Changing minds: A study of cognitive change disparities and their social determinants among older adults in the health and retirement study, 1998–2012.

Despite the rapidly growing literature on cognitive functioning trajectories, sociologists
and social demographers have been largely removed from the research on age-related cognitive
change. Indeed, research on cognitive decline tends to be dominated by biological psychologists
and cognitive neuroscientists. Given the important insights that the sociological and demographic
perspective can provide to understanding cognitive aging processes—particularly with regards to
the social determinants of cognitive aging and how the patterns of change vary across social
locations (e.g. race, gender, socioeconomic status)—it is imperative for a social demographic
analysis to be applied when examining cognitive aging. This dissertation aims to describe and
explain sociodemographic variations in trajectories of age-related cognitive decline. Using data
from the nationally representative longitudinal Health and Retirement Study (HRS) and drawing
on the life course perspective, reserve theory, intersectionality theory, and differential
exposure/susceptibility perspectives, this study uses an integrated person-centered/variablecentered methodological approach to examine both patterns of cognitive decline across social
locations as well as said patterns’ social determinants. Broadly, this study has three main aims.
First, this study aims to provide a more nuanced understanding of the various trajectories of agerelated cognitive decline by estimating and examining distinct classes of cognitive aging
trajectories using general growth mixture modeling with latent trajectory classes (GGMM-LTC).
Further, this study seeks to ascertain whether the cognitive aging disparities follow an age-asleveler, persistent inequality, or cumulative (dis)advantage pattern. Additionally, I examine
whether active or passive reserve processes underlie changes in cognitive performance with
advancing age. Building on the previous identification of distinct classes of cognitive decline, the
second aim of this study is to examine patterns of cognitive aging across social locations by
applying intersectionality theory. Lastly, the third aim is to employ differential exposure and
differential susceptibility hypotheses to explain racial and gender differences in cognitive aging
patterns. Findings addressing the first aim indicate that distinct classes for both episodic memory
and mental status exist, and that membership in classes is stratified by race, gender, socioeconomic
status, health, and early life adversity. Additionally, support for the age-as leveler, persistent
inequality, and cumulative (dis)advantage patterns were found depending on the groups compared
and the cognitive domain examined. It was also found that the cognitive reserve process plays out
in the mental status domain. Findings related to the second aim of this study indicate that gender
and levels of education influence cognitive trajectory class membership for blacks and whites in
both episodic memory and mental status domains. More specifically, whites and respondents with
higher levels of education are more likely to belong in episodic memory and mental status classes
with higher levels of initial functioning. Further, I find evidence for the multiplicative effects of
gender and education for episodic memory among whites and for mental status among both whites
and blacks thus providing support for the intersectionality perspective. Lastly, findings related to
the third aim show that race and gender are both significant predictors of episodic memory and
mental status trajectory class membership. Blacks and men are more likely to belong in episodic
memory trajectory classes characterized by low initial function with more rapid declines than their
white and female counterparts. For mental status, blacks and women are more likely to be in lower
initial functioning classes, but are advantaged with regards to rate of decline. Additionally,
findings provide little evidence for the notion that early life adversity attenuates the relationship
between race and/or gender and cognitive decline trajectory class membership, thereby no support
for the differential exposure hypothesis was found. Lastly, lack of statistically significant
interactions between both race and gender and early life adversity indicates that there is no support
for the differential susceptibility hypothesis. Overall, findings herein show that the social
patterning and determinants of cognitive decline in the U.S. are complex, varying with the groups
being compared as well as the cognitive domain in question. Moreover, this dissertation provides
an argument that researchers in the area of cognitive decline would benefit greatly from an
intersectionality approach. This dissertation concludes with the placement of current findings
within the existing literature, a detailing of policy implications, a discussion of study limitations,
and the outlining of planned future research in the area of cognitive decline and ideas for better
cognitive functioning assessment in the population.