Information Storage in Nerve Cells 



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Fig. 5. Conditioning of a rhythmic burst response to a single flash. Anodal 

 polarization was applied to the visual receiving area. Single flash elicited a 

 single burst in a quiescent (A) and in a randomly firing cell (B). Three per 

 second stroboscopic stimulation (C) produced driving of unit discharge at tliat 

 frequency. A single flash (D) delivered thirty seconds after termination of the 

 rhythmic stimulus resulted in repetitive unit discharge at about three per second. 

 Unit potentials are seen in the upper channel of tlie oscilloscope; stimulus artifacts 

 in the lower channel. Amplitude calibration: 2 millivolts. Time calibration: 

 500 milliseconds (A & B) and one second (C & D) (40). 



per second tone (Fig. 4D) invariably failed to induce a change in 

 the pattern of unit firing. About forty minutes after cessation of 

 polarization neither signal was effective (Figs. 4E and F). Under 

 these circumstances it seemed evident that the polarized cell 

 population had retained some stipulation of signal characteristics 

 so that for a brief period in the post-polarization interval the cells 

 behaved differentially with respect to the two signals. 



Short-term storage of a temporal pattern has also been observed 

 in cells of the visual cortex. Figure 5A illustrates the response of 

 a quiescent cell to a brief flash of light, (the flash artifact is recorded 

 on the second beam of the oscilloscope). Figure 5B shows a similar 

 burst response in a spontaneously active cell. During anodal 

 polarization it was extraordinarily easy to "drive" such cells with 



