Igor Riecansky
Slovak Academy of Sciences, Centre of Experimental Medicine, Department Member
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Lexical–semantic retrieval emerges through the interactions of distributed prefrontal and perisylvian brain networks. Growing evidence suggests that synchronous theta band neural oscillations might play a role in this process, yet, their... more
Lexical–semantic retrieval emerges through the interactions of distributed prefrontal and perisylvian brain networks. Growing evidence suggests that synchronous theta band neural oscillations might play a role in this process, yet, their functional significance remains elusive. Here, we used transcranial alternating current stimulation to induce exogenous theta oscillations at 6 Hz (θ-tACS) over left prefrontal and posterior perisylvian cortex with a 180° (anti-phase) and 0° (in-phase) relative phase difference while participants performed automatic and controlled retrieval tasks. We demonstrate that θ-tACS significantly modulated the retrieval performance and its effects were both task- and phase-specific: the in-phase tACS impaired controlled retrieval, whereas the anti-phase tACS improved controlled but impaired automatic retrieval. These findings indicate that theta band oscillatory brain activity supports binding of semantically related representations via a phase-dependent mod...
The neural mechanisms underpinning empathy for pain are still a matter of debate. One of the major questions is whether empathy-related pain responses indicate domain-general vs. pain-specific affective responses. Using fMRI and... more
The neural mechanisms underpinning empathy for pain are still a matter of debate. One of the major questions is whether empathy-related pain responses indicate domain-general vs. pain-specific affective responses. Using fMRI and psychopharmacological experiments, we investigated if placebo analgesia reduces first-hand and empathic experiences of affective touch, and compared them to the effects on pain. Placebo analgesia also affected the first-hand and empathic experience of unpleasant touch, implicating domain-general effects. However, and in contrast to pain and pain empathy, administering an opioid antagonist did not block these effects. Moreover, placebo analgesia reduced neural activity related to both modalities in the bilateral insular cortex, while it specifically modulated activity in the anterior midcingulate cortex for pain and pain empathy. These findings provide causal evidence that one of the major neurochemical systems for pain regulation is involved in pain empathy,...
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Pain is a salient, aversive sensation which motivates avoidance, but also has a strong social signaling function. Numerous studies have shown that regions of the nervous system active in association with first-hand pain are also active in... more
Pain is a salient, aversive sensation which motivates avoidance, but also has a strong social signaling function. Numerous studies have shown that regions of the nervous system active in association with first-hand pain are also active in response to the pain of others. When witnessing somatic pain, such as seeing bodies in painful situations, significant activations occur not only in areas related to the processing of negative emotions, but also in neuronal structures engaged in somatosensation and the control of skeletal muscles. These empathy-related sensorimotor activations are selectively reviewed in this article, with a focus on studies using electrophysiological methods and paradigms investigating responses to somatic pain. Convergent evidence from these studies shows that these activations (1) occur at multiple levels of the nervous system, from the spinal cord up to the cerebral cortex, (2) are best conceptualized as activations of a defensive system, in line with the role ...
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Research increasingly suggests that nitric oxide (NO) plays a role in the pathogenesis of schizophrenia. One important line of evidence comes from genetic studies, which have repeatedly detected an association between the neuronal isoform... more
Research increasingly suggests that nitric oxide (NO) plays a role in the pathogenesis of schizophrenia. One important line of evidence comes from genetic studies, which have repeatedly detected an association between the neuronal isoform of nitric oxide synthase (nNOS or NOS1) and schizophrenia. However, the pathogenetic pathways linking nNOS, NO, and the disorder remain poorly understood. A deficit in sensorimotor gating is considered to importantly contribute to core schizophrenia symptoms such as psychotic disorganization and thought disturbance. We selected three candidate nNOS polymorphisms (Ex1f-VNTR, rs6490121 and rs41279104), associated with schizophrenia and cognition in previous studies, and tested their association with the efficiency of sensorimotor gating in healthy human adults. We found that risk variants of Ex1f-VNTR and rs6490121 (but not rs41279104) were associated with a weaker prepulse inhibition (PPI) of the acoustic startle reflex, a standard measure of sensor...
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Cognitive flexibility emerges from an interplay of multiple cognitive systems, of which lexical-semantic and executive are thought to be the most important. Yet this has not been addressed by previous studies demonstrating that such forms... more
Cognitive flexibility emerges from an interplay of multiple cognitive systems, of which lexical-semantic and executive are thought to be the most important. Yet this has not been addressed by previous studies demonstrating that such forms of flexible thought deteriorate under stress. Motivated by these shortcomings, the present study evaluated several candidate mechanisms implied to mediate the impairing effects of stress on flexible thinking. Fifty-seven healthy adults were randomly assigned to psychosocial stress or control condition while assessed for performance on cognitive flexibility, working memory capacity, semantic fluency, and self-reported cognitive interference. Stress response was indicated by changes in skin conductance, hearth rate, and state anxiety. Our analyses showed that acute stress impaired cognitive flexibility via a concomitant increase in sympathetic arousal, while this mediator was positively associated with semantic fluency. Stress also decreased working ...
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Chylová M., Marko M., Dragašek J., Virčík M., Rovný R., Roháriková V., Murínová J., Cimrová B., Katina S., Riečanský I. Slovak adaptation of the Schizotypal Personality Questionnaire. Ceskoslovenska Psychologie, 2017, 61(3), 267-280.... more
Chylová M., Marko M., Dragašek J., Virčík M., Rovný R., Roháriková V., Murínová J., Cimrová B., Katina S., Riečanský I. Slovak adaptation of the Schizotypal Personality Questionnaire. Ceskoslovenska Psychologie, 2017, 61(3), 267-280.
Objectives. The aim of the present study was to adapt the Schizotypal Personality Questionnaire (SPQ), one of the most widely used methods for the assessment of schizotypy, into the Slovak language and investigate its basic psychometric properties (reliability, latent structure, gender differences, and measurement invariance) in healthy volunteers.
Sample and setting. The Slovak version of the questionnaire (SPQ-SK) was completed by 267 responders (120 men and 147 women) with a
mean age of 25.3 years (SD = 5.5). SPQ includes 74 binary items arranged into 9 subscales.
Hypotheses. Latent structure of two concurrent models, a three-factor and a four-factor model were tested.
Statistical analysis. Gender differences were assessed by Welch t-test. Internal consistency was assessed using Cronbach’s alpha and ordinal alpha. Confrmatory factor analysis (CFA) was calculated using the maximum likelihood method. χ2-test, CFI, RMSEA, SRMR, AIC and
BIC were used to evaluate and compare the respective models. Measurement invariance was assessed by χ2 and CFI differences.
Results. SPQ-SK showed an acceptable internal consistency. On average, men scored higher in the dimensions Odd or Eccentric Behavior, No
Close Friends, and Constricted Affect, whereas women scored higher on Excessive Social Anxiety and Magical Thinking. CFA indicated that a modified three-factor structure represented the best model for SPQ-SK. This model also showed configural invariance and weak measurement invariance. However, strong and strict invariance was only partially supported.
Study limitations. The research sample consisted of healthy individuals. Further investigations are needed to determine clinically relevant scores.
Objectives. The aim of the present study was to adapt the Schizotypal Personality Questionnaire (SPQ), one of the most widely used methods for the assessment of schizotypy, into the Slovak language and investigate its basic psychometric properties (reliability, latent structure, gender differences, and measurement invariance) in healthy volunteers.
Sample and setting. The Slovak version of the questionnaire (SPQ-SK) was completed by 267 responders (120 men and 147 women) with a
mean age of 25.3 years (SD = 5.5). SPQ includes 74 binary items arranged into 9 subscales.
Hypotheses. Latent structure of two concurrent models, a three-factor and a four-factor model were tested.
Statistical analysis. Gender differences were assessed by Welch t-test. Internal consistency was assessed using Cronbach’s alpha and ordinal alpha. Confrmatory factor analysis (CFA) was calculated using the maximum likelihood method. χ2-test, CFI, RMSEA, SRMR, AIC and
BIC were used to evaluate and compare the respective models. Measurement invariance was assessed by χ2 and CFI differences.
Results. SPQ-SK showed an acceptable internal consistency. On average, men scored higher in the dimensions Odd or Eccentric Behavior, No
Close Friends, and Constricted Affect, whereas women scored higher on Excessive Social Anxiety and Magical Thinking. CFA indicated that a modified three-factor structure represented the best model for SPQ-SK. This model also showed configural invariance and weak measurement invariance. However, strong and strict invariance was only partially supported.
Study limitations. The research sample consisted of healthy individuals. Further investigations are needed to determine clinically relevant scores.
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Electroencephalography (EEG) provides no direct link between electrode positions and underlying signal generators. Inferences based on spatial proximity between scalp positions and cortical structures are not reliable. More accurate... more
Electroencephalography (EEG) provides no direct link between electrode positions and underlying signal generators. Inferences based on spatial proximity between scalp positions and cortical structures are not reliable. More accurate source localization is obtained by solving both the forward and the inverse problem, but is technically challenging. In this paper, we provide a reference table of correspondence between EEG sensors and cortical anatomical regions based on a realistic head model. We also present a universal algorithm to compute the solution by using a forward model to determine the sensitivity for electrodes of any defined electrode positioning system and cortical anatomical parcellation.
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Empathy for pain activates brain areas partially overlapping with those underpinning the first-hand experience of pain. It remains unclear, however, whether such shared activations imply that pain empathy engages similar neural functions... more
Empathy for pain activates brain areas partially overlapping with those underpinning the first-hand experience of pain. It remains unclear, however, whether such shared activations imply that pain empathy engages similar neural functions as first-hand pain experiences. To overcome the limitations of previous neuroimaging research, we pursued a conceptually novel approach: we used the phenomenon of placebo analgesia to experimentally reduce the first-hand experience of pain, and assessed whether this results in a concomitant reduction of empathy for pain. We first carried out a functional MRI experiment (n = 102) that yielded results in the expected direction: participants experiencing placebo analgesia also reported decreased empathy for pain, and this was associated with reduced engagement of anterior insular and midcingulate cortex: that is, areas previously associated with shared activations in pain and empathy for pain. In a second step, we used a psychopharmacological manipulation (n = 50) to determine whether these effects can be blocked via an opioid antagonist. The administration of the opioid antagonist naltrexone blocked placebo analgesia and also resulted in a corresponding "normalization" of empathy for pain. Taken together, these findings suggest that pain empathy may be associated with neural responses and neurotransmitter activity engaged during first-hand pain, and thus might indeed be grounded in our own pain experiences.
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Previous research in social neuroscience has consistently shown that empathy for pain recruits brain areas that are also activated during the first-hand experience of pain. This has been interpreted as evidence that empathy relies upon... more
Previous research in social neuroscience has consistently shown that empathy for pain recruits brain areas that are also activated during the first-hand experience of pain. This has been interpreted as evidence that empathy relies upon neural processes similar to those underpinning the first-hand experience of emotions. However, whether such overlapping neural activations imply that equivalent neural functions are engaged by empathy and direct emotion experiences remains to be demonstrated. We induced placebo analgesia, a phenomenon specifically modulating the first-hand experience of pain, to test whether this also reduces empathy for pain. Subjective and neural measures of pain and empathy for pain were collected using self-report and event-related potentials (ERPs) while participants underwent painful electrical stimulation or witnessed that another person was undergoing such stimulation. Self-report showed decreased empathy during placebo analgesia, and this was mirrored by redu...
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Isoflavones are a subgroup of phytoestrogens, natural plant substances with structure similar to 17-beta-estradiol and capable of binding to estrogen receptors (ERs). Isoflavones possess higher affinity to ERbeta than to ERalpha and may... more
Isoflavones are a subgroup of phytoestrogens, natural plant substances with structure similar to 17-beta-estradiol and capable of binding to estrogen receptors (ERs). Isoflavones possess higher affinity to ERbeta than to ERalpha and may have a potency to activate both genomic and non-genomic estrogen signaling pathways. In addition, isoflavones interact with the metabolism of steroid hormones. Therefore, the actions of isoflavones are rather complex and may be related to large number of factors, which are not satisfactorily identified yet. Recently, isoflavones have come into focus of interest due to several reports about their positive effect on human health, in particular prevention of hormone-dependent cancers, cardiovascular diseases, osteoporosis, adverse menopausal manifestations and age-related cognitive decline. Isoflavones may bring new insights into the mechanisms of physiological regulations and increase the possibilities of medical interventions.
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The saccadic eye movement related potentials (SEMRPs) enable to study brain mechanisms of the sensorimotor integration. SEMRPs provide insight into various cognitive mechanisms related to planning, programming, generation and execution of... more
The saccadic eye movement related potentials (SEMRPs) enable to study brain mechanisms of the sensorimotor integration. SEMRPs provide insight into various cognitive mechanisms related to planning, programming, generation and execution of the saccadic eye movements. SEMRPs can be used to investigate pathophysiological mechanisms of several disorders of the central nervous system. Here we shortly summarize basic findings concerning the significance of SEMRP components, their relationship to the functional brain asymmetry and visual attention level as well as changes related to certain neuropsychological disorders.
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Chaotic transitions likely emerge in a wide variety of cognitive phenomena and may be linked to specific changes during the development of mental disorders. They represent relatively short periods in the behavior of a system, which are... more
Chaotic transitions likely emerge in a wide variety of cognitive phenomena and may be linked to specific changes during the development of mental disorders. They represent relatively short periods in the behavior of a system, which are extremely sensitive to very small changes. This increased sensitivity has been suggested to occur also during retrieval of stressful emotional experiences because of their fragmentary, temporally and spatially disorganized character. To test this hypothesis we recorded EEG during retrieval of fearful memories related to panic attack in 7 patients and retrieval of anxiety-related memories in 11 healthy controls. Nonlinear data analysis of EEG records showed a statistically significant increase in degree of chaotic dynamics after retrieval of stressful memories in majority of patients as well as in control subjects. This change correlated with subjective intensity of anxiety induced during the memory retrieval. The data suggest a role of nonlinear chang...
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Extrastriate area V5 was identified in many primates including humans. V5 represents an important substrate for visual motion processing. Neurons in this area show a sharp preference for direction and speed of visual stimuli. Neuronal... more
Extrastriate area V5 was identified in many primates including humans. V5 represents an important substrate for visual motion processing. Neurons in this area show a sharp preference for direction and speed of visual stimuli. Neuronal activity correlates with the ability to detect and discriminate motion in several psychophysical paradigms. The nature of neuronal representation of motion in V5 is much debated currently. The following article provides a summary of basic anatomical, neurophysiological, neuropsychological, and behavioural data related to the role of area V5 in the processing of visual motion information.
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Research Interests: Perception, Electrophysiology, Schizophrenia, Cognition, Electroencephalography, and 25 moreSynchronization, Visual Cortex, Brain Mapping, Vision, Humans, Cerebral Cortex, Female, Male, Oscillations, Gamma Band, Flicker, Steady state, Sensorimotor synchronisation, Phase Locking, Perceptual grouping, Adult, Stimulation, Backward Masking, Visual Evoked Potentials, Time Domain, Oscillation, Contour Integration, Case Control Studies, Neuropsychological Tests, and Synchronisation(Synchronization, Visual Cortex, Brain Mapping, Vision, Humans, Cerebral Cortex, Female, Male, Oscillations, Gamma Band, Flicker, Steady state, Sensorimotor synchronisation, Phase Locking, Perceptual grouping, Adult, Stimulation, Backward Masking, Visual Evoked Potentials, Time Domain, Oscillation, Contour Integration, Case Control Studies, Neuropsychological Tests, and Synchronisation)
(Synchronization, Visual Cortex, Brain Mapping, Vision, Humans, Cerebral Cortex, Female, Male, Oscillations, Gamma Band, Flicker, Steady state, Sensorimotor synchronisation, Phase Locking, Perceptual grouping, Adult, Stimulation, Backward Masking, Visual Evoked Potentials, Time Domain, Oscillation, Contour Integration, Case Control Studies, Neuropsychological Tests, and Synchronisation)
The 2nd Schizophrenia International Research Society Conference, was held in Florence, Italy, April 10-15, 2010. Student travel awardees served as rapporteurs of each oral session and focused their summaries on the most significant... more
The 2nd Schizophrenia International Research Society Conference, was held in Florence, Italy, April 10-15, 2010. Student travel awardees served as rapporteurs of each oral session and focused their summaries on the most significant findings that emerged from each session and the discussions that followed. The following report is a composite of these reviews. It is hoped that it will provide an overview for those who were present, but could not participate in all sessions, and those who did not have the opportunity to attend, but who would be interested in an update on current investigations ongoing in the field of schizophrenia research.
Research Interests: Genetics, Brain Imaging, Schizophrenia, Cognition, Scientific Societies, and 3 moreBrain, Humans, and Animals
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Research Interests: Psychology, Cognitive Science, Electrophysiology, Intelligence, Spatial cognition, and 21 moreCognition, Performance, Electroencephalography, Individual Differences, Humans, Female, Male, Mental rotation, Reaction Time, Parietal Cortex, Mental processes, Task Performance, Adult, Parietal Lobe, Analysis of Variance, Neuropsychologia, Indexation, Rotation, Individual Difference, Visual Evoked Potentials, and Neurosciences(Cognition, Performance, Electroencephalography, Individual Differences, Humans, Female, Male, Mental rotation, Reaction Time, Parietal Cortex, Mental processes, Task Performance, Adult, Parietal Lobe, Analysis of Variance, Neuropsychologia, Indexation, Rotation, Individual Difference, Visual Evoked Potentials, and Neurosciences)
(Cognition, Performance, Electroencephalography, Individual Differences, Humans, Female, Male, Mental rotation, Reaction Time, Parietal Cortex, Mental processes, Task Performance, Adult, Parietal Lobe, Analysis of Variance, Neuropsychologia, Indexation, Rotation, Individual Difference, Visual Evoked Potentials, and Neurosciences)
The influence of musical experience on free-recall dichotic listening to environmental sounds, two-tone sequences, and consonant-vowel (CV) syllables was investigated. Sixty healthy right-handed participants were divided into two groups... more
The influence of musical experience on free-recall dichotic listening to environmental sounds, two-tone sequences, and consonant-vowel (CV) syllables was investigated. Sixty healthy right-handed participants were divided into two groups according to their active musical competence ('musicians' and 'non-musicians'). A left ear advantage (LEA) for nonverbal stimuli (environmental sounds and two-tone sequences) whereas a right ear advantage (REA) for CV syllables was found in both groups. Dichotic listening to environmental sounds was uninfluenced by musical experience. The total accuracy of recall for two-tone sequences was higher in musicians than in non-musicians but the lateralization was similar in both groups. For CV syllables a lower REA was found in male but not female musicians in comparison to non-musicians. The results indicate a specific sex-dependent effect of musical experience on lateralization of phonological auditory processing.
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Pripfl J, Tomova L, Riecansky I, Lamm C. Transcranial magnetic stimulation of the left dorsolateral prefrontal cortex decreases cue-induced nicotine craving and EEG delta power. Brain Stimul. 2014 Mar-Apr;7(2):226-33. doi:... more
Pripfl J, Tomova L, Riecansky I, Lamm C. Transcranial magnetic stimulation of
the left dorsolateral prefrontal cortex decreases cue-induced nicotine craving
and EEG delta power. Brain Stimul. 2014 Mar-Apr;7(2):226-33. doi:
10.1016/j.brs.2013.11.003.
TMS has high potential as smoking cessation treatment. However, the neural mechanisms underlying TMS induced reduction of tobacco craving remain unclear. Electroencephalographic (EEG) delta frequency has been associated with the activity of the dopaminergic brain reward system, which is crucial for nicotine induced effects, and decreases after nicotine admission in smokers. The aim of this study was to investigate EEG delta power changes induced by hf rTMS of the left dorsolateral prefrontal cortex (DLPFC) in nicotine deprived smokers and it's relation to cue-induced nicotine craving. Fourteen healthy smokers meeting ICD-10 criteria for tobacco addiction participated in this within-subject sham controlled study. Participants had to abstain from smoking 6 h before the experiment. Effects of high-frequency repetitive TMS (hf rTMS) (10 Hz) for verum (left DLPFC) and sham (vertex) stimulations on cue-induced nicotine craving and resting state EEG delta power were assessed before and three times within 40 min after rTMS. Both craving (P = 0.046) and EEG delta power (P = 0.048) were significantly lower after verum stimulation compared to sham stimulation across the whole post stimulation time period assessed. However, changes of craving ratings and delta power did not correlate. Hf rTMS applied to the left DLPFC reduces nicotine craving in short-term abstinent smokers. Changes in delta activity support the idea that stimulation induced effects are mediated by the dopaminergic brain reward system, which presumably plays a prominent, but probably not exclusive, role in this stimulation induced behavioral modulation, making this method a promising smoking cessation treatment candidate.
the left dorsolateral prefrontal cortex decreases cue-induced nicotine craving
and EEG delta power. Brain Stimul. 2014 Mar-Apr;7(2):226-33. doi:
10.1016/j.brs.2013.11.003.
TMS has high potential as smoking cessation treatment. However, the neural mechanisms underlying TMS induced reduction of tobacco craving remain unclear. Electroencephalographic (EEG) delta frequency has been associated with the activity of the dopaminergic brain reward system, which is crucial for nicotine induced effects, and decreases after nicotine admission in smokers. The aim of this study was to investigate EEG delta power changes induced by hf rTMS of the left dorsolateral prefrontal cortex (DLPFC) in nicotine deprived smokers and it's relation to cue-induced nicotine craving. Fourteen healthy smokers meeting ICD-10 criteria for tobacco addiction participated in this within-subject sham controlled study. Participants had to abstain from smoking 6 h before the experiment. Effects of high-frequency repetitive TMS (hf rTMS) (10 Hz) for verum (left DLPFC) and sham (vertex) stimulations on cue-induced nicotine craving and resting state EEG delta power were assessed before and three times within 40 min after rTMS. Both craving (P = 0.046) and EEG delta power (P = 0.048) were significantly lower after verum stimulation compared to sham stimulation across the whole post stimulation time period assessed. However, changes of craving ratings and delta power did not correlate. Hf rTMS applied to the left DLPFC reduces nicotine craving in short-term abstinent smokers. Changes in delta activity support the idea that stimulation induced effects are mediated by the dopaminergic brain reward system, which presumably plays a prominent, but probably not exclusive, role in this stimulation induced behavioral modulation, making this method a promising smoking cessation treatment candidate.
Research Interests: Transcranial Magnetic Stimulation, Electroencephalography, Prefrontal Cortex, Reward, Humans, and 10 moreSmoking Cessation, Cues, Nicotine, Female, Male, Young Adult, Neuronavigation, Craving, Brain Stimulation, and Adult(Smoking Cessation, Cues, Nicotine, Female, Male, Young Adult, Neuronavigation, Craving, Brain Stimulation, and Adult)
(Smoking Cessation, Cues, Nicotine, Female, Male, Young Adult, Neuronavigation, Craving, Brain Stimulation, and Adult)
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... in men; whereas women outperform men in verbal abili-ties, visual memory and perceptual speed (Maccoby and Jacklin, 1974; Kimura ... that sex differences in mental rotation are more clearly found with difficult paradigms (Collins and... more
... in men; whereas women outperform men in verbal abili-ties, visual memory and perceptual speed (Maccoby and Jacklin, 1974; Kimura ... that sex differences in mental rotation are more clearly found with difficult paradigms (Collins and Kimura, 1997; Jansen-Osman and Heil ...
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There is evidence that development and maintenance of neural connections are disrupted in major mental disorders, which indicates that neurotrophic factors could play a critical role in their pathogenesis. Stress is a well-established... more
There is evidence that development and maintenance of neural connections are disrupted in major mental disorders, which indicates that neurotrophic factors could play a critical role in their pathogenesis. Stress is a well-established risk factor for psychopathology and recent research suggests that disrupted signaling via brain-derived neurotrophic factor (BDNF) may be involved in mediating the negative effects of stress on the brain. Social isolation of rats elicits chronic stress and is widely used as an animal model of mental disorders such as schizophrenia and depression. We carried out a systematic search of published studies to review current evidence for an altered expression of BDNF in the brain of rats reared or housed in social isolation. Across all age groups (post-weaning, adolescent, adult), majority of the identified studies (16/21) reported a decreased expression of BDNF in the hippocampus. There are far less published data on BDNF expression in other brain regions. Data are also scarce to assess the behavioral changes as a function of BDNF expression, but the downregulation of BDNF seems to be associated with increased anxiety-like symptoms. The reviewed data generally support the putative involvement of BDNF in the pathogenesis of stress-related mental illness. However, the mechanisms linking chronic social isolation, BDNF expression and the elicited behavioral alterations are currently unknown.