Assessment of operant learning and memory in mice born through ICSI.

STUDY QUESTION: Are there differences in operant learning and memory between mice born through ICSI and naturally conceived control (CTL) mice? SUMMARY ANSWER: ICSI females exhibited deficits in the acquisition reward learning relative to CTL females, and ICSI males exhibited deficiencies in discrimination learning and memory relative to CTL males. WHAT IS KNOWN ALREADY: Some human outcome studies have suggested that ICSI might be associated with an increased risk of certain cognitive disorders, but only one of two behavioral studies with ICSI mouse models have reported differences between ICSI and CTL females. No studies to date have investigated associative learning in ICSI mice. STUDY DESIGN, SIZE, DURATION: Groups of 36 ICSI mice (18 male, 18 female) and 37 CTL mice (19 male, 18 female) aged 3-6 months were compared in a series of operant learning procedures that assessed acquisition of a new behavior, discrimination learning and memory. In total, 16 ICSI mice (9 male, 7 female) and 17 CTL mice (10 male, 7 female) received follow-up discrimination learning and memory assessments at 12 months of age (6 months after the end of initial training) to evaluate retention and reacquisition of learned performances. PARTICIPANTS/MATERIALS, SETTING, METHODS: Mice received daily operant learning sessions in experimental chambers in which all stimulus events and the recording of responses were automated. Food rewards were delivered for responding under different conditions of reinforcement, which varied by procedure. Subjects received a successive series of sessions of nose poke acquisition training, discrimination training and the delayed-non-matching-to-position memory procedure. Mixed repeated measures ANOVAs in which the between-subjects factor was group (ICSI vs CTL) and the within-subjects factor was repeated exposures to learning procedures (i.e. sessions) were used to analyze data. MAIN RESULTS AND THE ROLE OF CHANCE: In comparisons between all mice (i.e. males and females combined), CTL mice exhibited superior performance relative to ICSI in response acquisition (P = 0.03), discrimination (P = 0.001) and memory (P = 0.007). Sex-specific comparisons between the groups yielded evidence of sexual dimorphism. ICSI females exhibited a deficit in acquisition learning relative to CTL females (P < 0.001), but there was not a significant difference between CTL and ICSI males. In the discrimination and memory tasks, ICSI males exhibited deficits relative to CTL males (P = 0.002 and P = 0.02, respectively) but the differences between females in these tasks were not significant. There was no difference in discrimination or memory retention/re-acquisition assessments conducted with mice at 12 months of age. ICSI males and females weighed significantly more than CTL counterparts at all points during the experiment. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: The study was not blinded. All learning assessments utilized food reward; other assessments of operant, Pavlovian and nonassociative learning are needed to fully characterize learning in ICSI mice and speculate regarding the implications for cognitive function in humans conceived via ICSI. WIDER IMPLICATIONS OF THE FINDINGS: Studying learning and memory processes in mouse models have the potential to shed light on ICSI outcomes at the level of cognitive function. Future research should use multiple learning paradigms, assess both males and females, and investigate the effects of variables related to the ICSI procedure. Studying cognitive function in ICSI is an interdisciplinary endeavor and requires co-ordination between researchers at the genetic and psychological levels of analysis. STUDY FUNDING/COMPETING INTEREST(S): This work was supported, in part, by grants from the NIH (P30GM110767, HD071736 and HD085506 to W.Y.), the Templeton Foundation (61174 to W.Y.) and a New Scholarly Endeavor Grant from the University of Nevada, Reno Office of Research and Innovation (to M.L., Y.W., H.Z., L.H. and W.Y.). The authors declare no competing interests.

The State of Teaching Philosophy in Behavior Analysis Training Programs.

Professional organizations that oversee the accreditation of graduate training programs in behavior analysis have increased didactic training requirements for programs in various domains across the years. One of the areas in which this has occurred concerns training in philosophy within behavior science. Although content-hour requirements for didactic philosophical training have increased, the contents of this training are not prescribed and are left to the discretion of individual programs. We conducted a survey of verified course sequence programs to assess the current state of training in philosophy in behavior analysis graduate training programs. The results provided a list of common topics and readings in philosophy courses, and indicated an emphasis on radical behaviorism and the works of B. F. Skinner. The list of topics and readings obtained provides a resource for course design, and we suggest that exposing students to a broader range of behavioristic and nonbehavioristic topics and readings may enhance students' orientation to philosophical issues in behavior analysis. Supplementary Information: The online version contains supplementary material available at 10.1007/s40617-023-00889-8.

Motivational state-dependent renewal and reinstatement of operant responding under food and water deprivation states.

Most studies of operant relapse phenomena have studied the role of exteroceptive discriminative features of context in the recovery of behavior after extinction. Interoceptive stimuli (i.e., stimuli arising from the bodies of organisms) may also serve as a part of learning contexts and contribute to relapse. Recent studies have demonstrated that events that function as motivating operations (MOs) may contribute to relapse both by a) eliciting interoceptive conditions that serve as a discriminative context for relapse (i.e., discriminative function) and b) altering the amount of operant responding in the presence of discriminative stimuli associated with reinforcers (i.e., motivational function). The current study examined interactions between these functions of food and water deprivation MOs in the relapse of operant behavior. During acquisition of an operant response, one group of mice was food-deprived and another was water-deprived. The groups then received extinction sessions under the opposite condition. Renewal and reinstatement tests were conducted under both conditions, and more renewal and reinstatement were observed in the motivational states in which acquisition occurred for each. These results are discussed in the context of state-dependent learning.

A preliminary evaluation of habituation and dishabituation of operant responding in mice.

Previous research has suggested that operant response decrements within experimental sessions are due in part to habituation to the repeated presentation of reinforcers. One way to assess the role of habituation in within-session response decrements is to conduct a test for dishabituation, a phenomenon in which a habituated response to a given stimulus recovers following the presentation of some strong or novel stimulus other than the habituated stimulus. Dishabituation of operant responding has been demonstrated on several occasions in the literature, but studies with non-human subjects have thus far been limited to those using rats and pigeons. Two experiments attempting to replicate these findings with mice were conducted. Two groups of mice nose-poked for a sweetened condensed milk/water reinforcer on either a fixed-ratio 4 or variable-interval 15 s schedule of reinforcement. During testing, baseline sessions were then alternated with two test conditions and a control condition. Test conditions included a 5 s auditory stimulus or flashing of the house light presented mid-session. Control conditions were identical to baseline. Dishabituation was not observed for either group in Experiment 1. In Experiment 2, dishabituation was not observed for the fixed-ratio 4 group but was observed for the variable interval 15 s group. Considerations for further study of operant dishabituation in mice are discussed.

Motivating operations as contexts for operant discrimination training and testing.

Two groups of mice were exposed to stimulus discrimination training and testing under different motivational conditions to study interactions between motivating operations (MOs) during initial discrimination training and MOs when performance is tested following training. One group received all discrimination training sessions under 24-h food deprivation while the other received all sessions under 0-h food deprivation. The number of responses allowed during discrimination training sessions was limited such that the two groups experienced the same number of response-outcome contingencies. The groups then received two post-discrimination training tests: one conducted under 24-h food deprivation and the other conducted under 0-h food deprivation. Results indicated no difference between groups in terms of discrimination ratio. However, subjects trained under 24-h deprivation made more responses in the 24-h test, while subjects trained under 0-h deprivation made more responses in the 0-h test. These results are discussed in terms of motivational state-dependent learning.

Increasing Access and Quality of Behavior-Analytic Services for the Latinx Population.

Latinxs are the largest minority group in the United States, making up approximately 18% of the total population. Although there is a critical need for the behavioral health care system, including behavior analysts, to provide services to support the needs of the Latinx community, access to quality behavioral and mental health services continues to be lacking for the Black, Indigenous, and people of color populations. This article highlights some of the cultural and language factors that should be considered by behavior-analytic providers who have a shared responsibility to make culturally and linguistically appropriate services available to this population. Additionally, recommendations for systemic action across service providers, professional organizations, behavior-analytic training programs, and researchers are suggested to address these barriers. Recommendations for bringing about this systemic change are suggested across three domains: (a) increasing diversity in the behavior-analytic workforce, (b) enhancing training in cultural- and language-related issues, and (c) conducting research on cultural and language adaptations to behavior-analytic evidence-based treatments.

The Will to Fight: Aversion-Induced Aggression and the Role of Motivation in Intergroup Conflicts.

Aggressive behavior is a source of many significant human problems, most notably the catastrophic loss of life and resources that can result from violent conflicts between groups. Aggressive behavior is particularly likely to arise from aversive conditions that function as motivating operations (MOs) that establish the stimulation produced by aggressive acts as reinforcing. We describe the behavior that arises from these circumstances as aversion-induced aggression (AIA) and argue that the MOs associated with AIA are important factors in initiating and sustaining violent conflicts between groups. In support of this, we survey the basic nonhuman research that has demonstrated the aggression-motivating functions of aversive stimuli. We extend our analysis of AIA to humans and describe how the special properties of verbal stimuli serve as the basis for notable differences between AIA in humans and nonhumans. We describe how aversive conditions may be exploited by leaders to establish support for aggression against another group in the pursuit of their objectives. We suggest that conflicts between groups cannot be resolved in the long term unless the motivational conditions from which conflicts arise are alleviated. Aggression is rarely effective in this regard because it exacerbates these conditions. For this reason, we advocate against the use of aggression as a tool for resolving conflicts between groups and consider how behavior science may contribute to the development and evaluation of alternative nonviolent practices.

Behavioral skills training in scent detection research: Interactions between trainer and animal behavior.

Animal trainers working in scent detection programs are responsible for arranging training contingencies as well as for observing and recording animal behavior. We provided behavioral skills training (BST) to animal trainers working with scent detection rats to improve the treatment integrity of scent-detection research sessions. We evaluated the trainers' behavior at baseline and during the sequential introduction of each component of BST (instructions, modeling, and feedback). We observed incremental improvements in treatment integrity with the introduction of each BST component. Posttraining probes revealed that these improvements were sustained at least 3 weeks post-BST. As the trainers' behavior was modified during BST, we observed decrements in measures of rat performance. We discuss the nature of these interactions and their implications for the use of BST in scent detection research and in situations in which intervention with one party produces concomitant effects on the behavior of another.

Interactions between the effects of food and water motivating operations on food- and water-reinforced responding in mice.

Two experiments examined interactions between the effects of food and water motivating operations (MOs) on the food- and water-reinforced operant behavior of mice. In Experiment 1, mice responded for sucrose pellets and then water reinforcement under four different MOs: food deprivation, water deprivation, concurrent food and water deprivation, and no deprivation. The most responding for pellets occurred under food deprivation and the most responding for water occurred under water deprivation. Concurrent food and water deprivation decreased responding for both reinforcers. Nevertheless, water deprivation alone increased pellet-reinforced responding and food deprivation alone likewise increased water-reinforced responding relative to no deprivation. Experiment 2 demonstrated that presession food during concurrent food and water deprivation increased in-session responding for water relative to sessions where no presession food was provided. Conversely, presession water during concurrent food and water deprivation did not increase in-session responding for pellets. These results suggest that a) the reinforcing value of a single stimulus can be affected by multiple MOs, b) a single MO can affect the reinforcing value of multiple stimuli, and c) reinforcing events can also function as MOs. We consider implications for theory and practice and suggest strategies for further basic research on MOs.

Evaluation of the behavioral characteristics of the mdx mouse model of duchenne muscular dystrophy through operant conditioning procedures.

The mdx mouse is an important nonhuman model for Duchenne muscular dystrophy (DMD) research. Characterizing the behavioral traits of the strain relative to congenic wild-type (WT) mice may enhance our understanding of the cognitive deficits observed in some humans with DMD and contribute to treatment development and evaluation. In this paper we report the results of a number of experiments comparing the behavior of mdx to WT mice in operant conditioning procedures designed to assess learning and memory. We found that mdx outperformed WT in all learning and memory tasks involving food reinforcement, and this appeared to be related to the differential effects of the food deprivation motivating operation on mdx mice. Conversely, WT outperformed mdx in an escape/avoidance learning task. These results suggest motivational differences between the strains and demonstrate the potential utility of operant conditioning procedures in the assessment of the behavioral characteristics of the mdx mouse.

The effect of the magnitude of the food deprivation motivating operation on free operant preference in mice.

A number of recent studies have demonstrated that organisms prefer stimuli correlated with food under high deprivation conditions over stimuli correlated with food under low deprivation conditions. The purpose of the present study was to extend the literature on this phenomenon by testing for preference under extinction conditions, testing for preference at baseline, employing a free operant preference test, and using mice as subjects. Our results appear to support the existing literature in that most subjects preferred a stimulus correlated with food under high deprivation conditions in the post-training preference test. We provide an analysis of this phenomenon based on the concept of the motivating operation (MO) and discuss how this analysis suggests a number of avenues for further research on this topic.