The the current income of the participant as

The purpose of the article written by Kim and others in
2013, was to examine the impact of childhood poverty on adult amygdala and
prefrontal cortex brain activity.  The
amygdala and ventrolateral, dorsolateral, and medial prefrontal cortex were
examined due to their association in the processing of emotions.  The amygdala is involved in the emotional response
of the individual, while the prefrontal cortex has been found to act as a regulator
of the amygdala.  The study was conducted
by recording the participant’s family income level at the age of nine and then
determining their response to negative images at the age of twenty-four using
functional magnetic resonance imaging (fMRI).  Additionally, the authors also examined the
level of stress the participant experienced from the ages of nine to seventeen.  The results of this study revealed that participants
who grew up in a low-income household showed decreased dorsolateral and
ventrolateral prefrontal cortex activity as young adults.  However, the activity in the amygdala for
these individuals was increased.  The
authors reported that the current income of the participant as an adult did not
alter these results.  Stress experienced
by the participant through the ages of nine to seventeen was determined by the
researchers to function as a mediator, bridging the gap between childhood
poverty and modified adult brain activity. 
The authors also reported that participants who grew up in a high-income
household were found to have increased activity in the ventrolateral prefrontal
cortex at the age of twenty-four compared to those who grew up in a low-income
household.  Additional brain structures
that the authors reported as showing decreased activity levels due to growing
up in a low-income household include the precentral gyrus and the superior
temporal gyrus.  The authors conclude by
stating that the results of their study suggest that the ability to regulate
emotions as a young adult can be affected by family income status as a child,
and that this association is mediated by chronic stress experienced throughout
childhood.