PERFORxMANCE AFTER IRRADIATION TO THE HEAD 713 



Radiation Schedule 



Subjects were placed in a 3X 3 X 3 ft cage of steel bars located in the 

 center of an octagonal room. Four sides of the octagon were permanent walls, 

 and four contained one-way vision windows. 



Each subject was observed simultaneously by four investigators during 5 

 days prior to irradiation and by two investigators during 5 days following 

 radiation, and selected subjects were observed clinically during subsequent 

 days. 



One observer made verbal recordings similar to those made by McDowell 

 et al. (1956). Another recorded preselected activities by punching keys of a 

 specially constructed console similar to that of Hammack (1960) . The third 

 and fourth observers recorded selected single aspects of behavior when they 

 occurred. 



The key-punched activities w-ere manipulatory (manipulation of the cage, 

 puzzle, and self) ; visually directed behavior (general visual survey, visual 

 regard of the cage, puzzle, and self, and visual regard to sounds) ; and 

 postural behavior (cage shaking, bouncing, pacing, shifts in location, resting, 

 and body orientation to uncontrolled noise from the laboratory and to con- 

 trolled hammering on the wall in a predetermined random rhythm) . 



The subjects engaged in approximately four activities each minute. They 

 spent most of the time surveying the sterile and unfamiliar environment, 

 picking at and inspecting the cage, and pacing. Table I compares our data 

 with data obtained by McDowell ct al. (1956), who observed pairs of 

 monkeys in their living cages. The most prominent category in their study 



TABLE I 



A Comparison of the Performance of Monkeys in 

 Two Studies Which Employed Systematic Observations 



Category 



Self involved 

 Rapid energy 

 expenditure 

 Visual sur\ey 

 Inanimate object 

 Other animal 



" Values in both studies are computed without including shifts in location. Inanimate object includes 

 looking at as well as manipulation of particular objects. 



