Межрегиональная психофизиологическая ассоциация (Россия) Interregional Psychophysiological association (Russia)

1. Межрегиональная психофизиологическая ассоциация (Россия) Interregional Psychophysiological association (Russia)

Доклад был представлен
на всемирном конгрессе психофизиологов

2. Cross-correlation ANALYSIS of EEG AND ASYMMETRY of α-RHYTHM in CHILDREN aged 6-7 YEARS after achievement of the OBJECTIVE  

Cross-correlation ANALYSIS of EEG
AND ASYMMETRY of α-RHYTHM in CHILDREN aged 6-7 YEARS
after achievement of the OBJECTIVE
Kuznetsova T. G.,
Bulgakova O. S.,
Popova T. V.,
Koryukalov Y. I.,
Volkova I. P.,
Gorbachevа M. V.

3.

Контакты: +79046017095
[email protected]
mpfarussia.ru

4.

The body is a complete self-regulating system that seeks to preserve the
constancy of the internal environment – homeostasis – at all levels and in
all systems. At the same time, purposeful behavior of any organism, being
an integral part of its life. Reflection of information characteristics of the
achieved goal (speed, time, etc.) is associated with the cognitive
component of the subject's activity, and the estimated side of the goal
(utility, necessity, etc.) is reflected in the activation of the emotion system.
That is why, first of all, when achieving the goal, emotional reactions are
most clearly manifested – joy with the rapid achievement of the desired
goal and avoidance up to failure with a long and difficult achievement.
Cognitive characteristics of the achieved goal are manifested at higher
levels of self-regulation-endocrine, neurohumoral, vegetative, Central, etc.
Comparative studies of human and anthropoid behavior in achieving the
goal revealed that high speed and short time to achieve it activated the
system of positive emotions. Change of speeds and increase of time of
achievement was reflected in discrete replacement of positive emotions
by activation of system of approximate reactions and concentration and
gradual increase of negative emotions. It was found that these reactions
were clearly correlated with the overall dynamics of heart rate variability,
its stress index (IN) and brain biopotential rearrangement.

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Unfortunately, there is no clear idea about the reflection of emotions in the EEG of adults [1, 6] and there
are practically no ontogenetic studies in this direction. At the same time, according to clinical studies it is
known that the negative emotional state is formed by the right hemisphere, and the positive – by the left.
Hence the objective of our study – the attempted search of bioelectrical correlates of goal-directed
behavior while the activation of emotions in children in ontogeny. Of particular interest is the analysis of αrhythm, reflecting not only the maturity of the Central nervous system of a child of preschool age, but also
the manifestation of his emotional reactions.

6.

• Method of research
• Used the technique of approaching target (MPI), which is the conveyor belt
length 1000 mm. At the far end has placed the goal object. The speed of
movement of the target was set by the researcher and varied in the range
from 250 to 5 mm/ s, and the subject on the command " Attention, work!"I
started the device by means of the button which is before it.
• In the course of the study, a video was recorded to analyze the behavioral
reactions of self-regulation with parallel registration of EEG from 10 leads:
Fp1, Fp2, F3, F4, P3, P4, T3, T4, O1, O2, located according to the
international scheme 10-20, monopolar with a combined ear electrode on
the 21-channel amplifier unit of the company "mitzar EEG" (St. Petersburg)
and a personal computer. EEG processing was carried out in the program
"MitsarWinEEG".
• Considered changes of cross-correlation relations of the EEG, the dynamics
of the frequencies of α-rhythm and the asymmetry of its distribution across
the electrodes for a period of at least 60 s for each of the presented speeds
with the following averaging over the group of subjects.
• Statistical analysis of the results was carried out on the basis of StatSoft
Statistika 6.0 software package using nonparametric Wilcoxon T-test.
Differences at the level of at least P<0.05 were considered significant.

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• Results and discussion
• Previously, it was found that in all Primate subjects, regardless of age,
species and sex (children, adults, chimpanzees), the change in the speed of
the approaching target was associated with discrete activation of
modulating systems: emotional reactions, concentration and indicative
reflex.
• As a rule, the achievement of the test object approaching at speeds of 250
and 125 mm / s occurred against the background of a calm emotionally
positive response to the situation.
• The movement of the object approaching at speeds from 50 to 25 mm / s,
activated protective behavioral reactions of self-regulation of passive
avoidance (averting gaze, turning away from the installation, etc.) and was
accompanied by a tendency to reduce the time of tracking a moving object.
A further reduction in the target velocity to 10 and 5 mm / s increased the
manifestation of negative reactions and significantly (p=0.002) reduced the
tracking time compared to previous speeds.
• At the same time, the distribution of cross-correlation links of EEG was
similar, both in a calm state with open eyes (GO), and in response to a
decrease in the speed of the object from 250 to 5 mm/s (except for the
speed of 50 mm/s), despite the opposite in physiological significance
emotional coloring of high and low speeds (Fig. 1).

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P.1. Changing the distribution of
correlations with a decrease in the rate
of approximation of the target.
Designation: topogram distribution of
correlations between the examined
areas of the brain. Dotted lines - from
15% to 19% of links, black thin – from
20% to 29% of links, black fat – more
than 30% of links.
In these situations, the most often interrelated were
symmetrical front-motor (17% -23%), left-sided
parietal-occipital (16% -24%) and right-sided temporal
– parietal-occipital (16% - 26%) brain zones, with long
interhemispheric frontal-parietal connections (19% 28%), the so-called "cognitive axis".
Attention was drawn to the fact that in the state when
the TARGET is approaching at a speed of 5 mm/s, the
distribution of correlations was the same, both in
configuration and in the correlation coefficient r from
0.4 to 0.6. In addition, the achievement of an object
approaching speeds of 250, 125, 25 and 10 mm/s,
was also similar in configuration, but the correlation
coefficient increased r from 0.6 to 0.8.
In the situation of reaching the target approaching at a
speed equal to 50 mm/s, the system of indicative
reaction was activated. Psychologically, the test
subjects perceived this speed close to high speeds,
but visually the target-the object was moving much
slower, which led to a mismatch in the system of
achieving the goal (there was uncertainty of the
situation).

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Misalignment in the system has led to the desynchronization of the correlation of
EEG, toward a meaningful restructuring of brain potentials and the increased
correlation between the individual zones in all tested frequency bands.
Unlike other speeds of approach of the purpose, in this situation not only the
quantity of right-sided temporal-parietal-occipital (from 30% -40%) and left-sided
parietal-occipital communications (45%) remained and/or increased, the number of
interhemispheric frontal-parietal (from 20 to 40%) doubled, but also their
correlation coefficient increased to 0,8-1,0 in all frequency ranges.
At the same time, the appearance of new (r > 0.4-0.6) hemispheric frontal-frontal,
frontal-occipital (up to 25%) and frontal-temporal (25%) connections drew
attention.
With a decrease in the rate of reaching the object and a change in emotional color
from positive to negative dynamics of α-rhythm in the range (8-13 Hz) in children
did not change significantly, which is consistent with the data of foreign authors,
obtained in adults with "passive" viewing of emotional films.
At the same time, further analysis of the obtained facts revealed an interesting
nuance of changes in the asymmetry of the α-rhythm depending on the conditions
for achieving the goal in the sub-bands.
It is known that the α-rhythm is finally formed at the age of 15-17 years, but by the
age of 7 there is a low-frequency α – rhythm (no more than 8 Hz), which does not
yet have "fusiform" modulations and gradient of incidence from the occipital to
frontal zones and is divided into sub – bands: low – frequency-from 7.0 to 8.5 Hz,
mid-frequency-from 8.75 to 9.75 Hz and high-frequency-from 10.0 to 13.5 Hz.

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• However, the study found that 77% of children with low-frequency (from
7.0 to 8.5 Hz) range of α-rhythm observed similar to the background, a
significant right-hand asymmetry in almost all leads, regardless of the
activation of modulating systems associated with the speed of reaching
the object (see table: 1, 4, 7 and 10 columns).
• In 11.5% of children with the average frequency (from 8.75 to 9.75 Hz) αrhythm revealed a significant left-sided asymmetry in the initial state (GO)
and remained at the achievement of the goal accompanied by both
positive and negative emotional response (see table: 2, 5 and 11 columns,
respectively). When the target was reached at 50-25 mm/s, there was no
asymmetry in the situation of uncertainty (column No. 8).
• Another 11.5% of children with high-frequency (from 10.0 to 13.5 Hz) αrhythm also had a significant left-sided asymmetry in the initial state,
which remained regardless of the emotional perception of the
approaching object, determined by the speed of its achievement (see
table: 3, 6, 9 and 12 columns).
• The overall pattern for the latter two groups of children was the preserve
of the asymmetric activity of α-rhythm, relative to an initial condition in
the anterior regions of the left hemisphere and the disappearance of it in
the rear sections of the same hemisphere when it reaches the object
approaching from all the lower speeds.

11.

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Thus, the obtained facts of distribution of α-rhythm in EEG of children 6-7
years, characterizing the level of maturity of the cerebral cortex, indicate
that in most children of this age α-rhythm is not yet formed and has a lowfrequency range, in less is at the stage of completion or has already
completed its formation, which is consistent with the work of children's
psychophysiologists.
Conclusion
• It is shown that in children 6-7 years old, as well as in adults, the increased
activity of α-rhythm in the range of 8-13 HZ in the associative zones of the
right hemisphere and its asymmetric distribution in the parietal-temporal
regions is a common mechanism in the perception of emotionally
significant stimulus regardless of age.
In children, unlike adults, the revealed asymmetry of the distribution of αrhythm in the sub-bands is not associated with the emotional significance
of the stimulus and indicates only the lack of maturity of their Central
nervous system.

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Спасибо за внимание