[Functional activity of the brain depending on the degree of severity occupational noise-induced hearing loss]. / Funktsional'naya aktivnost' golovnogo mozga v zavisimosti ot stepeni vyrazhennosti professional'noi neirosensornoi tugoukhosti.

Research objective identification of the peculiarities of indicators of audiological examination, registration of somatosensory induced potentials (SSSP), level of constant potential (LCP) and neuropsychological testing in persons of flight composition (LLS) of civil aviation exposed to intra-cabin noise, depending on the degree of expression of professional neurosensory noise (ONIHL). PATIENTS AND METHODS: Thresholds of acoustical sensitivity, levels of perception of shepotny, informal conversation, UPP, characteristic of SSVP, neuropsychological features at 45 patients with easy degree of PNST (LONIHL) and at 50 - with moderate degree of ONIHL (UONIHL) are studied. RESULTS: LCP in the left frontal (Fs), central dark (Pz) leads increased in persons with ONIHL, and the inter-peak interval of the N13-N20 characterizing the central conduct time increased. The FAB, unlike the LONIHL, is characterized by deterioration of cognitive activity in the form of easily pronounced decrease of visual memory functions, expressive speech, FAB scale value indicating priority dysfunction of frontal, dark-occipital lobes, subcortical cerebral structures. CONCLUSION: Neurofunctional markers in UONIHL are the reduction of the indicators of the interfamily relations on the frontal department, conceptual thinking, visual image memory, expressive speech, MMSE and FAB tests, the increase of LCP in the left temporal, central dark, occipital right central N13-N20, inter-peak N25.

[Comparative characteristic of cognitive impairment at alcoholic and discirculatory encephalopathy]. / Kharakteristika kognitivnykh narushenii pri alkogol'noi i distsirkulyatornoi entsefalopatii.

OBJECTIVE: Identification of features of cognitive impairment at patients with alcoholic and discirculatory encephalopathy. MATERIAL AND METHODS: 30 patients with the alcoholic encephalopathy (AE) and 32 - with discirculatory encephalopathy (DE) participated in research. To patients conducted clinical examination, a computer electroencephalography with determination of cognitive evoked potentials, neuropsychological testing. RESULTS: General and distinguishing characters of a clinical picture, cognitive deficiency, disturbances in the emotional and personal sphere at patients with encephalopathies alcoholic and vascular genesis are established. CONCLUSION: It is established that a basis of a clinical picture of encephalopathy of various genesis are the cognitive disturbances (CD) and an asthenic syndrome, of AE it is characteristic hyposthenic, and at DE - hyper - and hyposthenic syndromes. Changes of bioelectric activity of a brain at DE had primary localization in occipitoparietal departments of a brain, at AE - in temporal and occipitoparietal assignments. Disorder of categorial thinking, the long-term memory, reciprocal coordination, manual gnosis indicating dysfunction by a frontal, parietal lobe of the left hemisphere, a hippocampus, a corpus collosum are provided to CD in DE and AE patients. It is established that distinguishing characters of CD in AE and DE patients are values of indexes Δ-, ß1-, ß2-rhythms, the indicators characterizing the impressive speech, volume of visual figurative memory, level of severity of hypochondria.

[Interrelation of rates of a biological aging with neurophysiological features at patients with professional neurointoxications].

In the hospital conducted studying of functional activity of a brain of patients with professional neurointoxications for the purpose of detection of neurophysiological features of formation of the accelerated rates of biological aging at the working, being affected neurotoxicant is carried out. During the research it is shown that rates of aging at patients with professional neurointoxications on average in 85% of cases have premature character. The general signs of defeat of structures of a brain at professional intoxication are defined by mercury irrespective of a disease stage at the accelerated biological aging. For toxic impacts on a nervous system the characteristic, uniting sign distinguishing from the accelerated rates of aging of other etiology is the indicator characterizing augmentation of a latence of peak of P2 of the visual caused potentials. Based on the analysis of the received correlations it is set that in case of professional neurointoxications permanent disorganization of the functional activity of a brain in the form of cortical and subcortical violations of sensor regulatory systems of a brain is a consequence of chronic influence of vapors of metal mercury and a complex of toxic substances and the reason of the accelerated biological aging.

[Clinical and neurophysiological peculiarities of health disorders in workers in dependence on the vinyl chloride exposure load].

Results of the clinical and neurophysiological examinations of 42 workers with operating history at the chemical plant exposed to vinyl chloride (VC) are presented. The purpose of research was the identification ofpeculiarities of clinical manifestations and disorders of the functional activity of the brain in workers at the vinyl chloride production, with taking into account the exposure toxic load (ETL). There were made clinical and electroencephalographic examinations with the detection of cognitive evoked potentials (CEP) and statistical analysis of results with the use of the Mann-Whitney U-test, Fisher's F-test, calculation of Spearman's correlation coefficient. The features in clinical picture of the pathology of the nervous system were detected in the form of asthenic disorders with cognitive impairment and autonomic dysfunction syndrome. There was established the increase in the cognitive impairment rate (p = 0.03), the decline in a-EEG activity (p = 0.01) and the worsening of indices of the amplitude (p = 0.011) and latency (p = 0,05) of CEP in extremely high level of ETL in comparison with same indices in the group with moderately high ETL. In the first group there was revealed a statistically significant exceedance of the frequency of hypertension - by 1.6 times, skin diseases - by 9 times, chronic subatrophic rhino-pharyngitis by 1.4 times in comparison with cases from the second group. In the group with moderately high level of ETL there was established the statistically significant inverse correlationship between the ETL and the index of P300 amplitude from the left side (r = -0.38, p = 0.019) and in the group with extremely high level ETL - between ETL and index of the ß2 - rhythm (r = - 0.73, p = 0.0008).

[Cognitive impairment in a toxic lesion of the brain].

OBJECTIVE: To identify features of cognitive impairment in patients with toxic (mercury or alcohol) encephalopathy. MATERIAL AND METHODS: The study involved 36 patients with chronic mercury intoxication and 30 people with chronic alcoholism. A control group included 30 age-matched healthy men who were not exposed to toxic substances and alcohol abuse. All patients underwent neuropsychological examination, which involved a set of neuropsychological Luria rated memory status, praxis, gnosis and speeches. MMSE and FAB were used for the diagnosis of moderate cognitive impairment. Computer electroencephalography and cognitive evoked potentials method were used as well. RESULTS AND CONCLUSION: The diffuse brain injury in toxic encephalopathy (alcohol and mercury) on EEG, and according to the results of neuropsychological testing was identified. Changes in analytical and synthetic thinking, audio-verbal, long-term, visual memory, reciprocal coordination, finger gnosis, impressive speech were observed in mercury encephalopathy. Functional failure of the frontal lobe and the premotor area of the left hemisphere were revealed in alcoholic encephalopathy.

[Cognitive disorders in patients with chronic mercury intoxication].

To assess severity of cognitive disorders in chronic mercury intoxication, the authors performed claster and discrimination analysis of neuropsychologic and neurophysiologic research data from workers exposed to mercury during long length of service, from patients with early and marked stages of chronic mercurial intoxication. Cognitive disorders in chronic mercurial intoxication have three severity degrees, in the light degree disorders patients demonstrate lower amplitude of cognitive evoked potentials, poor long-term memory and associative thinking. Moderate cognitive disorders are characterized by decreased visual, long-term memory, concentration of attention, poor optic and spatial gnosis. Marked cognitive disorders with chronic mercurial intoxication present with more decreased long-term, short-term, picturesque memory, poor intellect, optic and spatial gnosis and associative thinking.

[Neuropsychologic traits in individuals with chronic exposure to mercury at work].

The article deals with diagnostic peculiarities of neuropsychologic traits in individuals with previous exposure to industrial neurotoxic chemicals. Pilot studies demonstrated brain disorders characteristic for toxic (mercurial) and vascular (discirculatory) encephalopathies, justified necessity of neuropsychologic approach in occupational therapeutic diagnosis. The authors presented results of suggested scheme of neuropsychologic prompt screening aimed to reveal higher psychic functional disorders in individuals with occupational neurointoxications.

[Main aspects of classification and course of occupational neurointoxication with toxic chemical complex in firemen].

The article covers results of long-standing research of peculiarities of psychoneurologic syndromes formation in firemen during distant period after intoxication with toxic chemical complex. The authors studied course, peculiarities of early manifestations of neurointoxication. Analysis of the data obtained helped to classify occupational intoxication with toxic chemical complex, considering the clinical peculiarities.

[Toxic encephalopathies in distant post-contact period of occupational neurointoxications (clinical and experimental studies)].

The article covers results of long-standing research on clinical peculiarities and course of toxic encephalopathy in distant period of occupational neurointoxications, on main concepts and pathogenetic steps of formation and progress of toxic encephalopathy. Through investigation covered firemen after exposure to complex of toxic chemicals and patients in post-contact period of chronic mercury intoxication. Modelling of chronic inhalation of metallic mercury vapors was performed.

[Prognosing the development of toxic encephalopathy after exposure to a complex of chemical substances in fire fighters].

92 fire fighters with the toxic encephalopathies and with no signs of this disease have been examined using the electrophysiological and medical-psychological procedures. The resulting study indices have been processed using a discriminant analysis. The probability of the toxic encephalopathy development in the subjects with occupational exposure to a complex of the harmful chemical substances has been calculated using the diagnostic coefficients and a prognostic index.

[Medical-psychological consequences of exposure to fire factors among the fire fighters-liquidators at the company "IRKUTSKCABLE"].

This work has shown that a complex of toxic substances to which the fire fighters-liquidators organisms may be exposed can exert the neurotropic effects forming the negative medical-psychological consequences a long-term period after the fire. They are expressed as the progressive processes of the nervous system diseases including the common brain disorders and the middle structure dysfunctions, the accelerated biological aging rates, emotional-personality sphere disintegration, attention-mnemic sphere disorders, all this prevents from the further social adaptation among the sufferers.

[Late psychopathological manifestation of professional neurointoxications].

A study of 47 firemen exposed to a complex of toxic substances while putting out fire and 46 subjects with chronic mercury intoxications was carried out 5-10 years after the exposure to toxic substances. Along with clinical psychiatric examination, neuropsychological testing was conducted. Non-specificity of mental disorders, polymorphism and progressive development were found. Psychoorganic syndrome with secondary neurotic disturbances proved to be a core feature of mental disorders. It is emphasized that neuropsychological examination or usage of neuropsychological methods during a psychiatric examination are important for practical diagnosis of exogenous organic mental disorders, especially for outpatient examination of corresponding occupational groups.

The ALTEA/ALTEINO projects: studying functional effects of microgravity and cosmic radiation.

The ALTEA project investigates the risks of functional brain damage induced by particle radiation in space. A modular facility (the ALTEA facility) is being implemented and will be operated in the International Space Station (ISS) to record electrophysiological and behavioral descriptors of brain function and to monitor their time dynamics and correlation with particles and space environment. The focus of the program will be on abnormal visual perceptions (often reported as "light flashes" by astronauts) and the impact on retinal and brain visual structures of particle in microgravity conditions. The facility will be made available to the international scientific community for human neurophysiological, electrophysiological and psychophysics experiments, studies on particle fluxes, and dosimetry. A precursor of ALTEA (the 'Alteino' project) helps set the experimental baseline for the ALTEA experiments, while providing novel information on the radiation environment onboard the ISS and on the brain electrophysiology of the astronauts during orbital flights. Alteino was flown to the ISS on the Soyuz TM34 as part of mission Marco Polo. Controlled ground experiments using mice and accelerator beams complete the experimental strategy of ALTEA. We present here the status of progress of the ALTEA project and preliminary results of the Alteino study on brain dynamics, particle fluxes and abnormal visual perceptions.

ALTEA: anomalous long term effects in astronauts. A probe on the influence of cosmic radiation and microgravity on the central nervous system during long flights.

The ALTEA project participates to the quest for increasing the safety of manned space flights. It addresses the problems related to possible functional damage to neural cells and circuits due to particle radiation in space environment. Specifically it aims at studying the functionality of the astronauts' Central Nervous Systems (CNS) during long space flights and relating it to the peculiar environments in space, with a particular focus on the particle flux impinging in the head. The project is a large international and multidisciplinary collaboration. Competences in particle physics, neurophysiology, psychophysiology, electronics, space environment, data analyses will work together to construct the fully integrated vision electrophysiology and particle analyser system which is the core device of the project: an helmet-shaped multi-sensor device that will measure concurrently the dynamics of the functional status of the visual system and passage of each particle through the brain within a pre-determined energy window. ALTEA is scheduled to fly in the International Space Station in late 2002. One part of the multi-sensor device, one of the advanced silicon telescopes, will be launched in the ISS in early 2002 and serve as test for the final device and as discriminating dosimeter for the particle fluences within the ISS.

The ALTEA facility on the International Space Station.

The ALTEA project studies the problems related to possible functional damage to the Central Nervous System (CNS) due to particle radiation in space environment. The project is a large international and multi-disciplinary collaboration. The ALTEA instrumentation is an helmet-shaped multi-sensor device that will measure concurrently the dynamics of the functional status of the visual system and the passage of each particle through the brain within a pre-determined energy window. ALTEA is scheduled to fly in the International Space Station in February 2003. One part of the multi-sensor device, one of the advanced silicon telescopes, will be launched in the ISS in early 2002 and serve as test for the final device and as discriminating dosimeter for the particle fluences within the ISS.

[Clinical and functional aspects of adverse effects of toxic substance complexes in firefighters]. / Kliniko-funktsional'naia kharakteristika neblagopriiatnogo deistviia kompleksa toksicheskikh veshchestv na organizm likvidatorov pozhara.

The study covered influence of combined toxic chemicals on fire extinguishers. Acute exposure of respiratory and peripheral nervous systems was demonstrated. Consequences of the exposure were proved to include polyneuropathies, neuroses and other health disorders.