Two lick suppression studies were conducted with water-deprived rats to investigate the influence of spatial similarity in cue interaction. Experiment 1 assessed the influence of similarity of the spatial origin of competing cues in a blocking procedure. Greater blocking was observed in the condition in which the auditory blocking cue and the…

In two experiments, the evidence showed that 20 min of forced swimming by rats caused aversion to a taste solution consumed before swimming. When one of two taste solutions (sodium saccharin or sodium chloride, counterbalanced across rats) was paired with swimming and the other was not, the rats' intakes of these two solutions showed less…

Pigeons were trained in a matching task with either color (group color-first) or line (group line-first) samples. After asymmetrical training in which each group was initially trained with the same sample on all trials, marked retention asymmetries were obtained. In both groups, accuracy dropped precipitously on trials involving the initially…

Previous failures to condition preferences for the unacceptable taste cues sucrose octaacetate (SOA) and citric acid (CA) using a reverse-order, differential conditioning procedure (Forestell & LoLordo, 2000) may have been the result of low consumption of the taste cues in training or of their relatively low acceptability to rats that are thirsty…

In Experiment 1, we trained four pigeons to concurrently discriminate displays of 16 same icons (16S) from displays of 16 different icons (16D) as well as between displays of same icons (16S) from displays that contained 15 same icons and one different icon (15S:1D). The birds rapidly learned to discriminate 16S vs. 16D displays, but they failed…

Using a context discrimination procedure and rats as the subjects, the formation of context-dependent aversions to novel and familiar fluids was investigated. Experiment 1 revealed that context dependency could be established to a novel fluid (saccharin) after three cycles of context discrimination training and that the acquired context dependency…

Research has demonstrated that rats' rates of operant behavior maintained by 1% sucrose reinforcement in the first half of an experimental session are heightened when food-pellet reinforcers, rather than 1% sucrose, will be available in the second half. Experiment 1 showed that rats that had been displaying this positive induction effect acquired…

In conditioned suppression of water licking behavior by rats, we obtained data indicating general transfer of fear conditioning. A series of experiments resulted in two major findings. First, pairing of a neutral stimulus with a shock in the initial conditioning task facilitated acquisition of subsequent fear conditioning to another neutral…

In Experiment 1, pigeons were trained at a 0-s baseline delay to discriminate sequences of light flashes (illumination of the feeder) that varied in number but not time (2f/4s and 8f/4s). During training, the intertrial interval was illuminated by the houselight for Group Light, but it was dark for Group Dark. Testing conducted with dark delay…

Two appetitive conditioning experiments with rats examined reacquisition after conditioned responding was eliminated by either extinction or by a partial reinforcement procedure in which reinforced trials were occasionally presented among many nonreinforced trials. In Experiment 1, reacquisition to a conditional stimulus (CS) that had been…

McSweeney and Weatherly (1998) argued that differential habituation to the reinforcer contributes to the behavioral interactions observed during multiple schedules. The present experiment confirmed that introducing dishabituators into one component of a multiple schedule increases response rate in the other, constant, component. During baseline,…

Environmental familiarization is a learning phenomenon embedded within most tasks used to study learning and motivation. Given its prevalence there is surprisingly little systematic behavioral research on factors affecting familiarization. The six experiments reported in the present report used rats' tendency to interact more with a novel object…

Rats cached pieces of cheese on four different arms of an eight-arm radial maze. On a retrieval test given 45min later, rats learned to return to arms where food was cached before arms where food had not been cached. Tests were then performed in which cache sites on one side of the maze were always modified (pilfered or degraded), but cache sites…

In earlier studies with rats, the effectiveness of the auditory element of a tone--light discriminative stimulus was enhanced when the conditioned incentive value of the compound was negative rather than positive. The present experiment systematically replicated these results in pigeons trained to press a treadle in the presence of a tone--light…