GABA

Inhibitory neurotransmitter GABA is known to play a critical role in perception, yet has been under-explored in humans. Understanding the mechanisms of visual perception is of particular relevance to conditions such as autism spectrum conditions, where differences in sensory perception are a core feature. Here we exploit the high resolution of 7-Tesla Magnetic Resonance Spectroscopy (MRS) to investigate the links between occipital GABA, autistic traits, and perceptual choice in humans. 45 participants (22 Female: 23 Male), aged 19-39 years, completed the Autism Spectrum Quotient questionnaire

…lead to altered expression of the GABA and dopamine (DA) systems in key re

…by interacting with both glutamate and GABA. Little is known about how nitrergic system works in the autistic brain, although several studies suggest that dysregulations in this system may be involved in the pathogenesis of autism.We

…inhibitory potentials induced by GABA and glycine. Motoneuron axotomy induces KCC2 downregulation, which seems to recover with target reinnervation. Thus, we tested the hypothesis that neurotrophic factors might play an important role in regulating KCC2 levels. In this context, we provided axotomized extraocular motoneurons with VEGF or BDNF to determine whether these factors influence the lesion-induced KCC2 downregulation. Adult rats w

…effect of γ-amino butyric acid (GABA) in PD and the underlying mechanism focusing on WNT/β-catenin signaling mediated by the MAPK pathway. We treated MPTP-induced SH-SY5Y cells with GABA Low and High concentrations, and we also treated PD model mice with GABA. GABA treatment effectively reduced the expression of biomarkers associated with PD, particularly lewy’s bodies and α-synuclein, and increased the number of tyrosine hydroxylase positive cells. G

The iGABASnFR is a genetically encoded optical sensor that can detect the inhibitory neurotransmitter GABA. Its recent improvements have allowed it to reliably monitor GABA release evoked by electric stimulation (Marvin et al., Nature Methods 2019) or epileptiform activity (Magloire et al., Curr Biol. 2023). Here, we employed iGABASnFR2, both neuronal and astrocytic variants, virally expressed in the hippocampus or somatosensory cortical region for ~4 weeks of in vivo transduction for high-resolution multiplexed two-photon excitation imaging in acute hippocampal slices or in the barrel cortex

…expressing both somatostatin and GABA. These cells form synapses with pyramidal neurons and other interneurons, crucial for modulating cortical information processing and maintaining excitation/inhibition balance. Originating from the medial ganglionic eminence, SST+ interneurons follow a tangential pathway to the cortex, making them susceptible to gene mutations affecting neuronal migration. One such gene, Platelet-activating factor

Gamma-aminobutyric acid (GABA) plays a key role in learning and brain plasticity by regulating functional connectivity and oscillatory activity in local circuits and global brain networks. Altered cortical inhibition is associated with perceptual and learning impairments in psychiatric disorders such as schizophrenia. Despite the importance of GABAergic inhibition for brain function, we lack a mechanistic understanding of the inhibitory network dynamics that support adaptive behaviour from training. To unravel these mechanisms, we developed a progressive 3-stimuli touchscreen orientation discr

Information processing and communication in neuronal circuits is enabled by networks of dynamic inter-areal coupling of neuronal oscillations. These networks exhibit frequency-specific spatial and topological patterns and rely on hubs that are crucial for information routing. Oscillations are generated by fast synaptic neurotransmission among pyramidal cells and interneurons, and are subject to neuromodulation on slower timescales in a frequency- and region-specific manner. Efferent connections, receptor densities, and neurotransmitter reuptake regulation of neuromodulatory systems are highly

…levels of gamma-aminobutyric acid (GABA) in the brain. The present study used proton magnetic resonance spectroscopy (1H-MRS) with the Mescher-Garwood point-resolved spectroscopy sequence (MEGA-PRESS) to measure GABA levels in the pregenual anterior cingulate cortex (pgACC)/medial prefrontal cortex (MPFC). We also assessed resting-state functional connectivity using functional magnetic resonance imaging (rs-fMRI). Ana

Social status is key to mental health and well-being. The nucleus accumbens (NAc) regulates motivated behaviors, including the establishment of social hierarchies. Our recent work underscored NAc mitochondrial energy metabolism as critical for social competition among rodents. However, the exact neurochemical and molecular underpinnings of the differences in NAc energy metabolism and the specific contribution of distinct cell types are yet to be determined. Magnetic resonance spectroscopy (MRS) allows the study of metabolites related to energy metabolism, neurotransmission, and cellular integr

The loss of a sensory input leads to reorganization of neuronal networks in remaining sensory cortices, which results in functional improvements. This shows remarkable adaptability of the mammalian brain. It remains elusive whether a traumatic brain injury (TBI) in a sensory cortex results in similar functional reorganization in spared sensory networks. We herein investigated global alterations in neuronal activity maps in the mouse brain subjected to a TBI in the visual cortex and delved into the underlying cellular mechanisms. Our data shows substantial differences in brain activity maps 2-3

…including acetylcholine (ACh), GABA and adenosine, which regulate the amplitude and activity-sensitivity of DA release. Adrenoceptors are expressed throughout the striatum but their role, and that of norepinephrine (NE) as a potential striatal neuromodulator, is poorly understood. Given only a sparse norepinephrinergic input of the striatum but the dense innervation by DA, the endogen

Background: The lateral hypothalamus (LH), known to play roles in modulation of reward, avoidance, and preference, projects to the associated brain regions such as the ventral tegmental area (VTA), lateral habenula (LHb), and rostromedial tegmental nucleus (RMTg). Previous studies have established that LH neurons projecting to LHb influence cocaine-induced behavior and dopamine release. However, the specific neuronal populations and the peptides involved in cocaine-induced behavioral effects have not been elucidated.Purpose: To address this, our study aimed to investigate the roles of LH neuro

Transcranial ultrasound neuromodulation (TUS) is a fast growing non-invasive brain stimulation method allowing reversible and local perturbation of the neuronal activity in superficial but also deep-brain structures. Although TUS efficiency has been shown at the circuit and behavioral levels, its precise impact on the neuronal tissue remains a subject of ongoing investigation. Using resting-state fMRI (rs-fMRI) and MRI spectroscopy (MRS), we characterized both the functional and metabolic effects of TUS on a subcortical structure, the amygdala.In two anaesthetized non-human primates, We select

…intermittent collapse of feed-forward GABAergic inhibition. Inhibition could fail through multiple mechanisms, including (i) an attenuation or even reversal of the driving force for chloride in postsynaptic neurons because of intense activation of GABAA receptors, (ii) an elevation o

…versions for following glutamate, GABA, acetylcholine, serotonin), optogenetic effectors including the new “enhanced Magnets” dimerizers, AAV serotypes for retrograde labeling & altered tropism, probes for correlative light-electron microscopy, chemical gene switches, etc. He will make all his slides freely available - so don’t wo

…our recent studies describing how GABA-mediated Ca2+ activity regulates the production of aberrant adult-

…potential ("voltage"), glutamate, GABA, acetylcholine, serotonin, dopamine, etc. He will also cover optogenetics tools and methods for correlative light/electron microscopy. They make all tools freely available to everyone and work to get them in the hands of people that have limited resources.

…changes we observe in glutamate and GABA during various paradigms, including simple motors tasks and reinforcement learning. In the second part, I’ll present a new approach to MRS that focuses on measuring the relaxation times (T1, T2) of metabolites, which reflect changes to specific cellular microenvironments. I will explain why these can be exciting markers for studying several in-vivo pa

My research uses a range of methods to better understand how the brain’s natural chemicals control complex behaviours, thoughts and perceptions. I also have a particular fascination about the factors that determine the contents of an individual’s conscious experience. In this talk I will present work that sits at the intersection of these two research areas looking at the role of different neurotransmitter systems in driving changes in conscious state. Specifically, I will discuss a series of studies using ambiguous stimuli to explore the neuropharmacological processes that underly alternation

Understanding how neural circuits in the brain compute information not only requires determining how individual inhibitory and excitatory elements of circuits are wired together, but also a detailed knowledge of their functional interactions. Recent advances in optogenetic techniques and mouse genetics now offer ways to specifically probe the functional properties of neural circuits with unprecedented specificity. Perhaps one of the most heavily interrogated circuits in the mouse brain is one in the retina that is involved in coding direction (reviewed by Mauss et al., 2017; Vaney et al., 2012