Functional Brain System during Probabilistic Forecasting

Functional Brain System during Probabilistic Forecasting

162 IOP 2016 affective categories. Main findings show how the characteristic biphasic cardiac response, usually observed with short presentation of t...

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162

IOP 2016

affective categories. Main findings show how the characteristic biphasic cardiac response, usually observed with short presentation of threatening pictures, extends to long lasting stimuli and showed clear differences also within the three aversive categories. Furthermore, results are in agreement with the hypothesis of a parasympathetic recruitment during the experience of a compassionate, focused-on-others, emotional state. Finally, stimuli depicting natural environments, used in past research as neutral condition, revealed to be a clear pleasant condition, eliciting physiological responses differentiated by the real neutral ones (city documentaries). Results point also to a different gender-related sensitivity to emotions, especially to the negative ones, which may explain the observed greater risk of women to develop a mood disorder.

of sympathetic nervous system, crucial to effectively enter and cope with a stressful situation; they may also testify to the chronic character of stress reactions among the EH patients, which is marked by signs of psychophysiological exhaustion. Such an interpretation is verified by data of personality traits of the patients. Conclusion: Results of the present research expand the very notion of etiology and pathogeny of EH.

doi:10.1016/j.ijpsycho.2016.07.465

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doi:10.1016/j.ijpsycho.2016.07.464 Functional Brain System during Probabilistic Forecasting

286 Response of Renin–angiotensin–aldosterone System to Emotional Stress in Patients with Various Forms of Essential Hypertension Elena I. Pervichkoa, Olga D. Ostroumovab, Yury P. Zinchenkoa, Tatiana F. Gusevab a Faculty of Psychology, Lomonosov Moscow State University, Moscow, Russia b Faculty of General Medicine, Moscow State University of Medicine and Dentistry, Moscow, Russia Background: Correlation of sympathetic-adrenal system and renin–angiotensin–aldosterone system (RAAS) indicates one of the central psychophysiological mechanisms, responsible for increase in blood pressure (BP) of patients with essential hypertension (EH). At the same time, there is poorly understanding of the RAAS contribution to the pathogenesis of stress-induced EH. The study was aimed to analyze RAAS reaction within experimental simulation of emotional stress in patients with ‘Hypertension at work’ and patients, whose BP on working days and days off were equal. Methods: Simulation of emotional stress employed the procedure of assessment of the aspiration level. BP values, the level of renin (R) and angiotonin I (A1) in blood plasma were taken before and after the experiment. The 16PF Questionnaire (Cattell, Mead, 2008) was introduced to examine personality traits. There were examined 85 patients with ‘Hypertension at work’ (mean age was 45.9±2.8 years), and 85 patients with the ‘classical’ of EH (mean age was 47.4±4.5 years). Results: Patients with ‘Hypertension at work’, when compared with those of ‘classical’ EH had a significant higher increase of systolic BP (SBP) in response to stress loads (16.1±1.9 mmHg and 4.1±0.7 mmHg; pb0.001). Initial examinations showed significantly lower (pb0.05) values of R (1.04±0.21ngr/ml)/day) and A1 (1.14±0.13 (ngr/ml)/day in the group of ‘Hypertension at work’ patients, when compared with patients of the ‘classical’ EH (R (0.86±0.21 (ngr/ml)/day) и A1 (1.26±0.09 (ngr/ml)/day). After the experiment R and A1 values in the group of patients with ‘Hypertension at work’ showed a considerable decrease (ΔR=(-0.2) (ngr/ml)/day, pb0.05; ΔA1=(-0.18) (ngr/ml)/day, pb0.05), as for the second group, they significantly increased (ΔR=0.4 (ngr/ml)/day, pb0.05; ΔA1=0.09 ngr/ml)/day). The study of personality factors revealed significant (pb0.05) divergence of results for patients with ‘Hypertension at work’ and ‘classical’ EH on A, C, F, O, Q1, and Q4 scales in 16 PF. The trait profile of the former showed personality ambivalence and emotional tension coupled with continence in expression of emotions. Discussion: Obtained results make it clear that most of the patients with ‘Hypertension at work’ demonstrate no ‘pre-run alert’

Stanislav A. Kozlovskiya, Natalia S. Buldakovaa, Alexander Vartanova, Andrey A. Kiselnikova, Julia A. Marakshinaa,b a Lomonosov Moscow State University, Moscow, Russia b Psychological Institute of Russian Academy of Education, Moscow, Russia Functional systems associated with the probabilistic forecasting were researched. Probabilistic forecasting is a process of making a decision when multiple solutions are available. Participants (N=28) were shown with quasirandom sequence of three digits (1, 2, 3). A digit was presented for 700 ms followed by a 1500 ms pause. The participant’s task was guess what the subsequent digit would be and press the corresponding button. Each participant also completed two control tasks: a perception test (which required pressing the button of the presented digit) and a memory test (1-back). After the EEG registration, ERP calculation and filtering the results (MFS algorithm, Vartanov, 2002) dipole sources were localized (two-dipole dynamic model, KD≥0.95, Talairach’s coordinates). The relative frequency of a dipole appearing at a specific brain structure during a 100 ms period was calculated. To do so an ERP was divided into 10 overlapping periods with 50 ms shifts. Using the T-test, the significant dipole spacing differences (p≥0.05) between the three tasks for a group of participants were revealed. The brain structures in which there was a difference for at least one period were selected. Then a factor analysis with Varimax rotation was performed. Three factors were revealed. The factor loading allocation fully corresponded with the experimental assignments thus allowing for the interpretation of these factors as functional systems. Calculating the factor scores allows localizing these functional systems in the brain. The system of probabilistic forecasting (factor 1) includes the following associated structures listed according to their contribution to the system: right midbrain, right inferior frontal gyrus, left superior temporal gyrus, left parahippocampal gyrus, right posterior cingulate, right parahippocampal gyrus, left BA (Brodmann area) 47, left orbital gyrus, right BA 25, right temporal lobe sub-gyral, right BA 30, left putamen, left amygdala, left brainstem, right cingulate gyrus, left cerebellum. The highest activation of this system was observed around 200-300 ms after presentation of a stimulus. We suppose that the system evaluated the efficiency of the last forecast and the improvement of the following assumption. This corresponds with the previously obtained data that basic decision making model consists of two interactive schemes: evaluating each variant and selecting the best possible. During the other two tasks the activation of this system was 4 times lower and was only observed around 50-150 ms after presentation of a stimulus. The research was supported by the Russian Science Foundation (project № 16-18-00066).

doi:10.1016/j.ijpsycho.2016.07.466