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Background Flow cytometry allows single-cell analysis of peripheral biological samples and is useful in many fields of research and clinical applications, mainly in hematology, immunology, and oncology. In the neurosciences, the flow cytometry separation method was first applied to stem cell extraction from healthy or cerebral tumour tissue and was more recently tested in order to phenotype brain cells, hippocampal neurogenesis, and to detect prion proteins. However, it remains sparsely applied in quantifying membrane receptors in relation to synaptic plasticity. New method We aimed to optimize a flow cytometric procedure for receptor quantification in neurons and non-neurons. A neural dissociation process, myelin separation, fixation, and membrane permeability procedures were optimized to maximize cell survival and analysis in hippocampal tissue obtained from adult rodents. We then aimed to quantify membrane muscarinic acetylcholine receptors (mAChRs) in rats with and without bilateral vestibular loss (BVL). Results mAChR’s were quantified for neuronal and non-neuronal cells in the hippocampus and striatum following BVL. At day 30 but not at day 7 following BVL, there was a significant increase (P ≤ 0.05) in the percentage of neurons expressing M 2/4 mAChRs in both the hippocampus and the striatum. Conclusion Here, we showed that flow cytometry appears to be a reliable method of membrane receptor quantification in ex-vivo brain tissue. [ABSTRACT FROM AUTHOR]

• 3D immersive technology may outperform paper-pen tests in order to explore higher cognitive functions. • Current software remains homemade, not standardized and not directly customizable by researchers or usable by practitioners. • VRmaze software evaluates cognitive functions in humans combining 2 and 3D virtual environments and neuropsychological tests. • Users build or choose calibrated 3D virtual environments, protocols and trials with automatic tracking and analysis modules. • VRmaze offers a translational approach from animal models to patient neuropsychological evaluations. Compared to previous neuropsychological investigations with standard paper-pen tests limited to test complex spatial learning and memory processes, 3-D virtual immersive technology might offer new tools for research purposes and for diagnosis in patients suffering from mild cognitive impairment or dementia. Current software proposes a customizable VR environment combined with an analyser module based on regions of interest and some parameters of analysis or pre-calibrated VR mazes with raw data. We attempted to create the VRmaze software offering either turnkey mazes with automatic tracking and analysis, or more complex and specific virtual mazes for human brain-behavioural research adaptable to all desired settings and parameters of analysis. The software combines 3D pre-calibrated VR tests or free customizable VR tests with digitized neuropsychological 2D standard and validated tests or tasks. We have tested an ERAM, a MWM and a reverse T-maze on 44 healthy subjects, showing gender differences in terms of navigation strategy. We have observed that the choice of benchmarks, instructions, and experimental parameters influence the performances. VRmaze software offers a translational approach for research units that wish to combine animal models and patient evaluations as well as complex 3D tasks and standardized neuropsychological tests combined with an automatic analysis opening a large perspective in the neurosciences to investigate cognitive functions. A clinical module with preconfigured 2- and 3-D tasks should offer clinicians an easy way to evaluate their patients routinely. [ABSTRACT FROM AUTHOR]