The danger of conflating level-specific effects of control variables when primary interest lies in level-2 effects

In the multilevel modelling literature, methodologists widely acknowledge that a level-1 variable can have distinct within-cluster and between-cluster effects, and that failing to disaggregate these can yield a slope estimate that is an uninterpretable, conflated blend of the two. Methodologists have stated, however, that including conflated slopes of level-1 variables in a model is not problematic if substantive interest lies only in effects of level-2 predictors. Researchers commonly follow this advice and use methods that do not disaggregate effects of level-1 control variables (e.g., grand mean centering) when examining effects of level-2 predictors. The primary purpose of this paper is to show that this is a dangerous practice. When level-specific effects of level-1 variables differ, failing to disaggregate them can severely bias estimation of level-2 predictor slopes. We show mathematically why this is the case and highlight factors that can exacerbate such bias. We corroborate these findings with simulations and present an empirical example, showing how such distortions can severely alter substantive conclusions. We ultimately recommend that simply including the cluster mean of the level-1 variable as a control will alleviate the problem.     

Timing the “magical number seven”: Presentation rate and regularity affect verbal working memory performance

The informative value of time and temporal structure often remains neglected in cognitive assessments. However, next to information about stimulus identity we can exploit temporal ordering principles, such as regularity, periodicity, or grouping to generate predictions about the timing of future events. Such predictions may improve cognitive performance by optimising adaptation to dynamic stimuli. Here, we investigated the influence of temporal structure on verbal working memory by assessing immediate recall performance for aurally presented digit sequences (forward digit span) as a function of standard (1000 ms stimulus-onset-asynchronies, SOAs), short (700 ms), long (1300 ms) and mixed (700–1300 ms) stimulus timing during the presentation phase. Participant's digit spans were lower for short and mixed SOA presentation relative to standard SOAs. This confirms an impact of temporal structure on the classic “magical number seven,” suggesting that working memory performance can in part be regulated through the systematic application of temporal ordering principles.     

Teaching caregivers to implement mand training using speech generating devices

Individuals with developmental disabilities often do not develop vocal repertoires, thus requiring the use of augmentative devices. Teaching caregivers to conduct communication training with their children may be one way to foster communication with their device in the natural environment. This study replicates Rosales, Stone and Rehfeldt (2009), but using an augmentative device. Behavioral skills training was used to teach caregivers to implement mand training procedures. Caregivers quickly learned to implement mand training with their children and independent mands increased from pretraining to posttraining observations for 2 out of 3 children.     

A brief review of technology-based antecedent training procedures

This brief review summarizes recent research on technology-based antecedent staff training procedures, highlights key methodological components, and concludes with potential directions for future research.     

Back to sleep: Teaching adults to arrange safe infant sleep environments

There are over 3,000 sleep related infant deaths each year in the United States. Attempts to teach medical personnel and parents safe infant sleep practices in the infant sleep training literature have demonstrated mixed results. Thus, strategies to teach arrangements of safe infant sleep environments warrant further investigation. Behavioral skills training (BST) is an evidence-based teaching strategy shown to successfully teach various safety skills to children and adults. The current study evaluated the effectiveness of behavioral skills training to teach safe infant sleep practices to typically developing adults. Specifically, differential responding was assessed across multiple environmental arrangements typical of contexts parents may be exposed to when putting an infant to sleep. BST significantly improved appropriate arrangement of a safe sleep environment for infants for all 8 participants.     

A comparison of isolated and synthesized contingencies in functional analyses

Recently, researchers have compared the utility of isolated versus synthesized contingencies in functional analysis (FA) methodology (e.g., Fisher et al., 2016; Slaton et al., 2017). A limitation of these studies is that there were other differences across FA methodologies (e.g., design, contingency) that did not allow for isolation of the influence of isolated versus synthesized contingencies. Therefore, the current study compared outcomes of FAs that involved isolated versus synthesized contingencies for problem behavior of 5 children while controlling for these other differences across FAs (Experiment 1). Next, the current study compared the effects of interventions based on the functions identified in the isolated and synthesized contingencies for each participant (Experiment 2). Results indicated isolated contingency FAs produced differentiated responding for 1 or both functions for all 5 participants, and there were little to no differences between treatments informed by isolated and synthesized contingency FAs.     

Providing noncontingent,alternative, functional reinforcers during delays following functional communication training

Functional Communication Training (FCT) involves arranging extinction for problem behavior and reinforcement for a more desirable, functionally equivalent, communicative response (FCR). Although effective under ideal arrangements, the introduction of delays to reinforcement following the FCR can result in increased problem behavior. Austin and Tiger (2015) showed that for individuals whose problem behavior was sensitive to multiple sources of reinforcement, providing access to alternative, functional reinforcers during delays mitigated this increase in problem behavior during delay fading. The current study replicated the procedures of Austin and Tiger with 2 individuals displaying multiply controlled problem behavior. Providing alternative functional reinforcers reduced problem behavior during 10-min delays for both participants without requiring delay fading.