Akemi Saito

Differences in quantitative EEG between frontotemporal dementia and Alzheimer’s disease as revealed by LORETA

OBJECTIVE To determine the electrophysiological characteristics of frontotemporal dementia (FTD) and the distinction with Alzheimers disease (AD). METHODS We performed analyses of global field power (GFP) which is a measure of whole brain electric field strength, and EEG neuroimaging analyses with sLORETA (standardized low resolution electromagnetic tomography), in the mild stages of FTD (n = 19; mean age = 68.11 ± 7.77) and AD (n = 19; mean age = 69.42 ± 9.57) patients, and normal control (NC) subjects (n = 22; mean age = 66.13 ± 6.02). RESULTS In the GFP analysis, significant group effects were observed in the delta (1.5-6.0 Hz), alpha1 (8.5-10.0 Hz), and beta1 (12.5-18.0 Hz) bands. In sLORETA analysis, differences in activity were observed in the alpha1 band (NC > FTD) in the orbital frontal and temporal lobe, in the delta band (AD>NC) in widespread areas including the frontal lobe, and in the beta1 band (FTD > AD) in the parietal lobe and sensorimotor area. CONCLUSIONS Differential patterns of brain regions and EEG frequency bands were observed between the FTD and AD groups in terms of pathological activity. SIGNIFICANCE FTD and AD patients in the early stages displayed different patterns in the cortical localization of oscillatory activity across different frequency bands.

EEG Global Field Power Spectrum Changes After a Single Dose of Atypical Antipsychotics in Healthy Volunteers

Effects of four novel atypical antipsychotic drugs (olanzapine, perospirone, quetiapine, and risperidone) on scalp-recorded multi-channel EEGs were compared with two conventional antipsychotic drugs (chlorpromazine and haloperidol) and placebo in 14 healthy male volunteers. All subjects went through seven sessions. In each session, EEGs were recorded before and 2, 4 and 6 hours after drug administration. Global Field Power (GFP) in delta frequency band (1.5-6 Hz) increased around the time of peak serum concentration of quetiapine and risperidone compared to baseline. The increase of GFP in delta activity after quetiapine was significantly prominent in comparison to two other atypical antipsychotic drugs, perospirone and olanzapine, as well as to typical antipsychotic drugs, chlorpromazine and haloperidol (p<0.05). The increase in GFP of delta after risperidone was more prominent in comparison to after haloperidol (p<0.05). The greater sedative effects after quetiapine and risperidone may reflect the high affinity to A1 and H1 receptor bindings of these drugs. According to Low Resolution Electromagnetic Tomography (LORETA), olanzapine increased the delta in the posterior region indicating a frontal shift of brain activity, suggesting that olanzapine may be useful against negative symptoms in schizophrenics.

Levodopa challenge test and 123I-metaiodobenzylguanidine scintigraphy for diagnosing Parkinson's disease

To explore the possibility of a generally applicable tool for the immediate diagnosis of Parkinsons disease (PD) in its early stage, we compared the sensitivity and specificity of an acute levodopa challenge test with that of 123I‐metaiodobenzylguanidine (MIBG) myocardial scintigraphy.

PO9.4 Global EEG Descriptors for Changes Induced by Antipsychotics

Background: Alzheimer disease is most common form of dementia and one of complicated neurodegenerative diseases. Quality of life of AD patient significantly lowed due to sleep disturbance. The sleep disturbance is mostly associated direct or indirectly with the appearance of theta waves. Appearance of this wave suggests a shift of wave discharge from physiological to pathological pattern. To study pathophysiological effects of theta wave appearance with relation to its physiological discharge site mostly hippocampus. Methods: It is a review to study pathophysiological effects of increased delta and theta waves during sleep in AD with relation to physiological site for theta wave discharge i.e. hippocampus. Results: The sleep of Alzheimer’s disease (AD) patients is often disturbed by medications, depression, circadian rhythm changes and sleep disorders. The patients of AD exhibit brain wave changes during sleep. These changes are present in parieto-temporal and frontal regions and are more prominent in REM sleep and consisted primarily in an increase in absolute delta and theta activities, and a decrease in absolute alpha and beta activities. The concentrations of delta sleep-inducing peptide (DSIP)-like (DSIP-LI) is significantly decrease in moderate to severe AD. This effects the delta wave mild decrease discharge and shift to increase theta discharge as relative compensation. Conclusions: In this review, effects of increased theta and altered delta wave discharge during sleep in patients of AD is discussed. The understanding of increased theta wave physiological and pathological effects in the process of AD with relation to sleep are important for improved quality of life of patient.