lERZY KONORSKI 



117 



through several different ways). When the animal is restrained in the cage 

 or attached on the starting platform, a signal heralding that the food is 

 presented in a particular place is given; in many experiments such a 

 signal is provided simply by baiting one of the bowls in front of the 

 animal. Then after a number of seconds or minutes the animal is released 

 and if he remembers which signal was given, he will go to the correspond- 

 ing place and be reinforced there. 



After the first paper by Hunter appeared, a number oi authors studied 

 the delayed responses in various species, attempting to tnid the maximal 

 delay periods which can be achieved, the cues which are used by the 



Fic. I 

 Experimental setting used in our study. 

 Fi- ^2. F3' ''•"ff- iniddle, and right food tray. The bowls are auto- 

 matically moved into position by the experimenter using an electro- 

 magnetic device. E, table and seat for experimenter. S, starting 

 platform. Bj, B.,, B3, buzzers, Lj, L,, L3, lamps situated on the respective 

 food trays. (After Konorski, J. and Lawicka, W., 1959. Acu\ B'\o\og\ae 

 E.xperiiiieiiriilis, 19, 175-198). 



animals to solve the task, and the way in which the delay period is 

 'bridged' by the animal (Walton, 1915; Yarborough, 1917; Cowan, 

 1923; Yerkes and Yerkcs, 1928; Tinklepaugh, 1928; McAllister, 1932). 

 This form of experimentation grew in importance in the 'thirties of this 

 century when Jacobsen (1936) showed that delayed responses are dramati- 

 cally impaired or abolished by prefrontal lesions in monkeys and apes. 

 The results of these studies will be discussed in a later section. 



The delayed responses have been recently studied in our laboratory by 

 Lawicka and Konorski (Lawicka, 1957, 1959; Konorski and Lawicka, 

 1959; Lawicka and Konorski, 1959) in dogs and cats by using the experi- 

 mental setting presented in Fig. i . The animal was on the leash or in the 

 cage on the starting platform and a signal, visual or auditory, which we 



