タグ「EEG」
Author: Loganovsky K.N., Yuryev K.L.
Reference: J. Neuropsychiatry Clin. Neurosci. — 2004. — Vol. 16, № 1. — P. 70–82.
Keywords: qEEG, neurophysiological markers, left fronto-temporal dominant frequency reduction
Abstract: Cross-sectional quantitative electroencephalogram (qEEG) study (1996—2001) among Chernobyl accident survivors, who had confirmed acute radiation sickness and were irradiated in dose of 1—5 Gy, revealed the neurophysiological markers of ionizing radiation. Neuropsychological markers were: left fronto-temporal dominant frequency reduction; absolute δ-power lateralization to the left (dominant) hemisphere; relative δ-power increase in the fronto-temporal areas; absolute θ-power decrease in the left temporal region; absolute and relative α-power diffusive decrease, which may reflect cortico-limbic dysfunction lateralized to the left, dominant hemisphere, with the fronto-temporal cortical and hippocampal damage. Quantitative electroencephalogram proposed for differentiation of radiation and nonradiation brain damages and as a new biological dosymetry method. High radiosensitivity of the brain, neocortex, and dominant hemisphere higher radiosensitivity are discussed.
URL: http://neuro.psychiatryonline.org/article.aspx?articleID=101854
Author: Loganovsky K.N., Yuryev K.L.
Reference: J. Neuropsychiatry Clin. Neurosci. — 2001. — Vol. 13, № 4. — P. 441–458
Keywords: EEG, cortical-limbic overactivation, organic brain damage
Abstract: Prospective conventional EEG study was carried out 3-5 and 10-13 years after the Chernobyl accident (1986) in patients who had acute radiation sickness and in emergency workers in 1986 (“liquidators”). Control groups comprised healthy volunteers; veterans of the Afghanistan war with posttraumatic stress disorder; veterans with mild traumatic brain injury; and patients with dyscirculatory encephalopathy. In 3-5 years after irradiation, there were irritated EEG changes with paroxysmal activity shifted to the left frontotemporal region (cortical-limbic overactivation) that were transformed 10-13 years after irradiation toward a low-voltage EEG pattern with excess of fast (beta) and slow (delta) activity together with depression of alpha and theta activity (organic brain damage with inhibition of the cortical-limbic system). Quantitative EEG is likely to be very informative for investigation of dose-effect relationships.
URL: http://neuro.psychiatryonline.org/article.aspx?articleid=101516
Author: Loganovsky K., Perchuk I., Nechayev S.
Reference: International Journal of Psychophysiology. — 2010. — Vol. 77, № 3. — P. 0204.
URL: http://www.deepdyve.com/lp/elsevier/brain-mapping-of-quantitative-eeg-before-and-after-exposure-to-low-FsZXyIfF08
Author: Igumnov S.
Reference: Activitas Nervosa Superior Rediviva. — 2009. — Vol. 51, № 1–2. — P. 55–60.
Keywords: BEA, Belorus, borderline EEG, IQ
Abstract: OBJECTIVE: The study examined the formation of bioelectric activity (BEA) of the brain of 250 children at the age of 6–7, 10–12 and 15–16 years from regions highly contaminated by Chernobyl fallout, who were irradiated in the prenatal period at the time of the Chernobyl accident in 1986. These children were compared with a control group of 250 children of the same age from non-contaminated areas of Belarus.
METHODS: The examination included visual and computerized analysis of EEG as well as psychiatric examination and assessment of intellectual level.
RESULTS: In the both groups of children at the age of 6–7 the dominant were the variants of age norms (46.4% vs 44.8%; p=0.592) and synchronized (borderline) EEG (26.4% vs 28.0%; P=0.763). Quite noticeable was the relevant frequency of the slow type of EEG (19.2% vs 18.4%; p=0.820) as well as paroxysmal activity (8.0% vs 8.8%; p=0.830) in the both groups. At the age of 15–16 in the both groups we registered relevant decrease of index of θ- and δ-activity. The slow type of EEG in most cases was transformed into the age norm and synchronized type of EEG. The correlation analysis showed that the intellectual level of children (IQ) estimated by Wechsler Intelligence Scale (WISC-III) was in the direct proportion to spectral power of α-diapason in frontal lobes of the brain (r=0.38 in the both groups). Mental deficiency of children of the both groups was accompanied by the decreased level of the coherency of α-diapason. When comparing the results of BEA research with the dosimetric data we found no relevant correlation of these indices. The children with different EEG types did not demonstrate any relevant differences of medium doses of antenatal exposure.
CONCLUSIONS: The revealed changes of BEA of the brain show distinct age dependency. Their frequency in the cohort of persons exposed to antenatal irradiation did not have relevant differences from that in control group. (full text available on web)
URL: http://www.rediviva.sav.sk/51i12/55.pdf
Author: Zhavoronkova L. A., Lavrova T. P., Belostocky A. V., Kholodova N. B., Skoryatina I. G., Voronov V. P.
Reference: ЖУРНАЛ ВЫСШЕЙ НЕРВНОЙ ДЕЯТЕЛЬНОСТИ ИМ. И.П. ПАВЛОВА (Journal of higher nerbous activities named after I.P.Pavlov), 2006
Keywords: EEG, space-frequency parameter, cognitive performance
Abstract: Changes in frequency and space parameters of the EEG coherence evoked by cognitive performance were analyzed in 13 healthy subjects and participants of the Chernobyl clean-up. In healthy subjects, the EEG coherences in the alpha and beta frequency bands were significantly increased during arithmetic count and during visuospatial performance. Each test was characterized by regionally-specific features. Chernobyl patients demonstrated a global decrease in the EEG coherence predominantly in the alpha and beta frequency bands, especially in the frontal cortical areas. Patients with various pathological EEG patterns demonstrated specific impairment of EEG parameters. In patients with a “flat” EEG pattern, the EEG coherence predominantly decreased in the frontal associative areas, especially during arithmetic calculation. In patients with a “hypersynchronous” EEG pattern, the decrease in the EEG coherence was most pronounced in the parietal associative areas, especially during the visuospatial performance. The revealed impairments of the EEG coherence reactivity may be a reflection of disorders of the intracortical and corti-cosubcortical interaction and can result from the remote postradiation brain atrophy, especially, of cortical structures.
URL: http://elibrary.ru/item.asp?id=9193503
