FIG. I I . Records taken with the toposcope in the laboratory 

 of Dr. Sem-Jacobsen in Oslo from a psychopathic patient in 

 whom electrodes had been implanted intracerebrally three 

 days earlier. A. The approximate position of the electrodes for 

 the 22 indicator tubes, derived from X-ray projection drawings. 

 The anterior channels were connected to electrodes deep in 

 the medial structures, the posterior ones were in the middle of 

 the parietal and occipital lobes. B. The distribution of the 

 intrinsic alpha rhythms with the eyes shut. There are three 

 distinct components, one at 8.8 cycles per sec. in channel 14, 

 another at 8.5 cycles per sec. in channels 16 and 18 through 

 22, and a third at 915 cycles per sec. in channel 17. There is 

 also a theta rhythm at 7 cycles per sec. in channel 5. The alpha 

 rhythms in the posterior regions show the characteristic phase 

 differences suggesting a moving source. The signals in channel 

 8 are artefacts arising at a high-resistance electrode. C. Record 

 made a few seconds later during flicker stimulation at 8.8 

 Hickers per sec. The only regions showing clear fundamental 

 synchronization arc those corresponding to channels i i and 1 7 

 and 19. Channel 14 shows deceleration to 8.6 cycles per sec, 

 channel 20 is unaffected and channels 21 and 22 show a re- 

 sponse at twice the stimulus rate. D. Flicker .stimulation with 

 triplet groups of flashes at 4.2 groups per sec. evokes a replica of 

 the stimulus pattern only in channels 18 and 20. Channels 14, 



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