Pilot randomized trial demonstrating reversal of obesity-related abnormalities in reward system responsivity to food cues with a behavioral intervention.

OBJECTIVES: Obesity is associated with hyperactivation of the reward system for high-calorie (HC) versus low-calorie (LC) food cues, which encourages unhealthy food selection and overeating. However, the extent to which this hyperactivation can be reversed is uncertain, and to date there has been no demonstration of changes by behavioral intervention. SUBJECTS AND METHODS: We used functional magnetic resonance imaging to measure changes in activation of the striatum for food images at baseline and 6 months in a pilot study of 13 overweight or obese adults randomized to a control group or a novel weight-loss intervention. RESULTS: Compared to controls, intervention participants achieved significant weight loss (-6.3±1.0 kg versus +2.1±1.1 kg, P<0.001) and had increased activation for LC food images with a composition consistent with that recommended in the behavioral intervention at 6 months versus baseline in the right ventral putamen (P=0.04), decreased activation for HC images of typically consumed foods in the left dorsal putamen (P=0.01). There was also a large significant shift in relative activation favoring LC versus HC foods in both regions (P<0.04). CONCLUSIONS: This study provides the first demonstration of a positive shift in activation of the reward system toward healthy versus unhealthy food cues in a behavioral intervention, suggesting new avenues to enhance behavioral treatments of obesity.

Progressive hydrocephalus in infants with birth weights less than 1,500 g.

Premature infants have been frequently observed to manifest hydrocephalus after intraventricular hemorrhage (IVH). For the complete newborn population of Nova Scotia in 1976 to 1978, we found a very low incidence of hydrocephalus in children whose birth weight was less than 1,500 g. Eighty-two percent of these babies were born in a perinatal center; 18% were transported. Chart review of survivors (58%) and autopsy review of deaths (autopsy rate, 86%) showed that in the province's three neonatal intensive care units, only four of 314 such babies manifested progressive hydrocephalus. Only one of four infants was examined after IVH. An IVH was noted at autopsy in 42% of cases. No survivor manifested hydrocephalus one to three years later as judged by head circumference and neurosurgical records. Our results may reflect the impact of regionalized perinatal care, or that post-IVH hydrocephalus is rare in an unselected population.