Neural substrates of parallel devaluation-sensitive and devaluation-insensitive Pavlovian learning in humans.

We aim to differentiate the brain regions involved in the learning and encoding of Pavlovian associations sensitive to changes in outcome value from those that are not sensitive to such changes by combining a learning task with outcome devaluation, eye-tracking, and functional magnetic resonance imaging in humans. Contrary to theoretical expectation, voxels correlating with reward prediction errors in the ventral striatum and subgenual cingulate appear to be sensitive to devaluation. Moreover, regions encoding state prediction errors appear to be devaluation insensitive.

Neural substrates of parallel devaluation-sensitive and devaluation-insensitive Pavlovian learning in humans.

Pavlovian learning depends on multiple and parallel associations leading to distinct classes of conditioned responses that vary in their flexibility following changes in the value of an associated outcome. Here, we aimed to differentiate brain areas involved in learning and encoding associations that are sensitive to changes in the value of an outcome from those that are not sensitive to such changes. To address this question, we combined a Pavlovian learning task with outcome devaluation, eye-tracking and functional magnetic resonance imaging.

Metatarsus adductus setting in adult patients: Results of a treatment algorithm with shortening arthrodesis tarsometatarsal joints two and three.

Background: This study proposes a treatment algorithm based on the correction of symptomatic metatarsus adductus (MA) associated with hallux abducto-valgo (HAV) through tarsometatarsal joint 2-3 (TMTJ) shortening arthrodesis. Our hypothesis is that the proposed algorithm leads to realignment of the forefoot rays from two to five and reduction of the talonavicular coverage angle (TNCA) with good clinical and radiographic results.

Methods: Clinical and radiographic evaluations were performed before and after surgery at 1-year follow-up on forty-six consecutive adult patients with MA, midfoot pain, HAV and osteoarthritis and/or instability of the TMTJ 2-3 in whom shortening of the 2nd and 3rd TMT joints according to MAA and treatment of the HV according to deformity was undertaken.

Mesolimbic Neurobehavioral Mechanisms of Reward Motivation in Anorexia Nervosa: A Multimodal Imaging Study.

Diminished motivation to pursue and obtain primary and secondary rewards has been demonstrated in anorexia nervosa (AN). However, the neurobehavioral mechanisms underlying the behavioral activation component of aberrant reward motivation remains incompletely understood. This work aims to explore this underexplored facet of reward motivation in AN.

White matter tracts characteristics in habitual decision-making circuit underlie ritual behaviors in anorexia nervosa.

Anorexia nervosa (AN) is a difficult to treat, pernicious psychiatric disorder that has been linked to decision-making abnormalities. We examined the structural characteristics of habitual and goal-directed decision-making circuits and their connecting white matter tracts in 32 AN and 43 healthy controls across two independent data sets of adults and adolescents as an explanatory sub-study. Total bilateral premotor/supplementary motor area-putamen tracts in the habit circuit had a significantly higher volume in adults with AN, relative to controls.