ALPHA-RHYTHM PARAMETERS AND SHORT-TERM-MEMORY SPAN

The study examined a statement from the neurophysiological model of A. N. Lebedev as to whether short-term memory span is related to a ratio of the alpha-rhythm frequency and parameters of step-type behaviour of wave processes in the EEG alpha range. Forty young healthy subjects p erformed a digit memory test. EEG signals were recorded from the occip ital area during a resting period with eyes closed. As one of the para meters of step-type behaviour of alpha oscillations a mean value of th e difference between periods of neighbouring peaks in the alpha spectr a was calculated. A second parameter - the duration of alpha spindles, considered to be a superposition of alpha oscillations - was also mea sured. It was shown that the ratio of the alpha-rhythm frequency to pa rameters of the step-type behaviour of alpha oscillations positively c orrelated with memory performance. (C) 1997 Elsevier Science B.V.