The effects of acute tryptophan depletion on instrumental reward learning in anorexia nervosa – an fMRI study

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung


BACKGROUND: The serotonin (5-HT) hypothesis of anorexia nervosa (AN) posits that individuals predisposed toward or recovered from AN (recAN) have a central nervous hyperserotonergic state and therefore restrict food intake as a means to reduce 5-HT availability (via diminished tryptophan-derived precursor supply) and alleviate associated negative mood states. Importantly, the 5-HT system has also been generally implicated in reward processing, which has also been shown to be altered in AN.

METHODS: In this double-blind crossover study, 22 individuals recAN and 25 healthy control participants (HC) underwent functional magnetic resonance imaging (fMRI) while performing an established instrumental reward learning paradigm during acute tryptophan depletion (ATD; a dietary intervention that lowers central nervous 5-HT availability) as well as a sham depletion.

RESULTS: On a behavioral level, the main effects of reward and ATD were evident, but no group differences were found. fMRI analyses revealed a group × ATD × reward level interaction in the ventral anterior insula during reward anticipation as well as in the medial orbitofrontal cortex during reward consumption.

DISCUSSION: The precise pattern of results is suggestive of a 'normalization' of reward-related neural responses during ATD in recAN compared to HC. Our results lend further evidence to the 5-HT hypothesis of AN. Decreasing central nervous 5-HT synthesis and availability during ATD and possibly also by dieting may be a means to normalize 5-HT availability and associated brain processes.


Seiten (von - bis)3426-3436
FachzeitschriftPsychological medicine
PublikationsstatusVeröffentlicht - 28 Juni 2023

Externe IDs

Scopus 85128326405
unpaywall 10.1017/s0033291721005493
WOS 000773737800001
ORCID /0000-0002-2864-5578/work/142233468
ORCID /0000-0003-2132-4445/work/142236336
PubMed 35343412
PubMedCentral PMC10277771
ORCID /0000-0001-5398-5569/work/150329459


Ziele für nachhaltige Entwicklung


  • Anorexia nervosa, acute tryptophan depletion, fMRI, reward, serotonin, Cross-Over Studies, Magnetic Resonance Imaging, Serotonin, Humans, Tryptophan, Anorexia Nervosa/diagnostic imaging, Reward