The dynamics of activation processes in persons with different ability to recognize speech emotional expressions

The frequency-amplitude characteristics of the brain electrical activity were studied in two groups of subjects: (1) with high and (2) with low indexes of "emotional ear" (the ability to successfully recognize emotions in speech). Comparison of EEG power characteristics between the two groups of subjects permitted the authors to make a conclusion that the persons with lower indexes of "emotional ear" had a much higher EEG activation level as compared to the persons with higher "emotional ear" indexes. A different dynamics of the cortical activation was also observed in the process of recognition of emotions by alpha-rhythm amplitude. It was shown that the persons with higher indexes of recognition had higher alpha-rhythm amplitude, whereas the persons who were less successful in recognition of speech emotions had a contrary tendency: the amplitude on the alpha band decreased in the process of the experiment.     

Adrenal Responses to Stress

Based on concepts proposed by Langley, Cannon, and Selye, adrenal responses to stress occur in a syndrome that reflects activation of the sympathoadrenal system and hypothalamic–pituitary–adrenocortical (HPA) axis; and a “stress syndrome” maintains homeostasis in emergencies such as “fight or flight” situations, but if the stress response is excessive or prolonged then any of a variety of clinical disorders can arise. The idea of a unitary sympathoadrenal system does not account for evidence that different stressors elicit different patterns of autonomic responses, with exposure to some stressors differentially affecting sympathetic noradrenergic and adrenomedullary hormonal activities. Instead, adrenomedullary responses to stressors are more closely tied to adrenocortical than to sympathetic noradrenergic responses. Distress involves concurrent activation of the HPA and adrenomedullary neuroendocrine systems.     

Induction of emotional states by reading aloud texts with various emotional valences and changes in the EEG power in the β and γ frequency bands

The EEG power in the β₁, β₂, and γ frequency bands during reading according to the method of “self-regulatory utterance” was compared in subjects reading aloud emotionally neutral business texts related to an unknown field of activity, fiction texts with clear positive or negative valences or personally important autobiographic texts with similar emotional valences. Two groups of subjects participated in the study: students training to be actors (N = 22) and students with other specializations (N = 23). We observed higher values of the EEG power in the γ (30–40 Hz) and β₂ (18.5–29.5 Hz) frequency bands when comparing the states during reading of emotionally positive and emotionally negative fiction texts and personally important texts. These data are similar to our previous studies with the use of techniques that apply internal induction of positive or negative emotions without speech, in different groups of subjects. Internal induction of positive emotions was associated with an increase in the EEG power in these bands compared to the performance of an emotionally neutral task, whereas induction of negative emotions resulted in a decrease in the EEG power.     

Glucocorticoid-Induced Prenatal Modification of GABA-ergic Regulation of the Responsiveness of the Hypothalamo-Hypophyseal-Adrenocortical System to Stress in Rats

We studied the effects of introduction of exogenous glucocorticoids within the prenatal period (seven subcutaneous injections of hydrocortisone acetate, 50 mg/kg, daily, on the 15th–21st pregnancy days, or two injections on the 16th and 18th days) on the state of the hippocampal GABA-ergic system and the hypothalamo-hypophyseal-adrenocortical system (HHAS) of adult rats under conditions of acute stress (1-h-long immobilization): effects of pre-stress injection of an agonist of GABA_B receptors, baclofen (10 mg/kg, 30 min before immobilization), were also examined. The activity of glutamate decarboxylase and binding of ³H-GABA were the indices characterizing the state of the former regulatory system, while the content of catecholamines in the hypothalamus and the level of hormones of the adrenal cortex characterized the state of the latter system. Prenatal introduction of hydrocortisone acetate resulted in weakening of the adrenocortical reaction to acute stress in adult offspring males; post-stress changes in the noradrenaline level in the hypothalamus and the activity of glutamate decarboxylase in the hippocampus, as well as stress-related activation of GABA_B receptors, were absent in these animals. Adult females subjected to the prenatal influence of hydrocortisone acetate, vice versa, demonstrated a greater reaction of the adrenal cortex to stress; this occurred against the background of suppression of the activity of glutamate decarboxylase in the hippocampus and preserved activity of GABA_B receptors. Our study shows that modifying influences, which exogenous glucocorticoids applied within the prenatal period exert on the GABA-ergic regulation of the responsiveness of the HHAS to stress, are characterized in adult offspring of rats by a significant sex-related dependence. Neirofiziologiya/Neurophysiology, Vol. 37, No. 3, pp. 244–249, May–June, 2005.     

Electroencephalographic (EEG) Measurements of Mindfulness-based Triarchic Body-pathway Relaxation Technique: A Pilot Study

Objective The “Triarchic body-pathway relaxation technique” (TBRT) is a form of ancient Chinese mindfulness-based meditation professed to give rise to positive emotions and a specific state of consciousness in which deep relaxation and internalized attention coexist. The purpose of this study was to examine the EEG pattern generated during the practice of this mindfulness exercise, and compare it to music listening which has been shown to induce positive emotions. Methods Nineteen college students (aged 19–22 years) participated in the study. Each participant listened to both the TBRT and music audiotapes while EEG was recorded. The order of presentation was counterbalanced to avoid order effect. Two EEG indicators were used: (1) alpha asymmetry index, an indicator for left-sided anterior activation, as measure of positive emotions, and (2) frontal midline theta activity, as a measure for internalized attention. Results Increased left-sided activation, a pattern associated with positive emotions, was found during both TBRT exercise and music conditions. However, only TBRT exercise was shown to exhibit greater frontal midline theta power, a pattern associated with internalized attention. Conclusions These results provided evidence to support that the TBRT gives rise to positive emotional experience, accompanied by focused internalized attention.     

Alexithymia impact on EEG activity of anterior and posterior regions of the right hemisphere while experiencing positive and negative emotions

The present study was aimed to assess the influence of alexithymia (an emotional disorder associated with difficulties in identification and describing personal feelings) on regional activity while experiencing positive or negative emotional activation. The 62-channels EEG was recorded in non-alexithymic (n = 27) and alexithymic (n = 17) subjects viewing emotional film clips. Effects of alexithymia were found in the upper theta, low and upper alpha frequency bands; for all the bands the alexithymics exhibited greater reactivity of the right hemisphere, suggesting enhanced avoidance motivational tendencies, negative effect and autonomic arousal. The present phenomenon suggests engagement of additional cognitive resources in identification of emotional feelings. Such a 'cognitive effort' can be a result of impaired referential links and deficit of symbolic processing of emotions.     

Psychophysiological indexes of recognition of emotions in speech

A review of experimental and theoretical works upon perception of emotions in speech is introduced. The main approaches to experimental study and different types of stimulation are considered. Clinical research and experiments upon healthy subjects investigate the brain organization of emotional speech recognition. In the works by Rusalova, Kislova integral psychophysiological preconditions for the successfulness of the recognition of speech emotional expression were studied. As a result of the investigation, extreme groups of persons were identified: with high indices of "emotional hearing" and with low level of recognition of emotions. Analysis of EEG included comparison of different EEG parameters between two groups: values of EEG power, the dominating frequencies, percentage of different EEG-bands in the summary EEG power, coherence, values of EEG inter- and intra-hemispheric asymmetry, etc. The subjects with low identification rates showed a higher brain activation and reactivity both during the emotion identification task and at rest as compared to the subjects with high identification rates. The data obtained reveal specific activation within the left frontal regions, as well as the right posterior temporal cortex during nonverbal recognition of emotions.     

Analysis of evoked potentials from the limbic cortex

In acute experiments on cats we investigated evoked potentials from the cingulate gyrus developed in response to stimulation of somatic and visceral nerves; also potentials from various parts of the hypothalamus, and midbrain reticular formation. We showed that the nonspecific afferent system influences electrical activity in the limbic cortex through hypothalamic pathways. We consider the limbic cortex to be part of the association area of the neocortex and that the associative responses of the cortex are more complex in nature than is usually thought to be the case, and that they are formed under the influence of impulses arriving at the cortex along many specific and nonspecific pathways. The hypothalamo—cingulate system is one of the main systems of cortico—subcortical integration. It plays an important part in regulation of autonomic, somatic, and emotional responses.L. A. Orbeli Institute of Physiology, Academy of Sciences of the Armenian SSR, Erevan. Translated from Neirofiziologiya, Vol. 2, No. 5, pp. 451–459, September–October, 1970.     

Marriage structure of Yakut populations: Migrations

Rural and urban settlements of the Republic of Sakha (Yakutia) are characterized by intense marriage migrations: both indigenous residents of different uluses (districts) of the republic (7–30%) and migrants from outside Yakutia (7–29%) contract marriages in five administrative centers analyzed in this respect. All the populations studied are characterized by a wide geographic range of the birthplaces of persons contracted marriages there (from 14 to 24 uluses of Yakutia), without any predominant migration flow from one district to another. The proportion of homolocal marriages among indigenous ethnic groups (Evenks, Evens, and Yukagirs) is as high as 75–100%; this proportion among Yakuts varies from 26 to 68%; heterolocal marriages are more characteristic of Russian immigrants (41–95%). Positive assortative marriages among persons with the same birthplaces have been found in all populations except for Momsky ulus.     

Psychophysiological mechanisms of stress in subjects with different representation of activation

The EEG spectral power was calculated in 102 students aged 18-25 years in three experimental conditions (during the common educational process, immediately before and after an examination). Before the examination (stress situation), predominant activation of the right anterior cortical quadrant (the area related with negative emotions, according to R. Davidson, 1993) was revealed by the asymmetry coefficient of the beta rhythm. Subjects with low amplitude of the alpha rhythm (more activated) manifested not only emotional but also autonomic disturbances, while only emotional signs were pronounced in students with high alpha (less activated). Increase in the theta rhythm spectral power during stress and its decrease in the poststress period were observed in the less activated persons, which is considered to be a normal reaction to emotionally negative stimuli. On the contrary, in students with low alpha the theta rhythm power in the stress situation was decreased pointing to their emotional instability. In this group, as distinct from the first one, the beta 2 rhythm recorded in the right anterior cortical quadrant did not decrease in the poststress situation. Together with the observed theta rhythm, decrease in the left-hemisphere and bilateral prefrontal areas in the stress situation, this deviation testifies to a predisposition to the reactive depression of these subjects.     

Modulation of High-Frequency EEG Rhythms under Conditions of the Activation Reaction: Dependence on Psychological Characteristics of Personality

In a group of 118 adults of both sexes, we studied modulation of high-frequency EEG rhythms (β and γ components) under conditions of EEG activation related to opening of the eyes. Typical changes in the α rhythm (significant depression in the overwhelming majority of the tested subjects) was accompanied by different (in direction and intensity) shifts of the spectral powers (SPs) of the β and γ components in different subjects. The power of the β1 subcomponent under conditions of the activation reaction increased in 6 persons and dropped in 109 persons; changes in this index in two hemispheres were opposite in their directions in 3 subjects. Thus, changes in the β1 SP upon opening of the eyes were nearly parallel to those of the α rhythm but less intense. The subgroups differentiated according to the pattern of reactivity of the β2 subcomponent included 23, 85, and 10 subjects; for the γ rhythm, the corresponding numbers were 31, 72, and 8. In other words, the patterns of reactivity of β2 and γ oscillations were rather similar to each other but differed significantly from the pattern for the β1 rhythm. Values of the differential coefficients of reactivity (DCRs) of the β1, β2, and γ rhythms demonstrated significant correlations that were especially close for the β2 and γ activity. Within the entire examined group, we found significant negative correlations of the DCR values for β and γ activities with the estimates of some psychological characteristics of the subjects (levels of neuroticism, psychoticism, plasticity, self-control of behavior, and some others) measured using the RTS (Strelau), EPQ (Eysenck), OST (Rusalov), and 16PF (Kettel) questionnaires. The dispersion analysis demonstrated that the above-mentioned subgroups of the subjects (with increase and decrease in the SPs of the β and γ rhythms in both hemispheres and opposite changes of these indices in the right and left hemisphere) showed significant or close to significant specific intergroup differences of a few mean values of the psychological characteristics estimated according to the above questionnaires. Possible mechanisms of modulation of high-frequency EEG components under conditions of the reaction of EEG activation and relations of such changes to the psychological characteristics of the personality are discussed.     

EEG Correlates of Anxiety and Emotional Stability in Adult Healthy Subjects

We studied peculiarities of the spectral characteristics of EEG in 111 healthy adult subjects of both sexes. The levels of situative anxiety (anxiety state) and personal anxiety were estimated using the Spielberger–Khanin test system. To estimate anxiety-related properties of the personality, Cattel’s technique 16 PF (form А) was used. Estimates of situative anxiety demonstrated only two cases of positive correlation with the spectral power density (SPD) of EEG rhythms (SPDs of the beta2 rhythm in the right-hemisphere temporal and occipital regions; recording with the eyes open). Estimates of personal anxiety positively correlated with the SPDs of the beta1 and (especially) beta2 EEG rhythms. Under conditions with the eyes open, the number of significant correlations was greater, and correlations themselves were tighter than with the eyes closed. The closest correlations of the estimates of personal anxiety with the SPDs of the beta rhythm were found in frontal and central leads of both hemispheres and in parietal and occipital loci of the right hemisphere. Only a single case of correlation of the alpha rhythm SPD with personal anxiety (negative correlation, a parietal lead in the left hemisphere) was found. At the same time, rather numerous correlations of the alpha rhythm expression with an index congeneric to anxiety, the C factor by the Cattel’s questionnaire (emotional stability/instability), were found. Thus, the intense beta EEG rhythm can be considered an electrographic correlate of high situative and personal anxieties. At the same time, the alpha rhythm power correlates with the emotional stability of the individual. We suppose that persons with a well-developed alpha rhythm are characterized by active and stable functioning of the cerebral dopaminergic system; this simultaneously serves as a pre-requisite of high emotional stability and social adaptability.     

Correlations of the Characteristics of Evoked EEG Potentials with the Neuroticism Level in Healthy Adults

We studied correlations between the estimates of the neuroticism level (one of the most significant factors of the emotional sphere of a personality) and the amplitude/time characteristics of evoked EEG potentials (EPs). Passive and negative emotiogenic, as well as neutral (from the emotional aspect) visual images (stimuli from the set of the International Affective Picture System, IAPS), were presented to 102 tested persons. The neuroticism level was estimated based on Eysenck’s personality questionnaire. We found that subjects with high estimates of the neuroticism level are characterized, in general, by somewhat higher rates and intensities of processing of emotionally negative information, a higher level of activation of the processes of automatic attention, and readiness to react to both significant and insignificant visual signals (with the aim of probably fighting of a threat). These peculiarities were manifested as relatively shorter latencies of the Р1, N1, Р2, N2, and Р3 components and as higher amplitudes of the Р2 component in the EPs induced by emotionally negative stimuli, as compared with the corresponding indices in subjects with a low neuroticism level. The amplitudes of the N2 component in the case of presentation of negative and neutral stimuli showed a trend toward a decrease. The approach used can be applied for obtaining objective indices interpreted as correlates of peculiarities of the emotional responsiveness typical of a personality.     

Basic emotions evoked by eugenol odor differ according to the dental experience. A neurovegetative analysis.

Subjective individual experiences seem to indicate that odors may form strong connections with memories, especially those charged with emotional significance. In the dental field, this could be the case with the odorant eugenol, responsible for the typical clinging odor impregnating the dental office. The odor of eugenol could evoke memories of unpleasant dental experiences and, therefore, negative feelings such as anxiety and fear, since eugenates (cements containing eugenol) are used in potentially painful restorative dentistry. This hypothesis was tested by evaluating the emotional impact of the odor of eugenol through autonomic nervous system (ANS) analysis. The simultaneous variations of six ANS parameters (two electrodermal, two thermovascular and two cardiorespiratory), induced by the inhalation of this odorant, were recorded on volunteer subjects. Vanillin (a pleasant odorant) and propionic acid (an unpleasant one) served as controls. After the experiment, subjects were asked to rate the pleasantness versus unpleasantness of each odorant on an 11-point hedonic scale. The patterns of autonomic responses, obtained for each odorant and each subject, were transcribed into one of the six basic emotions defined by Ekman et al. (happiness, surprise, sadness, fear, anger and disgust). Results were compared between two groups of subjects divided according to their dental experience (fearful and non-fearful dental care subjects) and showed significant differences only for eugenol. This odorant was rated as pleasant by non-fearful dental subjects but unpleasant by fearful dental subjects. The evoked autonomic responses were mainly associated with positive basic emotions (happiness and surprise) in non-fearful dental subjects and with negative basic emotions (fear, anger, disgust) in fearful dental subjects. These results suggest that eugenol can be responsible for different emotional states depending on the subjects' dental experience, which seems to confirm the potential role of odors as elicitors of emotional memories. This study also supports the possible influence of the ambient odor impregnating the dental office, strengthening a negative conditioning toward dental care in some anxious patients.     

Effects of spatial-imagery task performance on the heart rate variability

Effects of the efficiency of spatial task performance on the autonomic heart control were studied. Dynamic changes in autonomic balance diagnosed on the heart rate variability during maze-model task performance (the type of spatial-imagery activity) showed that the type of heart rate regulation depended on the performance efficiency. The results suggest that in subjects with low performance efficiency, problems in performance are associated with negative emotions that produce the emotional psychogenic stress. In subjects with high efficiency, the autonomic contour of the heart rate regulation prevailed. This was presumable associated with the adequacy of the maze-model task.     

Enhancement of the resistance of the escape reaction to ethanol after substance P]

An ability of substance P (30 micrograms/kg intravenously) to prevent deleterious effects of ethanol (E) (0.5 g/kg intravenously) on central mechanisms of escape reaction elicited by threshold electrical stimulation of the ventromedial hypothalamus was investigated in chronic experiments upon rabbits. Substance P was found to prevent E effects on excitability of the ventromedial hypothalamus (VMH) and on facilitatory influences of the midbrain reticular formation on this emotional centre which were observed in intact animals. Inhibitory effects of the dorsal hippocampus on the VMH could not be evaluated due to its alterations in response to previous substance P administration. The authors suggest that substance P can be considered to be a possible endogenous factor to increase a tolerance of emotional behavioural reactions of an organism to alcohol.     

Convergence of visceral afferent impulses on hypothalamic neurons during vagal and splanchnic nerve stimulation

Responses of posterior and anterior hypothalamic neurons to stimulation of the vagus, splanchnic, and sciatic nerves, and also to photic stimulation were studied by extracellular recording of spike activity in cats anesthetized with chloralose and immobilized with succinylcholine. Most responding neurons of the posterior and anterior hypothalamus did so to stimulation of both vagus and splanchnic nerves. The responses of these polysensory neurons to stimulation of visceral afferents of parasympathetic nerves were identical in sign and mainly excitatory in type. The absence of a reciprocal character of the response to stimulation of "antagonistic" autonomic nerves and the marked polysensory convergence are evidence of the nonspecific "reticular" character of activation of most of the neurons in the posterior and anterior hypothalamus.L. A. Orbeli Institute of Physiology, Academy of Sciences of the Armenian SSR, Erevan. Translated from Neirofiziologiya, Vol. 9, No. 2, pp. 165–170, March–April, 1977.     

The Mere Co-Presence: Synchronization of Autonomic Signals and Emotional Responses across Co-Present Individuals Not Engaged in Direct Interaction

Existing evidence suggests that in social contexts individuals become coupled in their emotions and behaviors. Furthermore, recent biological studies demonstrate that the physiological signals of interacting individuals become coupled as well, exhibiting temporally synchronized response patterns. However, it is yet unknown whether people can shape each other''s responses without the direct, face-to-face interaction. Here we investigated whether the convergence of physiological and emotional states can occur among “merely co-present” individuals, without direct interactional exchanges. To this end, we measured continuous autonomic signals and collected emotional responses of participants who watched emotional movies together, seated side-by-side. We found that the autonomic signals of co-present participants were idiosyncratically synchronized and that the degree of this synchronization was correlated with the convergence of their emotional responses. These findings suggest that moment-to-moment emotional transmissions, resulting in shared emotional experiences, can occur in the absence of direct communication and are mediated by autonomic synchronization.     

The Human Factor: Behavioral and Neural Correlates of Humanized Perception in Moral Decision Making

The extent to which people regard others as full-blown individuals with mental states (“humanization”) seems crucial for their prosocial motivation towards them. Previous research has shown that decisions about moral dilemmas in which one person can be sacrificed to save multiple others do not consistently follow utilitarian principles. We hypothesized that this behavior can be explained by the potential victim’s perceived humanness and an ensuing increase in vicarious emotions and emotional conflict during decision making. Using fMRI, we assessed neural activity underlying moral decisions that affected fictitious persons that had or had not been experimentally humanized. In implicit priming trials, participants either engaged in mentalizing about these persons (Humanized condition) or not (Neutral condition). In subsequent moral dilemmas, participants had to decide about sacrificing these persons’ lives in order to save the lives of numerous others. Humanized persons were sacrificed less often, and the activation pattern during decisions about them indicated increased negative affect, emotional conflict, vicarious emotions, and behavioral control (pgACC/mOFC, anterior insula/IFG, aMCC and precuneus/PCC). Besides, we found enhanced effective connectivity between aMCC and anterior insula, which suggests increased emotion regulation during decisions affecting humanized victims. These findings highlight the importance of others’ perceived humanness for prosocial behavior - with aversive affect and other-related concern when imagining harming more “human-like” persons acting against purely utilitarian decisions.     

Electroencephalograms of patients with initial signs of depression: Independent component analysis

Independent component analysis (ICA) of 19-channel background EEG was performed in 111 patients with the early signs of depressive disorders and in 526 healthy subjects. The power spectra of the independent components were compared in the depressive patients and in healthy subjects at the eyes closed and eyes opened states. Statistically significant differences between the groups were detected in three frequency bands: θ (4–7.5 Hz), α (7.5–14 Hz), and β (14–20 Hz). Increased θ and α activities in parietal and occipital derivations of depressive patients may have been caused by a reduced cortical activity in the projection of these derivation. Diffuse enhancement of the β activity may be correlated with anxiety symptoms that are pronounced in the clinical picture of depressive disorders at early stages of the disease. ICA used to compare quantitative EEG parameters in different groups of patients and in healthy persons makes it possible to localize the differences more accurately than the traditional analysis of EEG spectra.