Neural network modelling reveals changes in directional connectivity between cortical and hypothalamic regions with increased BMI.
Int J Obes (Lond)
; 45(11): 2447-2454, 2021 11.
Article
em En
| MEDLINE
| ID: mdl-34341471
ABSTRACT
BACKGROUND/OBJECTIVES:
Obesity has been ascribed to corticostriatal regions taking control over homeostatic areas. To test this assumption, we applied an effective connectivity approach to reveal the direction of information flow between brain regions and the valence of connections (excitatory versus inhibitory) as a function of increased BMI and homeostatic state. SUBJECTS/METHODS:
Forty-one participants (21 overweight/obese) underwent two resting-state fMRI scans after overnight fasting (hunger) and following a standardised meal (satiety). We used spectral dynamic causal modelling to unravel hunger and increased BMI-related changes in directed connectivity between cortical, insular, striatal and hypothalamic regions.RESULTS:
During hunger, as compared to satiety, we found increased excitation of the ventromedial prefrontal cortex over the ventral striatum and hypothalamus, suggesting enhanced top-down modulation compensating energy depletion. Increased BMI was associated with increased excitation of the anterior insula over the hypothalamus across the hunger and satiety conditions. The interaction of hunger and increased BMI yielded decreased intra-cortical excitation from the dorso-lateral to the ventromedial prefrontal cortex.CONCLUSIONS:
Our findings suggest that excess weight and obesity is associated with persistent top-down excitation of the hypothalamus, regardless of homeostatic state, and hunger-related reductions of dorso-lateral to ventromedial prefrontal inputs. These findings are compatible with eating without hunger and reduced self-regulation views of obesity.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Índice de Massa Corporal
/
Córtex Pré-Frontal
/
Hipotálamo
/
Rede Nervosa
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
Int J Obes (Lond)
Assunto da revista:
METABOLISMO
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Austrália