Spontaneous alternation of two closely-placed goals in the white rat

EFFECT OF INTERTRIAL INTERVAL AND REMOVAL OF THE SUPRAPHARYNGEAL GANGLION UPON SPONTANEOUS ALTERNATION IN THE EARTHWORM, <I>PHERETIMA COMMUNISSIMA</I>

“…Similar results were found with cochroaches (Iwahara, 1956;Iwahara & Soeda, 1957) and with isopods (Iwahara, 1963;Iwahara & Suzuki, 1964). However, the significant subject variance was observed in alternation when rats were used as Ss (Iwahara, 1957; same result was obtained with human Ss from the analysis of our previous studies in human alternation (Iwahara, 1959). Similarly individual differences were found to be significant in time measures in our alternation studies with rats (Fujita, 1955;Iwahara, Washiyama & Matsubara, 1959).…”

“…However, the significant subject variance was observed in alternation when rats were used as Ss (Iwahara, 1957; same result was obtained with human Ss from the analysis of our previous studies in human alternation (Iwahara, 1959). Similarly individual differences were found to be significant in time measures in our alternation studies with rats (Fujita, 1955;Iwahara, Washiyama & Matsubara, 1959). It is interesting to notice that the effect of intertrial interval upon alternation was not found and at the same time there were no significant individual variations in alternation in lower organisms, while both effects appeared in higher organisms.…”