Choice reaction time with a random foreperiod

Choice reaction latencies were measured at three different a priori probabilities for two stimulus alternatives. Unlike the results of some other studies, the mean latency of a given response was nearly the same whether the response was correct or incorrect. The discriminable stimuli were a 1000- or a 1700-Hz tone presented at 70 dB SPL. Latencies and standard deviations, based on about 17,000 observations, are reported for three observers. The data are compared with predictions of the optimum sequential model of Wald and Stone and two modifications of that random-walk model, one proposed by Link and Heath and the other proposed by Laming. Fast-guess analyses were also carried out. The three-parameter version of either the sequential or the modified random-walk models provided reasonably accurate predictions of the mean data for each observer. The parameters estimated by the fast-guess analysis were unrealistic. There are three obvious differences between this experiment and most previous choice reaction-time experiments. First is stimulus modality#x2014;we used an auditory signal, whereas most of the previous studies used a visual signal. Second, the observers practiced more in this experiment than in most previous experiments. Finally, there was a random foreperiod with a heavy penalty for anticipations. One or more of these factors is the probable reason for the discrepancy between our results and those of previous studies.     

Pronoun disambiguation: Accessing potential antecedents

Two general classes of pronoun disambiguation processes are considered. In reading “Jack threw a snowball at Phil, but he missed,” both possible antecedents of “he” (“Jack” and “Phil”) may be accessed initially. Or, the actual antecedent alone may be accessed after sufficient semantic context is encoded. To evaluate these alternatives, a yes-no-probe recognition task was used to measure priming of the potential antecedents in sentence comprehension. Subjects read sentences similar to the example and were presented a test word immediately following each sentence. Response times for the actual antecedent (“Jack”) and nonantecedent (“Phil”) probes were obtained. Results indicated that the nonantecedent as well as the antecedent was activated (accessed) in pronoun disambiguation. This conclusion was not affected by the ordering of the antecedent and nonantecedent in the first clause.     

Dimensions of metaphor

Two rating studies examined several dimensions of metaphorical sentences. A pool of 260 metaphors was constructed, all in the form “(noun phrase) is/are (noun phrase).” In Study 1 all of the items, and in Study 2, 98 of the items were evaluated on ten scales presumed to be important to the comprehension or interpretation of metaphors: semantic relatedness of the subject and predicate, comprehensibility, imageability, imageability of the subject (topic), imageability of the predicate (vehicle), degree of metaphoricity, metaphor goodness, ease of interpretation, number of alternative interpretations, and felt familiarity of the metaphoric ground. Both experiments revealed the rated dimensions to be highly interrelated, but some analyses allowed evaluation of alternative predictions based on current theoretical approaches to metaphor quality and interpretation. The results indicated consistent but mixed support for the general poisitions under consideration as each appeared to have strong and weak areas of applicability. The interrelationships among the scales are discussed, together with implications of the findings for current theories and future metaphor research.     

Mouse killing in rats induced by lesions of the medial hypothalamus or medial accumbens: short-term preoperative exposure to a mouse does not suppress the killing

Rats were either exposed or not exposed to a mouse in their living cage for a 48-hr period. At the end of this time a bilateral lesion was made in the medial accumbens region or in the medial hypothalamus. When tested 2 days postoperatively, the killing frequency among rats that had been exposed to mice preoperatively was not significantly lower than that of rats that were not preoperatively exposed. The ineffectiveness of preoperative experience in suppressing the mouse killing induced by medial accumbens and medial hypothalamic lesions is similar to that found previously with dorsal-median raphe lesions and olfactory bulb lesions and is in contrast to the ease with which preoperative experience prevents mouse killing induced by septal lesions and serotonergic lesions induced by 5,7-dihydroxytryptamine.     

Regret and disappointment in taxpayer reporting decisions: An experimental study

This paper reports on experiments which test whether factors such as regret or disappointment influence taxpayer compliance decisions. Previous tests of regret and disappointment theory have been based upon the common-ratio effect in which probabilities vary while outcomes are held fixed. In contrast, our experiments involved trials in which the outcomes were allowed to vary. Previous tests had mainly found evidence of regret effects and to a lesser extent were supportive of disappointment. In contrast, we were able to reject simple theories of both regret and disappointment. A second experiment produced evidence which indicates that whether or not rejected risky alternatives are resolved has no significant influence on subjects' choices. One would expect that regret could only occur when a subject learns the outcome of a non-chosen option. Hence this result can be seen as evidence against regret theory. We shall argue that there is a possible interpretation of regret theory which is compatible with this result.     

Influence of a televised model's vocalization pattern on infants

To assess the influence of a televised model's vocalizations on the vocal patterns of infant viewers, 32 infants at 6 months of age were presented either a televised adult model repeating a novel phoneme pattern (/ba/ba/ba/ba) or a control televised presentation of adult conversation selected from typical daytime programming. Sequential analyses of infant vocalizations revealed that infants exposed to the televised model altered their vocalization pattern, as indicated by a significant increase over base line levels in their production of a patterned series of discrete vocalizations. Infants exposed to the televised conversation showned no increase in this pattern of vocalization, and none of the infants in the study produced the novel phoneme (/ba/). The results indicate that televised presentation of discrete, repeated vocalizations can have an influence on the vocalization pattern of infants. The potential role of television in infant development is discussed.