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Biomedical subjects

J Spunda

Publications and source records attributed to J Spunda.

10 recordsLinked to original sources

Computer programs suitable for processing behavioral data characterized by alternation of two states.

A program system is described which is suitable for processing behavioral and psychophysiological data characterized by alternation of two states (the transition between which is instantaneous). It is adapted for a LINC D.E.C. computer and is composed of a control program and several system programs computing different statistics and performing necessary input and output operations with the data.

Behavior

A device for evaluation of the dominant component of the EEG activity.

A setup composed of a bioanalyser and additional electronic circuits is described allowing to measure the instantaneous frequency and amplitude of the dominant component of EEG activity. Besides recording the above values on paper by means of the EEG apparatus, functions of probability density of both the amplitude and the frequency of EEG activity are estimated on-line during preadjusted time intervals, and displayed on the screen of the bioanalyser. The mutual relationship between instantaneous EEG amplitude and frequency can be expressed in two-dimensional histograms displayed on a memory scope. The system described is suitable for laboratories having no possibility to use general purpose computer on-line.

Animals

Thiopental anaesthesia and the acid-base balance in the blood of experimental dogs.

An analysis of basic parameters representative of the acid-base balance was made in arterial blood samples from 140 clinically healthy dogs, under a general intravenous Thiopental anaesthesia. The following mean values +/- S.E.M. were obtained: pH = 7.33 +/- 0.01; pCO2 = 47.16 +/- 0.95; base excess = -2.12 +/- 0.27; buffer base = 46.63 +/- 0.37. The results showed a prevalent trend of lower values of pH, base excess and buffer base and higher values of pCO2 than those found commonly in human clinical practice. Special attention was paid to the respiratory component of the acid-base balance (ABB) revealing certain undesirable side effect of Thiopental anaesthesia.

Acid-Base Equilibrium

A technique for on-line classification of evoked potentials into two groups according to subjective interpretation of the stimulus.

A technique is described for on-line classification of evoked potentials (EPs) into distinct groups for separate averaging according to a criterion available after the beginning of the EPs. It is suitable for analysing psychophysiological correlations (relationship between EPs and subjective perception). The system consists of a slightly modified NTA 512 B (Hungarian) average response computer (however, any CAT-computer-like device can be used in a similar way) and of an additional device. It can be used in all cases when the number of subjective judgements according to which EPs have to be classified can be limited to two (or three, when, by slightly changing the system, all quarters of memory are used).

Computers

Evoked responses induced by random polygonal pattern presentation.

An experiment is described which was designated to test the assumption that visual EEG evoked response waveshapes in human beings may be influenced by the presentation of random shapes differing in level of their similarity and in angular position. A clear-cut difference between the blank flash and the patterns which might be determined by the presence of contours was observed. However, neither differences in EEG evoked responses referred to the shape nor to the angular position of the polygons were found.

Electroencephalography