Search results for "FRONTAL CORTEX"
showing 10 items of 355 documents
Measuring spectrally-resolved information transfer.
2020
Information transfer, measured by transfer entropy, is a key component of distributed computation. It is therefore important to understand the pattern of information transfer in order to unravel the distributed computational algorithms of a system. Since in many natural systems distributed computation is thought to rely on rhythmic processes a frequency resolved measure of information transfer is highly desirable. Here, we present a novel algorithm, and its efficient implementation, to identify separately frequencies sending and receiving information in a network. Our approach relies on the invertible maximum overlap discrete wavelet transform (MODWT) for the creation of surrogate data in t…
A specific prelimbic-nucleus accumbens pathway controls resilience versus vulnerability to food addiction
2019
Food addiction is linked to obesity and eating disorders and is characterized by a loss of behavioral control and compulsive food intake. Here, using a food addiction mouse model, we report that the lack of cannabinoid type-1 receptor in dorsal telencephalic glutamatergic neurons prevents the development of food addiction-like behavior, which is associated with enhanced synaptic excitatory transmission in the medial prefrontal cortex (mPFC) and in the nucleus accumbens (NAc). In contrast, chemogenetic inhibition of neuronal activity in the mPFC-NAc pathway induces compulsive food seeking. Transcriptomic analysis and genetic manipulation identified that increased dopamine D2 receptor express…
Polysialic Acid Acute Depletion Induces Structural Plasticity in Interneurons and Impairs the Excitation/Inhibition Balance in Medial Prefrontal Cort…
2016
The structure and function of the medial prefrontal cortex (mPFC) is affected in several neuropsychiatric disorders, including schizophrenia and major depression. Recent studies suggest that imbalances between excitatory and inhibitory activity (E/I) may be responsible for this cortical dysfunction and, therefore, may underlie the core symptoms of these diseases. This E/I imbalance seems to be correlated with alterations in the plasticity of interneurons but there is still scarce information on the mechanisms that may link these phenomena. The polysialylated form of the neural cell adhesion molecule (PSA-NCAM) is a good candidate, because it modulates the neuronal plasticity of interneurons…
Chronic Stress Modulates Interneuronal Plasticity: Effects on PSA-NCAM and Perineuronal Nets in Cortical and Extracortical Regions.
2018
Chronic stress has an important impact on the adult brain. However, most of the knowledge on its effects is focused on principal neurons and less on inhibitory neurons. Consequently, recent reports have begun to describe stress-induced alterations in the structure, connectivity and neurochemistry of interneurons. Some of these changes appear to be mediated by certain molecules particularly associated to interneurons, such as the polysialylated form of the neural cell adhesion molecule (PSA-NCAM) and components of the perineuronal nets (PNN), specialized regions of the extracellular matrix. These plasticity-related molecules modulate interneuronal structure and connectivity, particularly of …
Modulation of brain PUFA content in different experimental models of mice.
2016
International audience; The relative amounts of arachidonic acid (AA) and docosahexaenoic acid (DHA) govern the different functions of the brain. Their brain levels depend on structures considered, on fatty acid dietary supply and the age of animals. To have a better overview of the different models available in the literature we here compared the brain fatty acid composition in various mice models (C57BL/6J, CD1, Fat-1, SAMP8 mice) fed with different n-3 PUFA diets (deficient, balanced, enriched) in adults and aged animals. Our results demonstrated that brain AA and DHA content is 1) structure-dependent; 2) strain-specific; 3) differently affected by dietary approaches when compared to gen…
Blockade of nitric oxide signalling promotes resilience to the effects of social defeat stress on the conditioned rewarding properties of MDMA in mice
2020
Abstract MDMA abuse continues being a serious problem in our society. Environmental factors, such as stress, increase the vulnerability of individuals to develop drug abuse and we have observed that exposure to social defeat (SD) stress alters the sensitivity of mice to the rewarding effects of MDMA in the conditioned place preference (CPP) paradigm. In the present study, we evaluated the role of the nitric oxide (NO) pathway in the effects of SD on the rewarding properties of MDMA. Three groups of mice were treated with an inhibitor of NO synthesis, 7-nitroindazole (0, 7.25 and 12.5 mg/kg), before each exposure to SD and place conditioning with MDMA (1.25 mg/kg) on PND 54, 56, 58, and 60. …
Differential role of interleukin-1β in neuroinflammation-induced impairment of spatial and nonspatial memory in hyperammonemic rats.
2019
Activated microglia and increased brain IL-1β play a main role in cognitive impairment in much pathology. We studied the role of IL-1β in neuroinflammation-induced impairment of the following different types of learning and memory: novel object recognition (NOR), novel object location (NOL), spatial learning, reference memory (RM), and working memory (WM). All these processes are impaired in hyperammonemic rats. We assessed which of these types of learning and memory are restored by blocking the IL-1 receptor in vivo in hyperammonemic rats and the possible mechanisms involved. Blocking the IL-1 receptor reversed microglial activation in the hippocampus, perirhinal cortex, and prefrontal cor…
Characterizing the Molecular Architecture of Cortical Regions Associated with High Educational Attainment in Older Individuals
2019
Neuroimaging investigations have revealed interindividual variations in anatomy, metabolism, activity, and connectivity of specific cortical association areas through which years of education (YoE), as a common proxy of cognitive reserve, may operate in the face of age- or pathology-associated brain changes. However, the associated molecular properties of YoE-related brain regions and the biological pathways involved remain poorly understood. In the present study we first identified brain areas that showed an association between cortical thickness and YoE among 122 cognitively healthy older human individuals (87 female). We subsequently characterized molecular properties of these regions by…
Proteomic Analysis of Brain Region and Sex-Specific Synaptic Protein Expression in the Adult Mouse Brain
2020
Genetic disruption of synaptic proteins results in a whole variety of human neuropsychiatric disorders including intellectual disability, schizophrenia or autism spectrum disorder (ASD). In a wide range of these so-called synaptopathies a sex bias in prevalence and clinical course has been reported. Using an unbiased proteomic approach, we analyzed the proteome at the interaction site of the pre- and postsynaptic compartment, in the prefrontal cortex, hippocampus, striatum and cerebellum of male and female adult C57BL/6J mice. We were able to reveal a specific repertoire of synaptic proteins in different brain areas as it has been implied before. Additionally, we found a region-specific set…
Detection of Missing Proteins Using the PRIDE Database as a Source of Mass Spectrometry Evidence
2016
The current catalogue of the human proteome is not yet complete, as experimental proteomics evidence is still elusive for a group of proteins known as the missing proteins. The Human Proteome Project (HPP) has been successfully using technology and bioinformatic resources to improve the characterization of such challenging proteins. In this manuscript, we propose a pipeline starting with the mining of the PRIDE database to select a group of data sets potentially enriched in missing proteins that are subsequently analyzed for protein identification with a method based on the statistical analysis of proteotypic peptides. Spermatozoa and the HEK293 cell line were found to be a promising source…