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421 EEG correlates of mental decline in mild dementia
Abstracts
421 EEG CORRELATES MILD DEMENTIA
/International
OF MENTAL
Journal
DECLINE
IN
A.F. Iznak*, S.I. Gavrilova, I.V. Kolykhalov, N.V. Chayanov, S.E. Zhigulskaya, A.G. Vasilieva and IF. Roschina Mental Health Research Centre, 34, Kashirskoye shausse, Moscow 115522, Russia The objectives of the study were to reveal the spectral and topographical EEG correlates of mental decline in elderly patients with mild dementia of different origin. METHODS. 60 patients (age 46-87 years) with mild dementia (MMSE scores = 18-26) represented three clinical groups: presenile Alzheimer’s disease (n = 21, mean age 61.1 + 6.8 years) and senile dementia of the Alzheimer’s type (n = 20, mean age 75.2 + 5.0 years) met NINCDS/ADRDA criteria, and vascular dementia (n = 19, mean age 72.1+ 3.0 years) met NINCDS/AEREN criteria. EEG spectral density values in M, F3, F4, F8, T3, C3, C4, T4, T5, P3, P4, T6, 01, 02 referred to ipsilateral ear lobes, in delta (2-4 Hz), theta-l (4-6 Hz), theta-2 (6-8 Hz), alpha-l (S-10 Hz) and alpha-2 (lo-12 Hz) EEG bands, as well as clinical ratings (MMSE) and neuropsychological tests performance scores were subjected to factorial analysis (principal components method, oblimin rotation) using BMDPC package. RESULTS. Some factors of the factorial structure obtained linked both clinical (MMSE) and neuropsychological and EEG parameters. Thus diminishing of MMSE in mildly demented patients was associated mainly with decrease in performance of neuropsychological tests concerned to the IIIrd and IInd functional blocks of the brain (by A.R.Luria). From the other hand, decrease of both integrated parameter of general mental decline (MMSE) and efficacy of performance of separate neuropsychological tests were associated with the EEG slowing, namely with increase of delta, theta-l, theta-5 and alpha-l spectral density, while correlated negatively with the alpha-2 amount. According to the factor loading values, the main contribution to the higher cortical function impairment was brought by the change of brain functional state reflected in increase of amount of the low-frequency theta (theta-l) EEG band. The data obtained suggested these changes to be related both to decrease of regional cerebral blood flow and/or to limbic disinhibition in elderly demented patients.
422 EYE-HEAD-HAND COORDINATION IN PARKINSON’S DISEASE
DISODERS
B.Kh. Baziyan’, L.A. Chigaleichik’ and Ilya E. Dmitriev’* ‘Brain Research Institute, RAMS, Obukha lane, 5, Moscow, 103064, Russia *Moscow Institute of Physics and Technology, Moscow, Russia Twenty six patients with Parkinson’s disease by means of original technique developed in Brain Research Institute of
of Psychophysiology
30 (1998)
95-271
163
RAMS were studied. During the experimental procedure patients were asked to follow target steps by their gaze. Horizontal saccadic eye movements, head and hand position were recorded by electrooculographic technique and by precise potentiometers attached to lightweight helmet and traveling handle respectively. An increase of both movements’ latencies and durations in comparison with ones of healthy subjects was observed. Some patients tended to avoid head movements during gaze shifts. Multistep movements were present. Neurophysiological mechanisms of movement disorders and some practical applications of developed technique such as assessment of clinical therapy or rehabilitative training procedure are discussed.
423 ELECTROPHYSIOLOGICAL DYSLEXIA
DIAGNOSTICS
OF
Z. Kubova, M. Kuba, J. Kremlacek Departments of Physiology and Pathophysiology, Faculty of Medicine, Charles University, Simkova 870, Hradec kralove 500 01, Czech Republik Some recent studies on dyslexia (impairment of reading skills despite normal intelligence, social environment, visual acuity and motivation) have suggested a selective abnormality in the magnocellular visual pathway. To verify this hypothesis, we investigated motion-onset visual evoked potentials (VEPs) (predominantly testing magnocellular system) as well as pattern-reversal VEPs (presumably testing the parvocellular system) in 20 dyslexics and 20 controlsi(both with mean age of 10.0 years). Whereas the latencies and amplitudes of the main positive peak of pattern-reversal VEPs did not differ between the dyslexic and control group, the motion specific negative peak of motion-onset VEPs was significantly (p < 0.001) delayed in dyslexics, displaying no difference in its amplitude. Our results confirm a selective magnocellular pathway disorder in dyslexics and indicate that the motiononset VEPs might serve as an objective method for an early diagnosis of dyslexia.
424 III - VI - VII CRANIAL NERVE DISORDERS IN A PATIENT SUFFERING FROM HEMORRHAGE IN BRAINSTEM: BLINK REFLEX AND BAEP’s STUDY E. Caggia*, A. Scrofani, F. Lanaia, V. Fassari, E.A. Corso, G. Campo and A. Grass0 Neurological Science Institute, University of Catania, Viale Andrea Boria, 6, Catania 95126, Italy The evidence of wide lesions in cranial nerves nuclei is an unusual event in clinical experience.We describe one patient with right and left oculomotor disorder (levator palpebrae
421 EEG CORRELATES MILD DEMENTIA
/International
OF MENTAL
Journal
DECLINE
IN
A.F. Iznak*, S.I. Gavrilova, I.V. Kolykhalov, N.V. Chayanov, S.E. Zhigulskaya, A.G. Vasilieva and IF. Roschina Mental Health Research Centre, 34, Kashirskoye shausse, Moscow 115522, Russia The objectives of the study were to reveal the spectral and topographical EEG correlates of mental decline in elderly patients with mild dementia of different origin. METHODS. 60 patients (age 46-87 years) with mild dementia (MMSE scores = 18-26) represented three clinical groups: presenile Alzheimer’s disease (n = 21, mean age 61.1 + 6.8 years) and senile dementia of the Alzheimer’s type (n = 20, mean age 75.2 + 5.0 years) met NINCDS/ADRDA criteria, and vascular dementia (n = 19, mean age 72.1+ 3.0 years) met NINCDS/AEREN criteria. EEG spectral density values in M, F3, F4, F8, T3, C3, C4, T4, T5, P3, P4, T6, 01, 02 referred to ipsilateral ear lobes, in delta (2-4 Hz), theta-l (4-6 Hz), theta-2 (6-8 Hz), alpha-l (S-10 Hz) and alpha-2 (lo-12 Hz) EEG bands, as well as clinical ratings (MMSE) and neuropsychological tests performance scores were subjected to factorial analysis (principal components method, oblimin rotation) using BMDPC package. RESULTS. Some factors of the factorial structure obtained linked both clinical (MMSE) and neuropsychological and EEG parameters. Thus diminishing of MMSE in mildly demented patients was associated mainly with decrease in performance of neuropsychological tests concerned to the IIIrd and IInd functional blocks of the brain (by A.R.Luria). From the other hand, decrease of both integrated parameter of general mental decline (MMSE) and efficacy of performance of separate neuropsychological tests were associated with the EEG slowing, namely with increase of delta, theta-l, theta-5 and alpha-l spectral density, while correlated negatively with the alpha-2 amount. According to the factor loading values, the main contribution to the higher cortical function impairment was brought by the change of brain functional state reflected in increase of amount of the low-frequency theta (theta-l) EEG band. The data obtained suggested these changes to be related both to decrease of regional cerebral blood flow and/or to limbic disinhibition in elderly demented patients.
422 EYE-HEAD-HAND COORDINATION IN PARKINSON’S DISEASE
DISODERS
B.Kh. Baziyan’, L.A. Chigaleichik’ and Ilya E. Dmitriev’* ‘Brain Research Institute, RAMS, Obukha lane, 5, Moscow, 103064, Russia *Moscow Institute of Physics and Technology, Moscow, Russia Twenty six patients with Parkinson’s disease by means of original technique developed in Brain Research Institute of
of Psychophysiology
30 (1998)
95-271
163
RAMS were studied. During the experimental procedure patients were asked to follow target steps by their gaze. Horizontal saccadic eye movements, head and hand position were recorded by electrooculographic technique and by precise potentiometers attached to lightweight helmet and traveling handle respectively. An increase of both movements’ latencies and durations in comparison with ones of healthy subjects was observed. Some patients tended to avoid head movements during gaze shifts. Multistep movements were present. Neurophysiological mechanisms of movement disorders and some practical applications of developed technique such as assessment of clinical therapy or rehabilitative training procedure are discussed.
423 ELECTROPHYSIOLOGICAL DYSLEXIA
DIAGNOSTICS
OF
Z. Kubova, M. Kuba, J. Kremlacek Departments of Physiology and Pathophysiology, Faculty of Medicine, Charles University, Simkova 870, Hradec kralove 500 01, Czech Republik Some recent studies on dyslexia (impairment of reading skills despite normal intelligence, social environment, visual acuity and motivation) have suggested a selective abnormality in the magnocellular visual pathway. To verify this hypothesis, we investigated motion-onset visual evoked potentials (VEPs) (predominantly testing magnocellular system) as well as pattern-reversal VEPs (presumably testing the parvocellular system) in 20 dyslexics and 20 controlsi(both with mean age of 10.0 years). Whereas the latencies and amplitudes of the main positive peak of pattern-reversal VEPs did not differ between the dyslexic and control group, the motion specific negative peak of motion-onset VEPs was significantly (p < 0.001) delayed in dyslexics, displaying no difference in its amplitude. Our results confirm a selective magnocellular pathway disorder in dyslexics and indicate that the motiononset VEPs might serve as an objective method for an early diagnosis of dyslexia.
424 III - VI - VII CRANIAL NERVE DISORDERS IN A PATIENT SUFFERING FROM HEMORRHAGE IN BRAINSTEM: BLINK REFLEX AND BAEP’s STUDY E. Caggia*, A. Scrofani, F. Lanaia, V. Fassari, E.A. Corso, G. Campo and A. Grass0 Neurological Science Institute, University of Catania, Viale Andrea Boria, 6, Catania 95126, Italy The evidence of wide lesions in cranial nerves nuclei is an unusual event in clinical experience.We describe one patient with right and left oculomotor disorder (levator palpebrae