Vyacheslav Orlov

“Cognovisor” for the Human Brain: Towards Mapping of Thought Processes by a Combination of fMRI and Eye-Tracking

The aim of this work was to describe localization of active brain of different types of thinking—spatial and verbal. The method of functional magnetic resonance imaging (fMRI) was used. Seven right-handed healthy volunteers aged from 19 to 30 participated in the experiment. In the experiment, the subject was brought against 6 types of tasks (about 30 of each type) distributed from the figurative to the semantic thought. The results obtained in the statistical parametric and covariance analysis is that interactions of neural networks that are activated to perform the categorization of mental tasks are different. This makes it possible to use this approach to develop a model of “Cognovisor”.

Consciousness in a multilevel architecture: Evidence from the right side of the brain

By taking into account Bruce Bridgemans interest in an evolutionary framing of human cognition, we examine effective (cause-and-effect) connectivity among cortical structures related to different parts of the triune phylogenetic stratification: archicortex, paleocortex and neocortex. Using resting-state functional magnetic resonance imaging data from 25 healthy subjects and spectral Dynamic Causal Modeling, we report interactions among 10 symmetrical left and right brain areas. Our results testify to general rightward and top-down biases in excitatory interactions of these structures during resting state, when self-related contemplation prevails over more objectified conceptual thinking. The right hippocampus is the only structure that shows bottom-up excitatory influences extending to the frontopolar cortex. The right ventrolateral cortex also plays a prominent role as it interacts with the majority of nodes within and between evolutionary distinct brain subdivisions. These results suggest the existence of several levels of cognitive-affective organization in the human brain and their profound lateralization.

Research of Neurocognitive Mechanisms of Revealing of the Information Concealing by the Person

This work is related to the creation of an MR-compatible polygraph and the development of methods for detecting the hierarchy of neural networks of the cognitive organization of hidden memory markers. At the moment, there is practically no scientific work on lie detection, in which both the classical polygraph and the MRI scanner were simultaneously used. Combining these methods will help increase the probability of recognizing the facts of hiding important information and carry out an objective assessment of the truthfulness of the reported information. This method can also be used to detect the level of resistance of operators for emotional stress, assess the perception of emotional stimuli by subjects in neurocognitive tasks.

fMRI and Tractographic Studies of Cognitive Systems in the Human Brain at the Norm and the Paranoid Schizophrenia

This study is aimed at a systematic study of the work of neural networks of the human brain and their architecture in norm and in schizophrenia. To obtain the neurophysiological data, a unique complex of experimental equipment for world-class neurocognitive studies was used. The data obtained showed a significant decrease in the structural connectivity relationships for the rich club coefficient for a group of schizophrenic patients compared with the norm. Perception of emotionally negative visual and audio stimuli related to delusions in patients with schizophrenia does not lead to a significant decrease in BOLD signal as compared with the norm in Calcarine_L, Cerebelum_4_5_R, ParaHippocampal_LR, Precuneus_L, Temporal_Sup_R areas. The differences found in the structural and functional patterns of cognitive-affective disorders can serve as prognostic biomarkers in patients with schizophrenia and will make a significant contribution to the development of high-tech diagnostics in the early stages of mental illness.

Contrasting Human Brain Responses to Literature Descriptions of Nature and to Technical Instructions

The problem of semantic mapping of the brain is one of the urgent problems in human neurocognitive studies. At the present time there are only few studies reported in the world literature, all of which are made on the material and with the participation of English language native speakers. Russian language can thus become the second language for which this kind of research will be carried out, namely, finding out a correspondence between the semantic classes of the Russian vocabulary and the cortical areas responsible for processing these semantic classes when the text is orally presented. To solve this problem, it is necessary to develop techniques that allow us to investigate cognitive and neurolinguistic mechanisms of perception and understanding of the continuous text segments in natural language. In this paper, we present data on the comparative mapping of the human brain structures involved in the perception of meaningful texts containing technical instructions and literature descriptions of nature.

Functional Neural Networks in Behavioral Motivations

Functional magnetic resonance imaging (fMRI) is an effective non-invasive tool for exploration and analysis of brain functions. Here functional neural networks involved in behavioral motivations are studied using fMRI. It was found that behavioral conditions producing different motivations for action can be associated with different patterns of functional network activity. At the same time, connection can be made to dynamics of socio-emotional cognition, decision making and action control, described by the Virtual Actor model based on the eBICA cognitive architecture. These preliminary observations encourage further fMRI-based study of human social-emotional cognition. The impact is expected on the emergent technology of humanlike collaborative robots (cobots) and creative cognitive assistants.

Experimental Model of Study of Consciousness at the Awakening: FMRI, EEG and Behavioral Methods

For the study of neuronal correlates of consciousness, a simple and effective model is the comparison of sleeping and waking states. Consciousness turns off during sleep and turns on at waking. The moment of awakening from sleep is a promising model for the study of neurophysiological correlates of consciousness. We developed a psychomotor test, the monotonous performance of which, causes within 60 min alternating episodes with the disappearance of consciousness when falling asleep (the “microsleep”) and its restoration upon awakening (wakefulness). When performing this test, the subject with closed eyes counts from 1 to 10 and simultaneously presses sensitive buttons, alternately with the right and left hands. Spontaneous restoration of the test after the episode of “microsleep” requires the activation of consciousness, which is accompanied by consciously performing the test with counting and simultaneously pressing the buttons. EEG methods allow you to accurately assess the moments of the transition of sleep/wakefulness, the levels of wakefulness and the depth of sleep, and behavioral methods, by indicators of the correctness of the performance of the psychomotor test - to determine the levels of consciousness. We showed reproducibility of this test obtained both under normal conditions and in conditions of functional magnetic resonance imaging (fMRI) procedure. In 10 out of 14 subjects during a 60-min experiment performed in the MRI scanner, 3–48 episodes of “microsleep” were recorded with subsequent awakening. Preliminary results showed an increase in the activity of the visual regions (the region of the calcarine sulcus) of the cerebral cortex, left pre-cuneus/cuneus, etc. during sleep and regions of the right thalamus, left cuneus, cerebellar zones, stem structures, etc. at the moment of awakening and resumption of conscious activity.

On Alternative Instruments for the fMRI Data Analysis: General Linear Model Versus Algebraic Topology Approach

This work aimed at comparing two different approaches (classical general linear model based on the Bayesian approach and the method of algebraic topology) for fMRI data processing in a simple motor task. Subjects imposes block paradigm, consisting of three identical blocks. The duration of each block was 40 s (20 s of rest and 20 s of right hand fingers busting). To obtain statistically significant results were carried out 20 sessions of experiment. The results obtained by both methods were very close to each other, but correspondence between statistically significant changes in BOLD-signal was not quite complete. TDA (topologic data analyses) allocated additional voxels in Post central gyrus right. This region could be revealed with the changing in the level of confidence in the GLM model, but with this lower level of confidence too much additional voxels appeared. Combination of two approaches could be used for verification of results.