Preference for mixed-interval versus fixed-interval schedules

Pigeons were trained on a two-link concurrent chain schedule in which responses on two keys were reinforced according to independent variable-interval schedules by the production of a change in key color. Further responses on the key on which the stimulus change had been produced gave a single food reinforcement and a return to concurrent variable-interval conditions. On one key the terminal link was a two-valued mixed-interval schedule, while on the other, the terminal link was a fixed-interval schedule. When the mixed-interval values were kept constant and the fixed-interval values varied, relative response rates in the initial concurrent links matched relative reinforcement rates in the terminal links when these were computed from cubic transformations of the reciprocals of the intervals comprising the terminal link schedules.     

Punished and Nonpunished Responding in A Multiple Schedule in Humans: A Brief Report

Four male subjects responded on a multiple schedule in which responding was maintained by a random interval 20-sec (RI20) schedule of point presentation. Responding was suppressed in alternating components by an added variable ratio 30 (VR30) schedule of point subtractions. Each component was accompanied by distinctive stimulus lights. Subjects were exposed to the multiple schedule from the initial session. Two subjects experienced four 50-min sessions daily (Experiment 1) and the other two subjects participated in one 50-min session daily (Experiment 2). Once responding in the punished components had stabilized, responding in the nonpunished components continued to increase across sessions. Nonpunished responding did not stabilize even after as many as 36 sessions. These results are discussed in the context of previous studies using animals which employed multiple schedules with punished and nonpunished response contingencies.

     

Thingly hermeneutics/Technoconstructions

Within the Euro-American community of philosophers relating hermeneutics to science there is a considerable disagreement about where hermeneutics may be located. The older traditions hold that hermeneutics apply to and are limited to the social, cultural, and historical dimensions of science. But newer approaches claim that hermeneutics applies to the very praxis of science and to the constitution of scientific objects. This paper sides with the latter perspective and argues that a tendency to retain vestigial positivist interpretations of science keeps the older tradition from seeing hermeneutics as deeply embedded in science praxis. After arguing this point historically, I turn to a hermeneutic recuperation of science, first by drawing from the hermeneutic approach of Joseph Rouse, and then by the hermeneutic constructionism of Bruno Latour. I finally turn to what I term technoconstruction in science, particularly in imaging processes, to show concrete cases of the hermeneutic preparation of scientific objects. I conclude that contemporary science has exceeded its earlier modernist framework and now operates in a constructionist-hermeneutic framework.     

The Patient Self-Determination Act and Advance Directives: Snapshots of Activities in a Tertiary Health Care Center

This study describes the results of a retrospective review of patients' charts who had an advanced directive (AD) and who were hospitalized in a tertiary, acute care teaching hospital. The purpose of the review was to understand from clinical, sociological, ethical and legal perspectives the nature and utility of ADs. Findings and implications of the review are discussed in terms of: patient demographics; diagnoses; quality of ADs; influence of ADs on clinical decisions; and legal aspects of ADs.     

Children‘s ability to remember an occurrence of a repeated event

The authors summarise the findings of four recent experiments whichexamined childrens capacity to remember a particular occurrence of arecurring event. Issues discussed include the timing of the interview, thetype of errors, the questioning techniques, the age of the child, theconsistency of the childs account, and the impact of an interveninginterview. Implications for professionals who conduct investigatory orevidentiary interviews with child witnesses are discussed and suggestionsfor future research are also offered.     

Exposure-based models of human parsing: Evidence for the use of coarse-grained (nonlexical) statistical records

Several current models of human parsing maintain that initial structural decisions are influenced (or tuned) by the listener's or reader's prior contact with language. The precise workings of these models depend upon the grain, or level of detail, at which previous exposures to language are analyzed and used to influence parsing decisions. Some models are premised upon the use of fine-grained records (such as lexical cooccurrence statistics). Others use coarser measures. The present paper considers the viability of models based exclusively on the use of fine-grained lexical records. The results of several studies are reviewed and the evidence suggests that, if they are to account for the data, experience-based parsers must draw upon records or representations that capture statistical regularities beyond the lexical level. This poses problems for several parsing models in the literature.Aspects of this work were supported by ESRC grant No. R0023 4062 to Don Mitchell, by a Spanish Government grant DGICVT No. PB-92-0656-C04-02 to Fernando Cuetos, and by the Belgian National Fonds voor Wetenschappelijk Onderzoek, of which Marc Brysbaert is a Research Associate. We are grateful to Chuck Clifton, Barbara Hemforth, Martin Pickering, Matt Traxler, and an anonymous reviewer-all of whom made helpful comments on an earlier draft of the paper.     

The availability heuristic in person identification: The sometimes misleading consequences of enhanced contextual information

Three field studies investigated the effects of post-exposure cognitions on person identification. Subjects' beliefs that they could identify someone were significantly increased by the presentation of new information and the rehearsal of old information about the person. Misidentification errors increased as the lengths of the initial exposure duration increased and when subjects received additional contextual information about the target. These frequent misidentifications may reflect the misattribution of familiarity from enhanced contextual knowledge to familiarity arising from perceptual knowledge. Further, performance was enhanced when the identification task capitalized on 'transfer-appropriate rehearsal' post-event strategies. Ancillary findings contradicted research on 'verbal overshadowing', and the relationship between identification accuracy and confidence. The results were generalized to real-world situations that encourage post-event cognitions by eyewitnesses.