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introversion
A program (Pascalin). based on an IBM-PC/AT. was developed in order to analyse. display and store psychophysiological data acquired by a commercially available program (DASAT”‘). This program has been u5ed to analyae in detail the electrocardiogram (ECG) of animals (rat, cat) or humans. Examples of results will be given. Pascalin allows one to display each run of an experimental procedure using several options with great reliability. These options can be modified according to new signal characteriatic!, or retrieved from a standard set of data. Moreover ECG parameters and segments (ST. QT. .I of clinical interest can be analysed simultaneously with other autonomic signals such as electrodermal activity (EDA) and arterial blood pressure (BP). Then. results are downloaded to a commercially available Tpreadsheet software for off-line statistical analysis and graphic presentations.
THE USAGE OF ERP FOR CONTROL OF HUMAN AUDITORY SIGNAL DETECTION UNDER SLEEP DEPRIVATION
Laricsa G. Dikaya Inst. of Psychology
AS U.S.S.R..
Moscow.
U.S.S.R.
The paper presents the experimental study of psychophyciological mechanisms of signal detection with the help of ERP. The possibility of practical application of cognitive psychology data for control of the human sensory function is discussed: Ss detected tone signal on the noise background under 24. 48. 72 and 96 hours sleep deprivation. The close relations between of auditory ERP and behavioural HZ and P, components indices (d’ RT) in the wide range of detectable signals up to threshold level were found. It is suggested that the H, component reflects a trigger of the brain mechanism providing comparison of actual stimulus with sensory memory trace. The I’, component is treated a\ a reflection of the evaluation of detected signal significance.
BEREITSCHAFTSPOTENTIAL RELATED TO THE SUING RESULT OF VOLUNTARY ACTION
EN-
B. Dimitrov. A. Vankob and M. loffe ‘%. T. Gavrilenko and N. Gantche\, lnst Physiol. BulgAcadSci, Sofia. Bulgaria and .’ Inst VND Nr Neurophysiol, Moscow, U.S.S.R.
Biphasic sequential movement\ of flexion-extension in the metac;irpophalangrul thumb Joint were examined. Flexor EMG initiated electrical shock> were delivered over the median nen’c with IO~l ms delay: separate series consisted of
either a single shock or a tetanic train for 1 $. Intensity was individually adjusted at two different levels. There was a tendency for higher BP amplitudes in the train-provoking series; both BPS were also positively correlated for the two stimulus levels in those series. BP magnitudes were found to be independent of the stimulus level and the ability to overcome the externally imposed tetanic contraction.
HEMISPHERIC ASYMMETRY: ERP AND EXTRAVERSION/INTROVERSION
COMPONENTS
Dincheva E.. M. Abrashev and P. Lasarov Institute of Hygiene and Occupational Health.
Sofia. Bulgaria
The left-right distribution of the ERP components in extraverts and introvert< was studied. The oddball paradigm (rare/frequent probability 0.2/0.X) at two levels of discriminability was used: lOOO/ II00 Hz-‘easy’ and 1000/1030 Hz‘difficult’ task. In total 24 subjects were investigated. In respect of the Nl. N2 and P3 components an asymmetry was observed. In the easy task the latencies tended to bc shorter at C4 compared to C3 for both groups. The correlation coefficient of the left-right asymmetry was higher in introverts than in extraverts. The difficult task led to a decrease of the asymmetry of the N2 and P3 in extraverts. Similar results were found with amplitude. These task difficulty-related changes show that the functional hemispheric asymmetry is less expressed in introverts.
SELECTIVE ALPHA?-ADRENOCEPTOR NISTS AND AUTONOMIC FUNCTIONS
Margit Dhda and ES. Vizi Institute of Experimental Medicine.
Budapest.
ANTAGOIN CATS
Hungary
It has been shown that alpha’-adrenoceptors play an important role in regulation oi somato-autonomic reactions. By means of a highly selective alpha2-adrenoceptor antagonist, CH-3HO8.3. it has been demonstrated. that sympathetic outflow is tonically inhibited via stimulation of alpha2-adrenoceptars. In this study experiments were performed in lightly anaehthetized cats. Contractions of the nictitating membrane. pressor responses and reactions of the renal sympathetic cfferents were elicited by sciatic nerve stimulation. Low doses (0.05~0. I mg/ky) of alpha2-adrenoceptor agonists, clonidinc and xylazine. increased. but higher doses (0.1-0.2 mg/kgJ decreased the amplitude of the evoked reactions. The selective alpha2-a~lrenoccptor antagonist. CH-38081. antagonized the inhibitory effects of agonists studied, and given alone. potcntiated the reflex rcspon\es. In conclusion, (I ) selective alpha2-ndrenoceptor agonists
THE USAGE OF ERP FOR CONTROL OF HUMAN AUDITORY SIGNAL DETECTION UNDER SLEEP DEPRIVATION
Laricsa G. Dikaya Inst. of Psychology
AS U.S.S.R..
Moscow.
U.S.S.R.
The paper presents the experimental study of psychophyciological mechanisms of signal detection with the help of ERP. The possibility of practical application of cognitive psychology data for control of the human sensory function is discussed: Ss detected tone signal on the noise background under 24. 48. 72 and 96 hours sleep deprivation. The close relations between of auditory ERP and behavioural HZ and P, components indices (d’ RT) in the wide range of detectable signals up to threshold level were found. It is suggested that the H, component reflects a trigger of the brain mechanism providing comparison of actual stimulus with sensory memory trace. The I’, component is treated a\ a reflection of the evaluation of detected signal significance.
BEREITSCHAFTSPOTENTIAL RELATED TO THE SUING RESULT OF VOLUNTARY ACTION
EN-
B. Dimitrov. A. Vankob and M. loffe ‘%. T. Gavrilenko and N. Gantche\, lnst Physiol. BulgAcadSci, Sofia. Bulgaria and .’ Inst VND Nr Neurophysiol, Moscow, U.S.S.R.
Biphasic sequential movement\ of flexion-extension in the metac;irpophalangrul thumb Joint were examined. Flexor EMG initiated electrical shock> were delivered over the median nen’c with IO~l ms delay: separate series consisted of
either a single shock or a tetanic train for 1 $. Intensity was individually adjusted at two different levels. There was a tendency for higher BP amplitudes in the train-provoking series; both BPS were also positively correlated for the two stimulus levels in those series. BP magnitudes were found to be independent of the stimulus level and the ability to overcome the externally imposed tetanic contraction.
HEMISPHERIC ASYMMETRY: ERP AND EXTRAVERSION/INTROVERSION
COMPONENTS
Dincheva E.. M. Abrashev and P. Lasarov Institute of Hygiene and Occupational Health.
Sofia. Bulgaria
The left-right distribution of the ERP components in extraverts and introvert< was studied. The oddball paradigm (rare/frequent probability 0.2/0.X) at two levels of discriminability was used: lOOO/ II00 Hz-‘easy’ and 1000/1030 Hz‘difficult’ task. In total 24 subjects were investigated. In respect of the Nl. N2 and P3 components an asymmetry was observed. In the easy task the latencies tended to bc shorter at C4 compared to C3 for both groups. The correlation coefficient of the left-right asymmetry was higher in introverts than in extraverts. The difficult task led to a decrease of the asymmetry of the N2 and P3 in extraverts. Similar results were found with amplitude. These task difficulty-related changes show that the functional hemispheric asymmetry is less expressed in introverts.
SELECTIVE ALPHA?-ADRENOCEPTOR NISTS AND AUTONOMIC FUNCTIONS
Margit Dhda and ES. Vizi Institute of Experimental Medicine.
Budapest.
ANTAGOIN CATS
Hungary
It has been shown that alpha’-adrenoceptors play an important role in regulation oi somato-autonomic reactions. By means of a highly selective alpha2-adrenoceptor antagonist, CH-3HO8.3. it has been demonstrated. that sympathetic outflow is tonically inhibited via stimulation of alpha2-adrenoceptars. In this study experiments were performed in lightly anaehthetized cats. Contractions of the nictitating membrane. pressor responses and reactions of the renal sympathetic cfferents were elicited by sciatic nerve stimulation. Low doses (0.05~0. I mg/ky) of alpha2-adrenoceptor agonists, clonidinc and xylazine. increased. but higher doses (0.1-0.2 mg/kgJ decreased the amplitude of the evoked reactions. The selective alpha2-a~lrenoccptor antagonist. CH-38081. antagonized the inhibitory effects of agonists studied, and given alone. potcntiated the reflex rcspon\es. In conclusion, (I ) selective alpha2-ndrenoceptor agonists