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Theta synchronization in EEG of infants during feeding
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changings in sentence typing cycle, which are estimated on the basis of motor activity changes, with the slow potentials dynamic we can suppose the following. As related to the action of separate letter typing different stages of learning are characterized with different amount of stages of changes specificity of the set of systems in that interval; the difference in the number of the potentials reflects these processes. The comparison of amplitudes positivities in the interval of sentence typing shows that at the first stage in the interval of typing of two adjacent letters many intersystem changings take place which are connected with searching actions, but the total change of one set of systems by another one occurs only at the moment of typing. When skill performance is automatized total intersystem changing occurs only at the bounds of the words. While typing other letters only a concretization of the set of systems which realizes a certain stage occurs. Appearance of negative waves according to the sentence typing and stable reproduction of negative waves related with the words end separate letters typing demonstrate high specificity of sets of systems realizing these stages. The order of appearance and the mutual organization of negative waves in the process of learning may to some extent reflect the “history” of the formation and then the final structure of subject’s memory, related to the given motor skill. References
Aleksandrov I.O., Maksimova N.E. (1985) Functional meaning of Pa,,,,Psychol. journ., V. 76, N 3: 86-95 (in Russian) Bezdeneshznykh B.N., Pashina ACh. (1987) The structure of EEG-activity during the sentence typing. In: EEG and neuronal activity in psychophysiological studies. M. Science (in Russian). P. 185-197. Shvyrkov V.B. (1985) Psychophysiological study of subjective reflection structure. Psychol. joum., V. 76, N 3: 22-37 (in Russian)
Walter (1950), Maulsby (1971) and Nikitina et al. (1985) have shown that emotional stimuli could substantially change the background of EEG activity evoking synchronization in theta band. This interesting phenomenon has not yet been studied in details in infants. Studying the development of the feeding behaviour in infants we often met with that phenomenon in our polygraphic recordings. This communication deals with following aspects of the theta synchronization in infants during the first 6 months of life: 1) the situation, 2) the development, 3) the individuality. Material 20 fullterm healthy infants which stayed during the
first six months of life in a small well-established residential unit of our institute were followed. The infants were admitted to our unit from social reasons. The mothers stayed with their infants for longer time in 10 cases and these infants were breast fed till 8 to 12 weeks. Method The feeding behaviour of the infants was studied in
four standard successive situations: 1. before feeding, 2. with pacifier, 3. during feeding, 4. after feeding. The examinations were done in an experimental box during a morning feeding always in three successive days at the age of 2, 10, 18 and 26 weeks. The mother or a nurse had the infant on her knees during the examination. Behavioural patterns were recorded by two observers from an adjacent room and concurrently videorecording was taken. Simultaneously a polygraphic recording of the EEG, electrooculogram, respiration, sucking, swallowing and vocalisation was made. One minute period from each situation was analysed in detail. EEG activity from the leeds C3-P3 and C3-C, was quantified and parameters “theta index” and “mean amplitude” were statistically tested. Results I. h&ence
THETA SYNCHRONIZATION FANTS DURING FEEDING
IN EEG OF IN-
K. Paul, J. Dittrichova Institute for Care of Mother and Child Prague, Czechoslovakia
offeeding situation. The visual analysis of the recordings gave an impression that the EEG activity in the situation “during feeding” differed from the other situations. The quantification revealed differences that were statistically significant. “Theta index” was higher during feeding than before feeding in the 18th week (pcO,Ol) as well as in the 26th week
346 (pcO,Ol). “Mean amplitude” was significantly higher in the situation “during feeding” than “before feeding” in all age periods with exception of the 10th week ( 2nd w.: p
Milk drinking in small infants evokes changes in the background of EEG activity consisting in the increase of rhythmicity in theta band and in the heightening of amplitude. The analysis of behaviouml and other polygraphic parameters showed that these changes were related neither to the process of falling asleep nor to the rhythmic sucking activity. We suppose that they are related to the positive emotional state elicited by food intake. This type of EEG activity can be observed at first at the age of 10 to 18 weeks which is probably connected with the maturation of the central nervous system. The intensity of this activity may be lowered by novelty. In the course of adaptation the intensity of
theta synchronization increases gradually. There were marked individual differences in the incidence of theta synchronization. These differences persisted with considerable stability throughout the first six months of life. References
Nikitina, G.M. et al. (1985) Central organization of emotional reactions during the first year in infants. Abstr. Sympos. Neuroontogen. IV. p. 83 , Praha Maulsby, R.L. (1971) An illustration of emotionally evoked theta rhythm in infancy: hedonic hypersynchrony. Electroenceph. clin. Neurophysiol. 31 157165 Walter, W.G. (1950) Normal rhythms - their development distribution and significance. In: D.Hill and G.Paar (eds): Electroencephalography: A symposium in its various aspects. Mac Millan , N.Y. 203-212
CHANGES OF HEART RATE IN COLLEGE STUDENTS IN CONNECTION WITH EXAMINATION SITUATION K. Paulfk, B. VaSina Teachers’ Training College, Regional Institute of Hygiene, Ostrava, Czechoslovakia The demands that college studies make on a student are not distributed evenly throughout his studies at a college or university. It is well known that periods of relative calm alternate with periods that are, due to the demands they make, very exacting for many students and often result in stress. We devoted our attention to the reaction of the students’ organisms to the examination situation as revealed by the changes of the heart rate. We were observing 60 students of a teachers’ training college in order to ascertain: 1) the heart frequency at rest, after a short relaxation 24 - 26 hours before the examination, and the changes of this frequency in the course of the examination in one subject by one examiner. We divided the time of the examination proper into the following basic stages: a) immediately after the student was given the questions,
changings in sentence typing cycle, which are estimated on the basis of motor activity changes, with the slow potentials dynamic we can suppose the following. As related to the action of separate letter typing different stages of learning are characterized with different amount of stages of changes specificity of the set of systems in that interval; the difference in the number of the potentials reflects these processes. The comparison of amplitudes positivities in the interval of sentence typing shows that at the first stage in the interval of typing of two adjacent letters many intersystem changings take place which are connected with searching actions, but the total change of one set of systems by another one occurs only at the moment of typing. When skill performance is automatized total intersystem changing occurs only at the bounds of the words. While typing other letters only a concretization of the set of systems which realizes a certain stage occurs. Appearance of negative waves according to the sentence typing and stable reproduction of negative waves related with the words end separate letters typing demonstrate high specificity of sets of systems realizing these stages. The order of appearance and the mutual organization of negative waves in the process of learning may to some extent reflect the “history” of the formation and then the final structure of subject’s memory, related to the given motor skill. References
Aleksandrov I.O., Maksimova N.E. (1985) Functional meaning of Pa,,,,Psychol. journ., V. 76, N 3: 86-95 (in Russian) Bezdeneshznykh B.N., Pashina ACh. (1987) The structure of EEG-activity during the sentence typing. In: EEG and neuronal activity in psychophysiological studies. M. Science (in Russian). P. 185-197. Shvyrkov V.B. (1985) Psychophysiological study of subjective reflection structure. Psychol. joum., V. 76, N 3: 22-37 (in Russian)
Walter (1950), Maulsby (1971) and Nikitina et al. (1985) have shown that emotional stimuli could substantially change the background of EEG activity evoking synchronization in theta band. This interesting phenomenon has not yet been studied in details in infants. Studying the development of the feeding behaviour in infants we often met with that phenomenon in our polygraphic recordings. This communication deals with following aspects of the theta synchronization in infants during the first 6 months of life: 1) the situation, 2) the development, 3) the individuality. Material 20 fullterm healthy infants which stayed during the
first six months of life in a small well-established residential unit of our institute were followed. The infants were admitted to our unit from social reasons. The mothers stayed with their infants for longer time in 10 cases and these infants were breast fed till 8 to 12 weeks. Method The feeding behaviour of the infants was studied in
four standard successive situations: 1. before feeding, 2. with pacifier, 3. during feeding, 4. after feeding. The examinations were done in an experimental box during a morning feeding always in three successive days at the age of 2, 10, 18 and 26 weeks. The mother or a nurse had the infant on her knees during the examination. Behavioural patterns were recorded by two observers from an adjacent room and concurrently videorecording was taken. Simultaneously a polygraphic recording of the EEG, electrooculogram, respiration, sucking, swallowing and vocalisation was made. One minute period from each situation was analysed in detail. EEG activity from the leeds C3-P3 and C3-C, was quantified and parameters “theta index” and “mean amplitude” were statistically tested. Results I. h&ence
THETA SYNCHRONIZATION FANTS DURING FEEDING
IN EEG OF IN-
K. Paul, J. Dittrichova Institute for Care of Mother and Child Prague, Czechoslovakia
offeeding situation. The visual analysis of the recordings gave an impression that the EEG activity in the situation “during feeding” differed from the other situations. The quantification revealed differences that were statistically significant. “Theta index” was higher during feeding than before feeding in the 18th week (pcO,Ol) as well as in the 26th week
346 (pcO,Ol). “Mean amplitude” was significantly higher in the situation “during feeding” than “before feeding” in all age periods with exception of the 10th week ( 2nd w.: p
Milk drinking in small infants evokes changes in the background of EEG activity consisting in the increase of rhythmicity in theta band and in the heightening of amplitude. The analysis of behaviouml and other polygraphic parameters showed that these changes were related neither to the process of falling asleep nor to the rhythmic sucking activity. We suppose that they are related to the positive emotional state elicited by food intake. This type of EEG activity can be observed at first at the age of 10 to 18 weeks which is probably connected with the maturation of the central nervous system. The intensity of this activity may be lowered by novelty. In the course of adaptation the intensity of
theta synchronization increases gradually. There were marked individual differences in the incidence of theta synchronization. These differences persisted with considerable stability throughout the first six months of life. References
Nikitina, G.M. et al. (1985) Central organization of emotional reactions during the first year in infants. Abstr. Sympos. Neuroontogen. IV. p. 83 , Praha Maulsby, R.L. (1971) An illustration of emotionally evoked theta rhythm in infancy: hedonic hypersynchrony. Electroenceph. clin. Neurophysiol. 31 157165 Walter, W.G. (1950) Normal rhythms - their development distribution and significance. In: D.Hill and G.Paar (eds): Electroencephalography: A symposium in its various aspects. Mac Millan , N.Y. 203-212
CHANGES OF HEART RATE IN COLLEGE STUDENTS IN CONNECTION WITH EXAMINATION SITUATION K. Paulfk, B. VaSina Teachers’ Training College, Regional Institute of Hygiene, Ostrava, Czechoslovakia The demands that college studies make on a student are not distributed evenly throughout his studies at a college or university. It is well known that periods of relative calm alternate with periods that are, due to the demands they make, very exacting for many students and often result in stress. We devoted our attention to the reaction of the students’ organisms to the examination situation as revealed by the changes of the heart rate. We were observing 60 students of a teachers’ training college in order to ascertain: 1) the heart frequency at rest, after a short relaxation 24 - 26 hours before the examination, and the changes of this frequency in the course of the examination in one subject by one examiner. We divided the time of the examination proper into the following basic stages: a) immediately after the student was given the questions,