Abstract
Twelve devices of about the same type as HESSS, (6), consisting of two parts and a container, as shown in Fig. 1 were used, one device for each rat.
After some adaptation procedures for 11 days, each of 12 white rats, weighing 231 to 330g and about 4 months old at the beginning of the experiment, was allowed to hoard through the alley to its home cage Oriental Lab MF pellets (2g. a piece) laid in the container for 30 minutes under 22. 5-hour food deprivation condition every day for successive 16 days.
On the day when each rat's hoarding behavior reached comparative stability after the first 7 days of the 16 days, one of two tranquilizers, chlorpromazine and chlordiazepoxide, was injected two hours before the beginning of 30-minute hoarding trials for that day. The other drug was injected in the same way on the third day after the previous injection. Except the additional injection, the procedures on the injection day were quite the same as those on the day of non-injection. The schedules are shown in Table 1.
The numbers of carrying pellets, the amount of carried pellets and hoarded pellets, and other factors such as temperature, food intake were measured.
As others were of about the same trend and other influencing factors on the hoarding than drugs used were statistically insignificant, only the main results were shown in Fig. 2. and Table 2.
The two tranquilizing drugs surprisingly inhibited the hoarding behavior, which, considering the nature of the drugs, led the writer to this conclusion : that there is not an only special exclusive condition which accompanies hoarding behavior directly as referred to in many conventional studies on hoarding, but hoarding behavior appears as a result of more general and indirect processes with several steps of state elements mediated between the input of any of many special conditions and the output of hoarding behavior. The mediating processes can be activated by any of many special conditions, become more general step by step, and induce integrated hoarding behavior.
