Grzegorz Marcin Wójcik

Maria Curie-Skłodowska University · Institute of Computer Science

The Guided Imagery technique is reported to be used by therapists all over the world in order to increase the comfort of patients suffering from a variety of disorders from mental to oncology ones and proved to be successful in numerous of ways. Possible support for the therapists can be estimation of the time at which subject goes into deep relaxa...

High-density electroencephalographic (EEG) systems are utilized in the study of the human brain and its underlying behaviors. However, working with EEG data requires a well-cleaned signal, which is often achieved through the use of independent component analysis (ICA) methods. The calculation time for these types of algorithms is the longer the mor...

The aim of this study was to investigate the potential impact of guided imagery (GI) on attentional control and cognitive performance and to explore the relationship between guided imagery, stress reduction, alpha brainwave activity, and attentional control using common cognitive performance tests. Executive function was assessed through the use of...

Trust is the foundation of every area of life. Without it, it is difficult to build lasting relationships. Unfortunately, in recent years, trust has been severely damaged by the spread of fake news and disinformation, which has become a serious social problem. In addition to trust, the factor influencing interpersonal relationships is perceived att...

Brain fog is a kind of mental problem, similar to chronic fatigue syndrome, and appears about 3 months after the infection with COVID-19 and lasts up to 9 months. The maximum magnitude of the third wave of COVID-19 in Poland was in April 2021. The research referred here aimed at carrying out the investigation comprising the electrophysiological ana...

Coronavirus disease 2019 (COVID-19) has caused everything from daily hassles, relationship issues, and work pressures to health concerns and debilitating phobias. Relaxation techniques are one example of the many methods used to address stress, and they have been investigated for decades. In this study, we aimed to check whether there are differenc...

In this study, we explore the simulation setup in computational neuroscience. We use GENESIS, a general purpose simulation engine for sub-cellular components and biochemical reactions, realistic neuron models, large neural networks, and system-level models. GENESIS supports developing and running computer simulations but leaves a gap for setting up...

Brain fog is a kind of mental problem, similar to chronic fatigue syndrome, and appears about 3 months after the infection with COVID-19 and lasts up to 9 months. The maximum magnitude of the third wave of COVID-19 in Poland was in April 2021. The research referred here aimed at carrying out the investigation comprising the electrophysiological ana...

Streszczenie: Medycyna pracy coraz częściej korzysta z nowoczesnych technologii i staje się coraz bardziej interdyscyplinarna. Może to być reakcją zarówno na rozwój nauk medycznych i innych nauk wspierających współczesną praktykę kliniczną, jak również nowe sposoby terapii ukierunkowane na współpracę w ramach zespołu interdyscyplinarnego, zorientow...

Streszczenie: Wypalenie zawodowe (ang. burnout) powstaje w wyniku długotrwałego narażenia na stres związany z pracą. Przejawia się ono w emocjonalnym wyczerpaniu, depersonalizacji i spadku osiągnięć osobistych. W literaturze jest wiele doniesień na temat wypalenia zawodowego wśród pracowników systemu opieki zdrowotnej, ale niewiele jest badań wśród...

Streszczenie: Obecnym wyzwaniem jest zbadanie i optymalizacja obliczeniowych miar wypalenia zawodowego w celu obiektywnego określenia najlepszego sposobu obliczania satysfakcji z pracy, wypalenia zawodowego i predyktorów zamiaru odejścia z pracy w różnych grupach zawodowych.Celem badań prezentowanych w artykule był przegląd badań w zakresie oblicze...

Occupational burnout, manifested by emotional exhaustion, lack of a sense of personal achievement, and depersonalization, is not a new phenomenon, but thusfar, there is no clear definition or diagnostic guidelines. The aim of this article wasto summarize all empirical studies to date that have used medical neuroimaging techniques to provide evidenc...

Understanding how humans evaluate credibility is an important scientific question in the era of fake news. Source credibility is among the most important aspects of credibility evaluations. One of the most direct ways to understand source credibility is to use measurements of brain activity of humans who make credibility evaluations. This article r...

Understanding how humans evaluate credibility is an important scientific question in the era of fake news. Message credibility is among crucial aspects of credibility evaluations. One of the most direct ways to understand message credibility is to use measurements of brain activity of humans performing credibility evaluations. Nevertheless, message...

Behavioral and neuroimaging studies show that people trust and collaborate with others based on a quick assessment of the facial appearance. Based on the morphological characteristics of the face, i.e., features, shape, or color, it is possible to determine health, attractiveness, trust, and some personality traits. The study attempts to indicate t...

In the Internet era, proliferation of fake news can cause serious social and individual consequences. Little is known about why Web users believe or disbelieve fake news. This article aims to make progress in this area by studying brain activity during credibility evaluation. We conducted an experiment that mimics a condition when fake news are eva...

Using the large database of STR (Short Tandem Repeat) DNA results of southeastern Polish population were validated with regard to the correctness of data by testing the interdependence of loci and the Hardy-Weinberg hypothesis. It turned that the data was correct so that this topic was given up. Furthermore, dividing this population according to th...

Objectives The most common technique of determining biological paternity or another relationship among people are the investigations of DNA polymorphism called Fingerprinting DNA. The key concept of these investigations is the statistical analysis, which leads to obtain the likelihood ratio (LR), sometimes called the paternity index. Methods Among...

Objectives The electroencephalographic signal is largely exposed to external disturbances. Therefore, an important element of its processing is its thorough cleaning. Methods One of the common methods of signal improvement is the independent component analysis (ICA). However, it is a computationally expensive algorithm, hence methods are needed to...

Understanding how humans evaluate credibility is an important scientific question in the era of fake news. Source credibility is among the most important aspects of credibility evaluations. One of the most direct ways to understand source credibility is to use measurements of brain activity of humans performing credibility evaluations. Nevertheless...

Understanding how humans evaluate credibility is an important scientific question in the era of fake news. Source credibility is among the most important aspects of credibility evaluations. One of the most direct ways to understand source credibility is to use measurements of brain activity of humans who make credibility evaluations. Nevertheless,...

In the Internet era, understanding why humans find messages from unknown receivers credible (such as fake news) is an important research topic. Message credibility is an important theoretical aspect of credibility evaluation that relies only on message contents and design. For the first time in the field, we study message credibility by directly me...

The electroencephalographic activity of particular brain areas during the decision making process is still little known. This paper presents results of experiments on the group of 30 patients with a wide range of psychiatric disorders and 41 members of the control group. All subjects were performing the Iowa Gambling Task that is often used for dec...

The Event-Related Potentials were investigated on a group of 70 participants using the dense array electroencephalographic amplifier with photogrammetry geodesic station. The source localisation was computed for each participant. The activity of brodmann areas (BAs) involved in the brain cortical activity of each participant was measured. Then the...

The purpose of the present study was to identify the effect of acoustic neurofeedback on brain activity during consecutive stages of mental rotation of 3D objects. Given the fact that the process of mental rotation of objects is associated with desynchronisation of beta rhythm (beta ERD), it was expected that suppression in this band would be great...

Brain-Computer Interfaces (BCI) constitute an alternative channel of communication between humans and environment. There are a number of different technologies which enable the recording of brain activity. One of these is electroencephalography (EEG). The most common EEG methods include interfaces whose operation is based on changes in the activity...

There are still no good quantitative methods to be applied in psychiatric diagnosis. The interview is still the main and most important tool in the psychiatrist work. This paper presents the results of electroencephalographic research with the subjects of a group of 30 patients with psychiatric disorders compared to the control group of healthy vol...

This paper presents the basic research station for the testing of neurofeedback phenomena. The most important part of the system is a hardware module driving a pair of tricolor goggles. This part of the system covers the full 24-bit (RGB) color palette. The goggles used by us eliminate external stimuli and significantly distinguish our station from...

In this paper we present the experimental set-up that was constructed to study Steady State Visually Evoked Potentials (SSVEP). It is based on the DSM-51 unit that works as a hard real-time controller, connected with goggles containing blinking tricolor (RGB) LED diodes. The EEG system used in our experiments was Mindset-1000 with 16 channels, 16 b...

It was previously reported, that temperature may significantly influence neural dynamics on different levels of brain modelling. Due to this fact, while creating the model in computational neuroscience we would like to make it scalable for wide-range of various brain temperatures. However currently, because of a lack of experimental data and an abs...

The interview is still the main and most important tool in psychiatrist's work. The neuroimaging methods such as CT or MRI are widely used in other fields of medicine, for instance neurology. However, psychiatry lacks effective quantitative methods to support of diagnosis. A novel neuroinformatic approach to help clinical patients by means of elect...

Independent Component Analysis (ICA) is known as a signal cleaning method that allows the artifacts to be extracted and subsequently eliminated. It is especially essential while processing the EEG data. However, this is a time-consuming algorithm especially if we deal with a high-dimensional data and take care about the calculation accuracy. One of...

More profound understanding of the relationship between the burnout and the limbic system function can provide better insight into brain structures associated with the burnout syndrome. The objective of this review is to explore all evidence of limbic brain structures associated with the burnout syndrome. In total, 13 studies were selected. Four of...

During processing the EEG signal, the methods of cleaning it from artifacts play an important role. One of the most commonly used methods is ICA (independent component analysis) [1-3]. However, algorithms of this type are computationally expensive. Known implementations of ICA type algorithms rarely include the possibility of parallel computing and...

Component analysis is one of the most important methods used for electroencephalographic (EEG) signal decomposition, and the so-called independent component analysis (ICA) is commonly used. The main function of the ICA algorithm is to find a linear representation of non-Gaussian data whose elements are statistically independent or at least as indep...

The paper describes an application that allows to use a humanoid robot as a stutterer’s assistant and therapist. Auditory and visual feedback has been used in the therapy with a humanoid robot. For this purpose, the common method of “echo” was modified. The modification is that the speaker hears delayed speech sounds uttered by the robot. The sound...

Separation ability is one of two most important properties of Liquid State Machines used in the Liquid Computing theory. To measure the so-called distance of states that Liquid State Machine can exist in - different norms and metrics can be applied. Till now we have used the Euclidean distance to tell the distance of states representing different s...

Electroencephalography (EEG) has become more popular, and as a result, the market grows with new EEG products. The new EEG solutions offer higher mobility, easier application, and lower price. One of such devices that recently became popular is Emotiv EEG. It has been already tested in various applications concerning brain-computer interfaces, neur...

Steady State Visually Evoked Potentials have been known for several decades and they appear in the primary visual cortex of brain as a result of light stimulation of the sense of sight. In this article a simple method for electroencephalographic data acquisition is presented. The system is based on the DSM-51 unit connected to goggles with blinking...

Liquid Computing Theory is a proposal of modelling the behaviour of neural microcircuits. It focuses on creating a group of neurons, known as a liquid layer, responsible for preprocessing of the signal that is being analysed. Specific information is achieved by the readout layers, task oriented groups of neurons, taught to extract particular inform...

In this paper the research on a person declaring synesthetic abilities will be presented. According to the current state of knowledge synesthesia activates additional cortical fields in the brain which can be found in the EEG. The research was conducted using an EGI-EEG system (Electrical Geodesic Inc., Eugene, Oregon, USA) with the GeoSource softw...

Despite the quick development of medicine and associated medical technology, there are still many patients with very severe neurological deficits who need far more sophisticated solutions, such as brain computer interfaces (BCIs). Our research aims at becoming familiar with BCI technology and the assessment of the possibilities of selected subjects...

A diversity of symptoms in autism dictates a broad definition of Autism Spectrum of Disorders (ASD). Each year, the percentage of children diagnosed with ASD is growing. One common diagnostic feature in individuals with ASD is the tendency to exhibit atypical simple cyclic movements. The motor brain activity seems to generate a periodic attractor s...

This paper focuses on finding the most efficinet way of performing local and remote computations with web application based on ActionScript language. Tests involve comparsion of several scenarions which uses pure ActionScript, ActionScript with Alchemy project and ActionScript connecting with C application over AMF protocol and with FileReference c...

Every year the prevalence of Autism Spectrum of Disorders (ASD) is rising. Is there a unifying mechanism of various ASD cases at the genetic, molecular, cellular or systems level? The hypothesis advanced in this paper is focused on neural dysfunctions that lead to problems with attention in autistic people. Simulations of attractor neural networks...

Two and three dimensional models of rat barrel and somatosensory cortex were simulated. Hoddgkin–Huxley and Leaky-Integrate-and-Fire neurons were used to the construction of the networks in GENESIS and PCSIM environments. The dynamics of both models was analysed. Self-organising criticality phenomena were found. Profound investigations of this beha...

The model of mammalian cortical hypercolumn was simulated using liquid state machines built of simple Hodgkin–Huxley neurons. The influence of cell electrical parameters on the system dynamics was investigated. The systematic analysis of the hypercolumn separation ability in the function of time constants, cell membrane capacitance, resistance, Hod...

Frequency of diagnoses of diseases, which belong to Autism Spectrum of Disorders (ASD) increases with each year. The question is: is there a unifying mechanism at molecular, cellular or systems level? In the paper we present our point of view to problem of attention in autistic people. Simulations using neural network model with attractor analysis...

Large and sudden changes in pitch or loudness occur statistically less frequently than gradual fluctuations, which means that natural sounds typically exhibit 1/f spectra. Experiments conducted on human subjects showed that listeners indeed prefer 1/f distributed melodies to melodies with faster or slower dynamics. It was recently demonstrated by u...

This article discusses the first successful phase of our work on the construction of a complete modular research station for EEG signal acquisition and analysis performed in real-time mode and in a way that meets our needs. Our intentions were presented in [1].

Mixed reality techniques are presented. Implementation and application of CAMSHIFT algorithm is discussed to some extent. In the initial stage of the research the technology of real object's edge detection and geometrical figures' representation in the virtual scene has been worked out.

The properties of separation ability and computational efficiency of liquid state machines depend on the neural model employed and on the connection density in the liquid column. A simple model of part of mammalians visual system consisting of one hypercolumn was examined. Such a system was stimulated by two different input patterns, and the Euclid...

This paper presents an approach to facial expression recognition based on the theory of liquid computing. Up to date, no emotion recognition systems based on spiking neural networks exist, and our work is the first attempt in this direction. We investigated the pattern recognition ability of Liquid State Machines based on various neural models, suc...

The model of the part of the rat somatosensory cortex was examined. Large network of Hodgkin-Huxley neurons was simulated and the modular architecture of this structure divided into layers and sub-regions was implemented. High degree of complexity required effective parallelisation of the simulation. In this article the results of the parallel neur...

For this study systems of Hodgkin Huxley neural networks consisting of about 16 thousands of cells are examined. We base on Liquid Computing theory. The separation ability of the system of Liquid State Machines depends on the choice of time constants characterising particular neurons. The main objective of research presented in this article is to i...

Mammalian brains consisting of up to 10 11 neurons belong to group of the most complex systems in the Universe. For years they have been one of the hardest objects of simulation. There are many different approaches to modelling of neurons, but one of the most biologically correct is Hodgkin-Huxley (HH) model. Simulations that require solving a larg...

The idea of electric brain activity acquisition for LINUX OS is presented. So far the only available software has been that for MS-Windows. The general concept of the modular data acquisition system as independent of its particular parts as possible and based on the LINUX pipe system will be discussed to some extent. Adapting the hardware to open s...

Large Hodgkin-Huxley (HH) neural networks were examined and the structures discussed in this article simulated a part of the rat somatosensory cortex. We used a modular architecture of the network divided into layers and sub-regions. Because of a high degree of complexity effective parallelisation of algorithms was required. The results of parallel...