Information that is spaced over time is better remembered than the same amount of information massed together. This phenomenon, known as the spacing effect, was explored with respect to its effect on learning and neurogenesis in the adult dentate gyrus of the hippocampal formation. Because the cells are generated over time and because learning…

One conditioned taste aversion experiment with rats assessed the impact of extinguishing a target conditioned stimulus (CS), S, in compound with a second CS, A, upon conditioned responding elicited by CS S when presented alone at test. Following initial conditioning treatment with CSs A and S, the experiment manipulated number of extinction trials…

This study is concerned with the transfer of learned helplessness from one aversive motivator, shock, to another, frustration. (Author)

If animals receive inescapable electric shocks, their subsequent avoidance-escape learning is poor. This phenomenon, which can be called "the interference effect", was studied in four experiments. (Editor)

Comments on Maier and Seligman's research (EJ 138 911) on learned helplessness, specifically on their analysis of alternatives to the learned helplessness hypothesis. (Author/RK)

In autoshaping experiments, we quantified the acquisition of anticipatory head poking in individual mice, using an algorithm that finds changes in the slope of a cumulative record. In most mice, upward changes in the amount of anticipatory poking per trial were abrupt, and tended to occur at session boundaries, suggesting that the session is as…

The following experiments are an attempt to clarify the role of learned safety by investigating the applicability of the concept of conditioned inhibition to a taste-aversion procedure and by differentiating its effects fromthose of latent inhibition. (Author)

The learning of backward associations by pigeons during training of forward associations was studied in three experiments using a symbolic matching task. The data are contrasted with the strong evidence of learning of backward associations by humans. (Editor/RK)

Stimulus analyzer theory as proposed by Sutherland and Mackintosh (1971) makes the unique prediction that the first-experienced reinforcement schedule will influence resistance to extinction more than subsequent schedules. Results presently reported of runaway acquisition and extinction indicate the opposite: C-P consistently produce substantially…

These experiments attempt to optimize the possibility of demonstrating blocking in a taste-aversion paradigm and to elucidate the conditions under which this interference occurs. (Author/RK)

To complement investigations of the direct effects of lithium toxicosis on consummatory behavior, these experiments were designed to determine the aftereffects on drinking of exposure to a conditioned stimulus previously paired with lithium. (Author/RK)

In four different experiments, brief illumination of a localized visual stimulus was followed by grain presentation unless the pigeon approached the light. Results indicate that although response-reinforcer relations do play a role, stimulus-reinforcer contingencies are the dominant factor in establishing and maintaining approaches to the…

An analysis of two paradigms suggests that predictions in regard to the effects of stimulus preexposure must take into account not only the novelty of the stimulus, but the relationship of that novelty to that of the environment at the time of testing. (Editor/RK)

Analyzes the temporal features of the transient unconditioned stimulus preexposure effect observed by Cannon (EJ 123 672) and attempts to determine whether a preconditioned stimulus toxin presentation can both condition a backward taste aversion and interfere with the development of a forward aversion. (Author/RK)