|
| Reinforcement Effects |
| Saturday, May 29, 2004 |
| 2:30 PM–3:20 PM |
| Beacon D |
| Area: EAB |
| Chair: Raul Avila (National University of Mexico) |
| |
| Relative Effects of Reinforcement: Why does Upcoming Food-Pellet Reinforcement Increase Responding for Sucrose? |
| Domain: Applied Research |
| JEFFREY N. WEATHERLY (University of North Dakota), Jeri Nurnberger (University of North Dakota) |
| |
| Abstract: Myriad studies have documented that the conditions of reinforcement in one portion of an experimental session can alter response rates in another portion. Although much of the research has focused on contrast effects, our research has focused on positive induction. Specifically, we have reliably demonstrated that rats will increase their rate of operant responding for sucrose reinforcement if food-pellet, rather than the same sucrose, reinforcement is upcoming within the session. There are numerous potential explanations for why this increase in response rates occurs. The present study will present results from three separate experiments that have investigated its cause. The first asked whether rats would learn a new task more quickly when displaying induction than when not displaying induction. The second asked whether induction would be present when rats responded on concurrent schedules of reinforcement and whether choice responding would also be altered. The third asked whether induction was also accompanied by a change in the consumption of the sucrose reinforcers. These three experiments are related because the results of all three are consistent with the idea that induction occurs because the value of the sucrose reinforcers has been increased. |
| |
| Effects of Schedule-induced-drinking Conditions on Operant Licking for Water |
| Domain: Applied Research |
| RAUL AVILA (National University of Mexico), Jorge A. Ruiz (National University of Mexico), Carlos A. Bruner (National University of Mexico) |
| |
| Abstract: Food-deprivation, spaced-food deliveries and continuous access to water are necessary conditions for schedule-induced drinking by rats. The contribution of each of these conditions to the typical inverted U distribution of licking during the food interval was studied. The procedure consisted in adding sequentially each of these conditions to the scalloped pattern of licking for water by thirsty rats controlled by a 64 s fixed-interval (FI) schedule of water reinforcement. In the second condition of the study, adding food-deprivation lowered the FI-scallop. In the third condition, food was introduced within the water FI resulting in a double licking scallop, one before food and the second before water. In the fourth condition, the FI schedule was shortened from 64 to 2-s . This operation removed the pre-food acceleration in rate but left intact the discriminative function of the food intrusion. In the fifth condition, water deprivation was removed, thus turning operant into induced licking. These results clarify the contribution of each condition of schedule-induced drinking to the typical inverted U distribution and suggested that instead of being peculiar to the phenomenon can be interpreted as the effect of manipulations previously described in both, the motivation and operant conditioning literatures. |
| |
|
| |