The error in total error reduction.

Most models of human and animal learning assume that learning is proportional to the discrepancy between a delivered outcome and the outcome predicted by all cues present during that trial (i.e., total error across a stimulus compound). This total error reduction (TER) view has been implemented in connectionist and artificial neural network models to describe the conditions under which weights between units change. Electrophysiological work has revealed that the activity of dopamine neurons is correlated with the total error signal in models of reward learning. Similar neural mechanisms presumably support fear conditioning, human contingency learning, and other types of learning. Using a computational modeling approach, we compared several TER models of associative learning to an alternative model that rejects the TER assumption in favor of local error reduction (LER), which assumes that learning about each cue is proportional to the discrepancy between the delivered outcome and the outcome predicted by that specific cue on that trial. The LER model provided a better fit to the reviewed data than the TER models. Given the superiority of the LER model with the present data sets, acceptance of TER should be tempered.

Conditioned suppression is an inverted-U function of footshock intensity.

Most theories of associative learning assert that conditioned responding to a target cue is a monotonically increasing function of unconditioned-stimulus (US) intensity. In a lick suppression preparation with rats, a cue was paired with a 0.4-, 0.6-, 0.8-, 1.0-, 1.2-, or 1.4-mA footshock in Experiment 1a, and with a 0.3-, 0.8-, 1.3-, or 1.8-mA footshock in Experiment 1b. Subsequent suppression in response to the cue was an inverted-U function of the US intensity. In Experiment 2, we demonstrated that massive extinction of the training context and compound conditioning can each attenuate the response decrement caused by training with a high-intensity US. The sometimes-competing-retrieval model (Stout & Miller, Psychological Review 114:759-783, 2007) provides a better fit to these data than do several other models of associative learning.

Determinants of extinction in a streamed trial procedure.

The strength of an association between a cue and its outcome is influenced by both the probability of the outcome given the cue and the probability of the outcome in the absence of the cue. Once an association has been formed, extinction is the procedure for reducing responding indicative of the association by repeated presentation of the cue without the outcome. The present experiments tested whether cumulative frequency and/or cumulative duration of these events affects associative extinction in a streamed trial extinction procedure with human participants. Experiment 1 assessed the effects of parametric manipulations of the frequency and duration of either the cue by itself or cue-outcome co-absence. In Experiment 1, participants proved relatively insensitive to manipulation of the event's duration. In contrast, judgements of the association by participants decreased when the frequency of cue-alone events was increased, even when the durations of those events were decreased so that cumulative exposure to the cue was equated. No effect of either the duration or the frequency of cue-outcome co-absence was observed. Experiment 2 demonstrated that the effect of cue-alone (i.e., extinction trial) frequency generalises across a wide range of parameters for initial acquisition achieved by cue-outcome pairings. Experiment 3 tested for an interaction between event duration during initial learning and event duration during extinction. Collectively, these results indicate that the cumulative frequency, and not the cumulative duration, of extinction trials as well as the duration of the cue-outcome co-absences between extinction trials control the effectiveness of an extinction procedure.

Associative interference and nonreinforcement in human contingency learning.

This article reports three experiments comparing the impact on contingency assessment of associative cue interference (proactive, interspersed, and retroactive) and nonreinforcement (latent inhibition, partial reinforcement, and extinction). All three experiments used variants of the rapid trial streaming procedure developed by Allan and collaborators. Participants were exposed to stimulus streams and then asked how likely it was for a target cue to be accompanied (Experiment 1) or to be followed (Experiments 2 and 3) by a target outcome. Experiments 1 and 2 looked at interference and found that when the objective target cue-outcome contingency is positive, interspersed interference is more effective than either proactive or retroactive interference. Experiment 2 additionally showed that this conclusion was a function of the target cue-outcome contingency: when the number of cue-outcome pairings was low, retroactive interference was more efficient than interspersed interference. Experiment 3 examined nonreinforcement and found that the efficacies of latent inhibition, partial reinforcement, and extinction are also a function of the target cue-outcome contingency, but the pattern differed greatly from what was observed in Experiment 2. When the number of cue-outcome pairings was high, there was no difference between latent inhibition, partial reinforcement, and extinction. When the number of cue-outcome pairings was low, extinction did not lower the contingency judgement, whereas latent inhibition and partial reinforcement did.

The dual role of the context in postpeak performance decrements resulting from extended training.

The context's role in Pavlovian conditioning depends on the trial spacing during training, with massed trials revealing a function akin to that of discrete stimuli, and spaced trials revealing a modulatory function (Urcelay & Miller, Journal of Experimental Psychology. Animal Behavior Processes, 36, 268-280, 2010). Here we examined the contextual determinants of a common but largely ignored effect: attenuated conditioned responding with extended reinforced training (i.e., a postpeak performance deficit [PPD]). Contextual sources of PPDs were investigated in four fear-conditioning experiments with rats. In Experiment 1, as the number of reinforced trials increased, conditioned responding decreased, even when testing occurred outside the training context. Experiment 2 revealed opposing influences of context on the PPD based on trial spacing, which interacted with whether testing occurred in the training context. This finding reconciles Experiment 1's results with previous data (Bouton, Frohardt, Sunsay, Waddell, & Morris, Journal of Experimental Psychology. Animal Behavior Processes, 34, 223-236, 2008). Experiment 3 suggested that extended training with these parameters did not lead to habituation to conditioned or unconditioned stimuli. In Experiment 4, few or many massed training trials were followed orthogonally by context extinction or no context extinction. After many pairings, context extinction reduced the PPD (i.e., enhanced responding), suggesting a competitive role of the context. These results, together with prior data suggesting that context modulates expressions of the PPD, are consistent with the view that contexts can play two distinctly different roles.

Performance factors in associative learning: assessment of the sometimes competing retrieval model.

Previous simulations revealed that the sometimes competing retrieval model (SOCR; Stout & Miller, Psychological Review, 114, 759-783, 2007), which assumes local error reduction, can explain many cue interaction phenomena that elude traditional associative theories based on total error reduction. Here, we applied SOCR to a new set of Pavlovian phenomena. Simulations used a single set of fixed parameters to simulate each basic effect (e.g., blocking) and, for specific experiments using different procedures, used fitted parameters discovered through hill climbing. In simulation 1, SOCR was successfully applied to basic acquisition, including the overtraining effect, which is context dependent. In simulation 2, we applied SOCR to basic extinction and renewal. SOCR anticipated these effects with both fixed parameters and best-fitting parameters, although the renewal effects were weaker than those observed in some experiments. In simulation 3a, feature-negative training was simulated, including the often observed transition from second-order conditioning to conditioned inhibition. In simulation 3b, SOCR predicted the observation that conditioned inhibition after feature-negative and differential conditioning depends on intertrial interval. In simulation 3c, SOCR successfully predicted failure of conditioned inhibition to extinguish with presentations of the inhibitor alone under most circumstances. In simulation 4, cue competition, including blocking (4a), recovery from relative validity (4b), and unblocking (4c), was simulated. In simulation 5, SOCR correctly predicted that inhibitors gain more behavioral control than do excitors when they are trained in compound. Simulation 6 demonstrated that SOCR explains the slower acquisition observed following CS-weak shock pairings.

Factors Promoting Posttraumatic Growth in Sexual Minority Adults Following Adolescent Bullying Experiences.

The minority stress model posits that stigmatized identities expose sexual minority individuals to chronic stressors that contribute to health disparities, but that individual-level resources may mitigate psychological distress. Sexual minority adolescents experience one such stressor, bullying victimization, at higher rates than heterosexual peers. Whereas negative consequences of sexual identity-based bullying are well documented, potential positive outcomes are not well understood. The present work examined hypothesized pathways to posttraumatic growth (PTG)-positive psychological changes stemming from trauma-in sexual minority adults following adolescent bullying experiences. We predicted that attributing bullying to one's sexual identity, as opposed to other factors (e.g., weight/appearance, personality), would exacerbate perceived bullying severity but, in turn, enhance PTG. We also predicted that outness about sexual identity would enhance social support and, in turn, facilitate PTG. The hypothesized conceptual model was tested in two samples of sexual minority adults who had experienced bullying during adolescence (Sample 1: Community Sample [N = 139]; Sample 2: National Online Sample [N = 298]), using structural equation modeling with Bayesian estimation. Mediation hypotheses were tested using the PROCESS v3.4 macro. Participants reported their adolescent experiences with bullying, attributions for bullying, outness, social support, and PTG as a result of adolescent bullying experiences, in addition to demographics. Supporting the hypothesized model, in both samples, attributions to sexual identity-based bullying directly and indirectly (via bullying severity) predicted greater PTG, and outness predicted greater PTG through proximal impact on social support. This research underscores the importance of supportive responses to individuals who disclose sexual minority identities and of (re)framing attributions about bullying to facilitate growth.

Benefiting from trial spacing without the cost of prolonged training: Frequency, not duration, of trials with absent stimuli enhances perceived contingency.

The statistical relation between two events influences the perception of how one event relates to the presence or absence of another. Interestingly, the simultaneous absence of both events, just like their mutual occurrence, is relevant for describing their contingency. In three experiments, we explored the relevance of coabsent events by varying the duration and frequency of trials without stimuli. We used a rapid trial streaming procedure and found that the perceived association between events is enhanced with increasing frequency of coabsent events, unlike the duration of coabsent events, which had little effect. These findings suggest ways in which the benefits of trial spacing, during which both events are absent, could be obtained without increasing total training time. Centrally, this can be done by frequent repeating of shortened coabsent events, each marked by a trial contextual cue. We discuss four potential accounts of how coabsent experience might be processed contributing to this effect: (a) contingency sensitivity, (b) testing effect, (c) reduced associative interference by the context, and (d) reduced encoding interference. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

More frequent, shorter trials enhance acquisition in a training session: There is a free lunch!

The strength of the learned relation between two events, a model for causal perception, has been found to depend on their overall statistical relation, and might be expected to be related to both training trial frequency and trial duration. We report five experiments using a rapid-trial streaming procedure containing Event 1-Event 2 pairings (A trials), Event 1-alone (B trials), Event 2-alone (C trials), and neither event (D trials), in which trial frequencies and durations were independently varied. Judgements of association increased with increasing frequencies of A trials and decreased with increasing frequencies of both B and C trials but showed little effect of frequency of D trials. Across five experiments, a weak but often significant effect of trial duration was also detected, which was always in the same direction as trial frequency. Thus, both frequency and duration of trials influenced learning, but frequency had decidedly stronger effects. Importantly, the benefit of more trials greatly outweighed the observed reduction in effect size caused by a proportional decrease in trial duration. In experiment 5, more trials of proportionately shorter duration enhanced effects on contingency judgments despite a shortening of the training session. We consider the observed 'frequency advantage' with respect to both frequentist models of learning and models based on information. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The role of within-compound associations in learning about absent cues.

When two cues are reinforced together (in compound), most associative models assume that animals learn an associative network that includes direct cue-outcome associations and a within-compound association. All models of associative learning subscribe to the importance of cue-outcome associations, but most models assume that within-compound associations are irrelevant to each cue's subsequent behavioral control. In the present article, we present an extension of Van Hamme and Wasserman's (Learning and Motivation 25:127-151, 1994) model of retrospective revaluation based on learning about absent cues that are retrieved through within-compound associations. The model was compared with a model lacking retrieval through within-compound associations. Simulations showed that within-compound associations are necessary for the model to explain higher-order retrospective revaluation and the observed greater retrospective revaluation after partial reinforcement than after continuous reinforcement alone. These simulations suggest that the associability of an absent stimulus is determined by the extent to which the stimulus is activated through the within-compound association.

Two components of responding in Pavlovian lick suppression.

The present research examined the temporal distribution of responding in a lick suppression paradigm. In Experiment 1, rats were trained with either a 30- or a 120-s conditioned stimulus (CS), which was followed either by a footshock (unconditioned stimulus [US]) or nothing. Licking during the CS was suppressed only in the former condition. Suppression was more pronounced early in the CS. In Experiment 2, rats were exposed to two 30-s or two 120-s CSs, with delivery of the shock being contingent on CS1 for half of the animals and on CS2 for the other half. For both the paired and the unpaired conditions, suppression at the beginning of CS1 was observed for all the groups. By discounting the possibility of generalization between CS1 and CS2, it appears that this initial suppression was not a conditioned response to the CS, but an unconditioned one due to mere exposure to the shock US.

A One-System Theory Which is Not Propositional.

We argue that the propositional and link-based approaches to human contingency learning represent different levels of analysis because propositional reasoning requires a basis, which is plausibly provided by a link-based architecture. Moreover, in their attempt to compare two general classes of models (link-based and propositional), Mitchell et al. have referred to only two generic models and ignore the large variety of different models within each class.

An inhibitory within-compound association attenuates overshadowing.

According to the comparator hypothesis (Miller & Matzel, 1988), cue competition depends on the association between a target stimulus (X) and a competing cue (e.g., an overshadowing cue [A]). Thus, it was expected that overshadowing would be reduced by establishing an inhibitory-like relationship between X and A before compound conditioning. In three lever press suppression experiments with rats, this expectation was supported. Experiment 1 showed that establishing an inhibitory X-A relationship reduced overshadowing. In Experiment 2, degrading the inhibitory-like relationship before conditioning allowed reinforced AX compound trials to result in overshadowing. Experiment 3 replicated the results of Experiment 2 when the inhibitory relationship was degraded after compound conditioning. The results support the view that within-compound associations are necessary not only for retrospective revaluation, but also for conventional cue competition.

Reduced blocking as a result of increasing the number of blocking cues.

Weak behavioral control (blocking) occurs when a target stimulus (X) is paired with an outcome in the presence of a well-established signal for the outcome (i.e., a blocking stimulus). Conventional Pavlovian conditioning theories explain this effect by asserting that a discrepancy between expected and experienced outcomes is necessary for learning about X and that no such discrepancy exists in blocking situations. These theories anticipate that the effect of additional well-established signals for the unconditioned stimulus (US) should be additive. In two conditioned barpress suppression experiments using rats as subjects, the opposite result was observed. Experiment 1 provided evidence that blocking was reduced when two blocking stimuli were present during X-US pairings relative to when one blocking stimulus was present. Experiment 2 elaborated on the mechanisms underlying the observations in Experiment 1, while explaining the discrepancy between the results of Experiment 1 and prior reports of the additivity of blocking stimuli.

Degraded contingency revisited: posttraining extinction of a cover stimulus attenuates a target cue's behavioral control.

In a Pavlovian conditioning situation, unsignaled outcome presentations interspersed among cue-outcome pairings attenuate conditioned responding to the cue (i.e., the degraded contingency effect). However, if a nontarget cue signals these added outcomes, responding to the target cue is partially restored (i.e., the cover stimulus effect). In 2 conditioned suppression experiments using rats, the effect of posttraining extinction of the cover stimulus was examined. Experiment 1 found that this treatment yielded reduced responding to the target cue. Experiment 2 replicated this finding, while demonstrating that this basic effect was not due to acquired equivalence between the target cue and the cover stimulus. These results are consistent with the extended comparator hypothesis interpretation of the degraded contingency and cover stimulus effects.

Methods of comparing associative models and an application to retrospective revaluation.

Contemporary theories of associative learning are increasingly complex, which necessitates the use of computational methods to reveal predictions of these models. We argue that comparisons across multiple models in terms of goodness of fit to empirical data from experiments often reveal more about the actual mechanisms of learning and behavior than do simulations of only a single model. Such comparisons are best made when the values of free parameters are discovered through some optimization procedure based on the specific data being fit (e.g., hill climbing), so that the comparisons hinge on the psychological mechanisms assumed by each model rather than being biased by using parameters that differ in quality across models with respect to the data being fit. Statistics like the Bayesian information criterion facilitate comparisons among models that have different numbers of free parameters. These issues are examined using retrospective revaluation data.

Retrospective revaluation: The phenomenon and its theoretical implications.

Retrospective revaluation refers to an increase (or decrease) in responding to conditioned stimulus (CS X) as a result of decreasing (or increasing) the associative strength of another CS (A) with respect to the unconditioned stimulus (i.e., A-US) that was previously trained in compound with the target CS (e.g., AX-US or just AX). We discuss the conditions under which retrospective revaluation phenomena are most apt to be observed and their implications for various models of learning that are able to account for retrospective revaluation (e.g., Dickinson and Burke, 1996; Miller and Matzel, 1988; Van Hamme and Wasserman, 1994). Although retroactive revaluation is relatively parameter specific, it is seen to be a reliable phenomenon observed across many tasks and species. As it is not anticipated by many conventional models of learning (e.g., Rescorla and Wagner, 1972), it serves as a critical benchmark for evaluating traditional and newer models.

Trial spacing during extinction: the role of context-US associations.

Studies of extinction in Pavlovian preparations can identify conditions that make extinction more enduring and increase the benefits of exposure-based behavior therapy. One such potential condition is the use of spaced extinction trials. Nevertheless, contradictory results of spacing extinction trials are found in the existing literature. Here we examine the strength of the association between the extinction context and the unconditioned stimulus as a variable that reconciles the seemingly contradictory prior reports. To assess the role of this variable, we evaluated the effects of extinction trial spacing as a function of the associative status of the extinction context in three lick suppression experiments with rats. In Experiment 1, the associative status of the extinction context was manipulated by giving extinction treatment in either the same context as acquisition or a different context. In Experiment 2, the associative status of the extinction context was initially high as a result of the acquisition context being used for extinction and then it was manipulated through postacquisition context exposure. In Experiment 3, extinction was administered in a context different from that of acquisition and the associative status of the extinction context was manipulated by delivering unsignaled footshock (i.e., the unconditioned stimuli) in the extinction context between acquisition and extinction. In all three experiments, consistently less conditioned suppression was observed with spaced extinction trials relative to massed extinction trials when the associative value of the extinction context was relatively low. In contrast, massed extinction trials produced less conditioned suppression when the associative status of the extinction context was high. Thus, stimulus control after extinction is influenced by an interaction between the intertrial interval during extinction and the associative status of the extinction context.

Associative status of the training context determines the effectiveness of compound extinction.

Studies of extinction of a target cue in compound with another excitor have produced evidence of both deepened and attenuated extinction relative to elemental extinction. The present experiments sought to resolve this discrepancy by assessing the effect of the extinction context-unconditioned stimulus (US) association on compound extinction. In an ABC renewal situation with rats, Experiment 1 replicated the observation that enhanced extinction (i.e., reduced conditioned suppression) occurs as a result of nonreinforcement in compound with a concurrent excitor. In Experiment 2, inflation of the extinction context-US association through unsignaled, intertrial US presentations reversed the effect of a concurrent excitor (i.e., extinction with a concurrent excitor was less effective than elemental extinction). Experiment 3 compared compound extinction and second-order conditioning with respect to the effect of context inflation, and produced results incompatible with the view that second-order conditioning contributed to the results of Experiment 2. In Experiment 4, a concurrent excitor enhanced extinction in ABC renewal and attenuated extinction in AAC renewal. The present results suggest that the effect of a concurrent excitor during extinction depends on the strength of the extinction context-US association, thereby confirming predictions of the sometimes -competing retrieval model of associative acquisition and extinction.

The temporal pattern of responding in conditioned bar-press suppression: the role of the context switch and training mode.

The present study examined the temporal pattern of responding in a conditioned bar-press suppression task in rats. Rats were exposed to either a 30-s or a 120-s conditioned stimulus (CS) followed by a footshock. Training took place either while the rats were lever-pressing for water (online), or with the lever removed from the box (offline). They were then exposed to the CS while they were lever-pressing for water, either in the training context or in a different context. Bar-press suppression during the CS was constant across the duration of the CS during training, but was restricted to the initial portion of the CS at the time of testing, especially when subjects were tested in a different context. Those results replicate the reactive (as opposed to anticipatory) pattern observed in a lick suppression procedure by Jozefowiez et al. (2011) and indicate that a change in context at the time of testing might be critical for its expression.