Anatomical and functional brain approach along short abrupt changes in G-levels

To conduct experiments under abrupt changes in g-levels, a single-engine aerobatic aircraft has been used, providing 6-8 seconds of reduced gravity, preceded and followed by 5-7 seconds of hypergravity periods. Due to the specific conditions of the flight and previous findings [1], the hypothesis of the present work lies on the idea that some sensory inputs could have a notorious effect on brain final responses when gravity is altered. Therefore, this study focuses on the evaluation of such hypothesis, based on the analysis of the evolution in time of intracranial activity of limbic, visual and auditory cortices. Five subjects (N=5, age 41¿14 years) have flown in parabolic flight with their eyes both open and closed. Electroencephalogram signals were recorded with an Emotive Epoc headset, synchronized with a triaxial accelerometer. The intracranial brain bioelectric activity (standardized current density) throughout the parabola, was calculated by applying Standard Low Resolution Brain Electromagnetic Tomography, and it was analyzed for the limbic, visual and auditory cortices. Intracranial activity of the Temporal, Parietal and Occipital lobes were carried out as well in order to compare the different periods/phases of the flight. Results detected a lower brain activity during the hypogravity phase in all lobes and cortices, only in the case of open eyes. The bioelectrical brain activity along the parabola showed similar patterns in all lobes and cortices, when visual inputs are highlighted. Suppressing the sight, two major behaviors were detected in brain activity: one for temporal lobe and auditory cortex, and second one for the rest of the lobes and visual cortex. It Seemed that, flying with closed eyes, other sensory stimuli were enhanced, in this case the auditory cortex. To confirm the validity of the results two-way ANOVA (factors lobe/phases) and Fisher post hoc test have been applied on mean intracranial activity values in all cases. Spectral entropy evolution in time has been considered as a fast indicator of the sudden extracranial brain activity variation during short g-changes. For open eyes, spectral entropy values indicated a slight decrease at the onset of the hypogravity phase, whereas in case of closed eyes, this change was detected in the last seconds of the parabola, even though these fluctuations were statistically non-significant. Results suggest that some of the sensory inputs can indeed have an impact on brain final response, when gravity conditions are altered.Peer ReviewedPostprint (published version

EEG changes and C-Trend parameters in healthy patients during induction of anesthesia

Abstract. EEG has become technically viable tool in intensive care and there are technologies like C-Trend that compress the complex EEG recording into easy-to-interpret parameters. C-Trend Index is especially designed for evaluation of the brain function during sedation in intensive care patients. In this work, the precepts of EEG, EEG usage during anesthesia practice, including the use of EEG parameters in patients’ overall assessment and C-Trend monitoring in identifying brain states under propofol were discussed. The data consisted of segments of 20 EEG recordings collected from healthy subjects who underwent anesthetic infusions while responding to stimuli to directly determine unconsciousness. The purpose of this work was to evaluate how the parameters that C-Trend provides (C-Trend Index, BSR, aEEG and ADR) behave in patients with healthy brain function during anesthesia and how they correlate with changes that we see in raw EEG and clinical signs such as loss of consciousness. It has been demonstrated that some parameters of qEEG, such as the C-Trend Index and BSR, may predict unconsciousness (results from individual t-test for C-Trend before and after loss of consciousness state are 65.70, p-value is < 0.001 for the smoothed C-Trend Index). Hence, these measures can be utilised in future studies to monitor a neurologically healthy patient’s level of anaesthesia

A Feasibility Study of Quantifying Longitudinal Brain Changes in Herpes Simplex Virus (HSV) Encephalitis Using Magnetic Resonance Imaging (MRI) and Stereology.

OBJECTIVES: To assess whether it is feasible to quantify acute change in temporal lobe volume and total oedema volumes in herpes simplex virus (HSV) encephalitis as a preliminary to a trial of corticosteroid therapy. METHODS: The study analysed serially acquired magnetic resonance images (MRI), of patients with acute HSV encephalitis who had neuroimaging repeated within four weeks of the first scan. We performed volumetric measurements of the left and right temporal lobes and of cerebral oedema visible on T2 weighted Fluid Attenuated Inversion Recovery (FLAIR) images using stereology in conjunction with point counting. RESULTS: Temporal lobe volumes increased on average by 1.6% (standard deviation (SD 11%) in five patients who had not received corticosteroid therapy and decreased in two patients who had received corticosteroids by 8.5%. FLAIR hyperintensity volumes increased by 9% in patients not receiving treatment with corticosteroids and decreased by 29% in the two patients that had received corticosteroids. CONCLUSIONS: This study has shown it is feasible to quantify acute change in temporal lobe and total oedema volumes in HSV encephalitis and suggests a potential resolution of swelling in response to corticosteroid therapy. These techniques could be used as part of a randomized control trial to investigate the efficacy of corticosteroids for treating HSV encephalitis in conjunction with assessing clinical outcomes and could be of potential value in helping to predict the clinical outcomes of patients with HSV encephalitis

Application of the Artificial Intelligence Algorithms with a Cognitive Graphic as a Tool for a System Analysis of Electrophysiological Processes

Summarizing the accumulated experience for a long time in the polyparametric cognitive modeling of different physiological processes (electrocardiogram, electroencephalogram, electroreovasogram and others) and the development on this basis some diagnostics methods give ground for formulating a new methodology of the system analysis in biology. The gist of the methodology consists of parametrization of fractals of electrophysiological processes, matrix description of functional state of an object with a unified set of parameters, construction of the polyparametric cognitive geometric model with artificial intelligence algorithms. The geometry model enables to display the parameter relationships are adequate to requirements of the system approach. The objective character of the elements of the models and high degree of formalization which facilitate the use of the mathematical methods are advantages of these models. At the same time the geometric images are easily interpreted in physiological and clinical terms. The polyparametric modeling is an object oriented tool possessed advances functional facilities and some principal features

visualization of mind: visual exploration of brain activity

Since ancient times, philosophical and religious thinkers have made attempts to understand the nature of the mind. Today, new developments in technology enable scientists and researchers to explore the brain’s complex physical activity, revealing a deeper mental reality. Moreover, the emergence of low-cost biometric devices gives nonscientific communities an ability to explore usage of biometric data in variety of ways. This project explores visualization of human brain activity using electroencephalogram neural interface to create a visually engaging and meaningful user experience. The implementation of the project takes a form of an interactive installation. It projects the visual form, whose visual parameters are changed in real-time based on the participant’s brain wave signal values. The brain activity is monitored by the electroencephalogram (EEG) neural interface, which transmits the brain wave signal data of the participant’s brain activity to the computer program. The program analyzes signal values and manipulates the visual form. In order to create a meaningful and useful experiences, the research was conducted in areas of cognitive science, philosophy, symbolism and visual design. The visual form was designed based on the Kalachakra Mandala, a circular diagram used in the Tibetan Buddhist tradition. It was selected as a reference because of its deep philosophical meaning and purpose. The user experience was evaluated based on qualitative methods that consisted of interviews and written questionnaires. It provided insights into the user’s experience and helped to determine potential applications. The method of recording and analyzing mathematical data of the brain activity was used to determine a credible quantitative evaluation method to be used in the future. The evaluation showed the majority of participants who tested the installation had a calming and relaxing experience. Many of them indicated the project has a high potential to be used for meditation and therapy purposes