Conjugate Reinforcement Research Articles

Multiple schedules of conjugate reinforcement and extinction: A translational model for assessing automatically reinforced behavior.

This study evaluated the extent to which a conjugate reinforcement schedule (CONJ) involving a contingency between pedaling a stationary bike and viewing a preferred movie could serve as a translational preparation for the analysis of automatically reinforced behavior. In part, researchers examined whether providing participants with either an accurate or an inaccurate rule about the extinction (EXT) component of a multiple schedule (MULT) contributed to the development of control by the MULT (CONJ EXT) schedule. Results show schedule control emerged for four of five participants who received the accurate rule and none of the five participants who received the inaccurate rule. In addition, participants who received accurate rules typically increased pedaling during CONJ components that followed two consecutive EXT components, suggesting that they experienced deprivation for audio and visual stimulation generated by pedaling. These preliminary findings suggest that researchers could use this translational preparation to identify matched interventions for some automatically reinforced behavior.

Neonatal brain metabolite concentrations: Associations with age, sex, and developmental outcomes.

Age and sex differences in brain metabolite concentrations in early life are not well understood. We examined the associations of age and sex with brain metabolite levels in healthy neonates, and investigated the associations between neonatal brain metabolite concentrations and developmental outcomes. Forty-one infants (36–42 gestational weeks at birth; 39% female) of predominantly Hispanic/Latina mothers (mean 18 years of age) underwent MRI scanning approximately two weeks after birth. Multiplanar chemical shift imaging was used to obtain voxel-wise maps of N-acetylaspartate (NAA), creatine, and choline concentrations across the brain. The Bayley Scales of Infant and Toddler Development, a measure of cognitive, language, and motor skills, and mobile conjugate reinforcement paradigm, a measure of learning and memory, were administered at 4 months of age. Findings indicated that postmenstrual age correlated positively with NAA concentrations in multiple subcortical and white matter regions. Creatine and choline concentrations showed similar but less pronounced age related increases. Females compared with males had higher metabolite levels in white matter and subcortical gray matter. Neonatal NAA concentrations were positively associated with learning and negatively associated with memory at 4 months. Age-related increases in NAA, creatine, and choline suggest rapid development of neuronal viability, cellular energy metabolism, and cell membrane turnover, respectively, during early life. Females may undergo earlier and more rapid regional developmental increases in the density of viable neurons compared to males.

The Active Sensing of Control Difference.

SummaryIn everyday life, people control objects in the world around them to varying degrees. The processes people actively use to establish their control, while interacting with an environment containing large ambiguity, remain unknown. This study examines how people explore their control over the environment and how they detect small differences in control among objects. In the experimental task, participants moved three dots on a screen and identified one dot over which the level of control is different from that of the other two. The results support a two-step behavior mechanism underlying the sensing of control difference: People first explore their overall control in the environment, and then the results of the initial exploration are used to selectively tune the direction (i.e., either more or less) of the detected control difference, ensuring efficient and rapid detection of the type of control difference that is potentially important for further action selections.

Associations between different dimensions of prenatal distress, neonatal hippocampal connectivity, and infant memory

Prenatal maternal distress—an umbrella concept encompassing multiple negative psychological states including stress, anxiety, and depression—is a substantial prenatal exposure. Consistent across preclinical and human studies, the hippocampus displays alterations due to prenatal distress. Nevertheless, most prenatal distress studies do not focus on multiple dimensions of, have not examined hippocampal functional connectivity in association with, and do not consider observer-based functional outcomes related to distress. We investigated the effects of different dimensions of prenatal distress in pregnant adolescents, a population at high risk for distress, in association with neonatal hippocampal connectivity and infant memory. In pregnant adolescents (n = 42), we collected four measures of distress (perceived stress, depression, pregnancy-specific distress, and 24-h ambulatory salivary cortisol) during the 2nd and 3rd trimesters. Resting-state imaging data were acquired in their infants at 40–44 weeks post-menstrual age. Functional connectivity was measured from hippocampal seeds. Memory abilities were obtained at 4 months using the mobile conjugate reinforcement task. Shared across different dimensions of maternal distress, increased 3rd trimester maternal distress associated with weaker hippocampal–cingulate cortex connectivity and stronger hippocampal–temporal lobe connectivity. Perceived stress inversely correlated while hippocampal–cingulate cortex connectivity positively correlated with infant memory. Increased cortisol—collected during the 2nd, but not the 3rd, trimester—associated with weaker hippocampal–cingulate cortex connectivity and stronger hippocampal–temporal lobe connectivity. Different dimensions of prenatal maternal distress likely contribute shared and unique effects to shaping infant brain and behavior.

Extinction and Response Force in Conjugate Schedules

In a series of experiments with undergraduate participants, we used a force-transducing device to determine how response force varies across different conjugate reinforcement and extinction conditions. In Experiment 1, we assessed how different parameters of response-contingent volume change in audiovisual stimuli maintained conjugate responding on a force transducer during conjugate reinforcement and extinction components. Response force and schedule force-multiplier values covaried, such that response force tended to decrease as force multipliers increased. Furthermore, proportionally greater response force was observed in extinction components following denser (i.e., 100x conjugate reinforcement) components compared to leaner (i.e., 5x conjugate reinforcement) components. In Experiment 2, we assessed the degree to which responding was maintained when conjugate changes in the audiovisual stimuli were delivered response-contingently or response-independently across reinforcement and extinction components. Response-independent reinforcer delivery yielded mixed results, but mean response force was proportionally higher in extinction sessions for all four participants following response-independent reinforcer delivery compared to extinction following response-contingent reinforcer delivery. Results from this project highlight the utility of the preparation described by Falligant, Rapp, Brogan, and Pinkston (2018) for studying response force in conjugate schedules to assess extinction-induced variability.

The mobile conjugate reinforcement paradigm in a lab setting.

The mobile conjugate reinforcement task was administered to 4-month-old infants in a lab rather than a home setting where it is usually administered. Learning and retention patterns were comparable to those of infants tested in their homes, suggesting flexibility in where this task can be administered. These results pave the way for this task to be used with a broader range of infants for whom home visits are not practical or convenient (e.g., infants in child care). Developmental research conducted with a more diverse population of infants would facilitate our understanding of cognitive development very early in life.

Anticipatory eye movements and long-term memory in early infancy.

Advances in our understanding of long-term memory in early infancy have been made possible by studies that have used the Rovee-Collier's mobile conjugate reinforcement paradigm and its variants. One function that has been attributed to long-term memory is the formation of expectations (Rovee-Collier & Hayne, 1987); consequently, a long-term memory representation should be established during expectation formation. To examine this prediction and potentially open the door on a new paradigm for exploring infants' long-term memory, using the Visual Expectation Paradigm (Haith, Hazan, & Goodman, 1988), 3-month-old infants were trained to form an expectation for predictable color and spatial information of picture events and emit anticipatory eye movements to those events. One day later, infants' anticipatory eye movements decreased in number relative to the end of training when the predictable colors were changed but not when the spatial location of the predictable color events was changed. These findings confirm that information encoded during expectation formation are stored in long-term memory, as hypothesized by Rovee-Collier and colleagues. Further, this research suggests that eye movements are potentially viable measures of long-term memory in infancy, providing confirmatory evidence for early mnemonic processes.

Carolyn Rovee-Collier's legacy to applied psychology, intervention, and public policy.

In this article, we reflect upon Carolyn Rovee-Collier's pioneering research on learning and memory in infants, especially that using the mobile conjugate reinforcement task, for our understanding of (a) cognitive development in infants born prematurely and those with Down's syndrome and (b) her prediction that infants' performance in the mobile conjugate reinforcement and similar operant tasks would predict later intellectual functioning. We then examine the implications of her research on time windows (the integration of new information into a memory) and memory reactivation (the retrieval of a forgotten memory as a result of the re-exposure to a component of the original learning experience) for early intervention programs and clinicians treating victims of early trauma. We conclude with a discussion of the value of Rovee-Collier's work for the growing field of infant/toddler science and how this science has informed public policy and program development.

The coordination dynamics of mobile conjugate reinforcement.

What we know about infant learning and memory is founded largely on systematic studies by the late Carolyn Rovee-Collier (1942-2014) and her associates of a phenomenon called mobile conjugate reinforcement. Experiments show that when a ribbon is attached from a 3-month-old infant's foot to a mobile suspended overhead the baby quickly realizes it can make the mobile move. The mobile, which offers interesting sights and sounds, responds conjugately to the baby's vigorous kicks which increase in rate by a factor of 3-4. In this paper, using the concepts, methods and tools of coordination dynamics, we present a theoretical model which reproduces the experimental observations of Rovee-Collier and others and predicts a number of additional features that can be experimentally tested. The model is a dynamical system consisting of three equations, one for the baby's leg movements, one for the jiggling motion of the mobile and one for the functional coupling between the two. A key mechanism in the model is positive feedback which is shown to depend sensitively on bifurcation parameters related to the infant's level of attention and inertial properties of the mobile. The implications of our model for the dynamical (and developmental) origins of agency are discussed.

Revisiting conjugate schedules.

The effects of conjugate reinforcement on the responding of 13 college students were examined in three experiments. Conjugate reinforcement was provided via key presses that changed the clarity of pictures displayed on a computer monitor in a manner proportional to the rate of responding. Experiment 1, which included seven parameters of clarity change per response, revealed that responding decreased as the percentage clarity per response increased for all five participants. These results indicate that each participant's responding was sensitive to intensity change, which is a parameter of conjugate reinforcement schedules. Experiment 2 showed that responding increased during conjugate reinforcement phases and decreased during extinction phases for all four participants. Experiment 3 also showed that responding increased during conjugate reinforcement and further showed that responding decreased during a conjugate negative punishment condition for another four participants. Directions for future research with conjugate schedules are briefly discussed.

Motor contingency learning and infants with Spina Bifida.

Infants with Spina Bifida (SB) were compared to typically developing infants (TD) using a conjugate reinforcement paradigm at 6 months-of-age (n = 98) to evaluate learning, and retention of a sensory-motor contingency. Analyses evaluated infant arm-waving rates at baseline (wrist not tethered to mobile), during acquisition of the sensory-motor contingency (wrist tethered), and immediately after the acquisition phase and then after a delay (wrist not tethered), controlling for arm reaching ability, gestational age, and socioeconomic status. Although both groups responded to the contingency with increased arm-waving from baseline to acquisition, 15% to 29% fewer infants with SB than TD were found to learn the contingency depending on the criterion used to determine contingency learning. In addition, infants with SB who had learned the contingency had more difficulty retaining the contingency over time when sensory feedback was absent. The findings suggest that infants with SB do not learn motor contingencies as easily or at the same rate as TD infants, and are more likely to decrease motor responses when sensory feedback is absent. Results are discussed with reference to research on contingency learning in infants with and without neurodevelopmental disorders, and with reference to motor learning in school-age children with SB.

Infant memory.

This article provides an overview of developments in long-term memory during the first 2 years of life. Results from three of the most commonly used techniques to assess remembering in preverbal infants-visual paired comparison and visual habituation, conjugate reinforcement, and elicited and deferred imitation-are described. They illustrate infants' ability to encode and retain information as well as the rapid improvements in memory in infancy. A distinction between types or forms of memory is provided in the service of considering how infant memory abilities relate to memory development in early childhood. The review also features discussion of the likely sources of age-related changes in memory in infancy, including the basic processes of memory trace formation and developments in the neural substrate that subserve them. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website.

Effects of conditioning reinforcement for print stimuli on match-to-sample responding in preschoolers.

Introduction One of the major challenges in the fields of education, psychology, and speech therapy is to develop science based research procedures to teach children with language disabilities how to acquire repertoires for learning more complex verbal skills. Keohane, Delgado, and Greer (2008) argue that the foundations for the development of early verbal language in children consists of child's observing responses such as looking, listening, tasting, smelling and touching. When observing responses such as looking and making sustained eye contact with adults and other visual stimuli do not function as conditioned reinforcement for children, these children fail to develop correspondence between what they hear and see concurrently. Moreover, children that lack these conditioned reinforcers for observing responses are likely to find it difficult, if not impossible, to learn more complex skills such as language acquisition, generalized matching and becoming more aware of different stimuli in their environment. Children with disabilities often have difficulty attending and discriminating among the relevant properties of stimuli to master both basic and generalized matching. Greer and Ross (2008) based on Skinner's (1957) theory of verbal behavior identified this deficit (lack of observing/attention to instructional) stimuli as developmental capability or Drawing on Ruiz and Baer's (1997) treatment of the acquisition of critical repertoires as behavioral developmental cusps, Greer and Ross summarized body of research that they argue identify several verbal developmental They suggest that these building blocks make it possible for children to learn listener and speaker responses and the joining of listener and speaker repertoires that make progressively more complex verbal behavior possible. Ruiz and Baer characterized developmental cusp as a special instance of behavior, change crucial to what can come next.... (p. 533). Several years earlier Staats (1968, p. 267) suggested something like behavioral developmental cusps. Several verbal developmental cusps and stages have been identified in the research literature and described as verbal developmental capabilities. The very earliest foundations for verbal development include cusps that consist of conditioned reinforcement for observing responses (Dinsmoor, 1985; Donahoe & Palmer, 2004; Greer & Ross, 2008) Recently, Keohane, Greer, & Ackerman (2006), tested the effects of conditioning sustained eye contact with three-dimensional (3D) objects (Visual Tracking Protocol) on the acquisition of matching responses for participant for whom looking at or observing 3D instructional stimuli on table that were not reinforcers for visual observing responses. They found that when 3D stimuli were paired with unconditioned reinforcers (e.g. food) until the 3D stimuli alone reinforced observing, the participants' mean-learn-units-to criteria dramatically decreased for learning match-to-sample instruction, and also his attending skills increased. The stimuli were conditioned as reinforcers for observing after the stimulusstimulus paring, which resulted in significant decreases in the numbers of learn units the participants required to master visually related instructional material. The significant acceleration in rate of learning for these participants suggest the role of conditioned reinforcement for observing responses as developmental cusp, since the participants could learn discriminations they could not learn prior to intervention. The newly conditioned reinforcers for observing responses constituted acquisition of developmental cusp. Keohane, Delgado, and Greer (2008), surmised that observing responses in children are tied to and are result of conditioned reinforcement for observing. When child is missing this capability, experimentally based conjugate reinforcement procedures or stimulus-stimulus pairing procedure can be used to induce conditioned reinforcement for observing responses for print and 3D instructional stimuli. …

Conjugate reinforcement: a brief review and suggestions for applications to the assessment of automatically reinforced behavior

AbstractProcedures involving conjugate reinforcement have been used extensively by researchers in developmental psychology, but sparingly by behavior analysts. Based on this trend, this paper calls for a re‐examination of conjugate reinforcement as a tool for analyzing automatically reinforced behavior. To this end, studies involving popular conjugate reinforcement preparations are briefly reviewed to highlight the impact of conjugate reinforcement outside of behavior analysis. In addition, results from selected behavior analytic studies are compared to studies involving conjugate reinforcement procedures. Throughout the review, recommendations for extending conjugate reinforcement preparations to the assessment of automatically reinforced behavior are provided. Copyright © 2008 John Wiley & Sons, Ltd.

Assoziation zwischen der Kompetenz zur Kontingenzerkennung im Alter von drei und sechs Monaten und dem Entwicklungsstand im Alter von ein und zwei Jahren

Zusammenfassung. Berichtet wird über eine Längsschnittstudie mit vier Untersuchungszeitpunkten an 87 Kindern im Alter von 3 bis 24 Monaten. Ziel war es, die Assoziationen zwischen Kompetenzen zur nicht-sozialen Kontingenzwahrnehmung mit drei und sechs Monaten und dem späteren Entwicklungsstand mit einem bzw. zwei Jahren sowie der sprachlichen Entwicklung mit zwei Jahren zu analysieren. Die Kompetenz zur Wahrnehmung nicht-sozialer Kontingenzen wurde mittels Mobile Conjugate Reinforcement Paradigma (Mobiletest) sowie Visual Expectation Paradigma (VEP) erhoben. Der Entwicklungsstand wurde mit dem Entwicklungstest 6 Monate - 6 Jahre (ET 6-6) erhoben, die sprachliche Entwicklung mittels des Sprachtests für zweijährige Kinder (SETK-2). Es zeigte sich, dass die Ergebnisse des Mobiletests mit drei Monaten signifikante Bezüge zur Sprachentwicklung mit zwei Jahren aufwiesen. Das VEP mit sechs Monaten stand ebenfalls mit der Sprachentwicklung mit zwei Jahren, zusätzlich aber auch mit der kognitiven und sozialen Entwicklung mit einem Jahr in Verbindung. Diskutiert werden neben der Notwendigkeit zu einer altersspezifischen Differenzierung zwischen den beiden Paradigmen zur Wahrnehmung nicht-sozialer Kontingenzen auch die möglichen Verbindungslinien zwischen nicht-sozialer Kontingenzwahrnehmung und Entwicklung.

Predicting Adolescent Anxiety Ratings From Infant Behavioral Style in Response to Expectancy Violation

Nearly 15 years after infants participated in an operant conditioning task, contact was once again established with the former participants to determine relations between infant behavior in response to expectancy violation during mobile conjugate reinforcement and reported anxiety ratings during adolescence. Shifting infants from a high-stimulation reinforcement contingency to a low-stimulation contingency violated expectancy during the learning task, which elicited negative reactivity, crying, in a number of infants. Original participants and 1 parent were later asked to complete a behavioral assessment questionnaire. Results were consistent with studies that have established relations between early negative reactivity and later internalizing behavior. Infant negative reactivity and poor environmental regulation together significantly contributed to the prediction of higher ratings on a later anxiety scale. Also, infant fear and crying were related and higher fear predicted higher anxiety. Findings also suggested fear is a distinct negative emotional reaction and even early in development can be differentiated from other negative reactivity styles.

Cortisol, contingency learning, and memory in preterm and full-term infants

Cortisol plays an important role in learning and memory. An inverted-U shaped function has been proposed to account for the positive and negative effects of cortisol on cognitive performance and memory in adults, such that too little or too much impair but moderate amounts facilitate performance. Whether such relationships between cortisol and mental function apply to early infancy, when cortisol secretion, learning, and memory undergo rapid developmental changes, is unknown. We compared relationships between learning/memory and cortisol in preterm and full-term infants and examined whether a greater risk for adrenal insufficiency associated with prematurity produces differential cortisol-memory relationships. Learning in three-month old (corrected for gestational age) preterm and full-term infants was evaluated using a conjugate reinforcement mobile task. Memory was tested by repeating the same task 24h later. Salivary cortisol samples were collected before and 20 min after the presentation of the mobile. We found that preterm infants had lower cortisol levels and smaller cortisol responses than full-term infants. This is consistent with relative adrenal insufficiency reported in the neonatal period. Infants who showed increased cortisol levels from 0 to 20 min on Day 1 had significantly better memory, regardless of prematurity, than infants who showed decreased cortisol levels.

Brief report: The reinforcing effects of paternal verbal stimulation and gentle pushing on kicking behavior in a 35 week old in-utero fetus.

Several studies have shown that new borne infants can respond to paternal verbalization and this stimulation can serve as a reinforcer to increase behavior. To date no studies exist demonstrating operant behavior prenatally. This study looks at the possible reinforcing effects of parental stimulation and gentle pushing on a 35 week old in-utero fetus. Using an ABAB reversal design, the experimenters observed the rate of kicking behavior over a four successive three minute periods. The results indicate that verbal statements combined with gentle touch can serve as a reinforcer for in utero fetus to kick. Key words: Prenatal, operant conditioning, kicking response, continuous reinforcement ********** While some studies exist of operant conditioning in neonates, no studies could be found of operant conditioning of prenatal fetuses. Neonate studies do imply a role for prenatal learning (Krueger, Holditch-Davis, Quint & DeCasper, 2004). Using the orienting response, DeCasper offers evidence neonates can differentiate their mother's voices from other female voices and that maternal voice is a more effective reinforcer when compared to other female voices (DeCasper & Fifer, 1980; DeCasper & Spence, 1986; Spence & DeCasper, 1987). Infant's discrimination between passages with content read by mother in uterus were analyzed post natal. In addition, neonates prefer the familiar passage over the novel passage. This occurs regardless of whether the passage is recited by the infant's mother or an unfamiliar woman (DeCasper & Spence, 1986). Finally, while father's voice has not been shown to function as a reinforcer, neonates can differentiate their father's voice from other male voices (DeCasper & Prescott, 1984). Each of the previous examples of preference could be achieved through simple prenatal respondent conditioning. In new born infants extensive work has been conducted using operant conditioning procedures (Perez, & Gewirtz, 1999, May). One example, remembering in infants was studied using operant methods such as mobile conjugate reinforcement (Merriman, Rovee-Collier & Wilk, 1997). Another example and one that has some relevance to this study, the kicking behavior has shown to have operant characteristics (Galloway & Thelen, 2004). Researchers have developed improved methods of exploring the kicking response in neonates (Kraebel, Fable & Gerhardstein, 2004). The current study came about after several sessions of playing by parents informally, using similar procedures to the procedure reported in the method section of this study. This study would add to the literature by extending the operant conditioning process to prenatal infants. METHODS Participants Parents are Caucasian male and female both in late 30's. Both parents have advanced degrees in behavior analysis. The fetus is female and in her 35th week of development. The fetus is typically developing and at the time of the study was oriented into the upside down position for birthing. The infant has regular periods of activity in which it kicks/stretches. Design After several informal sessions of contingent touching of the fetus's foot and stating baby, boom-boom parents decided to formally try to explore the relationship between contingent touch, plus vocal sound, and kicking behavior. Mother sat in a reclining position. Father placed his hand lightly above the skin to be able to feel the kicking. Previous sessions had shown that touching more then lightly prevented mother from being able to identify infant kicking. Father's mouth was one inch from skin in the proximate position where the head would be. The sessions were continuous. Each session lasted for three minutes. In phase one, the fetus's kicking was observed and counted. Only kicks that stretched the skin and could be seen and felt by parents were counted. In phase two, fetus was on a continuous reinforcement schedule. …

The Performance of Infants Born Preterm and Full-term in the Mobile Paradigm: Learning and Memory

By 3 to 4 months of age, infants born full-term and without known disease display associative learning and memory abilities in the mobile paradigm, where an infant's leg is tethered to a mobile such that leg kicks result in proportional mobile movement. The first purpose of this study was to examine the learning and memory abilities of a group of infants born full-term compared with those of a comparison group. Little is known about the learning and memory abilities in infants born preterm, a group at known risk for future impairments in learning and movement. The second purpose of this study was to determine if and when an age-adjusted group of infants born prematurely display associative learning and memory abilities over a 6-week period. Ten infants born full-term (38-42 weeks gestational age [GA]) and 10 infants born preterm (<33 weeks GA and <2,500 g) who were tethered and had control over the mobile movement were independently compared with a comparison group of 10 infants born full-term who were tethered and viewed a moving mobile but did not have control over the mobile movement. Infants in all 3 groups were seen at 3 to 4 months of age and were excluded from participation for any known visual or orthopedic diagnoses. Infants were tested using the mobile conjugate reinforcement paradigm, where one leg is tethered to an overhead mobile such that kicking with that leg results in proportional mobile movement. The kicking rates of the full-term group and the preterm group were compared with their own initial (baseline) kicking rates and with those of the comparison group. After exposure to the conjugate relationship between kicking and mobile movement, the full-term group kicked more frequently compared with their own baseline levels and compared with the comparison group, fulfilling both criteria for learning and memory. In contrast, the preterm group did not increase their kicking rate according to both criteria. These results suggest that infants born prematurely differ in their performance in the mobile paradigm as compared with age-matched infants born full-term. The mobile paradigm may provide clinicians with an important early assessment of infants' associative learning and memory abilities. Follow-up studies are needed, however, to further validate this paradigm as a clinical assessment tool.

Measuring infant memory: Does the ruler matter?

Although the mobile conjugate reinforcement, deferred imitation, and visual attention paradigms are commonly used to test memory processing by infants, there is often debate about the comparability of memory measured by these three procedures. In a series of experiments, we systematically compared 6-month-old infants' performance across all three procedures. Contrary to current claims, measures of memory obtained using the mobile conjugate reinforcement and deferred imitation paradigms were more similar than those obtained using the deferred imitation and visual attention paradigms.