Persistence of acquired behavioral control in the context of imprinting

Newly hatched Khaki Campbell ducklings (Anas platyrhynchos domesticus) were exposed to a moving object that immediately suppressed distress vocalizations occurring in a novel environment. The static visual and auditory features of this object acquired the ability to suppress distress vocalizations after eight 20-min sessions of exposure to the object in motion. The acquired suppressive properties of these features were found to persist throughout thirty 20-min sessions given over 10 days. During these sessions, the ducklings were continually exposed to the static features in the absence of visual movement. In a second experiment, the ability of these features in the absence of visual movement. In a second experiment, the ability of these features to serve as reinforcement for a pecking response was shown to persist for up to 56 hr. In one duckling, presentations of the static visual features did not maintain pecking behavior. However, it was shown that pecking responses could be re-instated in this duckling by introducing novel stimuli to the environment.     

Semantic memory for metaphor: The conceptual base hypothesis

The idea that people can encode and use an extremely abstract and general form of a complex linguistic (proverb) input-a conceptual base-was examined in two experiments. In Experiment I, each proverb was accompanied by either a conceptually related (good, mediocre, or poor) or an unrelated interpretation. The related interpretations were more effective recall prompts than were the unrelated interpretations, but only for high-imagery proverbs. In Experiment II, subjects wrote interpretations of the proverbs and then received either the proverb subject-noun or a brief story as a prompt. As was the case for the interpretations in Experiment I, the stories did not share any major vocabulary or propositional structure with their proverb source. Nonetheless, the stories were as effective as the nouns. Also, quality of proverb interpretation and of recall performance were positively related, with the correlations involving low-imagery proverbs, and stories, tending to be higher. Both experiments provided support for the conceptual-base notion, and underlined the importance of interpretive context, but more definitive evidence is needed.     

Partial differential feedback: An on-line training configuration for the optimization of multidimensional cue learning

The present paper describes a PDP-9 computer configuration arranged for experimental research into the acquisition of judgmental skill, but designed to overcome certain deficiences noted in stimulus-response-outcome (SRO) paradigms. The configuration departs radically from traditional approaches in that (a) the stimulus is placed under S control; (b) the requirement for a “response” is eliminated; (c) outcome feedback is a continuously changing function of the multiattribute stimulus settings under the control of S; and (d) the configuration makes possible the rapid learning of an essential feature of such learning tasks, namely the partial derivatives of the criterion or outcome variable with respect to each of the stimulus attributes.     

Collateral behavior of the pigeon during conditioned suppression of key pecking

Ethological recording procedures measured collateral behavior in pigeons whose key-pecking performance was suppressed during a tone that ended with unavoidable electric shock. Independent recordings of gross behavior were made by two observers throughout 60-sec intervals immediately before, during, and after tone presentation. Results indicated significant reductions in the frequency of collateral movements and an increase in the time between successive movements during tone presentations. These effects were observed in all subjects, despite differences in the sequential patterns of behavior. Only partial recovery of the behavior evidenced before tone presentation was found during a 60-sec interval following shock. It was concluded that conditioned suppression procedures caused the bird to “freeze” during tone presentation and in this fashion produced a general inhibitory effect on ongoing overt activity, including key pecking.     

Predetermination of test weights

Derivations are presented relating the length of a test to its weight in a composite. Tests of varying length are constructed so that their weights will be of predetermined magnitudes, and the results compared with expectations. Weighting schemes involving standard deviations of raw scores and of true scores are compared. An important secondary derivation is presented from which it is possible to estimate test reliability knowing only the relative length of a test, its shortened form, and the standard deviation of each.     

Differential Effects of Racial Socialization Messages for African American Adolescents: Personal Versus Institutional Racial Discrimination

Racial socialization is one factor known to attenuate the negative consequences of racial discrimination on adolescents’ anger and depressive symptoms. However, little is known about whether racial socialization messages addressing cultural and racial pride and messages preparing youth for racial discrimination and racial barriers function differently depending upon whether adolescents perceive personal versus institutional racial discrimination. Thus, the present study examined whether racial socialization messages emphasizing racial pride and racial barriers protected against anger and depressive symptoms for African American adolescents’ experience of personal and institutional racial discrimination. Participants were a community sample of 106 urban African American adolescents (57 % girls; mean age = 15.41) residing in a large metropolitan area. Regression analyses revealed that personal racial discrimination was positively associated with anger for youth reporting low cultural pride reinforcement, and positively associated with depressive symptoms for youth reporting low cultural alertness to discrimination; there were no associations between personal racial discrimination and anger or depressive symptoms for youth reporting high racial socialization messages. Neither cultural pride nor racial barrier racial socialization message protected against institutional racial discrimination. Findings suggest that the protective effects of racial socialization messages vary based on the type of racial discrimination adolescents experience.