**2.4 Process**

### *2.4.1 Study variables*

The study variables included parental education (independent variable), children's ethnicity (moderator), ethnicity, age, race, sex, parental marital status (confounders), and NAcc functional connectivity with the FPN, separately calculated for the right and left (dependent variables).

### *2.4.1.1 Independent variables*

*Parental education.* Parental education was considered as a five-level nominal variable: less than high school (HS) diploma, high school (HS) diploma, some college, bachelors' degree, and postgraduate degree.

## *2.4.1.2 Dependent variables*

*Right and left NAcc resting-state functional connectivity with FPN.* Using restingstate fMRI, the NAcc was defined as the average correlation between the FPN and ASEG ROI right-accumbens area. This is the functional connectivity between the FPN and the NAcc. The resting-state fMRI was measured at baseline at the same time that parental education was measured. These results were separately

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

calculated for the right and left NAcc. Our outcomes had normal distributions (Appendix Figure).
