Classical conditioning of the nictitating membrane response of the lemon shark (Negaprion brevirostris)

An experimental group of lemon sharks received 100 daily presentations of light flash as the conditioned stimulus (CS) and electric shock as the unconditioned stimulus (US) in a classical conditioning situation. The conditioned responses (CRs) and unconditioned responses (URs) under observation consisted of extensions of the nictitating membrane. Separate control groups received either (a) no CS or US, (b) CS-alone, or (c) completely random presentations of CS and US. Few CRs occurred in the experimental group at the outset of conditioning, but the percentage of CRs during the second half of the first acquisition session exceeded 95%. Conditioning stabilized above 95% CRs during Acquisition Sessions 3 through 7. These responses could not be attributed to pseudoconditioning, sensitization, or other nonassociative factors. When the experimental group was subsequently given six CS-alone sessions, the course of extinction was gradual. Most results seemed similar to those previously obtained during classical conditioning of the nictitating membrane in rabbits.     

A high-speed algorithm for computing conditional probabilities of substrings of sequentially observed data

An algorithm is described that computes relative frequencies of occurrence of all arbitrarily long substrings of sequential data, such as are obtained from experiments in learning/memory and verbal interaction. The algorithm offers high speed and provides systematization for the computation of empirical conditional probabilities. Use of this algorithm allows application of probabilistic and information theoretic disciplines to reveal dependencies between events separated arbitrarily in time.     

The effect of manipulated success ratios on task preference

The hypothesis that success influences task preferences was tested by subjecting 230 Ss to three different success-failure reinforcement schedules and observing subsequent preferences for the tasks concerned. Success ratios of 85-15%, 70-30%, and 50-50% in tasks dealing with unpreferred stimuli were used. Results supported the hypothesis: the probability of change in task preference was greatest under high success reinforcement ratio conditions.     

Localization of a peripheral target during parametric adjustment of saccadic eye movements

The aim of the experiment was to find out whether saccadiceve movements have any effect on perceived visual directions. ihe method was to alter the parameters of the oculomotor system so that the eye movement made in response to a peripheral target was inappropriate to the retinal locus of its image. It was found that this procedure had no effect on the perceived location of the peripheral target; and it was concluded that a specific retinal locus is more or less rigidly associated with a corresponding visual direction, but not with a particular magnitude of ocular rotation.     

Vocational Preference Inventory High Point Codes and Educational Preferences

This study reports normative data describing the combinations of various VPI high point codes associated with educational preferences classified into one of six of Holland's occupational environments and an undecided category. Eight hundred thirty-one male and 129 female college freshmen were queried regarding their educational preferences and were administered the VPI directly prior to college enrollment. The comparisons between preferences and VPI combinations revealed that Intellectual and Realistic, Social and Enterprising, Conventional and Enterprising, and Social and Artistic, seem to go together frequently for male students. The female sample revealed that Social and Artistic VPI codes were common.     

A computer-controlled system for training and testing primates

The hardware and software for a computer-controlled training and testing system for primates are described. The computer (DDP-116 in the Computer-Controlled Psychology Laboratory at Carnegie-Mellon University) controls all stimulus presentation, reinforcement, and records data in a form ready for analysis on a larger computer.     

Shorter articles and notes noise and the shifting of attention

An experiment was carried out to test the hypothesis that performance on a task which involves a shift of attention between spatially separated sources would be lower under noise conditions than one which involved no such shift. The results indicated that the hypothesis was not proved; rather they showed that the subject's performance on the shift of attention task was better under noise than under quiet. An attempt is made to put forward possible reasons for this occurrence.     

Mathematical analysis of the durations of reinforced inter-response times during variable interval reinforcement

In a free-responding situation in which reinforcements are scheduled by a variable interval program, the durations of reinforced inter-response times are shown to be a function of the durations of all inter-response times produced by S and of the frequency of reinforcement.Based on a portion of the author's doctoral dissertation, and supported in part by an NIMH predoctoral research fellowship. Suggestions by W. K. Estes increased the intelligibility of this paper.     

Religion and Public Opinion Toward Same‐Sex Relations,Marriage, and Adoption: Does the Type of Practice Matter?

This study examines how religion's impact on Americans’ attitudes toward same‐sex practices varies by the type of practice being considered. We theorize that same‐sex romantic and family practices such as sexual relations, marriage, and adoption represent distinct practice types, differing in degrees of legality, cultural legitimacy, and in their internal power dynamics. Consequently, we expect that Americans view each practice type somewhat differently and their opinions on each may be influenced by religion in distinctive ways. Drawing upon national‐level data, we estimate and compare the relative net effects of a comprehensive battery of religious measures on support for gay sex, marriage, and adoption, both for the full sample and across religious traditions. Analyses demonstrate that public opinion toward gay sexual relations is more strongly related to religious practice and theological conservatism compared to attitudes regarding same‐sex marriage or adoption. Moreover, frequent religious practice and conservative theological beliefs about the Bible tend to be more strongly associated with attitudes toward same‐sex relationships for evangelicals, compared to mainline Protestants and, to a lesser extent, Catholics. Findings ultimately affirm that the type of same‐sex practice being considered (sex, marriage, or adoption) serves to moderate religions’ impact on Americans’ support for such practices.     

Family Formation and Returning to Institutional Religion in Young Adulthood

Institutional religious involvement wanes during young adulthood, but evidence suggests life‐course factors such as family formation bring people back to religion. Using the National Longitudinal Study of Adolescent to Adult Health (Waves 1, 3, and 4), we examine how often young adults who were involved in institutional religion as adolescents return—measured by religious service attendance and religious affiliation—after leaving in emerging adulthood, and how this return is patterned by family formation. The majority of young adults who leave do not return to regular religious service attendance, regardless of their family formation. But single parents, married parents, and childless married individuals are more likely, and childless cohabiting couples less likely, to return to religious communities than those who are both single and childless. Only married parents are more likely than childless singles to reaffiliate, though there is marginal evidence that childless married adults may also be more likely. Thus, the institutions of religion and family are still linked, even though overall levels of religious return are not as high as expected.