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Biomedical subjects

E S Dmitrieva

Publications and source records attributed to E S Dmitrieva.

At least 19 recordsLinked to original sources
PubMed1990

Inhibition of neutrophil-mediated lysis of syngeneic erythrocytes by components of blood serum and peritoneal fluid.

Experiments are reported in which it is shown that murine blood serum and peritoneal fluid contain compounds of high molecular mass that inhibit the lysis of murine erythrocytes caused by syngeneic neutrophils, and that these inhibitors directly affect the neutrophils. Neutrophil sensitivity to phorbol 12-myristate 13-acetate (PMA) changes in the presence of these high-molecular-mass serum components, whereas their sensitivity to opsonized zymosan does not.

Animals↗
PubMed1977

[Invariability of stimulus recognition by dolphins].

The echo-location characteristics were studied in dolphins with the aid of transformation of stimuli not altering the reception characteristics in analysing systems. The dolphin locator was shown to be able to single out a class of equivalent in respect to certain transformations echo-signals. The probability of the target recognition is invariable in respect to transformations of homothetic type and module transformations, i.e. the principle of invariability spreads over the work of dolphin's auditory analyser in active regimen too.

Animals↗
PubMedDate not supplied

Invariability of auditory perception with respect to frequency--time signal transformations in the dolphin Tursiops truncatus.

The characteristic of hearing in the dolphin Tursiops truncatus were investigated by the method of motor-feeding conditioned reflexes under conditions of frequency--time signal indeterminancy with background noise. It was shown that the effectiveness of auditory detection of tone--pulse signals is invariant with respect to Doppler and shift signal transformations, while the number of waves is a characteristic parameter of the auditory system.

Animals↗
PubMedDate not supplied

[Spatial analysis of tonal superthreshold signals in dolphins].

Hearing characteristics under the conditions of spacial indetermination of overthreshold tonic signal were studied on dolphins Tursiops truncatus by the method of motordigestive conditional reflexes. High efficiency of spacial analysis on the frequencies 5, 20, 80, 100 kHz was shown. The criterium of relative loss of information in the channel was used for evaluating integral index of efficiency of dolphin spacial hearing.

Animals↗
PubMedDate not supplied

[Efficiency of dolphin auditory perception in relation to time characteristics of the signal].

Experimental data are presented on evaluating the efficiency of auditory perception of the dolphin Tursiops truncatus of tonal signals of different duration and of the fixed energy on the background of Gauss obstacle. The dependence of percepting properties on time characteristics of the signal are stated. A comparative analysis of the efficiency of dolphin auditory system with that of the coordinated filter is carried out. Biological receiving systems are shown to be adaptive. The self-tuning linits of the dolphin auditory system at a given level of the possibility of correct detection are determined.

Acoustic Stimulation↗
PubMedDate not supplied

[The formation of interhemispheric asymmetry in human ontogeny during the perception of emotions in normal speech and in stuttering].

Age peculiarities of functional brain asymmetry in perception of emotional information of speech have been revealed. It was shown that the age of 4-7 years is most important for formation of this asymmetry in emotional perception. It is in this age that functional reorganization of perception in stuttering children is observed. These data indicate that correction of emotional activity in stutterers should be made at early periods of their life.

Aging↗
PubMedDate not supplied

[THe age-related characteristics of interhemispheric asymmetry during the perception of verbal information by stuttering children].

Age peculiarities of functional brain asymmetry in perception of emotional information of the speech have been revealed. It was shown that the age of 4-7 years is the most important period in ontogenesis for the age dynamics of functional brain asymmetry in perception of emotions. It is in this particular age that functional reorganization of perception in stuttering children is observed. The revealed disturbances in functional brain asymmetry indicate that correction of emotional activity in stutterers should be made during early periods of ontogenesis.

Adolescent↗
PubMedDate not supplied

[Ontogenetic aspects of individual characteristics of functional brain asymmetry in the perception of emotions].

Studies have been made on individual variations in perception of speech emotional information by 7-16-year children. Significant differences between subjects from various age groups were found concerning the correct recognition of emotions, the degree of brain asymmetry and domination type. The exactness of emotional recognition increases with age, while the degree of asymmetry becomes lower, the right hemisphere domination becoming more stable in processing of speech emotional information. With age, individual type of asymmetry turns to the specific one, reflecting asymmetry formation during evolution.

Adolescent↗
PubMedDate not supplied

[Sex differences of functional lateralization in the perception of verbal and emotional information in ontogeny].

Experimental data show certain differences between men and women in perception of verbal and emotional information. They are revealed in the ability of correct perception of definite kind of information, in the degree of brain functional asymmetry in perception of the given information, in prevalence of domination type. The character of sex differences in functional asymmetry changes little with the age; quantitative correlations of the coefficient of asymmetry diminish with the age.

Adolescent↗
PubMedDate not supplied

[Age-related characteristics of human perception of emotions in speech and in singing].

Monoaural presentation (in sequence to the left and right ears) of speech and vocal-musical phrases with different emotional content (joy, grief, anger, fear, indifference) has been made to children ageing between 7 and 16 years. These passages were performed by professional actors or singers. Absolute differences in the probability of correct identification of different emotions were obtained. They are maximal for fear and anger, being minimal for joy. Left ear preference to perception of emotions both in speech and in singing is already formed in 7-8 years old children.

Adolescent↗
PubMedDate not supplied

[Interhemispheric brain asymmetry in speech perception by persons of different age groups and the "effect of directional attention"].

Using dichotic tests, studies have been made on the degree of functional asymmetry of the brain with respect to perception of verbal information in 3-50 years old subjects. Significant age variations were found in the volume of the percepted speech information. Interhemispheral differences in speech perception, which reveal themselves in higher perception of the right ear as compared to the left one, are more evident in children under 10 years. Significant influence of the "effect of voluntary and involuntary attention" of the subjects was noted on the degree of asymmetry of dichotic speech perception, this influence alleviating the intrinsic functional asymmetry of the brain.

Adolescent↗
PubMedDate not supplied

[Lateralization characteristics in the perception of speech in noise by children of different age groups].

The comparative investigation in ontogenesis of the noise immunity of child sensorial perception of two kinds of bioacoustical information (the emotional one being more evolutionary old and the semantic one being evolutionary younger) has shown that the perception effectiveness of these kinds of information depends on the noise level, the age of a child and the kind of information. The perception of semantic information is not provided with the reliable mechanisms of signal identification from noise even to the age of 16 while such mechanisms for perception of emotional information are formed in ontogenesis by the age of 14 and they are associated with the activity of the right hemisphere.

Adolescent↗