The effect of instructions on the judgement of brightness

A brightness constancy experiment using ten subjects showed that different instructions significantly affect the subject's PSE judgement. Variations in the reflectance of the standard target and in the background and illumination of the variable target did not influence the effect of different instructions. The use of the D-ratio as constancy index in this study confirms an earlier theoretical finding that other brightness constancy ratios introduce an artefact into experimental results.     

Nostalgia and the emotional tone and content of song lyrics

Emotion and topic were manipulated in original song lyrics. Participants completed Batcho's and Holbrook's nostalgia surveys and rated 6 sets of lyrics for happiness, sadness, anger, nostalgia, meaning, liking, and relevance. Nostalgic lyrics were characterized by bittersweet reverie, loss of the past, identity, and meaning. Contrary to theories linking nostalgia to pathology, participants who scored high on Batcho's measure of personal nostalgia preferred happy lyrics, found them more meaningful, and related more closely to them. Consistent with theories relating nostalgia to social connectedness, high-nostalgia respondents preferred other-directed to solitary themes. Historical nostalgia was associated with relating more closely to sad lyrics.     

The establishment of stimulus control by instructions and by differential reinforcement

A repeated acquisition design was used to study the effects of instructions and differential reinforcement on the performance of complex chains by undergraduates. The chains required responding on a series of keys that corresponded to characters that appeared on a monitor. Each day, subjects performed a new chain in a learning session and later relearned the same chain in a test session. Experiment 1 replicated previous research by showing that instructional stimuli paired with the correct responses in the learning sessions, combined with differential reinforcement in both learning and test sessions, resulted in stimulus control by the characters in each link. Experiment 2 separated the effects of instructional stimuli and differential reinforcement, and showed that stimulus control by the characters could be established solely by differential reinforcement during the test sessions. Experiment 3 showed that when a rule specified the relation between learning and test sessions, some subjects performed accurately in the test sessions without exposure to any differential consequences. This rule apparently altered the stimulus control properties of the characters much as did differential reinforcement during testing. However, compared to differential reinforcement, the rule established stimulus control more quickly.     

The effect of instructions on performance in the Wason selection task

The effect of instructions on performance on the standard abstract form of Wason’s selection task was examined. Instructions to determine whether or not the statement is violated did not lead to an increase in correct responding, contrary to previous suggestions that such instructions would induce falsification strategies, but rather to an increase in verification bias. Instructions to determine whether the statement is true or false led to increased variability in performance, supporting the suggestion that such instructions are inherently ambiguous. Thus, the results demonstrate that the form of instructions can have a significant effect on performance in the selection task. Verification bias did better as an explanation of the data than did matching bias, which only fared well when its predictions coincided with those of verification bias. A substantial proportion of the data was unaccounted for by either of these strategies, which is consistent with the findings of a number of other recent studies.