Effects of ethanol on reinforced variations and repetitions by rats under a multiple schedule.

Response sequences emitted by five Long-Evans rats were reinforced under a two-component multiple schedule. In the REPEAT component, food pellets were contingent upon completion of a left-left-right-right (LLRR) sequence on two levers. In the VARY component, pellets were contingent upon variable sequences (i.e., a sequence was reinforced only if it differed from each of the previous five sequences). The rats learned to emit LLRR sequences in the REPEAT component and variable sequences in VARY. Intraperitoneal injections of ethanol (1.25, 1.75, and 2.25 g/kg) significantly increased sequence variability in REPEAT, thereby lowering reinforcement probability, but had little effect on sequence variability in the VARY component. These results extend previous findings that alcohol impairs the performance of reinforced repetitions but not of reinforced variations in response sequences.     

The reliability of a computer interview for drug use/abuse information

A computer interview was developed to collect information about drug use/abuse from high school students. Responses to this interview were compared with those obtained from an identical paper-and-pencil questionnaire given to the same students, in counterbalanced order. Results were comparable for the two methods, but missing data and logically inconsistent answers obtained with the paper-and-pencil questionnaire were not possible with the computer interview. The overwhelming majority of respondents preferred the computer interview as a means of data collection.     

Thinking critically in medicine and its ethics: relating applied science and applied ethics

ABSTRACT While interest in philosophy and medicine has burgeoned in the past two decades, there remains a need for an analysis of the intellectual activity embodied in good medical practice. In this setting, ethical and scientific decision-making are complexly interrelated. The following paper, collaboratively written by physicians and philosophers, presents a view of applied (clinical) science and applied ethics. Making extensive use of illustrations drawn from routine case material, we seek to indicate a variety of philosophic issues to be found in daily practice, elucidate various levels of critical reasoning within the medical setting, and demonstrate a remarkable similarity between medical and ethical decision-making.     

BELIEFS OF A CHRISTIAN MINISTER IN LIGHT OF CONTEMPORARY SCIENCE

Abstract. This paper states the author's understanding of the doctrines of the Christian faith in the light of her scientific background and her interpretation of current evolutionary, neuropsychologi–cal, and other scientific theories. It contains the actual ordination vows and her response to them, based upon an outline of questions suggested by the United Church of Christ.     

Teaching autistic children to use extra-stimulus prompts

Autistic children often do not transfer from extra-stimulus prompts, and thus do not utilize a frequent learning aid. It has been hypothesized that this is due to stimulus overselectivity; a failure to respond to simultaneous multiple cues. This study was designed to determine if autistic children who initially respond only to single cues can be taught a set to respond to two cues and subsequently utilize an extra-stimulus (pointing) prompt. Four autistic children were pretested to determine if they could learn a complex visual discrimination by either trial and error or an extra-stimulus prompt fading procedure. Since they did not, the children were then taught to respond to two cues through a multiple-cue training procedure and subsequently tested to determine if they could now utilize a pointing prompt. Results indicated that while all four children initially did not transfer from an extra-stimulus (pointing) prompt, they did so subsequent to multiple-cue training. The results are discussed in terms of implications for treatment (remediating overselectivity) and in relation to normal child development.     

Constraints on the visual accuracy of drawings produced by young children

Errors made by young children when they are asked to draw a model were investigated in two studies. In the first study, the experimenter asked 5- and 8-year-old children to draw a cup that had a flower decal (transfer) attached to its outside surface, attached to its inside surface or positioned beside it. The 8-year-old children in all conditions produced visually accurate drawings. The 5-year-old children produced visually accurate drawings when the flower decal was positioned beside the cup and when the flower decal was attached to the inside surface of the cup but not when the flower decal was attached to the cup's outside surface. In the second study, 5- and 8-year-old children were asked to draw a cup that had either an intact or a broken handle. The handle area of the cup was either in view or not in view. The 5- and 8-year-old children performed comparably in this experiment. The children had difficulty producing accurate copies of the model only when the cup had a handle and the handle was not in view. Taken together, these studies indicate that 5-year-old children are more likely to produce visually accurate drawings than has previously been supposed. Difficulty in producing accurate drawings occurred when drawing rules and drawing conventions interfered with the task.     

A watched pot sometimes boils: a study of duration experience

The ‘watched pot’ phenomenon — the lengthening of duration experience when one is attentively and perhaps impatiently waiting for some event to occur — was studied in three experiments. In them, each observer attended for a duration of 270 sec to a liquid-containing beaker on an electrical burner. Observers who were told that the experiment concerned time perception (prospective paradigm) reproduced the duration as longer than those told that it concerned visual perception (retrospective paradigm). In the prospective paradigm, reproductions were longer if the liquid did not boil than if it did, and an interruption (task-unrelated questioning) shortened reproductions if the liquid did not boil but had no effect if it did. In the retrospective paradigm, if there was boiling or questioning or both, reproductions were longer than if there was neither. Results have implications for hypotheses about duration experience.     

Within-compound associations in a variety of compound conditioning procedures

Three experiments used a flavor-aversion preparation to demonstrate the occurrence of within-compound associations in various conditioning procedures. In Experiment 1 rats first received two separate two-flavor compounds, each followed by a mild US. They then received one element from one compound paired with a strong US and one element from the other compound nonreinforced. A subsequent choice test of the other two flavors from the compounds revealed that the consumption of each test flavor reflected the conditioning history of the element with which it had been paired. Rats drank less of the flavor whose associate had been paired with the strong US than of the flavor whose associate had been nonreinforced. In Experiment 2 within-compound associations were observed using a similar design in a blocking procedure in which one element from each of the two compounds was conditioned previously. Experiment 3 identified within-compound associations in a procedure where reinforced single element presentations were intermixed with nonreinforced compound presentations, as in a conditioned inhibition paradigm. These results suggest that within-compound associations occur in several important conditioning procedures which use multiple CS presentations.