On the relationship between the “default mode network” and the “social brain”

The default mode network (DMN) of the brain consists of areas that are typically more active during rest than during active task performance. Recently however, this network has been shown to be activated by certain types of tasks. Social cognition, particularly higher-order tasks such as attributing mental states to others, has been suggested to activate a network of areas at least partly overlapping with the DMN. Here, we explore this claim, drawing on evidence from meta-analyses of functional MRI data and recent studies investigating the structural and functional connectivity of the social brain. In addition, we discuss recent evidence for the existence of a DMN in non-human primates. We conclude by discussing some of the implications of these observations

Manipulation of subcortical and deep cortical activity in the primate brain using transcranial focused ultrasound stimulation

Publisher’s embargo period: Embargo set on 04.03.2019 by SR (TIS).The causal role of an area within a neural network can be determined by interfering with its activity and measuring the impact. Many current reversible manipulation techniques have limitations preventing their application, particularly in deep areas of the primate brain. Here, we demonstrate that a focused transcranial ultrasound stimulation (TUS) protocol impacts activity even in deep brain areas: a subcortical brain structure, the amygdala (experiment 1), and a deep cortical region, the anterior cingulate cortex (ACC, experiment 2), in macaques. TUS neuromodulatory effects were measured by examining relationships between activity in each area and the rest of the brain using functional magnetic resonance imaging (fMRI). In control conditions without sonication, activity in a given area is related to activity in interconnected regions, but such relationships are reduced after sonication, specifically for the targeted areas. Dissociable and focal effects on neural activity could not be explained by auditory confounds

An Open Resource for Non-human Primate Imaging.

Non-human primate neuroimaging is a rapidly growing area of research that promises to transform and scale translational and cross-species comparative neuroscience. Unfortunately, the technological and methodological advances of the past two decades have outpaced the accrual of data, which is particularly challenging given the relatively few centers that have the necessary facilities and capabilities. The PRIMatE Data Exchange (PRIME-DE) addresses this challenge by aggregating independently acquired non-human primate magnetic resonance imaging (MRI) datasets and openly sharing them via the International Neuroimaging Data-sharing Initiative (INDI). Here, we present the rationale, design, and procedures for the PRIME-DE consortium, as well as the initial release, consisting of 25 independent data collections aggregated across 22 sites (total = 217 non-human primates). We also outline the unique pitfalls and challenges that should be considered in the analysis of non-human primate MRI datasets, including providing automated quality assessment of the contributed datasets

Cognitive Neuroscience: Acting on Numbers

AbstractThe parietal cortex is a central part of the brain's system for representing numbers and magnitudes. Activity in the parietal cortex might reflect number representation or actions made in response to the numbers

Neural Mechanisms of Suboptimal Decisions

Making good decisions and adapting flexibly to environmental change are critical to the survival of animals. In this thesis, I investigated neural mechanisms underlying suboptimal decision making in humans and underlying behavioural adaptation in monkeys with the use of functional magnetic resonance imaging (fMRI) in both species. In recent decades, in the neuroscience of decision making, there has been a prominent focus on binary decisions. Whether the presence of an additional third option could have an impact on behaviour and neural signals has been largely overlooked. I designed an experiment in which decisions were made between two options in the presence of a third option. A biophysical model simulation made surprising predictions that more suboptimal decisions were made in the presence of a very poor third alternative. Subsequent human behavioural testing showed consistent results with these predictions. In the ventromedial prefrontal cortex (vmPFC), I found that a value comparison signal that is critical for decision making became weaker in the presence of a poor value third option. The effect contrasts with another prominent potential mechanism during multi-alternative decision making – divisive normalization – the signatures of which were observed in the posterior parietal cortex. It has long been thought that the orbitofrontal cortex (OFC) and amygdala mediate reward-guided behavioural adaptation. However, this viewpoint has been recently challenged. I recorded whole brain activity in macaques using fMRI while they performed an object discrimination reversal task over multiple testing sessions. I identified a lateral OFC (lOFC) region in which activity predicted adaptive win-stay/lose-shift behaviour. In contrast, anterior cingulate cortex (ACC) activity predicted future exploratory decisions regardless of reward outcome. Amygdala and lOFC activity was more strongly coupled for adaptive choice shifting and decoupled for task irrelevant reward memory. Day-to-day fluctuations in signals and signal coupling were correlated with day-to-day fluctuations in performance. These data demonstrate OFC, ACC, and amygdala each make unique contributions to flexible behaviour and credit assignment.This thesis is not currently available on ORA

La maison d'arrêt de Briey : détenus politiques par Fanny Lebigot

Photo Ministère de la Justice Située en ville à 80km de Nancy, dans les hauts de Briey, la prison a été construite en 1906. Elle a été une maison d’arrêt jusqu’en 1974 puis un Quartier de Haute Sécurité (QHS) jusqu’en 1982 (date de fermeture de ce type d’établissement). Par la suite, elle redevient maison d’arrêt. Depuis 1990, l’établissement fait office de Centre de Semi-Liberté. En 1996, sa capacité d’accueil est passée de 15 à 25 personnes. Enfin depuis 2004, le CSL est habilité pour écrou..

Contrasting effects of medial and lateral orbitofrontal cortex lesions on credit assignment and decision making in humans

The orbitofrontal cortex is critical for goal-directed behavior. Recent work in macaques has suggested the lateral orbitofrontal cortex (lOFC) is relatively more concerned with assignment of credit for rewards to particular choices during value-guided learning, whereas the medial orbitofrontal cortex (often referred to as ventromedial prefrontal cortex in humans; vmPFC/mOFC) is involved in constraining the decision to the relevant options. We examined whether people with damage restricted to subregions of prefrontal cortex showed the patterns of impairment observed in prior investigations of the effects of lesions to homologous regions in macaques. Groups of patients with either lOFC (predominantly right hemisphere), mOFC/vmPFC, or dorsomedial prefrontal (DMF), and a comparison group of healthy age- and education-matched controls performed a probabilistic 3-choice decision-making task. We report anatomically specific patterns of impairment. We found that credit assignment, as indexed by the normal influence of contingent relationships between choice and reward, is reduced in lOFC patients compared with Controls and mOFC/vmPFC patients. Moreover, the effects of reward contingency on choice were similar for patients with lesions in DMF or mOFC/vmPFC, compared with Controls. By contrast, mOFC/vmPFC-lesioned patients made more stochastic choices than Controls when the decision was framed by valuable distracting alternatives, suggesting that value comparisons were no longer independent of irrelevant options. Once again, there was evidence of regional specialization: patients with lOFC lesions were unimpaired relative to Controls. As in macaques, human lOFC and mOFC/vmPFC are necessary for contingent learning and value-guided decision-making, respectively

Self-Other Mergence in the Frontal Cortex during Cooperation and Competition.

To survive, humans must estimate their own ability and the abilities of others. We found that, although people estimated their abilities on the basis of their own performance in a rational manner, their estimates of themselves were partly merged with the performance of others. Reciprocally, their ability estimates for others also reflected their own, as well as the others', performance. Self-other mergence operated in a context-dependent manner: interacting with high or low performers, respectively, enhanced and diminished own ability estimates in cooperative contexts, but the opposite occurred in competitive contexts. Self-other mergence not only influenced subjective evaluations, it also affected how people subsequently objectively adjusted their performance. Perigenual anterior cingulate cortex tracked one's own performance. Dorsomedial frontal area 9 tracked others' performances, but also integrated contextual and self-related information. Self-other mergence increased with the strength of self and other representations in area 9, suggesting it carries interdependent representations of self and other