Selective augmentation of striatal functional connectivity following NMDA receptor antagonism: implications for psychosis.

The psychotomimetic effect of the N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine is thought to arise from a functional modulation of the brain's fronto-striato-thalamic (FST) circuits. Animal models suggest a pronounced effect on ventral 'limbic' FST systems, although recent work in patients with psychosis and high-risk individuals suggests specific alterations of dorsal 'associative' FST circuits. Here, we used functional magnetic resonance imaging to investigate the effects of a subanesthetic dose of ketamine on measures of functional connectivity as indexed by the temporal coherence of spontaneous neural activity in both dorsal and ventral FST circuits, as well as their symptom correlates.

Circuit-specific changes in D-serine-dependent activation of the N-methyl-D-aspartate receptor in the aging hippocampus.

Age-related memory deficits have recently been associated with the impaired expression of D-serine-dependent synaptic plasticity in neuronal networks of the hippocampal CA1 area. However, whether such functional alterations are common to the entire hippocampus during aging remains unknown. Here, we found that D-serine was also required for the induction of N-methyl-D-aspartate receptor (NMDA-R)-dependent long-term potentiation (LTP) at perforant path-granule cell synapses of the dentate gyrus.

[Assessment of mental states at risk of psychotic transition: validation of the French version of the CAARMS].

This article aims to present the validation study of the French version of the Comprehensive Assessment of at risk mental states (CAARMS), an interview that seeks to determine whether young adults criteria for at-risk (AR) mental states, or psychosis. We assessed 40 young subjects, 15 were considered as "prodromal" (Prd) and 10 as experiencing a first episode of psychosis (PEP) by our expert clinician at the center - centre d'évaluation des jeunes adultes et adolescents, University Hospital Centre, Paris - and 15 were healthy controls matched for age and sex. When assessed with the CAARMS, 73 % (n=11) of the prodromal subjects reached the criteria for AR mental state, four subjects did not reach the criteria for AR, nor psychosis (P) and 100 % of the PEP reached the criteria for P.

Relationships between Personality Traits, Medial Temporal Lobe Atrophy, and White Matter Lesion in Subjects Suffering from Mild Cognitive Impairment.

Mild cognitive impairment (MCI) is a heterogeneous cognitive status that can be a prodromal stage of Alzheimer's disease (AD). It is particularly relevant to focus on prodromal stages of AD such as MCI, because patho-physiological abnormalities of AD start years before the dementia stage. Medial temporal lobe (MTL) atrophy resulting from AD lesions and cerebrovascular lesions [i.

Effect of genetic and pharmacological blockade of GABA receptors on the 5-HT2C receptor function during stress.

Serotonin (5-HT)2C receptors play a role in psychoaffective disorders and often contribute to the antidepressant and anxiolytic effects of psychotropic drugs. During stress, activation of these receptors exerts a negative feedback on 5-HT release, probably by increasing the activity of GABAergic interneurons. However, to date, the GABA receptor types that mediate the 5-HT2C receptor-induced feedback inhibition are still unknown.

Patient "candidate" for thrombolysis: MRI is essential.

Because of its excellent sensitivity and specificity to diagnose arterial ischemic stroke (AIS) in the acute phase, MRI answers the main questions to guide treatment in "candidates" for thrombolysis. It lasts less than ten minutes, can confirm the diagnosis of AIS and distinguish it from hematomas and other "stroke mimics". It can identify the ischemic penumbra (perfusion-diffusion mismatch), determine the site of occlusion and provide prognostic information to adapt treatment in some cases in which the indications are poorly defined.

Long-term physiological alterations and recovery in a mouse model of separation associated with time-restricted feeding: a tool to study anorexia nervosa related consequences.

Background: Anorexia nervosa is a primary psychiatric disorder, with non-negligible rates of mortality and morbidity. Some of the related alterations could participate in a vicious cycle limiting the recovery. Animal models mimicking various physiological alterations related to anorexia nervosa are necessary to provide better strategies of treatment.

Chronic assessment of cerebral hemodynamics during rat forepaw electrical stimulation using functional ultrasound imaging.

Functional ultrasound imaging is a method recently developed to assess brain activity via hemodynamics in rodents. Doppler ultrasound signals allow the measurement of cerebral blood volume (CBV) and red blood cells' (RBCs') velocity in small vessels. However, this technique originally requires performing a large craniotomy that limits its use to acute experiments only.

An early reduction in GH peak amplitude in preproghrelin-deficient male mice has a minor impact on linear growth.

Ghrelin is a gut hormone processed from the proghrelin peptide acting as the endogenous ligand of the GH secretagogue receptor 1a. The regulatory role of endogenous ghrelin on pulsatile GH secretion and linear growth had to be established. The aim of the present study was to delineate the endogenous actions of preproghrelin on peripheral and central components of the GH axis.

[What future for carotid stenosis management?].

Surgery remains the first choice intervention in patients with severe symptomatic carotid stenosis. Stenting is associated with a higher periprocedural risk of stroke compared with surgery. This excess risk of stroke with stenting mainly concerns patients older than 70years, whereas the risk seems to be similar in patients younger than 70years.

Effects of healthy ageing on activation pattern within the primary motor cortex during movement and motor imagery: an fMRI study.

The increase in older adults over the coming decades will be accompanied by a greater burden of chronic neurological diseases affecting the motor system. The motor system adapts to maintain motor performance with the primary motor cortex (BA4) emerging as a pivotal node within this neuroplastic process. Studies of ageing often consider BA4 a homogenous area but cytoarchitectonic studies have revealed two subdivisions, an anterior (BA4a) and posterior subdivision (BA4p).

Chronic persecutory delusion and autobiographical memories in patients with schizophrenia: a diary study.

Background: While chronic persecutory delusions are typically anchored into patients' everyday life situations, no investigation has ever looked at how situations associated with a feeling of persecution are recorded and later retrieved.

Method: a diary methodology combined with a recognition task involving ten patients with schizophrenia who presented chronic persecutory delusions and ten control participants. Diaries of everyday persecutory events (Pe) and non-persecutory events (nPe) were kept.

Experts bodies, experts minds: How physical and mental training shape the brain.

Skill learning is the improvement in perceptual, cognitive, or motor performance following practice. Expert performance levels can be achieved with well-organized knowledge, using sophisticated and specific mental representations and cognitive processing, applying automatic sequences quickly and efficiently, being able to deal with large amounts of information, and many other challenging task demands and situations that otherwise paralyze the performance of novices. The neural reorganizations that occur with expertise reflect the optimization of the neurocognitive resources to deal with the complex computational load needed to achieve peak performance.

Effects of exercise on mitochondrial function, neuroplasticity and anxio-depressive behavior of mice.

The present study was aimed at analyzing the effects of physical exercise on mitochondrial physiology, anxio-depressive-like behaviors and neuroplasticity in mice. Adult C57BL/6J male mice were isolated in home cages equipped or not with free-running wheels. After 6weeks of exercise, mice were tested in various behavioral paradigms to evaluate anxiety- and depressive-like behaviors.

Neuropsychological features of adult mastocytosis.

In approximately one-third of cases, patients with mastocytosis can display various disabling general and neuropsychological symptoms. General signs may have a major impact on quality of life. Neurologic symptoms are less frequent.

When music tempo affects the temporal congruence between physical practice and motor imagery.

When people listen to music, they hear beat and a metrical structure in the rhythm; these perceived patterns enable coordination with the music. A clear correspondence between the tempo of actual movement (e.g.

[Patterns of alcohol consumption in France and their medical and social consequences as seen through the family circle and friends and general practitioners].

Background: Data on the frequency of high-risk alcohol consumption and its medical and social consequences in the French general population remain fragmented. Therefore, our aim was two-fold: (i) to assess the prevalence of different patterns of alcohol consumption using the AUDIT-C scale, according to two different perspectives, i.e.

[Excessive alcohol consumption: what is the burden on natural caregivers?].

Background: Data on the natural caregivers burdened by the excessive consumption of alcohol by members of the family circle or friends in the general population are lacking. Therefore, our aim was twofold: (i) to assess the burden of individuals with excessive alcohol consumption on natural caregivers and (ii) to examine the factors explaining the association between alcohol consumption and the level of burden.

Method: Data were derived from a national representative survey of the French adult population, conducted in 2013, that involved 1018 participants who had in their close environment a person consuming excessive amounts of alcohol.

[Epidemiologic warnings from studies on alcohol use disorders].

The highest consumption levels of alcohol are found in the developed world, mostly the Northern Hemisphere. After a slight decrease at the beginning of the 1990s, alcohol use in the European Region increased with an average adult per capita consumption amounting to 12.5 litres of pure alcohol per capita for the year 2009.

Brain activity and functional coupling changes associated with self-reference effect during both encoding and retrieval.

Information that is processed with reference to oneself, i.e. Self-Referential Processing (SRP), is generally associated with better remembering compared to information processed in a condition not related to oneself.