Effects of Anorexia Nervosa (Neurobiological (Brain Atrophy (Fonville et.…
Effects of Anorexia Nervosa
Brain Atrophy (Fonville et. al, 2014)
Aims of study:
1) Correlate clinical measures with brain tissue volume (whole brain, GMV, ad WMV) in AN.
2) Explore the impact of the age of onset and illness duration on volumetric measures
Participants: 31 individuals with current diagnosis of AN (DSM-IV); 31 healthy controls w/o familial history of AN.
Glial and Neuronal Damage (Ehrlich, et. al, 2008)
Elevated Homocysteine Plasma Levels (Frieling et. al, 2005)
Correlated with brain atrophy
Altered social reward and attention in anorexia nervosa (Watson et. al, 2010)
Spend more time than healthy controls looking at body parts compared to eyes and faces; tendency to avoid eye contact.
The recognition of emotion in the faces and voice of anorexia nervosa (Kucharska-Pietura et. al, 2004)
Poor emotional recognition of negative facial affect.
Impaired recognition of both positive and negative emotion in voices.
Implications: Difficulty recognizing emotions from faces and vocal tone may contribute to poor interpersonal communication and lack of empathy observed in individuals with anorexia.
Perception of affective touch in anorexia nervosa (Crucianelli et. al, 2016)
Individuals with anorexia perceive interpersonal affective touch as less pleasant than healthy controls; indication of dysfunctional CT afferent system.
Evidence for tactile anhedonia (reduced subjective perception of pleasure) in anorexia nervous.
CT-based affective touch system may be implicated in body distortion in AN; Affective touch has been shown to contribute uniquely to the multisensory integration processes that underlie the subjective sense of body ownership in which anorexic individuals tend to lack.
Response to disorder-related stimuli
Voluntary emotion regulation in anorexia nervosa: A preliminary emotion-modulated startle investigation. (Racine et. al, 2016)
Enhanced emotional reactivity and startle response to images of food; in contrast, healthy controls seem exhibit startle inhibition when looking at images of food.
Food appears to activate the defensive motivational system in a manner similar to aversive stimuli in women with AN.
May shed light on how individuals with AN process food stimuli.
“Glass fairies” and “bone children”: Adolescents and young adultswith anorexia nervosa show positive reactions towards extremelyemaciated body pictures measured by the startle reflex paradigm (Reichel et. al, 2014)
Images of extremely emaciated bodies (in analogy to addictive cues in addiction disorders) evoke appetitive responses in individuals with AN; effect was not found in mainstream magazine photos
In contrast, images of emaciated bodies evoked aversive responses in healthy controls
Indicates that individuals with AN strive for a very extreme type of thinness beyond what is often idealized in mass media; drawn to images on pro ana websites.
-restriction of required energy intake
-intense fear of gaining weight or becoming fat
-disturbance is self-perceived weight or shape
-abnormally low body weight
(American Psychiatric Association, 2013)