The effects of delayed reinforcement on free-operant responding

In previous studies of delayed reinforcement, response rate has been found to vary inversely with the response-reinforcer interval. However, in all of these studies the independent variable, response-reinforcer time, was confounded with the number of reinforcers presented in a fixed period of time (reinforcer frequency). In the present study, the frequency of available reinforcers was held constant, while temporal separation between response and reinforcer was independently manipulated. A repeating time cycle, T, was divided into two alternating time periods, t^D and t^Δ. The first response in t^D was reinforced at the end of the prevailing T cycle and extinction prevailed in t^Δ. Two placements for t^D were defined, an early t^D placement in which t^D precedes t^Δ and a late t^D placement in which t^D follows t^Δ. The duration of the early and late t^D was systematically decreased from 30 seconds (i.e., t^D = T) to 0.1 second. Manipulation of t^D placement and duration controlled the temporal separation between response and reinforcement, but it did not affect the frequency of programmed reinforcers, which was 1/T. The results show that early and late t^D placements of equal duration have similar overall effects upon response rate, reinforcer frequency, responses per reinforcer, and obtained response-reinforcer temporal separation. A stepwise regression analysis using log response rate as the dependent variable showed that the obtained delay was a significant first-step variable for six of eight subjects, with obtained reinforcer frequency significant for the remaining two subjects.     

Mentoring: Some ethical considerations

To counter confusion about the term ‘mentor’, and address concerns about the scarcity of mentoring, I argue for an “honorific” definition, according to which a mentor is virtuous like a saint or hero. Given the unbounded commitment of mentors, mentoring relationships must be voluntary. In contrast, the role of advisor can be specified, mandated, and monitored. I argue that departments and research groups have a moral responsibility to devise a system of roles and structures to meet graduate students’ and postdoctoral fellows’ needs for information and advice. An earlier version of this paper was presented at a conference sponsored by the National Science Foundation on Mentoring and Research Values: Students as Vital Human Resources, Chicago, March 1995.     

Commentary: How Individual and Profession-level Factors Influence Discussion of Disability in Prenatal Genetic Counseling

Hodgson and Weil (Journal of Genetic Counseling, 2011) reports on two interactive workshops in which genetic counselors identified a broad set of counseling issues that may be impediments to promoting an adequate discussion of disability in prenatal genetic counseling. The present commentary discusses two factors that we infer underlie these counseling issues. First, countertransference concerning disability, which is normal and expected, may influence genetic counselors’ decisions about raising and exploring the complex topic of disability in prenatal genetic counseling. Second, the limited involvement of the profession of genetic counseling in the complex social and ethical issues of disability provide little guidance to the individual genetic counselor with respect to discussing disability in prenatal diagnosis counseling. We suggest both factors must be acknowledged and addressed in order to adequately implement the recommendations presented in Hodgson and Weil (Journal of Genetic Counseling, 2011) as well as other efforts to increase discussion of disability in prenatal diagnosis counseling in the service of informed decision making.     

The development of metacognitive ability in adolescence

Introspection, or metacognition, is the capacity to reflect on our own thoughts and behaviours. Here, we investigated how one specific metacognitive ability (the relationship between task performance and confidence) develops in adolescence, a period of life associated with the emergence of self-concept and enhanced self-awareness. We employed a task that dissociates objective performance on a visual task from metacognitive ability in a group of 56 participants aged between 11 and 41 years. Metacognitive ability improved significantly with age during adolescence, was highest in late adolescence and plateaued going into adulthood. Our results suggest that awareness of one’s own perceptual decisions shows a prolonged developmental trajectory during adolescence.     

The development and analysis of tutorial dialogues in AutoTutor Lite

The goal of intelligent tutoring systems (ITS) that interact in natural language is to emulate the benefits that a well-trained human tutor provides to students, by interpreting student answers and appropriately responding in order to encourage elaboration. BRCA Gist is an ITS developed using AutoTutor Lite, a Web-based version of AutoTutor. Fuzzy-trace theory theoretically motivated the development of BRCA Gist, which engages people in tutorial dialogues to teach them about genetic breast cancer risk. We describe an empirical method to create tutorial dialogues and fine-tune the calibration of BRCA Gist’s semantic processing engine without a team of computer scientists. We created five interactive dialogues centered on pedagogic questions such as “What should someone do if she receives a positive result for genetic risk of breast cancer?” This method involved an iterative refinement process of repeated testing with different texts and successively making adjustments to the tutor’s expectations and settings in order to improve performance. The goal of this method was to enable BRCA Gist to interpret and respond to answers in a manner that best facilitated learning. We developed a method to analyze the efficacy of the tutor’s dialogues. We found that BRCA Gist’s assessment of participants’ answers was highly correlated with the quality of the answers found by trained human judges using a reliable rubric. The dialogue quality between users and BRCA Gist predicted performance on a breast cancer risk knowledge test completed after exposure to the tutor. The appropriateness of BRCA Gist’s feedback also predicted the quality of answers and breast cancer risk knowledge test scores.     

Understanding Strengths in Relation to Complex Trauma and Mental Health Symptoms within Child Welfare

Strengths can have a potent effect in mitigating the impact of trauma on mental health needs and functioning. Yet, evidence is limited on the role that strengths may have in ameliorating trauma-related or mental health symptoms over time. Providing a comprehensive assessment that includes strengths, as well as needs, is an important step in making appropriate service recommendations for youth in child welfare. This study assessed 7,483 children and adolescents entering an intensive stabilization program through the Illinois child welfare system. The interaction of individual, child strengths in relation to complex trauma exposure, traumatic stress symptoms, risk behaviors, and other mental health needs were examined. Results indicated strengths are relatively stable over time and inversely associated with several negative outcomes, including risk behaviors (?.32, p?<?.001), emotional/ behavioral needs (?.33, p?<?.001) and overall functioning (?.47, p?<?.001). Traumatic stress symptoms were also related to increases in these negative outcomes. Overall, strengths had a buffering effect on traumatic stress symptoms and outcomes over time. The role of strengths in relation to traumatic stress symptoms, however, was less consistent. Youth with histories of complex trauma exposure had significantly fewer useable strengths than youth without this exposure. However, strengths improved for both youth with and without complex trauma exposure over the course of stabilization services. These findings suggest that early identification and development of child strengths can mitigate risk-taking behaviors, mental health, and functional difficulties among youth in the child welfare system. Implications for more targeted trauma-informed and strengths-based assessment, and treatment/service planning are discussed.     

Evaluating the effects of reactivity to supervisor presence on staff response to tactile prompts and self‐monitoring in a group home setting

Because staff management research in group home settings typically involves direct observation of staff performance, reactivity to being observed is a potential limitation in these studies. The current study evaluated the use of a tactile prompt, self‐monitoring, and feedback to increase positive interaction in a group home setting. Reactivity was assessed by having a confederate observe staff positive interaction when the supervisor was present and when the supervisor was absent. The effect of supervisor presence was evaluated using an alternating treatment within a multiple baseline across participants' research design. Results showed that two of four participants increased positive interactions only when a supervisor was present and the two other participants increased positive interaction only when a supervisor was present and provided feedback. Copyright © 2010 John Wiley & Sons, Ltd.     

Sex differences in competition—cooperation behavior of children at two age levels

Competitive or cooperative behaviors of children were observed in two experiments. In Experiment 1, 7- to 9-year-old boys and girls played a board game with same- or opposite-sex partners under instructions which stressed either group or individual performance. Girls' behavior varied as a function of both instructions and partner sex. Girls playing the game with boys showed more highly competitive behavior than did girls who played the game with girls. Boys were highly competitive under all conditions. In Experiment 2, preschool children were observed in a similar game. For both sexes, children who played the game with opposite-sex partners were more competitive and obtained fewer rewards than those who interacted with same-sex partners. Thus, with development, boys show a change from selective competitiveness to a very general tendency to compete, while girls show a consistent tendency to vary their game behavior according to situational cues such as those provided by instructions or the sex of a game partner.A report of the first experiment was made at the Third Biennial Southeastern Conference of the Society for Research in Child Development, Chapel Hill, March 1974. The authors would like to thank the personnel of St. Francis Cabrini School and the Children's House Montessori School of New Orleans, Louisiana, for their cooperation in providing research participants.