Pigeons prefer to invest early for future reinforcers

Five pigeons were trained in a series of conditions in which food was delivered after 25 responses, but only when a different (Investing) response had been made before the 25 responses had been completed. If an Investing response was not made, the 25 responses ended in blackout. In various conditions, effective Investing responses either had to be made before the first of the 25 responses, or anywhere within the 25 responses; and effective Investing responses either resulted in a stimulus change or did not. Pigeons Invested even when the consequences were temporally and spatially distant, but Investing was most likely when it produced an immediate stimulus change. When given the choice, pigeons preferred to make Investing responses at the beginning of a trial. These findings again demonstrate that behavior may be maintained by events that are separated in time and space from the present.     

Effects of multiple versus chained schedules on stereotypy and item engagement

We evaluated rates of automatically reinforced stereotypy and item engagement for 2 children with autism under multiple and chained schedules in a multielement design. Each schedule included components during which stereotypy was blocked (S–) or allowed (S+), and we used colored cards as schedule‐correlated stimuli. We report rates of stereotypy and item engagement during S– and S+ components, as well as the percentage of component time that elapsed before the first instances of stereotypy and item engagement. We observed less stereotypy and more consistent item engagement during chained‐schedule sessions, and stimulus control of stereotypy and item engagement was established with the chained schedule. A subsequent concurrent‐chains analysis revealed participant preference for the chained schedule. These results highlight the importance of contingent access to stereotypy when therapists attempt to gain stimulus control of stereotypy and increase functional item engagement.     

The selective action of Cfunc control

According to relational frame theory Cfunc stimuli select which stimulus properties are transformed via derived stimulus relations. To date there has been no demonstration of the selective action of Cfunc control. We provide an analysis of the requirements for such a demonstration, and describe the results from four experiments employing a paradigm consistent with these requirements. We employed a paradigm based on virtual car races. The paradigm had two components: i) a sample racecar screen which showed the performance of a sample racecar, and used experimentally engineered symbols to communicate how the performance of each real racecar would compare with that of the sample racecar, and ii) a car race screen showing other racecars race. Two symbols were established as Crels for the relations of same and different, and two symbols were established as Cfuncs for the functional properties of speed and direction. The results from these experiments demonstrate Cfunc stimuli can select which functions transform via derived stimulus relations, a central component of relational frame theory. The study has implications for the study of relational responding in complex settings and for applied work aimed at refining repertoires of relational responding.     

Access to Assistive Technology,Systems Thinking,and Market Shaping: A Response to Durocher et al.

Fairness of access to assistive technology is important for its allocation on an equitable basis and for broader social justice and rights issues. Although the use of Daniels’s notion of “justice as fair opportunity” is helpful to the context of assistive technology, other aspects of Daniels’s broader conceptualisation of “just health” are not appropriate in this context. It is argued that fairness of access to assistive technology is crucial for the equitable attainment of the sustainable development goals; however, such access will be achieved only by the sector developing a much stronger systems thinking and market shaping perspective.     

Transfer of conditioned fear and avoidance: Concurrent measurement of arousal and operant responding

A reversal design was employed for the analysis of transfer of fear and avoidance through equivalence classes. Two 5-member equivalence classes (A1-B1-C1-D1-E1 and A2-B2-C2-D2-E2) were established. Then B1 and C1 were paired with shock (CS+) and served as S^Ds in avoidance training (B2 and C2 were trained as CS-/S^∆s for avoidance). Further avoidance training followed with D1 and E1 (as S^Ds) and D2 and E2 (as S^∆s), with the first presentation of each of these stimuli serving as the first transfer test. Afterwards, aversive conditioning contingencies were reversed: B2 and D2 were paired with shock and trained as S^Ds for avoidance, B1 and D1 were presented without shock (CS-/S^∆s). Transfer was tested again with C1, E1, C2 and E2. This reversal was implemented to allow for the within-subject replication of transfer effects upon changes in the function of only a subset of each class's elements. Avoidance (key presses) and conditioned fear (skin conductance and heart rate) were simultaneously measured. Results show a clear transfer effect for avoidance, with between- and within-subject replications. For physiological measures, transfer effects in the first test could only be imputed on the basis of group-based inferential statistical analysis. Evidence for between-subject replication was weaker, with only a limited proportion of participants meeting the individual criterion for transfer.     

Does upper-body elevation affect sleepiness and memories of hypnagogic images after short daytime naps?

The present study aimed to examine the effects of a somatosensory stimulus on sleepiness and memories of hypnagogic imagery during short daytime naps. Participants experienced two daytime nap conditions: (1) a somatosensory stimulus was created by raising the upper part of the bed 20 min after turning off the light and (2) a somatosensory stimulus was not created; the angle of the upper part of the bed remained flat. Approximately 20 min and 30 s after turning off the light, participants were awakened and questioned regarding their subjective sleepiness and the presence or absence of hypnagogic imagery. Results showed that subjective sleepiness following the nap was reduced only in the raised condition, and hypnagogic imagery in the raised condition was lower than that in the flat condition. These findings may provide insight on developing new techniques for improving subjective conditions after awakening.     

Faking resistance of a quasi-ipsative RIASEC occupational interest measure

Quasi-ipsative (QI) forced-choice response formats are often recommended over single-stimulus (SS) as a method to reduce applicant faking. Across three studies we developed and tested a QI version of the RIASEC occupational interests scale. The first study established acceptable reliability and validity of the QI version. The second and third studies tested the efficacy of the QI version for faking prevention in simulated job applicant scenarios. The results revealed that although the QI and SS formats were similarly fakable for the primary targeted interest, faking was limited for the secondary target on the QI version. Future research should identify the specific contexts in which QI prevents faking on various individual differences measures to allow for accurate recommendations in applied settings.     

Comparing stimulus preference and response force in a conjugate preparation

Researchers used a conjugate preparation to evaluate how response force changed based on participants' preferences for visual stimuli. First, researchers used a verbal preference assessment to evaluate each participant's preference for viewing for five object categories of visual stimuli; this process identified high preference (HP) stimuli and low preference stimuli for most participants. Thereafter, researchers exposed each participant to the five stimulus categories in a randomized order while using a force dynamometer to measure their response force to increase visual clarity of each stimulus. Results indicate the majority of participants' HP stimuli corresponded to the stimulus category for which they exerted the highest mean force. These preliminary findings suggest conjugate preparations involving response force may provide another option for measuring the relative value of some stimulus events.