Control of CRT intensity via Apple II software

An inexpensive, easy-to-build device for the Apple II microprocessor is described. The modification permits software control of four levels of relative screen intensity (contrast) settings for any video monitor. The relationship of the technology to choice reaction time and perception research is briefly indicated. Principles governing operation of the modification are also discussed. Finally, a set of step-by-step instructions for building the device is provided.     

Feature-positive effect in adults and attention to portion of stimulus array

In three experiments, adult humans were tested in a feature-positive or feature-negative simultaneous symbol task. In Experiment 1, some persons focused on the correct side of the stimulus cards, whereas other persons focused on the not-correct side of the stimulus cards. The feature-positive group learned faster than the feature-negative group did in the correct side condition; the feature-negative group learned faster than the feature-positive group did in the not-correct side condition. In Experiments 2 and 3, all persons focused on both the correct and not-correct sides of the stimulus cards. Under these circumstances, feature-positive and feature-negative performances were comparable. These results indicated that the usual superiority of feature-positive over feature-negative learning results from a tendency to attend to only a portion of the stimulus array.     

A review of the tip-of-the-tongue experience

The tip-of-the-tongue experience (TOT) has intrigued psychologists for nearly a century. R. Brown and McNeil (1966) provided the first systematic exploration of the phenomenon, and the findings since their seminal study suggest that TOTs (a) are a nearly universal experience, (b) occur about once a week, (c) increase with age, (d) are frequently elicited by proper names, (e) often enable access to the target word's first letter, (f) are often accompanied by words related to the target, and (g) are resolved during the experience about half of the time. Important questions remain concerning TOTs: (a) Are emotional reactions necessary, (b) do only low frequency targets elicit TOTs, (c) do TOTs reflect incomplete target word activation or interference from related words, and (d) do spontaneous retrievals really occur? A more precise definition of the TOT experience is needed, as well as greater uniformity in the information gathered during TOTs.     

Reducing the effects of adjacent distractors by narrowing attention.

Three experiments explored the gradual narrowing of visual attention to a letter target when other letters were positioned close by. The method by which attention was narrowed involved presenting a digit target immediately prior to the latter target and in the same location for progressively shorter durations and requiring the subject to identify both the digit target and the letter target before responding. The response time data from the first 2 experiments indicated that shorter durations of the digit reduced the amount of information processed from noise letters positioned on either side of the letter target. In the third experiment, in which separation of letters was increased slightly, the response times indicated that the information from flanking noise letters may have been virtually eliminated.     

Engagement and recruitment for family therapy research in community settings

Based on the recruitment experience in a family therapy research project with heroin addicts, this paper explores the difficulties of researcher networking with other social service agencies. Concepts from contextual family therapy are used to explore four general areas that contribute to successful intra-agency relationships: 1) Evaluating the nature of larger system relationships; 2) identifying the resources and needs of a clinic; 3) joining with the counseling staff; and 4) addressing the impact of public policy and ideology on clinic life. A case of engaging one clinic is presented and nine guidelines for engaging large community settings for participation in family therapy research are offered. These areas are considered in light of the relational dynamics that arise when working with multiple social service systems.An earlier version of this paper was presented at the American Family Therapy Association conference in Washington, DC, June 1986. The authors are grateful to the recruitment staff of the Intergenerational Family Therapy Project: Guillermo Lopez, Bart Rubin, Sharara Godfry, and Armando Chenyek. This research was supported in part by a grant to Guillermo Bernal from the National Institute on Drug Abuse (DA03543).     

Back to basics: Percentage agreement measures are adequate, but there are easier ways

Percentage agreement measures of interobserver agreement or "reliability" have traditionally been used to summarize observer agreement from studies using interval recording, time-sampling, and trial-scoring data collection procedures. Recent articles disagree on whether to continue using these percentage agreement measures, and on which ones to use, and what to do about chance agreements if their use is continued. Much of the disagreement derives from the need to be reasonably certain we do not accept as evidence of true interobserver agreement those agreement levels which are substantially probable as a result of chance observer agreement. The various percentage agreement measures are shown to be adequate to this task, but easier ways are discussed. Tables are given to permit checking to see if obtained disagreements are unlikely due to chance. Particularly important is the discovery of a simple rule that, when met, makes the tables unnecessary. If reliability checks using 50 or more observation occasions produce 10% or fewer disagreements, for behavior rates from 10% through 90%, the agreement achieved is quite improbably the result of chance agreement.     

Conceptual preference for thematic or taxonomic relations: A nonmonotonic age trend from preschool to old age

Two experiments examined the development of conceptual preference for either thematic (functional) or taxonomic relationships in a match-to sample task. In Experiment 1 twenty subjects from each of five age groups—preschool to old age—completed a method of triads preference test where they were forced to choose a thematic or taxonomic match. Young and old individuals preferred the thematic parings while school age and college adults preferred the taxonomic matches. Although the Age × Preference relation was pronounced, the majority of subjects at all ages could provide adequate justification of both the preferred and nonpreferred relationship. In addition, kindergarten subjects in Experiment 2 could readily be trained to respond on the basis of the nonpreferred mode. These data suggest that the pervasive shift in conceptual responding from syntagmatic to paradigmatic, thematic to taxonomic, etc., represents a change in preference rather than a shift to a fundamentally new way of organizing knowledge.     

Apparatus for collecting voice chronography data

The conversion of speech into on-off pulse patteras representing talk spurts and pauses is a major tool used by psychologists in analyzing interactive communications behavior. We describe a conversion method and a means for interfacing its output with a computer, which allows the collection of large amounts of speech data from one or more sources. The major improvement over prior art is the ability to reject cross talk between neighbor speakers while permitting the detection of simultaneous speech. In the evaluation of the performance of the apparatus, no errors were detected for single-party speaking. Infrequent small errors occurred in the detection and duration of talk spurts and pauses during two- and three-party speaking, but these would probably be acceptable in most applications.