A model was proposed as an alternative to current models for categorical perception, which refers to the apparent responding to stimuli only in absolute terms. The model proposed that a single (common) factor causes both a peak in the discrimination function and a categorical dichotomy and thus the correlation between the two. (Editor/RK)

Two experiments examined factors underlying false alarms on recognition tests when the elements of the test items were presented alone for study at different points in time, and when the elements were parts of different 2-element units during study. (Editor)

Three experiments studied the effect of amount and type of concurrent memory load on the rate of readout from iconic memory. (Editor)

When asked to report the first digit that comes to mind, a predominant number (28.4 percent) of the respondents choose 7. Three further experiments sought to establish whether this predominance is due to an automatic activation process or to a deliberate choice. (Editor)

Previous research has investigated the effects of interpresentation lag within the context of experimenter-controlled lag values. The present study attempted to explore subject-controlled lag effects on paired-associate learning. (Editor)

Research by Posner and Mitchell (1967) was used to investigate levels of noise processing in testing subjects' ability to "gate out" the processing of irrelevant and unwanted material. Three experiments are reported in which subjects had to judge whether two letters were the "same" or "different". Noise elements were included to test attention…

The negative-contrast effect occurs when animals that are shifted from large to small reward temporarily drop below small reward control groups. The basic question asked here in three experiments was whether animals tested under a specific drive level will behave as though they expect a reward magnitude previously received, depending on the reward…

Assesses the validity of physiological versus learning interpretations of illness-preexposure effects. (Author/RK)

Concerns the examination of conditioned stimulus--unconditioned stimulus (CS--UCS) intervals of different lengths. Demonstrates the feasibility of using a forewarned reaction time procedure with an innocuous imperative stimulus for the investigation of classical conditioning. (Editor/RK)

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)

Investigates how the inhibition and latency-reduction effects interact with each other and how they change with changes in the intensity of the startle-eliciting stimulus. (Author/RK)

Three experiments investigated the relationship in speech perception between the mechanisms that determine the source of speech sounds and those that analyze their actual acoustic contents and extract from them the acoustic cues to a sound's phonetic description. (Author/RK)

Experimenters in the past have reported that when insulin is used as the unconditioned stimulus (US), rats will learn an aversion to a sodium chloride but not a sucrose solution, whereas with formalin as the US, they will learn an aversion to a sucrose but not a saline solution. The present experiments failed to confirm these findings. (Editor)

These experiments investigate the degree to which neophobia, the reluctance to consume novel food, can be modified by toxicosis, the conditions under which the contingency between ingestion and illness enhances neophobia, and the manner in which previously learned aversions mediate subsequent enhanced neophobia. (Author/RK)

These experiments investigate situations in which a negative correlation involves a 24 hour delay between the occurrence of a conditioned stimulus and an unconditioned stimulus; they also investigate the mechanism by which any inhibition so produced might occur. (Author/RK)