촉각자극에 의한 자율신경계 및 뇌파 반응과 감성

( Estate Sokhadze ),이경화 ( Kyung Hwa Lee ),이임갑 ( Im Gap Yi ),박세훈 ( Se Hun Park ),손진훈 ( Jin Hun Sohn ) 한국감성과학회 1998 추계학술대회 Vol.1998 No.-

The purpose of the current study was comparative analysis of autonomic and electrocortical responses to passive and active touch of the tektites with different subjective emotional preference. Perspective goal of the project is development of a template for classification of tactile stimuli according to subjective comfort and associated physiological manifestations. The study was carried out on 36 female college students. Physiological signals were acquired by Grass and B1OPAC 100 systems with AcqKnowledge III software. Frontal, parietal and occipital EEG (relative power spectrum /percents/ of EEG bands - delta, theta, slow and fast alpha, low and fast beta), and autonomic variables, namely heart rate (HR), respiratory sinus arrhythmia (RSA), pulse transit time (PTT), respiration rate (RSP) and skin conductance parameters (SCL, amplitude, rise time and number of SCRs) were analyzed for rest baseline and stimulation conditions. Analysis of the overall pattern of reaction indicated that autonomic response to tactile stimulation wasmanifested in a form of moderate HR acceleration, RSP increase, RSA decrease (lowered vagal tone), decreased PPT and increased electrodermal activity (increased SCL, several SCRs) that reflects general sympathetic activation. Parietal EEG effects (on contra-lateral side to stimulated hand) were featured by short-term alpha-blocking, slightly reduced theta and significantly increased delta and enhanced fast beta activity with few variations across stimuli. The main finding of the study was that most and least preferred textures exhibited significant differences in autonomic (HR, RSP, PTT, SCR, and at less extent in RSA and SCL) and electrocortical responses (delta, slow and fast alpha, fast beta relative power). These differences were recorded both in passive and active stimulation modes, thus demonstrating reproducibility of distinction between most and least emotionally preferred tactile stimuli, suggesting influence of psychological factors, such as emotional property of stimulus, on physiological outcome. Nevertheless, development of sufficiently sensitive and reliable template for classification of emotional responses to tactile stimulation based on physiological response pattern may require more extensive empirical database.

Passive and Active Touch of Fabrics: Psychophysiological Responses Modulation by the Emotional Preference of Touched Textures

Estate Sokhadze,Im Gap Yi,Kyung Hwa Lee,Jin Hun Sohn 한국감성과학회 1998 감성과학 Vol.1 No.2

자동차 경적소리에 대한 심리생리학적 반응 비교

( Estate Sokhadze ),민윤기 ( Yoon Ki Min ),손진훈 ( Jin Hun Sohn ),정인승 ( Inseung Chung ),( Moon Jae Jho ) 한국감성과학회 1999 춘계학술대회 Vol.1999 No.-

Automobile horn``s psychoacoustic characteristic and significance as anaturalistic signal of danger makes it a valuable auditory stimulus to study such psychophysiological responses as startle, orienting and defense reactions. However, comparison and differentiation of physiological responses to commercially available horns is a complicated task due to small contrast of technical features of horns and influence of such processes as habituation on physiological outcome with increased number of auditory stimulation trials. In the study on 10 college students we performed comparative analysis of tonic and phasic reactivity of physiological responses mediated by autonomic nervous system in order to identify role of habituation and decrement of autonomic responsivity, as well as possibility to differentiate subjectively most and least preferred and subjectively more appropriate horns according to physiological manifestations. It was showed that electrodermal and cardiovascular reactivity have concurrent patterns of adaptation to repeated stimulation, namely skin conductance variables habituated, cardiac reactivity failed to show signs of habituation, while vascular component of response were facilitated demonstrating marked sensitization. Differentiation of Physiological responses to horns with respect to their subjective rating scores was possible, however electrodermal reactivity was effective only at the first block of trials, while phasic and tonic cardiovascular reactivity differentiate responses during whole course of experiment. There are discussed possible autonomic mechanisms involved in mediation of observed results.

Respiratory Sinus Arrhythmia: Methods of Measurement and Interpretations of Tonic and Dynamic Vagal Cardiac Drive Index in Psychophysiology of Emotions

( Estate M. Sokhadze ),( Jong Mi Lee ),( Mi Kyung Park ),( Jin Hun Sohn ) 한국감성과학회 2000 추계학술대회 Vol.2000 No.-

Beat-to-beat changes in heart period (heart period variability, HPV) are mediated by fluctuations in autonomic activity. Spectral analysis is used to quantify such fluctuations in the range of 0.15-0.40 Hz (high frequency, HF), which are influenced primarily by parasympathetic factors. These fluctuations are often referred to as RSA (respiratory sinus arrhythmia), the physiological phenomenon extracted by spectral analysis and other methods including histograms of heart rate (HR), deviations of HR etc. Respiratory sinus arrhythmia indexing with peak-to-valley method suggested by Grossman et al, (1987) yields a simple range statistic and is quantified on breath-by-breath basis, thus being quite sensitive and less dependent on recording time as compared to spectral analysis. It is strongly recommended to use at least 1 min epoch to asses HF component of HPV and at least 2 min for low frequency (LF) of HPV and even 5 min for valid clinical assessment. Peak-to-valley statistic is limited to RSA index only, but has its pragmatic advantages. Most important is possibility of its application for relatively small epoch analysis. We used short periods (20,30, 40 sec only) and off-line analysis of RSA using ECG and respiration curve this method of assessment and proved that this method is more practically effective. The RSA index was not so far dependent on respiration pattern differences and reflected actual vagal control of HR and were accompanied by low HR under some high stress conditions and in an aversive affective visual stimulation experiments. Another factor that might modulate cardiac chronotropic response is the interaction of sympathetic and parasympathetic inputs on sino-atrial (SA) node level, because responses to vagal influences are known to be proportional to ongoing sympathetic activity, that is so called accentuated antagonism. Since sympathetic outflow (increment of influences on SA) under negative emotions or stress was high in almost all physiological responses, vagal effects on HR could be therefore potentiated, leading to masking of output cardiac response seen in HPV, In the case of moderate sympathetic activation, on the other hand, autonomic interactions in cardiac control appear to be minimal. Thus RSA index appears to be an effective alternative method to assess and measure spectral HPV.

Modulation of the Time Course of Cardiac Chronotropic Responses During Exposure to Affective Pictures

( Estate M Sokhadze ),( Kyung Hwa Lee ),( Long Mee Lee ),( Long In Oh ),( Jin Hun Sohn ) 한국감성과학회 2000 춘계학술대회 Vol.2000 No.-

One of the most important topics in attentional and emotional modulation of cardiac responses is time course of cardiac chronotropic response. The reason lies in dual innervation of heart, which leads to occurrence of several phases of cardiac response during exposure to affective stimuli, determined by the balance of sympathetic and parasympathetic influences. Cardiac chronotropic reactivity thus represents QUlte effective measure capable to trace the moment when attending and orienting processes (i.e., sensory intake of stimulus) prime relevant behavioral response (i.e., emotion with approach or avoidance tendencies). The aim of this study was to find the time course of heart rate (HR) responses typical for negative (disgust, surprise, fear, anger) and positive (happiness, pleasant erotic) affective pictures and to identify cardiac response dissociation for emotions with different action tendencies such as "approach" (surprise, anger, happiness) and "avoidance" (fear, sadness, disgust). Forty college students participated in this study where cardiac responses to slides from Laps intended to evoke basic emotions (surprise, fear, anger, sadness, disgust, happiness, pleasant-erotic). Inter-beat intervals of HR were analyzed on every 10 sec basis during 60 sec long exposure to affective visual stimuli. Obtained results demonstrated that differentiation was observed at the very first 10 s of exposure (anger-fear, surprise-sad, surprise-erotic, surprise-happiness pairs), reaching the peak of dissociation at 30 s (same pairs plus surprise-disgust and surprise-fear) and was still effective for some pairs (surprise-erotic, surprise-sad) even at 50 s and 60 s. Discussed are potential cardiac autonomic mechanisms underlying attention and emotion processes evoked by affective stimulation and theoretical considerations implicated to understand the role of differential cardiac reactivity m the behavioral context (e.g., approach-avoidance tendencies, orienting-defense responses).

백색소음하에서 단어암기 및 재인검사 수행시의 경악 및 정향반사 특성: 스트레스/정서연구에의 시사점

( Estate Sokhadze ),이임갑 ( Imgap Yi ),박경진 ( Kyung Jin Park ),손진훈 ( Jin Hun Sohn ) 한국감성과학회 1999 춘계학술대회 Vol.1999 No.-

In current study on 8 college students there was examined modulation of eyeblink (as measured by integrated EMG of m.orbicularis oculi) and skin conductance response (SCR) to an acoustic startle probe (85 dB[A] white noise) by attending to task presented in auditory modality (to memorize words for further recognition) and entire performance of the word recognition test. Both eyeblink magnitude and SCR amplitude and rise time to startle probes were modified (larger magnitude of EMG peak, lower amplitude and shorter rise time of SCR) during attending to task as compared to performance on test. Results are interpreted n terms of modification of electrodermal and eyeblink components of startle and orienting reflexes by task characteristics (passive versus active efforts), attentional demands and aversiveness of experimental situation. However, eyeblink startle response manifested potentiation during attending to task, while SCR demonstrated attenuation. There are discussed implications of startle modulatioas a potentially sensitive probe of situational demands in stress research and also are considered prospects for further studies.

소음에 장기 노출되었을 때 나타나는 심리생리적 효과

( Estate Sokhadze ),최상섭 ( Sang Sup Choi ),이경화 ( Kyung Hwa Lee ),김연규 ( Yeon Kyu Kim ),손진훈 ( Jin Hun Sohn ) 한국감성과학회 1999 추계학술대회 Vol.1999 No.-

It is well known that a long-term exposure to a loud noise environment affects performance, since it distracts attention, and also is able to evoke stress accompanied by negative emotional states. The purpose of this study was to analyze dynamics of subjective and physiological variables during long-lasting (30 min) exposure to intensive white noise (85 dB[A]). Physiological signals on 23 college students were recorded by BIOPAC, Grass Neurodata systems and AcqKnowledge 3.5 software. Autonomic variables, namely skin conductance level (SCL), non-specific SCR number (N-SCR), inter-beat intervals in ECG (RR intervals), heart rate variability index (HF/LF ratio of HRV), respiration rate (RESP), and skin temperature (SKT) were analyzed on 5 min epoch basis. Psychological assessment (subjective rating of stress level) was also repeated on every 5 min basis. Regression and correlation analyses were employed to trace the time course of the dynamics of the subjective and autonomic physiological variables and their relationship. Results showed that intense noise evokes subjective stress with associated autonomic nervous system responses. However, it was shown that physiological variables endure specific changes in the process of exposure to loud white noise. Discussed are probable psychophysiological mechanisms mediating reactivity to long-term auditory stimulation of high intensity.

Selection of Autonomic Measures for the Psychophysiological study of Emotions in Ergonomics

Estate M. Sokhadze,Jin Hun Sohn 대한인간공학회 2000 대한인간공학회 학술대회논문집 Vol.2000-2 No.-

The Effects of Habituation and Sensitization on Psychophysiological Differentiation of Responses to Auditory Stimulation with Automobile Horns

Estate M. Sokhadze,Jin Hun Sohn 한국감성과학회 2000 감성과학 Vol.3 No.2

시각자극에 의해 유발된 스트레스 생리반응의 회복과정에 미치는 정서청각자극의 효과

( Estate Sokhadze ),이임갑 ( Im Gap Yi ),최상섭 ( Sang Sup Choi ),이경화 ( Kyung Hwa Lee ),손진훈 ( Jin Hun Sohn ) 한국감성과학회 1998 춘계학술대회 Vol.1998 No.-

Effects of the music and white noise on recovery of the autonomic and cortical responses evoked by aversive visual stimulation were analyzed in 20 subjects. It was suggested that the music is able to exert modulatory influence on the physiological activity resulted from exposure to unpleasant IAPS based stimuli. Spectral power of DDG, heart rate(HR)respiration rate (RSR) and electrodermal activity(EDA)were recorded and analyzed for each experimental condition. It was observed HR and RSR deceleration, increased EDA and electrocortical activation expressed in decreased alpha power and increase of delta activity ao occipital and frontal areas. Obtained results suggest that audutory stimulation both with pleasant and sad music lead to restoration of pre-stimulation activation levels of most physiological parameters during listenning to music and in post-stimulation period. White noise evoked short-term physiological responses typical for orienting reaction and quite distinct from changes produced by music. Available data to differentiate effeces among pleasant and sad music, due toqualitative similarities of physilolgical patterns, but suppert an assumption that music is capable to facilitate the process of recovery of physilolgical responses elicited by visual stimulation of negative valence, thus positively modulate post-stress state.