Power spectral density changes in the EEG during mental arithmetic and eye-opening
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The effect of mental arithmetic (standard multiplication, with eyes closed) and eye-opening on the power spectral density of the EEG (recorded bipolarly from occipital and parietal regions) have been compared. The EEG was recorded on magnetic tape from normal subjects, (medical students) in a constant environment and subsequently analysed by an analogue computer (Noratom Instrument for Statistical Analysis and Computation, ISAC).
Absolute measurements made from 15 subjects with eyes closed have shown that peaks of power at 10 Hz vary from 9 to 46 μV2 per Hz. Qualitatively, suppression of power at 10 Hz is greater due to eye-opening than mental arithmetic.
Analysis of pooled power spectral density functions from 11 subjects showed that the effect of eye-opening differed significantly from the effect of mental arithmetic at 2.5 and 12.5 Hz. Suppression of lower frequency alpha activity was more pronounced during calculation than during eye-opening. Compared with the eyes closed condition, eye-opening showed a highly significant suppression at 10 and 12.5 Hz (alpha activity) and from 15 to 25 Hz (beta activity). Mental arithmetic induced significant suppression at 7.5 and 10 Hz and from 15 to 30 Hz. Eye-opening enhanced lower frequency activity which calculation suppressed.
Variation was greater between first, second and third calculations in pooled power spectral densities than between corresponding eye-opening epochs. It is suggested that these differences in effects of eye-opening and mental arithmetic reflect differences in underlying cerebral activity, rather than that an underlying factor common to both effects may be orbital in origin.
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- Adrian, E. D., Matthews, B. H. C.: The Berger rhythm: potential changes from the occipital lobes in man. Brain 57, 355–385 (1934).Google Scholar
- Chapman, R. M., Armington, J. C., Bragdon, H. R.: A quantitative survey of kappa and alpha EEG activity. Electroenceph. clin. Neurophysiol. 14, 858–869 (1962).Google Scholar
- Cobb, W. A.: The normal adult EEG. In: Electroencephalography. A symposium on its various aspects (second ed.) (D. Hill and G. Parr eds), p. 232–249. London and New York: Macdonald and Co. 1963.Google Scholar
- Dewan, E. M.: Occipital alpha rhythm eye position and lens accomodation. Nature (Lond.) 214, 975–977 (1967).Google Scholar
- Ellis, N. W., Last, S. L.: Analysis of the normal electro-encephalogram. Lancet 1953 I, 112–114.Google Scholar
- Esser, R. A., Bickford, R. G.: Observations on simultaneous recordings of individual frequencies in the alpha band. Electroenceph. clin. Neurophysiol. 2, 231–232, (1950).Google Scholar
- Glass, A.: Blocking of the occipital alpha rhythm and problem-solving efficiency. Electroenceph. clin. Neurophysiol. 11, 605 (1959).Google Scholar
- —: Mental arithmetic and blocking of the occipital alpha rhythm. Electroenceph. clin. Neurophysiol. 16, 595–603 (1964).Google Scholar
- —: Comparison of the effect of hard and easy mental arithmetic upon blocking of the occipital alpha rhythm. Quart. J. exp. Psychol. 18, 142–152 (1966).Google Scholar
- —: Changes in the prevalence of alpha activity associated with the repetition, performance and magnitude of arithmetical calculations. Psychol. Forsch. 30, 250–272 (1967).Google Scholar
- Glass, A., Kwiatkowski, A. W.: Normal power spectral density changes in the EEG during mental arithmetic and eye-opening. Electroenceph. clin. Neurophysiol. 25, 507 (1968).Google Scholar
- Hess, E. H., Polt, J. M.: Pupil size in relation to mental activity during simple problem-solving. Science 143, 1190–1192 (1964).Google Scholar
- Jasper, H. H.: Report of the committee on methods of clinical examination in electroencephalography. Electroenceph. clin. Neurophysiol. 10, 370–375 (1958).Google Scholar
- Kreitman, N., Shaw, J. C.: Experimental enhancement of alpha activity. Electroenceph. clin. Neurophysiol. 18, 147–155 (1965).Google Scholar
- Lippold, O. J. C., Novotny, G. E. K.: Tremor of the extra-ocular muscles as the generator of the alpha rhythm: cooling the orbit in man. J. Physiol. (Lond.) 194, 28–29P (1968).Google Scholar
- Lorens, S. A., Darrow, C. W.: Eye movements, EEG, GSR and EKG during mental multiplication. Electroenceph. clin. Neurophysiol. 14, 739–746 (1962).Google Scholar
- Mimura, K., Sato, K., Ozaki, T., Honda, N., Masuya, S.: On the physiological significance of the EEG changes caused by sonic stimulation. Electroenceph. clin. Neurophysiol. 14, 683–696 (1962).Google Scholar
- Mulholland, T., Evans, C. R.: Oculomotor function and the alpha activation cycle. Nature (Lond.) 211, 1278–1279 (1966).Google Scholar
- Mundy-Castle, A. C.: The electroencephalogram and mental activity. Electroenceph. clin. Neurophysiol. 9, 643–655 (1957).Google Scholar
- Sato, K.: A new practical method for obtaining the number of the components in the electroencephalogram. Folia. psychiat. neurol. jap. 4, 309–313 (1955).Google Scholar
- —, Mimura, K.: The effect of photic stimuli on the constituent element of EEG. Jap. J. Physiol. 6, 206–217 (1956).Google Scholar
- - Ozaki, T., Mimura, K., Masuta, S., Honda, N.: On the frequency of EEG activity obtained by intermittent click stimulation. No 5 Proc. VIIIth Ann. Meet. Jap. EEG Soc. and XIIth Ann. Meet. Jap. EMG Soc. Hirosaki, 5–7 (1959).Google Scholar
- Schallek, W., Lewinson, T., Thomas, J.: Power spectrum analysis as a tool for statistical evaluation of drug effects on electrical activity of brain. Int. J. Neuropharmacol. 7, 35–46 (1968).Google Scholar
- Sokolov, E. N.: Higher nervous functions: the orientating reflex. Rev. Physiol. 25, 545–580 (1963).Google Scholar
- Suhara, K., Suzuki, H.: Some results of EEG analysis by analog type analyzers and finer examinations by a digital computer. Ann. Inst. Stat. Maths., Suppl. 3, 89–98 (1964).Google Scholar
- Volavka, J., Matoušek, M., Roubíček, J.: Mental arithmetic and eye-opening. An EEG frequency analysis and GSR study. Electroenceph. clin. Neurophysiol. 22, 174–176 (1967).Google Scholar
- Walter, D. O.: On units and dimensions for reporting spectral intensities. Electroenceph. clin. Neurophysiol. 24, 486–487 (1968).Google Scholar
- —, Rhodes, J. M., Brown, D., Adey. W. R.: Comprehensive spectral analysis of human EEG generators in posterior cerebral regions. Electroenceph. clin. Neurophysiol. 20, 224–237 (1966).Google Scholar
- Walter, W. G.: Normal rhythms — their development, distribution and significance. Evoked activity. In: Electroencephalography. A symposium on its various aspects (D. Hill and G. Parr eds.), p. 224–227. London and New York: Macdonald & Co. 1950.Google Scholar