for the left NAcc. Due to qualitative differences in the lived conditions of ethnic groups in the United States, various subgroups may show different SES effects on brain development.
