Oscillatory Model of Short Term Memory

of the system. We regard this result as very signicant, in view of the fact that the same holds for the limited psychological ability of attention and STM. It may indicate that the oscillatory model contains the key to the understanding of these psychological ndings. In order to validate the hypothesis that STM is based on oscillatory correlations between ring rates of neurons, some more experimental neurobiological and psy-chophysical research is required. While no conclusive results were yet obtained from recordings of the cortical activity in the monkey, some positive support has been obtained in psychophysical experiments. Preliminary results show that an oscillatory component can be found in the percentage of correct responses in STM matching experiments (Usher & Sagi 1991). Our mathematical model is based on many specic assumptions. We believe that our main results are characteristic of a class of such models which can be obtained by changing various elements in our system. The main point is that dynamical storage of information can be achieved through staggered oscillations of memory activities. Moreover, to sustain them in the absence of an external input, a poten-tiation capability has to be present. A model which contains both should be able to accomodate STM in the fashion which we have demonstrated.