Investigating interoceptive abilities in Eating Disorders

Interoception refers to the sense of change in internal states within the body. This can include a wide
range of sensations, from being aware of one's own heartbeat, to experiencing feelings of hunger or
thirst. Individual differences in interoception have been proposed to underlie a variety of psychiatric
disorders, including depression and anxiety, as well as psychological processes such as decision making,
empathy and memory. Recently, it has been proposed that interoception may play a role in the
development of eating disorders. Specifically, atypical processing of interoceptive signals could lead to
disruption in the ability to detect cues of hunger and satiety. Furthermore, given evidence that atypical
interoception may contribute to difficulties in emotional regulation and awareness, factors which have
also been implicated in eating disorders, it is possible that altered interoceptive processing may lead to
development of emotional disturbances for which individuals use disordered eating behaviour as a
coping mechanism. Despite the promising possibility that interoception may be an important, yet
understudied, factor in eating disorders, it is vital to consider some of the methodological issues which
have recently been raised. The most common way of measuring individual differences in interoceptive
ability is via the heartbeat tracking task (HTT), which is a measure of cardiac interoceptive accuracy.
Previous research has predominantly used cardiac interoception using the HTT as a measure of general
interoceptive ability. However, there is debate as to whether interoception is unitary and can be
measured using a single test, or whether it is a fractionated construct that is dependent on the
interoceptive domain being tested. This project aims to improve understanding of the contribution of
interoception to eating disorder development using a wider range of methodological tests than in
previous research. Using five tasks measuring cardiac, respiratory, taste, muscular, and gastric
interoception, the project will begin by examining interoceptive differences between healthy adult control
participants and individuals with a clinical diagnosis of an eating disorder. As adolescence is thought to
be a critical period in eating disorder development, and a period during which interoceptive abilities often
decrease, the project will further examine the development of interoception and eating disorder
symptoms in a second, cross sectional study across three age groups (10, 11.5, and 13 years).
Furthermore, two longitudinal studies have been planned. The first will follow the youngest age group
from study two and assess change in interoceptive ability after 18 months. The second will assess
change over 18 months in a group of children at-risk of developing an eating disorder, and a non-at-risk
group, with risk determined by a variety of factors such as familial presence of an eating disorder and
personality factors. This will enable exploration of whether atypical interoception at time one is predictive
of body dissatisfaction and eating disordered symptoms at time two, as well as assessing how
interoceptive ability interacts with additional risk factors. The results of this research will not only
contribute to the current methodological debate regarding the validity of unitary measurement in
interoceptive research, but will also provide valuable insight into the development of interoception and
eating disorder symptoms in adolescence. If atypical interoception is a significant contributor to eating
disorders, either directly by producing dysfunction in hunger and satiety cues, or indirectly by
contributing to emotional difficulties, then it is essential that future treatments are developed which
directly address this issue.