Dehydroepiandrosterone Heightens Aggression and Increases Androgen Receptor and Aromatase mRNA Expression in the Brain of a Male Songbird.

Dehydroepiandrosterone (DHEA) is a testosterone/oestrogen precursor and known modulator of vertebrate aggression. Male song sparrows (Melospiza melodia morphna) show high aggression during breeding and nonbreeding life-history stages when circulating DHEA levels are high, and low aggression during molt when DHEA levels are low. We previously showed that androgen receptor and aromatase mRNA expression are higher during breeding and/or nonbreeding in brain regions associated with reproductive and aggressive behaviour, although the potential role of DHEA in mediating these seasonal changes remained unclear. In the present study, nonbreeding male song sparrows were captured and held in the laboratory under short days (8 : 16 h light/dark cycle) and implanted with s.c. DHEA-filled or empty (control) implants for 14 days. DHEA implants increased aggression in a laboratory-based simulated territorial intrusion. Brains of DHEA-implanted birds showed higher aromatase mRNA expression in the preoptic area (POA) and higher androgen receptor mRNA expression in the periventricular nucleus of the medial striatum (pvMSt) and ventromedial nucleus of the hypothalamus. The DHEA-induced increases in aromatase expression in the POA and androgen receptor expression in the pvMSt are consistent with previously reported seasonal increases in these markers associated with naturally elevated DHEA levels. This suggests that DHEA facilitates seasonal increases in aggression in nonbreeding male song sparrows by up-regulating steroid signalling/synthesis machinery in a brain region-specific fashion.

Stimulus characteristics within directives: effects on accuracy of task completion.

Three experiments were conducted in an outpatient setting with young children who had been referred for treatment of noncompliant behavior and who had coexisting receptive language or receptive vocabulary difficulties. Experiment 1 studied differential responding of the participants to a brief hierarchical directive analysis (least-to-most complex stimulus prompts) to identify directives that functioned as discriminative stimuli for accurate responding. Experiment 1 identified distinct patterns of accurate responding relative to manipulation of directive stimulus characteristics. Experiment 2 demonstrated that directives identified as effective or ineffective in obtaining stimulus control of accurate responding during Experiment 1 continued to control accurate responding across play activities and academic tasks. Experiment 3 probed effects of the interaction between the type of directive (effective vs. ineffective) and the reinforcement contingency (differential reinforcement for attempts vs. differential reinforcement for accurate responses) on accurate task completion and disruptive behavior. Results suggested that behavioral escalation from inaccurate responding to disruptive behavior occurred only when ineffective directives were combined with differential reinforcement for accurate task completion. The overall results are discussed in terms of developing a methodology for identifying stimulus characteristics of directives that affect accurate responding.

Analysis of response class hierarchies with attention-maintained problem behaviors.

We replicated a method for clarifying inconclusive functional analysis outcomes via an extinction analysis of separate topographies of problem behavior with 2 participants. Results suggested that both mild and severe problem behaviors belonged to the same response class. An analysis of response latency was consistent with a response class hierarchy hypothesis, indicating that mild problem behavior nearly always occurred prior to severe topographies of problem behavior.

Response efficiency during functional communication training: effects of effort on response allocation.

An analogue functional analysis revealed that the problem behavior of a young child with developmental delays was maintained by positive reinforcement. A concurrent-schedule procedure was then used to vary the amount of effort required to emit mands. Results suggested that response effort can be an important variable when developing effective functional communication training programs.

Effects of escape to alone versus escape to enriched environments on adaptive and aberrant behavior.

Escape-maintained aberrant behavior may be influenced by two outcomes: (a) a break from the activity and (b) subsequent access to preferred activities. To assess this hypothesis, a treatment was developed that analyzed response allocation across two break options: break alone and break with access to preferred social activities. The break with preferred activities decreased aberrant behavior and increased appropriate behavior.

Evaluating the effects of functional communication training in the presence and absence of establishing operations.

We conducted functional analyses of aberrant behavior with 4 children with developmental disabilities. We then implemented functional communication training (FCT) by using different mands across two contexts, one in which the establishing operation (EO) that was relevant to the function of aberrant behavior was present and one in which the EO that was relevant to the function of aberrant behavior was absent. The mand used in the EO-present context served the same function as aberrant behavior, and the mand used in the EO-absent context served a different function than the one identified via the functional analysis. In addition, a free-play (control) condition was conducted for all children. Increases in relevant manding were observed in the EO-present context for 3 of the 4 participants. Decreases in aberrant behavior were achieved by the end of the treatment analysis for all 4 participants. Irrelevant mands were rarely observed in the EO-absent context for 3 of the 4 participants. Evaluating the effectiveness of FCT across different contexts allowed a further analysis of manding when the establishing operations were present or absent. The contributions of this study to the understanding of functional equivalence are also discussed.

The effects of presession exposure to attention on the results of assessments of attention as a reinforcer.

The effects of presession exposure to attention on responding during subsequent assessments of attention as a reinforcer were evaluated across three behavioral assessments. In Experiment 1, a contingent attention assessment condition was preceded by either a noncontingent attention condition (free play) or a contingent escape condition. In Experiment 2, a diverted attention with extinction condition was preceded by either an alone or a free-play condition. In Experiment 3, a two-choice preference assessment was preceded by either 10 min of free play or 10 min of playing alone. In each experiment, the participant responded differentially within the test condition according to the presence or absence of dense schedules of attention immediately prior to that condition. The results of this study show that events occurring immediately prior to an assessment condition can influence behavior within the assessment.

Further analysis of problem behavior in response class hierarchies.

A functional analysis identified the reinforcers for 3 participants' problem behavior, but only relatively mild problem behaviors (e.g., screaming, disruption) were observed when all topographies produced tested consequences. We then conducted an extinction analysis in which specific topographies produced a reinforcer while all other topographies were on extinction. The extinction analysis confirmed that the same reinforcer identified in the initial functional analysis maintained more severe topographies of problem behavior (e.g., aggression). In addition, results of the extinction analysis indicated that 2 of the participants displayed patterns of responding consistent with a response class hierarchy hypothesis, in which less severe problem behavior frequently occurred prior to more severe topographies. The 3rd participant displayed a response pattern indicative of differential reinforcement effects.

Combining descriptive and experimental analyses of young children with behavior problems in preschool settings.

This investigation shows the merits of preceding experimental analyses with descriptive analyses of functional variables with preschool children who engage in problematic behavior. A two-phase descriptive analysis was conducted in daycare settings with three children. In Phase 1, the authors assessed the relation between child behavior and structural events. During Phase 2, the same behavior was replotted by functional variables. The results showed that when the descriptive data were plotted via functional variables, specific hypotheses could be generated regarding the variables controlling appropriate behavior. This procedure permitted the subsequent use of very brief experimental analyses to further identify functional relations. The use of descriptive analyses of functional rather than structural variables may be an important component in the assessment of problem behavior in community settings.

An analysis of choice making in the assessment of young children with severe behavior problems.

We examined how positive and negative reinforcement influenced time allocation, occurrence of problem behavior, and completion of parent instructions during a concurrent choice assessment with 2 preschool-aged children who displayed severe problem behavior in their homes. The children were given a series of concurrent choice options that varied availability of parent attention, access to preferred toys, and presentation of parent instructions. The results showed that both children consistently allocated their time to choice areas that included parent attention when no instructions were presented. When parent attention choice areas included the presentation of instructions, the children displayed differential patterns of behavior that appeared to be influenced by the presence or absence of preferred toys. The results extended previous applications of reinforcer assessment procedures by analyzing the relative influence of both positive and negative reinforcement within a concurrent-operants paradigm.

Use of a concurrent operants paradigm to evaluate positive reinforcers during treatment of food refusal.

The authors evaluated the responsiveness of 4 preschool-aged children to positive reinforcers within a concurrent operants paradigm during mealtimes. The children were presented with two identical, concurrently available sets of food. Each set differed in quantity and quality of positive reinforcement paired with acceptance of each bite of food or in the number of bites of food required to obtain positive reinforcement. Experiment 1 evaluated 1 child's responsiveness to positive reinforcement while permitting escape from bite offers. Experiment 2 evaluated 2 children's responsiveness to positive reinforcement when escape extinction occurred. Results from these experiments suggested that the children were responsive to positive reinforcers and chose more often the bites paired with the greater quantity and/or quality of reinforcement. Experiment 3 evaluated 1 child's responsiveness to positive reinforcement both without and with escape extinction. Results suggested that positive reinforcement affected choice behavior and that escape extinction affected amount of food consumed.

Evaluation of antecedent stimulus parameters for the treatment of escape-maintained aberrant behavior.

We evaluated a methodology for identifying the range of stimulus features of antecedent stimuli associated with aberrant behavior in demand contexts in natural settings. For each participant, an experimental analysis of antecedents (Phase 1) was conducted to confirm the hypothesis that task instructions occasioned increases in aberrant behavior. During Phase 2, specific stimulus features associated with the presentation of task instructions were assessed by evaluating the child's behavior across two distinct settings, therapists, and types of tasks in a sequential fashion. Aberrant behavior occurred immediately across settings and therapists, presumably because the presence of a discriminative stimulus for escape-maintained behavior (the delivery of a task instruction) occasioned aberrant behavior. However, aberrant behavior decreased initially across tasks, suggesting that familiarity with the task might be a variable. During Phase 3, an experimental (functional) analysis of consequences was conducted with 2 participants to verify that aberrant behavior was maintained by negative reinforcement. During Phase 4, a treatment package that interspersed play with task instructions was conducted to disrupt the ongoing occurrence of aberrant behavior. Immediate and durable treatment effects occurred for 2 of the 3 participants.

Teaching multiplication facts to students with learning disabilities.

Multiple baseline designs were used to examine the effects of an instructional package on accuracy of performance in solving multiplication facts by 3 students with learning disabilities. The instructional package included the following components: (a) a modified instructional sequence in which multiplication facts were grouped into the zeros, ones, doubles, fives, and nines categories, and those remaining; (b) identification of the category in which each fact belonged; (c) mnemonic strategies associated with solving facts in each category; and (d) steps to be completed for solving facts in each category. Results indicated that the instructional package produced substantial and immediate effects. After receiving instruction, a participant's accuracy was often 100%, and this was maintained throughout the evaluation even as other strategies were introduced. Comparable results occurred across students, demonstrating replication of the effects of the instructional package.

Functional analysis and extinction of different behavior problems exhibited by the same individual.

Specific extinction procedures were matched to the function of two target behaviors displayed by the same individual, with results indicating that the matched extinction procedure suppressed the behavior for which it was designed. One of the target behaviors was exposed to an irrelevant extinction procedure, which produced no beneficial effects. These results support previous research indicating the need to match extinction procedures to the function of problem behavior.

Evaluation and long-term treatment of aberrant behavior displayed by young children with disabilities.

We trained parents to conduct functional analyses and functional communication treatment for 28 young children with developmental disabilities who displayed aberrant behavior. Of this sample, 22 parents conducted treatment for at least 3 months and 11 for 1 year. We conducted single-case analyses of the results of assessment and treatment. The functional analysis identified social functions (positive and negative reinforcement) for 86% (24 of 28) of the children. Treatment resulted in a pre/post decrease in aberrant behavior averaging 87% across the range of children, with the greatest decrease occurring at 3 months. Appropriate social responding increased, on average, by 69% across the range of children. Decreases in aberrant behavior were demonstrated in all children, and all except one child displayed increased social behavior during treatment. On a measure of parent-rated treatment acceptability, ranging from 1 (not at all acceptable) to 7 (very acceptable), the average overall acceptability was 6.35.

Increasing compliance with medical procedures: application of the high-probability request procedure to a toddler.

The effects of high-probability (high-p) requests on compliance with low-probability (low-p) responses have received increased attention from applied investigators. This study examined the effects of a high-p procedure on a toddler's compliance with medical procedures. Compliance to low-p requests occurred more frequently following compliance to high-p requests, suggesting that this procedure may be useful across different topographies of compliance.

The long-term effects of functional communication training in home settings.

A four-phase study was conducted in the homes of 4 young children who displayed aberrant behavior. Phases 1 and 2 consisted of a series of descriptive and experimental analyses to identify the environmental antecedents and consequences that controlled aberrant behavior. Phases 3 and 4 evaluated the short- and long-term effects of treatment on aberrant behavior, target mands, and collateral (social and toy play) behaviors. The effects of treatment were monitored for up to 27 months to assess long-term suppression of aberrant behavior. The assessment results successfully identified environmental events that occasioned and maintained aberrant behavior for all children. The short-term treatment resulted in immediate decreases in aberrant behavior for 3 of 4 children. Long-term treatment was successful for all children and was correlated with substantial response generalization. These results are interpreted in relation to functional equivalence, pivotal responding, and response generalization.

Toward the development of structured criteria for interpretation of functional analysis data.

Using functional analysis results to prescribe treatments is the preferred method for developing behavioral interventions. Little is known, however, about the reliability and validity of visual inspection for the interpretation of functional analysis data. The purpose of this investigation was to develop a set of structured criteria for visual inspection of multielement functional analyses that, when applied correctly, would increase interrater agreement and agreement with interpretations reached by expert consensus. In Study 1, 3 predoctoral interns interpreted functional analysis graphs, and interrater agreement was low (M = .46). In Study 2, 64 functional analysis graphs were interpreted by a panel of experts, and then a set of structured criteria were developed that yielded interpretive results similar to those of the panel (exact agreement = .94). In Study 3, the 3 predoctoral interns from Study 1 were trained to use the structured criteria, and the mean interrater agreement coefficient increased to .81. The results suggest that (a) the interpretation of functional analysis data may be less reliable than is generally assumed, (b) decision-making rules used by experts in the interpretation of functional analysis data can be operationalized, and (c) individuals can be trained to apply these rules accurately to increase interrater agreement. Potential uses of the criteria are discussed.

Irreversible inhibition of high-affinity [3H]kainate binding by a novel photoactivatable analogue: (2'S,3'S,4'R)-2'-carboxy-4'-(2-diazo-1-oxo-3, 3,3-trifluoropropyl)-3'-pyrrolidinyl acetate.

A photolabile trifluoromethyldiazoketone derivative of kainate (KA), (2'S,3'S,4'R)-2'-carboxy-4'-(2-diazo-1-oxo-3, 3,3-trifluoropropyl)-3'-pyrrolidinyl acetate (DZKA), was synthesized and evaluated as an irreversible inhibitor of the high-affinity KA site on rat forebrain synaptic plasma membranes (SPMs). In the absence of UV irradiation, DZKA preferentially blocked [3H]KA binding with an IC50 of 0.63 microM, a concentration that produced little or no inhibition at AMPA or NMDA sites. At 100 microM, however, DZKA inhibited [3H]AMPA and L-[3H]glutamate binding by approximately 50%. When examined electrophysiologically in HEK293 cells expressing human KA (GluR6) or AMPA (GluR1) subtypes, DZKA acted preferentially at KA receptors as a weak agonist. DZKA also exhibited little or no excitotoxic activity in mixed rat cortical cultures. Irreversible inhibition was assessed by pretreating SPMs with DZKA (50 microM) in the presence of UV irradiation, removing unbound DZKA, and then assaying the reisolated SPMs for radioligand binding. This protocol produced a selective and irreversible loss of approximately 50% of the [3H]KA sites. The binding was recoverable in SPMs pretreated with DZKA or UV alone. Coincubation with L-glutamate prevented the loss in [3H]KA binding, suggesting that the inactivation occurred at or near the ligand binding site. These results are consistent with the action of DZKA as a photoaffinity ligand for the KA site and identify the analogue as a valuable probe for future investigations of receptor structure and function.