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This review of research on behavioral discrimination of nicotine and how it informs public health policy for reducing risk of tobacco dependence is adapted from Kenneth A. Perkins's American Psychological Association Division 28 (Psychopharmacology and Substance Abuse) 2020 Med Associates Brady/Schuster Award Lecture. The author's initial programmatic clinical research on nicotine is introduced, especially efforts to develop and validate a novel method of acute nicotine dosing. After the public health rationale for characterizing the discriminative stimulus effects of nicotine in humans are described, details from two separate programs of research on nicotine discrimination in humans are presented. The first, conducted with nicotine dosing by nasal spray, documented that humans could discriminate nicotine administered rapidly, examined nicotine's neuropharmacological specificity, identified discrimination threshold dose in smokers and nonsmokers, and explored other conditions that might alter ability to discriminate its effects. The second, more recent program focused on threshold doses for discrimination of nicotine by cigarette smoking, a program that was very difficult to do until the past decade, and how nicotine's self-reported "reward" and preference via choice behavior relate to its discriminability. Differences due to menthol and degree of tobacco dependence were also examined. For each of these two programs, the main findings of selected studies are noted, followed by very recent work on nicotine discrimination and choice that informs Food and Drug Administration's efforts to formulate public policy to improve health and reduce the nearly half million American deaths per year due to persistent tobacco use. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

STUDY OBJECTIVES: Empirical evidence linking individual sleep hygiene practices to subsequent sleep parameters is limited, particularly at the daily level. This study compared the strength of daily, within-person associations between these modifiable sleep behaviors and nighttime sleep in young adult drinkers with insomnia. METHODS: Young adults (ages 18–30 years; n = 56) who met diagnostic criteria for insomnia and reported past-month binge drinking wore wrist actigraphy and completed online sleep diaries for 8.5 days (standard deviation = 2.3; 477 reports). Diaries assessed engagement in 11 sleep hygiene recommendations. Multilevel models tested daily associations between sleep behaviors and 3 outcomes: sleep quality, self-reported sleep efficiency, and actigraphy-measured sleep efficiency. RESULTS: Participants self-reported better sleep quality/efficiency on days that they slept in a comfortable environment, limited naps to 30 minutes, and maintained a consistent wake time. They self-reported worse sleep quality and efficiency on nights that they avoided alcohol use before bedtime. No sleep behaviors were significantly associated with actigraphy-measured sleep efficiency after correcting for inflation in type I error. CONCLUSIONS: The sleep hygiene recommendations most strongly associated with sleep at the daily level were consistent with stimulus control. Creating a comfortable sleep environment also emerged as an important correlate of daily sleep. Heavy drinkers with insomnia may perceive better sleep if they drink before bedtime; however, this finding may be unique to this population. CITATION: Miller MB, Curtis AF, Hall NA, et al. Daily associations between modifiable sleep behaviors and nighttime sleep among young adult drinkers with insomnia. J Clin Sleep Med. 2022;18(3):703–712.

AIMS To understand dual users' cigarette and e-cigarette use patterns including the contexts in which they vape vs smoke and to understand how environmental and internal contexts and smoking patterns differ between dual users and exclusive smokers. DESIGN Longitudinal observational trial. SETTING Research center in Wisconsin, USA. PARTICIPANTS Adult dual users (n=162) and adults who exclusively smoked (n=143), with no plans to quit smoking or vaping in the next 30 days MEASUREMENTS: Participants carried smartphones for 2 weeks at baseline to record each use event for the two products and report on the context of their product use. Percent of mornings where participants vaped first vs. smoked were used to compute e-cigarette dependence. FINDINGS Hierarchical linear regression models with random slopes and intercepts examined the within- and between-subject effects of context on the likelihood of vaping (vs. smoking); significant fixed effects were tested for moderation by e-cigarette dependence. Dual users reported significantly more puffs/cigarette (mean (M)=13.1, standard deviation (SD)=10.2) than puffs/vape event (M=11.7, SD=11.5; p=0.01). E-cigarette dependence moderated the influence of social cues (t-ratio=2.4, p=0.02) and smoking restrictions (t-ratio=3.1, p=0.003) on the likelihood of vaping versus smoking (odds ratio (OR)=2.30, p=0.02). Context was more related to which product was used in those of low versus higher e-cigarette dependence. Reports of strong cravings to smoke and positive expectancies for cigarettes were associated with reduced likelihood of vaping whereas strong cravings to vape and positive vaping expectancies were related to increased likelihood of vaping. CONCLUSIONS Among dual users of cigarettes and e-cigarettes with no motivation to quit, vaping appears to be related to internal cues and more highly linked with social contexts and smoking restrictions (i.e., under stronger external stimulus control) among those with low to moderate e-cigarette dependence compared with high e-cigarette dependence. These findings illustrate the importance of contextual factors in tobacco product use amongst dual users with the influence of context being reduced at high levels of e-cigarette dependence.

This study measured the responses of dogs to signals delivered via hand and voice signals. The study sought to determine whether dogs would display differential stimulus control when switching from a compound stimulus (auditory-visual) cue to presentation of only one of its elements. Twelve dogs performed a target behavior in response to a 2-element compound stimulus composed of a hand (visual modality) signal and a voice (auditory modality) signal. The mean percent correct responses to the visual element (M = 56.5, SD = 20.74) and the auditory element (M = 67.5, SD = 21.57) were both significantly lower than the 85% correct for the compound stimulus, P < 0.017. There was also evidence of a preference for one of the elements of the compound stimulus. The mean percent correct for the more favoured element (M = 77.25, SD = 12.53) was significantly higher than for the less favoured element (M = 46.75, SD = 17.2), P < 0.001. The identity of the favoured element was not consistent across the animals with 75% preferring the auditory element and 25% the visual element. This study contributes to an understanding of factors related to the stimulus control of learned behaviors. The differential control of behavior by alternative cues has implications for the training of assistance or service and other working animals with multiple cues. The results would strongly suggest that training with a compound stimulus is not appropriate if only elements of the compound stimulus are to be subsequently used.

Circuit manipulation has been a staple technique in neuroscience to identify how the brain functions to control complex behaviors. Chemogenetics, including designer receptors exclusively activated by designer drugs (DREADDs), have proven to be a powerful tool for the reversible modulation of discrete brain circuitry without the need for implantable devices, thereby making them especially useful in awake and unrestrained animals. This study used a DREADD approach to query the role of the nucleus accumbens (NAc) in mediating the interoceptive effects of 1.0 g/kg ethanol (i.g.) in rhesus monkeys (n = 7) using a drug discrimination procedure. After training, stereotaxic surgery was performed to introduce an AAV carrying the human muscarinic 4 receptor DREADD (hM4Di) bilaterally into the NAc. The hypothesis was that decreasing the output of the NAc by activation of hM4Di with the DREADD actuator, clozapine-n-oxide (CNO), would potentiate the discriminative stimulus effect of ethanol (i.e., a leftward shift the ethanol dose discrimination curve). The results showed individual variability shifts of the ethanol dose-response determination under DREADD activation. Characterization of the expression and function of hM4Di with MRI, immunohistochemical, and electrophysiological techniques found the selectivity of NAc transduction was proportional to behavioral effect. Specifically, the proportion of hM4Di expression restricted to the NAc was associated with the potency of the discriminative stimulus effects of ethanol. Together, these experiments highlight the NAc in mediating the interoceptive effects of ethanol, provide a framework for validation of chemogenetic tools in primates, and underscore the importance of robust within-subjects examination of DREADD expression for interpretation of behavioral findings.

Stimulus overselectivity remains an ill-defined concept within behavior analysis, because it can be difficult to distinguish truly restrictive stimulus control from random variation. Quantitative models of bias are useful, though perhaps limited in application. Over the last 50 years, research on stimulus overselectivity has developed a pattern of assessment and intervention repeatedly marred by methodological flaws. Here we argue that a molecular view of overselectivity, under which restricted stimulus control has heretofore been examined, is fundamentally insufficient for analyzing this phenomenon. Instead, we propose the use of the term “overselectivity” to define temporally extended patterns of restrictive stimulus control that have resulted in disproportionate populations of responding that cannot be attributed to chance alone, and highlight examples of overselectivity within the verbal behavior of children with autism spectrum disorder. Viewed as such, stimulus overselectivity lends itself to direct observation and measurement through the statistical analysis of single-subject data. In particular, we demonstrate the use of the Cochran Q test as a means of precisely quantifying stimulus overselectivity. We provide a tutorial on calculation, a model for interpretation, and a discussion of the implications for the use of Cochran’s Q by clinicians and researchers.

Despite the evidence that the muscarinic agonist arecoline is a drug of abuse throughout Southeast Asia, its stimulus characteristics have not been well studied. The goal of this work was to understand more about the mediation of discriminative stimulus effects of arecoline. Arecoline (1.0 mg/kg s.c.) was trained as a discriminative stimulus in a group of eight rats. Evaluation was made of the ability of various cholinergic agonists and antagonists to mimic or antagonize the discriminative stimulus effects of arecoline and to modify its rate-suppressing effects. A muscarinic antagonist, but neither of two nicotinic antagonists, were able to modify the discriminative stimulus effects of arecoline, suggesting a predominant muscarinic basis of arecoline’s discriminative stimulus effects in this assay. However, both nicotine itself, and two nicotine agonists with selective affinity for the α4β2* receptor (ispronicline and metanicotine) produced full arecoline-like discriminative stimulus effects in these rats. The discriminative stimulus effects of the selective nicotine agonists were blocked by both the general nicotine antagonist mecamylamine, and by the selective α4β2* antagonist, dihydro-beta-erythroidine (DHβE). Surprisingly, only DHβE antagonized the rate-suppressing effects of the selective nicotine agonists. These data indicate a selective α4β2* nicotine receptor component to the behavioral effects of arecoline. Although the nicotinic aspects of arecoline’s behavior effects could suggest that abuse of arecoline-containing material (e.g., betel nut chewing), is mediated through nicotinic rather than muscarinic actions, further research, specifically on the reinforcing effects of arecoline, is necessary before this conclusion can be supported.

Virtual reality (VR) is a new methodology for behavioral studies. In such studies, the millisecond accuracy and precision of stimulus presentation are critical for data replicability. Recently, Python, which is a widely used programming language for scientific research, has contributed to reliable accuracy and precision in experimental control. However, little is known about whether modern VR environments have millisecond accuracy and precision for stimulus presentation, since most standard methods in laboratory studies are not optimized for VR environments. The purpose of this study was to systematically evaluate the accuracy and precision of visual and auditory stimuli generated in modern VR head-mounted displays (HMDs) from HTC and Oculus using Python 2 and 3. We used the newest Python tools for VR and Black Box Toolkit to measure the actual time lag and jitter. The results showed that there was an 18-ms time lag for visual stimulus in both HMDs. For the auditory stimulus, the time lag varied between 40 and 60 ms, depending on the HMD. The jitters of those time lags were 1 ms for visual stimulus and 4 ms for auditory stimulus, which are sufficiently low for general experiments. These time lags were robustly equal, even when auditory and visual stimuli were presented simultaneously. Interestingly, all results were perfectly consistent in both Python 2 and 3 environments. Thus, the present study will help establish a more reliable stimulus control for psychological and neuroscientific research controlled by Python environments.

The one-shot pairing of a stimulus with a specific cognitive control process, such as task switching, can bind the two together in memory. The episodic control-binding hypothesis posits that the formation of temporary stimulus-control bindings, which are held in event-files supported by episodic memory, can guide the contextually appropriate application of cognitive control. Across two experiments, we sought to examine the role of task-focused attention in the encoding and implementation of stimulus-control bindings in episodic event-files. In Experiment 1, we obtained self-reports of mind wandering during encoding and implementation of stimulus-control bindings. Results indicated that, whereas mind wandering during the implementation of stimulus-control bindings does not decrease their efficacy, mind wandering during the encoding of these control-state associations interferes with their successful deployment at a later point. In Experiment 2, we complemented these results by using trial-by-trial pupillometry to measure attention, again demonstrating that attention levels at encoding predict the subsequent implementation of stimulus-control bindings better than attention levels at implementation. These results suggest that, although encoding stimulus-control bindings in episodic memory requires active attention and engagement, once encoded, these bindings are automatically deployed to guide behavior when the stimulus recurs. These findings expand our understanding of how cognitive control processes are integrated into episodic event files. Supplementary Information The online version contains supplementary material available at 10.3758/s13414-021-02343-9.

Precisely characterizing mental representations of visual experiences requires careful control of experimental stimuli. Recent work leveraging such stimulus control has led to important insights; however, these findings are constrained to simple visual properties like colour and line orientation. There remains a critical methodological barrier to characterizing perceptual and mnemonic representations of realistic visual experiences. Here, we introduce a novel method to systematically control visual properties of natural scene stimuli. Using generative adversarial networks (GAN), a state-of-art deep learning technique for creating highly realistic synthetic images, we generated scene wheels in which continuously changing visual properties smoothly transition between meaningful realistic scenes. To validate the efficacy of scene wheels, we conducted two behavioral experiments that assess perceptual and mnemonic representations attained from the scene wheels. In the perceptual validation experiment, we tested whether the continuous transition of scene images along the wheel is reflected in human perceptual similarity judgment. The perceived similarity of the scene images correspondingly decreased as distances between the images increase on the wheel. In the memory experiment, participants reconstructed to-be-remembered scenes from the scene wheels. Reconstruction errors for these scenes resemble error distributions observed in prior studies using simple stimulus properties. Importantly, perceptual similarity judgment and memory precision varied systematically with scene wheel radius. These findings suggest our novel approach offers a window into the mental representations of naturalistic visual experiences.

Hermann Ludwig Ferdinand von Helmholtz (1821-1894) began investigating vision at a time when its study was undergoing a revolution. Laboratory experiments were augmenting the long history of naturalistic observations. Instruments of stimulus control enabled the manipulation of time and space in ways that had not been possible previously, and Helmholtz added to their tally. Vision was a central issue in his early years as an academic, and the bicentenary of his birth is here celebrated visually. Much of his research on vision was described in his Handbuch der physiologischen Optik, which was translated into English to mark the centenary of his birth. The history of his Handbuch is examined, together with illustrating highlights from it. Helmholtz's contributions to understanding the eye as an optical instrument, the sensations of vision, and perception were expressed in the three parts of the Handbuch, which became the three volumes of his Treatise on Physiological Optics.

Background Synthetic cathinones display overlapping behavioral effects with psychostimulants (e.g., methamphetamine [MA]) and/or entactogens (e.g., 3,4-methylenedioxymethaphetamine [MDMA])—presumably reflecting their dopaminergic and/or serotonergic activity. The discriminative stimulus effects of MDMA thought to be mediated by such activity have been well characterized in rodents but have not been fully examined in nonhuman primates. Methods The present studies were conducted to systematically evaluate the discriminative stimulus effects of 5 abused synthetic cathinones (methylenedioxypyrovalerone [MDPV], α-pyrrolidinovalerophenone [α-PVP], methcathinone [MCAT], mephedrone, and methylone) in adult male squirrel monkeys trained to distinguish intramuscular injections of MA (0.1 mg/kg; n = 4) or MDMA (0.6 mg/kg; n = 4) from vehicle. Results Each training drug produced dose-dependent effects and, at the highest dose, full substitution. MDMA produced predominantly vehicle-like responding in the MA-trained group, whereas the highest dose of MA (0.56 mg/kg) produced partial substitution (approximately 90% appropriate lever responding in one-half of the subjects) in the MDMA-trained group. MDPV, α-PVP, and MCAT produced full substitution in MA-trained subjects, but, at the same or higher doses, only substituted for MDMA in one-half of the subjects, consistent with primarily dopaminergically mediated interoceptive effects. In contrast, mephedrone and methylone fully substituted in MDMA-trained subjects but failed to fully substitute for the training drug in MA-trained subjects, suggesting a primary role for serotonergic actions in their interoceptive effects. Conclusions These findings suggest that differences in the interoceptive effects of synthetic cathinones in nonhuman primates reflect differing compositions of monoaminergic actions that also may mediate their subjective effects in humans.

This study aimed to assess whether applied behavior analysis (ABA) procedures such as feedback, goal setting and stimulus control, combined with acceptance and commitment training (ACTr) interventions implemented digitally improve levels of physical activity, consistency with self-care values and psychological flexibility during the COVID-19 pandemic. A nonconcurrent multiple baseline design across five participants was used in this study. Participants included five women with BMI's in the overweight or obese range. All participants were exposed to two intervention phases. In the first phase, feedback, goal setting and stimulus control procedures were implemented to improve physical activity. In the next phase, these procedures were combined with mindful walking exercises and values clarification exercises. In addition, psychological flexibility related to physical activity and values consistency were measured throughout the study. Results indicated that step count improved with the implementation of ABA + ACTr across all participants. Furthermore, psychological flexibility and self-care value scores improved after the intervention and maintained at 1-week follow-up. Lastly, the impact of physical activity during COVID-19, effectiveness and efficiency of ABA + ACT interventions are discussed.

Newly emerging synthetic cannabinoid compounds continue to be found in the designer drug market. They are often targeted as a “legal high” alternative to traditional cannabinoids via “darknet” markets and their increased potency and efficacy are becoming a growing concern internationally. The purpose of this study was to determine whether 4-CN-CUMYL-BUTINACA, 4F-MDMB-BINACA, 5F-AEB, 5F-CUMYL-P7AICA and EMB-FUBINACA exhibited similar behavioral effects as Δ(9)-tetrahydrocannabinol (Δ(9)-THC). Locomotor activity was assessed in an open-field assay using Swiss-Webster mice. Male Sprague-Dawley rats were trained to discriminate between IP injections of Δ(9)-THC (3 mg/kg) and vehicle. Following successful training, substitution tests for 4-CN-CUMYL-BUTINACA, 4F -MDMB-BINACA, 5F-AEB, 5F-CUMYL-P7AICA and EMB-FUBINACA were conducted. All of the test compounds decreased locomotor activity. 4-CN-CUMYL-BUTINACA (ED(50)= 0.26 mg/kg), 4F-MDMB-BINACA (ED(50)=0.019 mg/kg), 5F-CUMYL-P7AICA (ED(50)= 0.13 mg/kg) and EMB-FUBINACA (ED(50) = 0.13 mg/kg) each fully substituted for the discriminative stimulus effects of the training dose of Δ(9)-THC, whereas 5F-AEB produced only a maximum of 67% drug-appropriate responding at 0.5 mg/kg. Higher doses produced piloerection, exophthalmos and convulsions. 4-CN-CUMYL-BUTINACA, 4F-MDMB-BINACA, 5F-CUMYL-P7AICA and EMB-FUBINACA are likely to produce similar subjective effects in humans as those produced by abused synthetic cannabinoids, and may therefore share similar abuse liability. In contrast, 5F-AEB may have a reduced abuse liability given its weaker THC-like discriminative stimulus effects, but may be more dangerous due to the adverse effects observed at doses needed to produce discriminative stimulus effects.

Dois procedimentos têm sido propostos como alternativas para induzir repertórios não ensinados diretamente: 1) instrução com múltiplos exemplares (MEI); e 2) observação de pareamento de estímulos (SPOP). O MEI implica a rotação do ensino de diferentes respostas a um estímulo (ex. tato e resposta de ouvinte), o que favorece a aprendizagem incidental dessas respostas para novos estímulos a partir do ensino de apenas um dos tipos. No SPOP é exigida apenas a observação de estímulos apresentados contíguos, sem reforçamento diferencial para qualquer resposta. Os resultados de alguns estudos sugerem que uma maior frequência de pareamentos poderia levar a emergência de respostas de tato e ouvinte não ensinadas diretamente e que o pareamento de estímulos pode afetar o procedimento de MEI. O presente estudo avaliou o efeito de SPOP com uma frequência maior de pareamentos por tentativas sobre a emergência de respostas de tato e ouvinte em três crianças com Transtorno do Espectro Autista, e o efeito do SPOP no ensino dessas respostas por meio de MEI. Para dois participantes, o SPOP com mais pareamentos a cada tentativa favoreceu a emergência do repertório de ouvinte. Estes participantes somente aprenderam respostas de tato após o MEI. O SPOP teve um efeito facilitador no treino de MEI. Discute-se o papel do MEI e de treino de tato intensivo na emergência de repertórios de tato e ouvinte, assim como os tipos de controle de estímulo que o SPOP parece favorecer, e a possibilidade de investigar o SPOP em ambientes menos estruturados.

Transfer trials are a component of discrete-trial training in which the therapist re-presents the initial instruction following a prompted trial to provide an opportunity for the learner to answer independently. Transfer trials may expedite the transfer of stimulus control, are commonly used by practitioners and researchers, and are often recommended as best practice by applied behavior analysis organizations. However, there is little research comparing the efficiency and efficacy of transfer trials to more traditional teaching procedures. The current study evaluated and compared transfer trials to a nontransfer trial procedure for two-component tacting with three children diagnosed with an autism spectrum disorder. Results indicated both procedures were both effective and efficient for teaching two-component tacts for all learners, supporting the inclusion of transfer trials in discrete-trial training.

We examined emergent tact control following stimulus pairing, using 2 different stimulus presentation arrangements. In the word-first condition, presentation of the auditory stimulus preceded the visual stimulus, and in the image-first condition, the visual stimulus preceded the auditory stimulus. Eight children (2–5 years old) participated. In Experiment 1, 4 children were exposed to 3 sessions in each condition with a new set of stimuli in each session. In Experiment 2, 2 of the same children received repeated exposure to the same stimulus sets. Experiment 3, with new participants, was identical to Experiment 1, except visual and auditory stimuli overlapped during the presentation. Postsession probes documented emergent stimulus control over 1 or more vocal responses for 7 of the 8 participants. Participants were more likely to make echoic responses with the visual stimulus present in the word-first condition; however, emergent tact control was unaffected by the order of the stimulus presentation. Additional research is needed on stimulus-pairing procedures and on the role of echoic responding in emergent tact control.

Two experiments with rat subjects separated learning about the discriminative stimulus versus the operant response in the extinction of discriminated operant learning. Each was designed to separate 2 forms of error that could generate extinction learning from an error-correction perspective: Stimulus error, where the discriminative stimulus overpredicts the reinforcer in extinction, and response error, where the response is higher than what the current reinforcer supports. Stimulus error would cause correction of the Pavlovian stimulus-reinforcer association, whereas response error could cause correction of the instrumental response through adjustment of the response-reinforcer association or direct inhibition of the response. Previous research has supported a role for prediction error in instrumental extinction but has confounded these 2 potential sources of error. Using new variations of the concurrent excitor paradigm (Experiment 1) and the overexpectation paradigm (Experiment 2), the present experiments manipulated response error while controlling stimulus error. Both demonstrated that response error plays a role in instrumental extinction. When a discriminated operant response is not reinforced, response error correction may cause the animal to learn to suppress that specific response. (PsycInfo Database Record (c) 2020 APA, all rights reserved).