Pain fingerprinting using multimodal sensing: pilot study

Pain is a complex phenomenon, the experience of which varies widely across individuals. At worst, chronic pain can lead to anxiety and depression. Cost-effective strategies are urgently needed to improve the treatment of pain, and thus we propose a novel home-based pain measurement system for the longitudinal monitoring of pain experience and variation in different patients with chronic low back pain. The autonomous nervous system and audio-visual features are analyzed from heart rate signals, voice characteristics and facial expressions using a unique measurement protocol. Self-reporting is utilized for the follow-up of changes in pain intensity, induced by well-designed physical maneuvers, and for studying the consecutive trends in pain. We describe the study protocol, including hospital measurements and questionnaires and the implementation of the home measurement devices. We also present different methods for analyzing the multimodal data: electroencephalography, audio, video and heart rate. Our intention is to provide new insights using technical methodologies that will be beneficial in the future not only for patients with low back pain but also patients suffering from any chronic pain.

Computational simulations and Ca2+ imaging reveal that slow synaptic depolarizations (slow EPSPs) inhibit fast EPSP evoked action potentials for most of their time course in enteric neurons

Transmission between neurons in the extensive enteric neural networks of the gut involves synaptic potentials with vastly different time courses and underlying conductances. Most enteric neurons exhibit fast excitatory post-synaptic potentials (EPSPs) lasting 20-50 ms, but many also exhibit slow EPSPs that last up to 100 s. When large enough, slow EPSPs excite action potentials at the start of the slow depolarization, but how they affect action potentials evoked by fast EPSPs is unknown. Furthermore, two other sources of synaptic depolarization probably occur in enteric circuits, activated via GABAA or GABAC receptors; how these interact with other synaptic depolarizations is also unclear. We built a compartmental model of enteric neurons incorporating realistic voltage-dependent ion channels, then simulated fast EPSPs, slow EPSPs and GABAA or GABAC ligand-gated Cl- channels to explore these interactions. Model predictions were tested by imaging Ca2+ transients in myenteric neurons ex vivo as an indicator of their activity during synaptic interactions. The model could mimic firing of myenteric neurons in mouse colon evoked by depolarizing current during intracellular recording and the fast and slow EPSPs in these neurons. Subthreshold fast EPSPs evoked spikes during the rising phase of a slow EPSP, but suprathreshold fast EPSPs could not evoke spikes later in a slow EPSP. This predicted inhibition was confirmed by Ca2+ imaging in which stimuli that evoke slow EPSPs suppressed activity evoked by fast EPSPs in many myenteric neurons. The model also predicted that synchronous activation of GABAA receptors and fast EPSPs potentiated firing evoked by the latter, while synchronous activation of GABAC receptors with fast EPSPs, potentiated firing and then suppressed it. The results reveal that so-called slow EPSPs have a biphasic effect being likely to suppress fast EPSP evoked firing over very long periods, perhaps accounting for prolonged quiescent periods seen in enteric motor patterns.Author SummaryThe gastrointestinal tract is the only organ with an extensive semi-autonomous nervous system that generates complex contraction patterns independently. Communication between neurons in this “enteric” nervous system is via depolarizing synaptic events with dramatically different time courses including fast synaptic potentials lasting around 20-50 ms and slow depolarizing synaptic potentials lasting for 10 – 120 s. Most neurons have both. We explored how slow synaptic depolarizations affect generation of action potentials by fast synaptic potentials using computational simulation of small networks of neurons implemented as compartmental models with realistic membrane ion channels. We found that slow synaptic depolarizations have biphasic effects; they initially make fast synaptic potentials more likely to trigger action potentials, but then actually prevent action potential generation by fast synaptic potentials with the inhibition lasting several 10s of seconds. We confirmed the inhibitory effects of the slow synaptic depolarizations using live Ca imaging of enteric neurons from mouse colon in isolated tissue. Our results identify a novel form of synaptic inhibition in the enteric nervous system of the gut, which may account for the vastly differing time courses between signalling in individual gut neurons and rhythmic contractile patterns that often repeat at more than 60 s intervals.

Perceived facial happiness during conversation correlates with insular and hypothalamus activity for humans, not robots. An investigation of the somatic marker hypothesis applied to social interactions.

The somatic marker hypothesis posits that perceiving emotions entails reenacting markers of self emotions, in particular in the autonomous nervous system. Well studied in decision-making tasks, it has not been tested in a social cognitive neuroscience framework, and in particular for the automatic processing of positive emotions during natural interactions. Here, we address this question using a unique corpus of brain activity recorded during unconstrained conversations between participants and a human or a humanoid robot. fMRI recordings are used to test whether activity in the most important brain regions in relation to the autonomic system, the amygdala, hypothalamus and insula, is affected by the level of happiness expressed by the human and robot agents. Results indicate that for the hypothalamus and the insula, in particular the anterior agranular region strongly involved in processing social emotions, activity in the right hemisphere increases with the level of happiness expressed by the human, but not the robot. Results indicate that perceiving positive emotions in social interactions induces the local brain responses predicted by the somatic marker hypothesis, but only when the interacting agent is a real human.

Neurophysiological features in patients with migraine at risk for epilepsy

Objective: to study the electrophysiological parameters of brain bioelectric activity and features of the autonomous nervous system assessing heart rate variability, sympathetic skin response, clinical and physiological tests depending on the lateralization of migraine pain syndrome in the right or left brain hemisphere in patients with epileptic electroencephalogram (EEG) signs and migraine.Material and methods. Thirty six patients with aura-free episodic migraine at risk of developing epilepsy and 9 age-matched healthy subjects were examined. All participants underwent EEG, clinical and physiological tests, assessment of heart rate variability and sympathetic skin response.Results. Patients with right-hemisphere migraine headache had signs of activated sympathetic nervous system at baseline level and during exercise, lower baseline EEG epileptiform activity and in provocative tests. In contrast to the subjects of this group, patients of other group featured with a more stable migraine pain syndrome in the left hemisphere tended to dominate with functional activity of the parasympathetic system such as increased trophotropic support during exercise, as well as greater magnitude of baseline epileptiform bioelectric activity and during load tests.Conclusion. Values of heart rate variability in combination with objective results of clinical and physiological assessment of the autonomous nervous system and electrophysiological parameters of brain bioelectric activity are reliable prognostic indicators for varying functional conditions in patients with episodic migraine.

Comparison of the Scorpionism Caused by Centruroides margaritatus, Tityus pachyurus and Tityus n. sp. aff. metuendus Scorpion Venoms in Colombia

Among other scorpion species, Colombia has two genera of the Buthidae family Centruroides and Tityus, considered to be dangerous to humans. This research shares scientific knowledge aiming to a better understanding about the pathophysiological effects of such venoms. The venom of the three species: Centruroides margaritarus, Tityus pachyurus, and T. n. sp. aff. metuendus with biomedical interest were studied. An initial pre-glycemic sample was taken from ICR mice. They were later intraperitoneally inoculated with doses of 35% and 70% of LD50 of total venom. Poisoning signs were observed during a 6-h period to determine the level of scorpionism. After observation, a second glycemic sample was taken, and a histopathological evaluation of different organs was performed. This work revealed that all three venoms showed considerably notorious histopathological alterations in main organs such as heart and lungs; and inducing multiple organ failure, in relation to the glycemia values, only C. margaritatus and T. n. sp. aff. metuendus showed significant changes through manifestation of hyperglycemia. According to the Colombian scorpionism level; signs were mild to severe affecting the autonomous nervous system.

A Comprehensive Review of Techniques for Processing and Analyzing Fetal Heart Rate Signals

The availability of standardized guidelines regarding the use of electronic fetal monitoring (EFM) in clinical practice has not effectively helped to solve the main drawbacks of fetal heart rate (FHR) surveillance methodology, which still presents inter- and intra-observer variability as well as uncertainty in the classification of unreassuring or risky FHR recordings. Given the clinical relevance of the interpretation of FHR traces as well as the role of FHR as a marker of fetal wellbeing autonomous nervous system development, many different approaches for computerized processing and analysis of FHR patterns have been proposed in the literature. The objective of this review is to describe the techniques, methodologies, and algorithms proposed in this field so far, reporting their main achievements and discussing the value they brought to the scientific and clinical community. The review explores the following two main approaches to the processing and analysis of FHR signals: traditional (or linear) methodologies, namely, time and frequency domain analysis, and less conventional (or nonlinear) techniques. In this scenario, the emerging role and the opportunities offered by Artificial Intelligence tools, representing the future direction of EFM, are also discussed with a specific focus on the use of Artificial Neural Networks, whose application to the analysis of accelerations in FHR signals is also examined in a case study conducted by the authors.

A Wave Theory of the Mind: A Coherent Mind Creates a Strong Mind and Healthy Body

Brain waves have been detected and measured. These waves are electro-magnetic waves that flow through the membranes of cells and nerve fibers. Amplitude and frequency modulation (AM and FM) carries the information from cell to cell while the myelin coating prevents the information from being distorted. The Nodes of Ranvier are the regeneration stations so the information wave doesn’t die out. Interference of the waves creates holographic memories, coherent waves creating much stronger holograms than incoherent waves, which are far weaker than coherent waves. The autonomous nervous system carries health guided information (Placebo effect) the more coherent the signal, the stronger the health information is. Methods to create a positive, coherent mind and healthy body are given.