Observing behavior in a computer game.

Contingencies studied in lever-pressing procedures were incorporated into a popular computer game, "Star Trek," played by college students. One putative reinforcer, the opportunity to destroy Klingon invaders, was scheduled independently of responding according to a variable-time schedule that alternated unpredictably with equal periods of Klingon unavailability (mixed variable time, extinction schedule of reinforcement). Two commands ("observing responses") each produced stimuli that were either correlated or uncorrelated with the two components. In several variations of the basic game, an S-, or bad news, was not as reinforcing as an S+, or good news. In addition, in other conditions for the same subjects observing responses were not maintained better by bad news than by an uninformative stimulus. In both choices, more observing tended to be maintained by an S- for response-independent Klingons when its information could be (and was) used to advantage with respect to other types of reinforcement in the situation (Parts 1 and 2) than when the information could not be so used (Part 3). The findings favor the conditioned reinforcement hypothesis of observing behavior over the uncertainty-reduction hypothesis. This extends research to a more natural setting and to multialternative concurrent schedules of events of seemingly intrinsic value.     

Responding of pigeons under variable-interval schedules of signaled-delayed reinforcement: effects of delay-signal duration.

Two experiments with pigeons examined the relation of the duration of a signal for delay ("delay signal") to rates of key pecking. The first employed a multiple schedule comprised of two components with equal variable-interval 60-s schedules of 27-s delayed food reinforcement. In one component, a short (0.5-s) delay signal, presented immediately following the key peck that began the delay, was increased in duration across phases; in the second component the delay signal initially was equal to the length of the programmed delay (27 s) and was decreased across phases. Response rates prior to delays were an increasing function of delay-signal duration. As the delay signal was decreased in duration, response rates were generally higher than those obtained under identical delay-signal durations as the signal was increased in duration. In Experiment 2 a single variable-interval 60-s schedule of 27-s delayed reinforcement was used. Delay-signal durations were again increased gradually across phases. As in Experiment 1, response rates increased as the delay-signal duration was increased. Following the phase during which the signal lasted the entire delay, shorter delay-signal-duration conditions were introduced abruptly, rather than gradually as in Experiment 1, to determine whether the gradual shortening of the delay signal accounted for the differences observed in response rates under identical delay-signal conditions in Experiment 1. Response rates obtained during the second exposures to the conditions with shorter signals were higher than those observed under identical conditions as the signal duration was increased, as in Experiment 1. In both experiments, rates and patterns of responding during delays varied greatly across subjects and were not systematically related to delay-signal durations. The effects of the delay signal may be related to the signal's role as a discriminative stimulus for adventitiously reinforced intradelay behavior, or the delay signal may have served as a conditioned reinforcer by virtue of the temporal relation between it and presentation of food.     

INCREASING SPONTANEOUS LANGUAGE IN THREE AUTISTIC CHILDREN

A time delay procedure was used to increase spontaneous verbalizations of 3 autistic children. Multiple baseline across behaviors designs were used with target responses, selected via a social validation procedure, of two spontaneous responses (“please” and “thank you”) and one verbally prompted response (“you're welcome”). The results indicate gains across target behaviors for all children, with occurrence across other stimuli and settings. These gains were validated socially with 10 adults. Furthermore, increases in appropriate language had no effect on levels of inappropriate speech.     

ENHANCING CONVERSATION SKILLS IN PATIENTS WITH ALZHEIMER'S DISEASE USING A PROSTHETIC MEMORY AID

The effectiveness of teaching Alzheimer's disease subjects to use a prosthetic memory aid when conversing with familiar partners was evaluated. Effects of the training of three topics by caregivers was assessed in daily probes with the experimenter and twice weekly probes with a familiar conversational partner. All 3 subjects learned to use the memory aid with both conversational partners and improved the quality of their conversational content. Subjects made significantly more statements of fact and fewer ambiguous utterances after training on each topic according to a multiple baseline design. All subjects also generated novel, untrained statements in conversations with both partners. Treatment effects were maintained at high levels throughout training and at 3- and 6-week followup sessions. Naive judges rated baseline and posttreatment conversational samples as significantly improved on all eight conversational dimensions.     

Humans' sensitivity to variation in reinforcer amount: Effects of the method of reinforcer delivery

Two experiments examined human subjects' sensitivity to variation in reinforcer amount under different methods of reinforcer delivery. Subjects chose between schedules varying in terms of amount and/or delay of reinforcement, the reinforcer being points exchangeable for money. In Experiment 1, reinforcer amount was manipulated by varying the monetary value of the points across conditions while the number of seconds of access to a consummatory response remained constant. Choice was strongly sensitive to reinforcer amount and indicative of self-control, as in previous experiments. In Experiment 2, reinforcer amount was manipulated by automatically delivering different numbers of points during the amount period, and the consummatory response was eliminated. Sensitivity to variation in reinforcer amount was significantly lower than in Experiment 1. Furthermore, the subjects in Experiment 2 exhibited significantly less self-control than did the subjects in Experiment 1. Humans' sensitivity to variation in reinforcer amount appears to be affected by factors that enhance the discrimi-nability of the consequences of responding.     

Response patterns and cardiovascular effects during response sequence acquisition by humans.

The effects of temporal delays imposed between successive responses and of vitamin C administration were examined on the acquisition of response sequences and on cardiovascular reactivity during sequence acquisition. Thirteen adult subjects (6 female, 7 male), in good health, gave written consent prior to participating in 12 weekly 45-min sessions. Points, exchanged for money after each session, were presented when subjects completed 15-response sequences on a touch-sensitive three-response keypad. A position counter increased from 0 to 14 as subjects emitted correct responses in the sequence. Four novel 15-response sequences were presented each session. No delays were imposed between successive responses during the acquisition of one sequence; delays were imposed immediately following each response during the acquisition of a second sequence, thereby delaying response feedback; delays were imposed following feedback during acquisition of a third sequence, resulting in the removal of the stimulus correlated with sequence position; and, as a control condition, delays were imposed following feedback, but stimuli correlated with sequence position were reinstated prior to the next response during acquisition of a fourth sequence. Subjects were exposed to one of two delay durations (0.2 and 0.5 or 0.5 and 1.0 s) each session, and delay durations alternated every session. During Weeks 5 to 8, subjects received 3 grams of vitamin C per day, whereas during Weeks 1 to 4 and 9 to 12, subjects received placebo under single-blind conditions. All subjects acquired the sequences, as evidenced by decreasing percentages of incorrect responses across trials. When temporal delays were imposed between successive responses during sequence acquisition, acquisition efficiency was enhanced. Examination of response latencies suggested that the status of preceding responses (i.e., correct or incorrect) rather than the status of the position counter influenced subsequent responding. Cardiovascular effects were inversely related to the length of the temporal delay. Neither cardiovascular reactivity or sequence acquisition were related to vitamin C administration.     

Participatory management: Maintaining staff performance in a university housing cooperative

To apply behavior analysis to normal adults in non institutional settings, we may have to encourage their participation in the design and implementation of behavioral technology. This study evaluates a technology by which the members of a student housing cooperative manage their own staff with a minimum of supervision by one of the program designers. This staff management system consisted of prompts, self-reports, spot checks, and contingent rent reductions. Six resident staff members performed substantially more of their assigned tasks when this system was used. In addition, the management system was acceptable to the members, was affordable, and maintained high levels of staff performance during a 5-year follow-up. Participation by the members in the design and implementation of this system appears to have been useful in helping the behavior analysts to develop an unusually durable management system.     

TEACHING MEMORIZED SPELLING WITH A MICROCOMPUTER: TIME DELAY AND COMPUTER-ASSISTED INSTRUCTION

A computer-assisted instruction program was evaluated that used a constant time-delay procedure to teach 5 students 18 spelling words. In addition to delivering the instructional procedure, the program managed the presentation of training content based on individual student responding and collected instructional data on individual student performance. The procedure was effective at teaching 4 of the 5 students the words, and generalization occurred from the computer-delivered keyboard response format to a teacher-delivered hand-written response format. Maintenance data varied among the students. The study demonstrated the feasibility of using microcomputers to deliver time-delay instruction in special education classrooms and suggested several research questions related to specific features of microcomputer-delivered time-delay instruction.     

INCREASING AUTISTIC CHILDREN'S DAILY SPONTANEOUS SPEECH

We investigated the effectiveness of teaching parents of 3 autistic boys to use a time delay procedure to increase their children's appropriate spontaneous speech in several naturally occurring daily settings (e.g., saying “good morning” in the morning). Generalization across settings and within settings across persons and locations was assessed. Variation in the children's spontaneous speech was also assessed. In addition procedural errors in the parents' use of time delay were calculated. Results indicated that all children increased their daily spontaneous speech and generalized their speech to other locations and persons.     

Relationship maintenance strategies of rotational workers and their partners

Although individuals who reside permanently in one location and work temporarily in another (i.e., rotational workers) represent a sizeable segment of the population, they are understudied in the empirical literature. Because rotational workers and their at-home partners have unique long-distance relationships due to frequent separations and reunions, they and their relationships should be examined. The primary aim of this study was to identify key factors associated with maintenance of romantic relationships between rotational workers and their at-home partners. Participants (N = 289) were rotational workers (n = 129) and at-home partners of workers (n = 160) who completed online surveys on individual, dyadic, and extra-dyadic relationship maintenance behaviors and relationship characteristics over the course of two working-reunion (roster) phases. Results indicated individual, dyadic, and extra-dyadic behaviors positively predicted perceived relationship quality among partners and workers. Among partners, generosity positively predicted relationship quality at the first reunion and second departure phases. All other individual, dyadic, and extra-dyadic relationship maintenance behaviors predicted relationship quality, regardless of the roster phase. Overall, results suggest the importance of relationship maintenance education for individuals in rotational romantic relationships.