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Symposium 8: Electrophysiological correlates of cognitive processes related to sustained mental effort Symposium Chair: Márk Molnár (Hungary)
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Abstracts / International Journal of Psychophysiology 77 (2010) 206–238
subjects, compared to LH ones, for both hyperalgesia and hypoalgesia conditions, had significantly lower brain electrical activity in the ventral and dorsal posterior cingulate gyrus. HH subjects, as compared to LH ones, during hypnosis, disclosed a lower activation in the posterior cingulate gyrus for the N140 component, and a lower activation in the left middle frontal gyrus for the P200 component. These results support the view that hypoalgesia suggestion in hypnosis reduces frontal brain functions and indicate that hypnotic suggestions can affect attention/ preconscious brain processes involved in pain perception.
doi:10.1016/j.ijpsycho.2010.06.301
Hypnotic analgesia as a consequence of abandoned cortical communication Wolfgang H.R. Miltner*, Ralf Trippe, Holger Hecht, Thomas Weiss Department of Biological and Clinical Psychology, Friedrich Schiller University, Jena, Germany Although hypnosis is well established as an effective method of pain control, little is known on how the human brain constitutes this faculty. Testing the hypothesis that hypnotic analgesia might be due to a breakdown of communication between different brain structures critically involved in the constitution of pain, we here report results of a study that investigated the oscillations of electrical activities recorded by multi array-EEG at different brain sites in 20 subjects, while they were processing noxious stimuli during induced hypnotic analgesia or distracting their attention from stimulation. When subjects were exposed to hypnotic analgesia, data revealed significantly less painful sensations and smaller magnitudes of topographically more-focused brain oscillations within the gamma band above the primary sensory representation areas of the stimulated hand/finger in response to the noxious stimuli, than during distraction. Also, during hypnotic analgesia, slower oscillations were significantly reduced at more extended brain areas spanning the primary and secondary sensory and more frontal executive brain areas. However, more importantly, coherence of fast and slow oscillations within focused and extended brain areas broke down completely during hypnotic oscillations, as compared to the distraction condition. Thus, data confirm the hypothesis that hypnotic analgesia is associated with the breakdown of neural communication within circumscribed brain areas engaged in the constitution of pain.
doi:10.1016/j.ijpsycho.2010.06.302
Symposium 8: Electrophysiological correlates of cognitive processes related to sustained mental effort Symposium Chair: Márk Molnár (Hungary)
doi:10.1016/j.ijpsycho.2010.06.303
On the relationship of frequency and amplitude EEG characteristics of functional states of mental activity Vladimir V. Lazarev Laboratory of Neurobiology and Clinical Neurophysiology, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, 22250-020, Brazil
In EEG studies of the complex forms of mental activity, which cannot be subdivided into time-locked elementary acts, the task-related EEG changes averaged over prolonged epochs can reflect the multidimensional structure of the brain functional state due to different functional significance of different frequency components. The functional integrity of EEG spectral power within the four standard frequency bands was tested in 140 normal subjects by applying factor analysis to the more detailed parameters from period analysis. The frequency and amplitude characteristics of the bands proved to have different functional significance. During arithmetic multiplication, matching rhymes, discriminating tones and clenching fists, the amplitude decrease was intercorrelated in all the bands in proportion to task difficulty and novelty (except for the frontal areas). Two other generalized factors were amplitude-independent. One of them represented EEG acceleration with increase in the frequency and temporal percentage index of beta waves present. It was more evident during successively organized associative verbal operations involving memory scanning. The third factor of alpha frequency deceleration in association with an increase in the theta index probably reflected some active inhibitory processes of mental selectivity, such as voluntary attention, simultaneous organization, and automation of mental operations. The extreme scores of these two factors – the abundance of the first and the deficit of the second one – proved to be characteristic for 67 psychiatric patients suffering from schizotypal disorders with abnormal mental selectivity in cognitive processes. In 19 normal subjects, these factors were indirectly observed in spectral power ratios between the upper and lower subbands of alpha and beta bands evaluated during the same tests. In the anterior areas, an additional regional factor of the delta and theta amplitude synchronization during mental activity was detected, probably reflecting some special type of active inhibitory selectivity. The structure of the factors, comprising the primary EEG parameters of different nature from different frequency bands, and dynamics of the factor values during different types of mental activity show that in determining the functional states and cognitive styles, normal and pathological, the amplitudes of different rhythms can be functionally closer than the amplitude and frequency or the amplitude and index of the same rhythm. doi:10.1016/j.ijpsycho.2010.06.304
Oscillatory EEG and states of sustained cognitive-specific attention S.G. Danko Institute of the Human Brain, Russian Academy of Sciences, St. Petersburg, Russia Sustained optimization of brain resources for certain kinds of mental activity can form basic levels of attention as a multilevel integrative control function of the brain. QEEG-based studies of certain mental brain states, such as rest with open or closed eyes, internally induced emotions, verbal memorizing and retrieval, verbal task solving, and active perception of narrative texts, have taken place in recent years (Danko and collaborators, 2001–2009). It was revealed that transitions between states led to mass statistically significant differences in the time-averaged absolute power and coherence of EEG in a number of frequency bands. Here, comparisons of EEG parameters are presented for states of rest, verbal memorizing, and retrieval, as an example where ability and restrictions of such an approach are most explicit. Methods: EEGs were recorded in 19 standard derivations in 88 healthy subjects, while they were in the following states: rest with eyes open (state EO); memorization (learning) of verbal Latin– Russian semantic pairs (state M); and retrieval from memory
Abstracts / International Journal of Psychophysiology 77 (2010) 206–238
subjects, compared to LH ones, for both hyperalgesia and hypoalgesia conditions, had significantly lower brain electrical activity in the ventral and dorsal posterior cingulate gyrus. HH subjects, as compared to LH ones, during hypnosis, disclosed a lower activation in the posterior cingulate gyrus for the N140 component, and a lower activation in the left middle frontal gyrus for the P200 component. These results support the view that hypoalgesia suggestion in hypnosis reduces frontal brain functions and indicate that hypnotic suggestions can affect attention/ preconscious brain processes involved in pain perception.
doi:10.1016/j.ijpsycho.2010.06.301
Hypnotic analgesia as a consequence of abandoned cortical communication Wolfgang H.R. Miltner*, Ralf Trippe, Holger Hecht, Thomas Weiss Department of Biological and Clinical Psychology, Friedrich Schiller University, Jena, Germany Although hypnosis is well established as an effective method of pain control, little is known on how the human brain constitutes this faculty. Testing the hypothesis that hypnotic analgesia might be due to a breakdown of communication between different brain structures critically involved in the constitution of pain, we here report results of a study that investigated the oscillations of electrical activities recorded by multi array-EEG at different brain sites in 20 subjects, while they were processing noxious stimuli during induced hypnotic analgesia or distracting their attention from stimulation. When subjects were exposed to hypnotic analgesia, data revealed significantly less painful sensations and smaller magnitudes of topographically more-focused brain oscillations within the gamma band above the primary sensory representation areas of the stimulated hand/finger in response to the noxious stimuli, than during distraction. Also, during hypnotic analgesia, slower oscillations were significantly reduced at more extended brain areas spanning the primary and secondary sensory and more frontal executive brain areas. However, more importantly, coherence of fast and slow oscillations within focused and extended brain areas broke down completely during hypnotic oscillations, as compared to the distraction condition. Thus, data confirm the hypothesis that hypnotic analgesia is associated with the breakdown of neural communication within circumscribed brain areas engaged in the constitution of pain.
doi:10.1016/j.ijpsycho.2010.06.302
Symposium 8: Electrophysiological correlates of cognitive processes related to sustained mental effort Symposium Chair: Márk Molnár (Hungary)
doi:10.1016/j.ijpsycho.2010.06.303
On the relationship of frequency and amplitude EEG characteristics of functional states of mental activity Vladimir V. Lazarev Laboratory of Neurobiology and Clinical Neurophysiology, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, 22250-020, Brazil
In EEG studies of the complex forms of mental activity, which cannot be subdivided into time-locked elementary acts, the task-related EEG changes averaged over prolonged epochs can reflect the multidimensional structure of the brain functional state due to different functional significance of different frequency components. The functional integrity of EEG spectral power within the four standard frequency bands was tested in 140 normal subjects by applying factor analysis to the more detailed parameters from period analysis. The frequency and amplitude characteristics of the bands proved to have different functional significance. During arithmetic multiplication, matching rhymes, discriminating tones and clenching fists, the amplitude decrease was intercorrelated in all the bands in proportion to task difficulty and novelty (except for the frontal areas). Two other generalized factors were amplitude-independent. One of them represented EEG acceleration with increase in the frequency and temporal percentage index of beta waves present. It was more evident during successively organized associative verbal operations involving memory scanning. The third factor of alpha frequency deceleration in association with an increase in the theta index probably reflected some active inhibitory processes of mental selectivity, such as voluntary attention, simultaneous organization, and automation of mental operations. The extreme scores of these two factors – the abundance of the first and the deficit of the second one – proved to be characteristic for 67 psychiatric patients suffering from schizotypal disorders with abnormal mental selectivity in cognitive processes. In 19 normal subjects, these factors were indirectly observed in spectral power ratios between the upper and lower subbands of alpha and beta bands evaluated during the same tests. In the anterior areas, an additional regional factor of the delta and theta amplitude synchronization during mental activity was detected, probably reflecting some special type of active inhibitory selectivity. The structure of the factors, comprising the primary EEG parameters of different nature from different frequency bands, and dynamics of the factor values during different types of mental activity show that in determining the functional states and cognitive styles, normal and pathological, the amplitudes of different rhythms can be functionally closer than the amplitude and frequency or the amplitude and index of the same rhythm. doi:10.1016/j.ijpsycho.2010.06.304
Oscillatory EEG and states of sustained cognitive-specific attention S.G. Danko Institute of the Human Brain, Russian Academy of Sciences, St. Petersburg, Russia Sustained optimization of brain resources for certain kinds of mental activity can form basic levels of attention as a multilevel integrative control function of the brain. QEEG-based studies of certain mental brain states, such as rest with open or closed eyes, internally induced emotions, verbal memorizing and retrieval, verbal task solving, and active perception of narrative texts, have taken place in recent years (Danko and collaborators, 2001–2009). It was revealed that transitions between states led to mass statistically significant differences in the time-averaged absolute power and coherence of EEG in a number of frequency bands. Here, comparisons of EEG parameters are presented for states of rest, verbal memorizing, and retrieval, as an example where ability and restrictions of such an approach are most explicit. Methods: EEGs were recorded in 19 standard derivations in 88 healthy subjects, while they were in the following states: rest with eyes open (state EO); memorization (learning) of verbal Latin– Russian semantic pairs (state M); and retrieval from memory