Beyond Volitional Resistance: How Starvation Rewires the Brain and Maintains Anosognosia in Anorexia Nervosa

By Vedika Kulshreshtha

Anorexia nervosa is one of the deadliest mental illnesses, with the highest mortality rate of

any psychiatric disorder. At it’s core, the disorder is starvation that strips ones body of the

nutrients critical to survival and growth. Despite being a psychological disorder, it’s

physiological consequences are much more dire, making early intervention and proper

medical attention a priority.

Adolescents and pre-teens are at the highest risk of developing AN (Anorexia nervosa), as

at their fallible age, their brains are malleable and vulnerable to social media’s toxic,

disorder promoting constructs on body image. Paradoxically, this age is when proper

nutrition is critical for physical and cognitive development. Early nutrition deprivation can

result in irreversible physiological abnormalities, as the body—in a chronic calorie deficit—

forces itself into conservation mode. This can lead to countless symptoms:

Loss of subcutaneous fat tissue, severe hair loss, hypothermia, impaired menstrual

function (amenorrhea), orthostatic hypotension and bradycardia, anemia, leukopenia,

fluid-electrolyte imbalances.

However treatment is far from simple in every aspect. It requires for an individual to first

recognize and express a true desire to change their disordered patterns. This is further

made harder by society and closed ones who misinterpret treatment resistance as vanity

and rebellion. They may even internalize this behaviour as neglect and carelessness, and

feel as though the individual does not deem them worthy enough to recover for, when it is

far from that. A lesser known side of AN is anosognosia. It’s a condition wherein an

individual fails to recognize their illness, and in anorexics, it manifests in the form of a

persistent denial of treatment or intervention and a true belief of their distorted self image.

Anosognosia stems from severe interoception deficits, wherein one lacks the ability to

process internal bodily cues.

AN patients have altered their neural pathways.

Normally, satiation is driven by neurological signals from the hypothalamus to the ventral

striatum, however in an anorexic, it flows in reverse—from the ventral striatum to the

hypothalamus. This neural flow mirrors that of a fear response, driving aversive tendencies

surrounding food, and satiety. This occurs as the repetitive association of food with a

negative emotional valence initiates the amygdala to create ‘biased priors’, which in

essence are assumptions constructed to predict outcomes/events. These priors ovveride a

normal physiological response to hunger by suppressing hunger pathways. This leads to a

biological adaptation to restriction, far surpassing the commonly known psychological

aspect of an eating disorder.

Furthermore, research has shown cognitive decline occurrences in individuals with AN.

Neuroimaging depicted significant structural alterations, including reduced overall brain

volume and decreased grey matter concentrations. Grey matter consists of neuronal cell

bodies and is the structural foundation of emotion regulation, problem solving and general

well being. Volume reduction has particularly been noted in the cerebellum, leading to

cerebellar atrophy—the loss or neurons and tissue shrinkage—that disrupts cognitive

processing and affective regulation, contributing directly to the maintenance of a low body

weight and cognitive rigidity. This renders them neurologically resistant to therapeutic

interventions until nutritional rehabilitation.

In conclusion, Anorexia nervosa is not a lifestyle choice, a conscious refusal to seek help

or a display of vanity. It is a severe neurobiological and physiological crisis that rewires

neural circuitry, degrades gray matter, and impairs the brain’s ability to recognize it’s own

state and survival needs. Understanding concepts like anosognosia, interoceptive failure,

frontostriatal dysregulation is critical to dismantling public stigma surrounding treatment

resistance, as it is not a personal obstinacy but rather a starvation-driven cognitive impact.

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