PERIODICITY IN HUMAN BEINGS AND MICE 



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Time of day 



Fig. 27. Unequal distribution of epileptic seizures during the hours of 

 the day, on two schedules, maintained for many years. Same subject, 

 "day-type." Note change in seizure distribution following change in 

 routine. Daily routine may be regarded as the environmental synchronizer 

 of seizure rhythm; the clock hour as such does not matter in determining 

 times of occurrence of seizures. 



respiratory rate. We have earlier referred to other aspects of her 

 work that dealt with the successful shift of phase of rhythm by a shift 

 in routine. In commenting on our problem as a whole, Bykow points 

 out that in the monkey "... a 'change' of 24-hour periodicity in 



