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Introduction: Simultaneous EEG-fMRI registration is rapidly evolving and has received substantial attention. This technique provides precise information in both spatial and temporal domain. The biological basis of the EEG and fMRI signal is different which, on the one hand makes results interpretation more difficult but, on the other hand, gives more convincing arguments on the neural correlates of sensory and cognitive processes. In this paper we present an example of implementation of simultaneous EEG-fMRI registration for alpha rhythm source mapping., Material and Methods: 60 young males took part in this study. For the group analysis we selected 33 individuals to obtain homogenous group. Siemens Magnetom Trio 3T and 64-electrode SynAmp2 Neuroscan EEG system was applied. Participants took part in fMRI imaging which adapted arrest reaction study., Results: Averaged spectra amplitude distribution of alpha rhythm (8-13Hz) showed high activation in the occipito-parietal region and smaller but noticeable activity in the frontal area. FMRI results revealed activity in bilateral occipital lobe. Additional regions included the posterior cingulate gyrus, middle and superior frontal gyrus. Statistically significant areas with BOLD signal decrease were located in the temporal lobe and anterior cingulate gyrus., Conclusion: The obtained results indicate overlapping regions of the presented EEG outcomes and fMRI maps for alpha rhythm study. Simultaneous EEG-fMRI technique allows for registration of spontaneous EEG activity with both high temporal and spatial resolution. The alpha rhythm might reflect the extensive brain process involving the thalamo-occipito-frontal connections.

The visual and mathematical analysis (computer assisted) of the background cerebral activity in patients with vasomotor headaches, including common vasomotor headaches, Horton's headache and migrainous headache showed statistically significant fluctuations of the frequency of the background cerebral bioelectric activity only in patients with migrainous headaches. Of interest was the observed evident asymmetry of the alpha rhythm frequency. This indicates that the background bioelectric cerebral activity is arrhythmic and asymmetrical in patients with migrainous headaches.

A visual and computer-assisted analysis was made of basic brain biological function in 45 EEG recordings of alpha waves alone or mostly alpha waves. The study revealed abnormal frequency of alpha waves in patients with chronic alcoholism (60%) and in people chronically exposed to carbon disulphide (73.4%). The abnormalities most probably reflect dysfunction of the CNS.

In a material of 39 cases EEG investigations were carried out in patients with vertebrobasilar failure at rest and in different positions of the head. It was observed that EEG curves in cases of vertebrobasilar failure can be normal or may show different changes. Head movements caused changes in EEG curves in one-fourth of these cases but no correlation was demonstrated between the intensity of these changes and the intensity of clinical changes.

Using Siemens type II rheograph 100 subjects aged 18 to 28 years were investigated analysing averaged rheoencephalographic curves from 50 repetitions by means of a Neuro-Averager apparatus made by Biomedica, and Anops 10 Biological Computer. The trigger for averaging was the QRS complex in ECG of the investigated subject. The records were obtained in sitting and lying positions. All curves were divided into the following types: U waves, U--W waves and W waves; positive and negative curves were also separated. The segment between the peak of the main wave and the beginning of the dicrotic wave was subjected to a particularly careful analysis. Because of its shape and accessory waves occurring there they were divided into alpha and beta waves. In the group of W waves L waves were separated. In sitting position 70% of the waves belonged to group W and positive waves were observed in 98% of this group. In lying position W waves accounted for 61% and positive waves for 12%. The shape of REG wave reflects the haemodynamic conditions in a given area and is changed, similarly as these conditions, with a change in the position of the subject.

The authors describe the principles of operation of AR-3 frequency EEG analyser designed at the Medical Technique Centre in Białystok. The results of analysis of EEG curves by means of this analyser are presented and discussed. The results of frequency analysis obtained by means of this analyser may be presented in the form of the so-called index of activity as suggested by the authors.

The authors analysed electroencephalographic findings in 36 patients with Horton's headache (cluster headaches). It was found that EEG findings in Horton's headache are usually normal and show considerable stability. Slight EEG changes observed in a low number of cases were usually similar to those observed in the general population. The analysis of bioelectric activity of the brain in patients with this headache suggests an extracerebral mechanism of this disease.

The author reviews the pertinent literature and the results of own investigations in migraine. EEG changes in migraine are observed in nearly 50% of cases during attacks as well as in the periods free of pains. Most investigations were done in the periods between attacks. The H response characteristic of migraine was found by the author in 25% of cases only. Focal changes were present in 30% of cases. They were not related to the side of the pain, its duration and the form of migraine. Seizure activity was never observed. The author regards isolation of the so-called dysrhythmic form of migraine as not justified. EEG changes suggest--according to the author--that migraine is a primary cerebral and only secondarily a vascular disorder.

The effect of Anginin was assessed in 10 patients with cerebrovascular diseases. Anginin was administered in daily doses of 1.5 g. during a mean time of 5.25 months. The duration of follow-up before, during and after treatment was 2 years. A favourable effect of Anginin was observed on such symptoms as dizziness, disturbances of recent memory, mental fatiguability, difficulties in concentration and irritability. EEG investigations demonstrated a rise in the index of alpha waves, increased frequency and amplitude of alpha waves, and normalization of tracings in cases with pathological abnormalities. The basic laboratory investigations failed to reveal any significant changes. Side effects included transient dyspeptic symptoms were in 5 patients.