An Apple II-based slide-projector laboratory

We describe the software and hardware of a laboratory running under UCSD Pascal on an Apple II computer. The system includes: two random-access projectors and two standard projectors, all equipped with tachistoscopic shutters; two filter wheels; a voice key; a tone generator; and eight response boxes. The laboratory can be used for any experiment in which visual stimuli are to be presented and in which precise display times, reaction times, and luminances are required. It is particularly well suited to picture-perception and picture-memory experiments.     

Temporal factors influencing the pigeon's successive matching-to-sample performance: sample duration, intertrial interval, and retention interval

A successive matching-to-sample procedure that entails the sequential presentation of sample and test stimuli and the monitoring of response rates in a go/no-go discrimination of matching and nonmatching stimuli was studied as an alternative to the familiar delayed-matching paradigm of animal short-term memory. Three within-subject experiments studied the effects of sample duration (1 to 12 seconds), intertrial interval (5 to 50 seconds), and retention interval (1 to 50 seconds) on the pigeon's successive-matching performance. The results revealed that retention was (a) an increasing function of sample duration and intertrial interval, and (b) a decreasing function of retention interval. These results were in accord with those of more traditional short-term memory paradigms, and reveal the suitability of the successive-matching procedure for studying memory processes.     

Effect of multiple images on associative learning

The present research investigated the effects of multiple images on associative learning. In Experiment 1, subjects formed either a noninteractive image of two words, a single interactive image, a multiple interactive image consisting of multiple copies of the same image, or a multiple interactive image consisting of different images. In Experiment 2, the different multiple images were formed across trials instead of simultaneously during the same trial. Both experiments showed that, although interactive images are superior to noninteractive images, there is no reliable facilitation from multiple images as compared with single images. The results were discussed in terms of the variable-encoding hypothesis and previous findings that multiple retrieval paths facilitate verbal learning.     

THE DISTINCTIVENESS EFFECT IN SOCIAL CATEGORIZATION:

Abstract— Three studies tested the hypothesis that people assume that the identities of other people are tied more closely to their distinctive than to their nondistinctive traits. In Studies 1 and 3, subjects predicted the preferences of a target person who was a member of both a statistically distinctive and a statistically nondistinctive category (e g, sky diver and tennis player). In Study 2, subjects judged the degree of interpersonal similarity between pairs of people sharing distinctive as opposed to nondistinctive category memberships. Consistent with the hypothesis, subjects linked targets with their more distinctive traits and assumed targets would be more similar to people who shared their distinctive traits than to people who shared their nondistinctive traits. The implications of this distinctiveness effect for an understanding of stereotyping are explored.     

A feminist naturalized philosophy of science

Building on developments in feminist science scholarship and the philosophy of science, I advocate two methodological principles as elements of a naturalized philosophy of science. One principle incorporates a holistic account of evidence inclusive of claims and theories informed by and/or expressive of politics and non-constitutive values; the second takes communities, rather than individual scientists, to be the primary loci of scientific knowledge. I use case studies to demonstrate that these methodological principles satisfy three criteria for naturalization accepted in naturalized philosophy of science, and allow for the differential assessment of episodes in which values and sociopolitical factors inform, or contribute to the adoption of, theories for which there is sufficient evidential warrant — and episodes in which such factors inform, or contribute to the adoption of, theories for which there is not. I contend that in terms of their empirical and normative import, these principles constitute a further naturalization of the philosophy of science.I am grateful to Richmond Campbell, Ingvar Johansson, Hildur Kalman, Peter Machamer, James Maffie, Jack Nelson, Elizabeth Potter, Phyllis Rooney, Joseph Rouse, and Nancy Tuana for constructive criticisms of earlier drafts. An earlier version was presented to the Nordiskt Nätverk för Feministisk Epistemologioch Feministisk Vetenskapsteorito, and the Institutionen för Filosfi och Vetenskapsteorito at Umeå Universitet, in October 1994. I am grateful to members of these audiences for challenging and insightful criticisms.     

Generalization of Habituation and Intrinsic Sensitization in the Leech

Using the shortening reflex of the medicinal leech Hirudo medicinalis we examined stimulus generalization of habituation learning. Preparations received mechanosensory stimulus at two positions on the leech body wall, one site used to carry out habituation training and a second novel site to test for generalization of habituation. After training, the specific mechanosensory neurons activated by each stimulus were assessed using intracellular recordings. As expected, the closer the two sites were to each other, the greater the degree of generalization of habituation at the novel site and the more sensory cells were shared. However, a form of behavioral facilitation was observed at the trained site that resembled behavioral sensitization, but differed from the standard sensitization process in several respects. (1) Facilitation was induced by stimulation of the novel site before habituation training at the trained site, although the stimulus intensity at the novel site was equivalent to the training stimuli and was not the strong, noxious stimuli that normally induce sensitization. (2) The magnitude of the facilitating effect was proportional to the proximity of the novel and trained stimulation sites. (3) Although behavior at the trained site was facilitated, behavior at the novel site was habituated, indicating that the induced behavioral facilitation did not generalize throughout the animal, as normally occurs during sensitization, but was limited to a single stimulus–response pathway.     

Hiring family therapists for a research project via videotaped interviews: A brief report

The authors describe an interview procedure devised for use in hiring therapists for a research and demonstration project in which the employers viewed videotaped interviews of applicants responding to a standard set of questions posed by an on-site researcher/interviewer. The approach is considered potentially useful for agencies to use in hiring therapists with a systemic orientation.