Constraints on Pavlovian conditioning of the pigeon: Relative conditioned reinforcing effects of red-light and tone CSs paired with food

Recent Pavlovian conditioning experiments presented all possible CS-US combinations of red-light and tone CSs and food and shock USs to separate groups of pigeons. Pigeons receiving shock USs demonstrated conditioned head raising followed by prancing to both CSs, but CRs were acquired more rapidly to tone than to red light. Although pigeons receiving food USs rapidly acquired a conditioned response of pecking to the red-light CS, there was no evidence of conditioned responding in groups receiving tone-food pairings. This outcome left open the possibility that Pavlovian pairings of tone and food may have resulted in association formation that was not revealed in performance. The present series of experiments attempted to reveal that association, using an indirect method of assessment, conditioned reinforcement. Experiment 1 demonstrated that both red light and tone paired with food became positive conditioned reinforcers, suggesting that an association between tone and food was formed in the same number of Pavlovian conditioning trials that previously failed to yield any direct evidence of conditioning. Experiment 2, which presented fewer conditioning trials, revealed that the tone-food association was formed less rapidly than the red light-food association. Experiment 3 demonstrated that the observed outcomes were not attributable to unconditioned, rather than conditioned, reinforcing effects of the Css.     

Word age-of-acquisition and lexical decision making

This paper reports two experiments concerning the effects of word age-of-acquisition and other word attributes on speed of lexical decision. Analyses of group average data indicated that word length, frequency and familiarity were the major determinants of decision speed. Previous reports of age-of-acquisition effects on lexical decision are attributed to failures to control for word familiarity.     

The effects of a salient self-schema on the evaluation of proattitudinal editorials: Top-down versus bottom-up message processing

The effects of a salient self-schema on message evaluation were studied. Subjects were identified who characterized themselves using trait adjectives that reflected the prototype of either a “religious” or a “legalistic” person. Equally persuasive sets of proattitudinal messages were developed empirically using weak arguments. Half of the messages were developed to reflect a “religious” perspective on the issue (capital punishment, abortion) whereas half were developed to reflect a “legalistic” perspective on the issue. Religious and legalistic subjects were then exposed to religious or legalistic arguments supporting an equally acceptable position (e.g., eliminating capital punishment). Afterward, subjects evaluated the persuasiveness of the communication and listed their thoughts as part of a “curriculum development project.” Results suggested that subjects when exposed to a schema-relevant message arguments for a position in which they believed were more positive about the quality of the message arguments and in their cognitive responding. These data extend the heuristic value of selfschemata to the area of attitudes and suggest that cognitive responses in persuasion are subjectively rather than objectively rational.     

Understanding and appreciating metaphors

We consider three theories that have dominated discussions of metaphor. One view is that metaphors make comparisons, the basis for the comparison being the features (or categories) that the terms of the metaphor share. The second view is that metaphors involve an anomaly. The third view is that metaphors are ‘interactive’, producing a new way of seeing the terms. We propose a new theory—the domains-interaction view—that draws on elements of all three earlier views, but borrows especially from the interaction view. We consider the implications of our theory for three questions: What are metaphors? How are they understood? What makes a good metaphor? We argue that metaphors correlate two systems of concepts from different domains. The best metaphors involve two diverse domains (more distance between domains making for better metaphors) and close correspondence between the terms within those domains. We call the degree of correspondence within-domain similarity. Metaphors are interpreted in several stages: the terms of the metaphor are encoded; the domains involved are inferred; the structures to be seen as parallel are found; the correspondences between these structures are ‘mapped’ or constructed; the terms of the metaphor are compared. If the terms are not seen to match or occupy analogous roles in their different domains, then the metaphor may be reinterpreted. The evidence on all this is tentative but supports our view. We review two studies (Tourangeau and Sternberg, 1981) that support the hypothesis that distance within domain relates negatively to aptness, whereas distance between domains relates positively. Several studies on comprehension tend to disconfirm the comparison theory's notion that the tenor and vehicle necessarily share features. Tenor and vehicle also appear to have asymmetrical roles in the interpretive process.     

Blowing in the wind: Perceiving structure in trees and bushes

When lights are mounted at the ends of the limbs of a tree and the surround darkened such that branches and trunk are not visible, viewers can nonetheless make systematic and precise judgments about the unseen structure of the tree through its motion. They seem to perform this task by picking up information about the relative arborization of the tree through the vector paths of the lights on the limbs. Theoretically speaking, the focus of this study is on the perception of second-order centers of moment; previous studies have focused on the perception of first-order centers. A second-order center in a tree-like structure is the location where limb meets trunk, and it is these that perceivers can infer from the dynamic display. The importance of this study is to demonstrate further that the study of centers of moment makes possible a detailed and differential study of event perception.     

The development of alertness

Two experiments explored variation in the alerting process across age and warning interval as well as the effects of alertness on subsequent processing. Experiment 1 obtained alertness functions for a group of 5-year-olds, 8-year-olds, and adults. Results revealed strong age differences in speed of alerting and in maintenance of alertness over a 1-sec interval. Five-year-olds alerted more slowly than older groups and sustained optimal alertness less well. Both groups of children showed more variability in alerting functions compared with adults. Experiment 2 examined the degree to which age differences in processing speed were attributable to differential speed and maintenance of alerting. Masking functions obtained across variations in the alerting interval revealed that when level of alertness was optimal in both 5-year-olds and adults, minimal age differences in processing speed were observed. During short, nonoptimal alerting intervals, speed of processing in adults was faster than in 5-year-old children. The pattern of results across studies suggested that alertness can fluctuate over time in young children, that level of alertness affects subsequent perceptual processing speed, and that developmental variation in speed and maintenance of alertness can partly explain observed age differences in processing speed. The potential role of alertness in more complex cognitive tasks is discussed.     

The development of spatial understanding in infancy

This paper examines the development of spatial understanding between 8 and 24 months. In particular, it examines whether young infants code changes in the position of an object or themselves in geographic or egocentric terms. The infants sat in a baby chair which was attached to a circular table in such a way that either the infant could be rotated around the edge of the table or the table-top itself could be rotated. Rotation of infant or table could be performed independently or simultaneously. Infants were shown an object which was then hidden under one of either two or three identical cups sitting on the table. Before the infant was allowed to search for the toy, either the table, the infant, or both were rotated, a procedure which resulted in an invisible displacement of the object in terms of geographical and/or egocentric spatial position. Rotations of 60, 90, 120, and 180° were used. Three groups of infants were tested, one cross-sectional (12–24 months), one longitudinal (12–24 months), and one consisting of a group of infants already known to be accelerated in object concept development (8–20 months). The cross-sectional results indicated that egocentric responding continues well into the second half of the second year of life. Even with fortnightly exposure to the tasks, egocentric responding was still evident in some longitudinal babies as late as 19 months. The results of the accelerated group suggest that acceleration through the sequence of object concept development facilitates development of spatial understanding in a wider sense, that is, in the sense of understanding the interrelation of positions in space. The implications of these results for competing theories of the source of object concept errors are discussed.     

Reading and listening comprehension in Broca's aphasia: Lexical versus syntactical errors

Ten agrammatic Broca's aphasics were presented with a series of four picture plates together with a spoken or written sentence stimulus. All sentence stimuli were of the structure, the + N + is/are + V + ing + the + N. The four pictures on each stimulus plate represented (a) the correct response, (b) a reversal of the stimulus sentence subject and object, (c) a change in the number of the subject of the stimulus sentence, and (d) a change in one of the major lexical items of the stimulus sentence. Subjects selected the correct picture most often. When they erred, they usually selected a subject-object reversal. Number errors were less frequent, and the patients seldom selected a change in major lexical item. This pattern occurred with both written and spoken sentences. These results were interpreted as reflecting the dependence of agrammatic Broca's aphasics on the semantic interpretation of the lexicon for decoding sentences in the face of deficits in syntactical-grammatical interpretation, irrespective of comprehension modality.