Previous research has shown that causal attributions can be made from patterns of covariation (Cheng, 1997). While the study of how humans learn contingencies goes back decades (e.g., Ward & Jenkins, 1965), cue interaction effects, involving covariations with two or more cues, have taken on particular importance (e.g., Shanks, 1985), due to their rich potential for theoretical insights. One such effect is causal discounting (Goedert & Spellman, 2005): People believe a cue is less contingent if they learned about it in the presence of a more contingent cue. Using a new method for investigating covariation detection, the steamed-trial technique (Allen et al., 2008), Art Markman, Kelly Goedert and I (Laux et al., 2010) have established that differences in bias underlie causal discounting. We argued that this implies discounting is an effect of a process employed to make causal judgments after learning has occurred. Analyses of how different theories account for discounting, especially simulations of associative models, establishes that this is not necessarily correct; several learning models can reproduce our data. However, model and data explorations show that the key feature of those data is that they track relative, not absolute, magnitudes. My dissertation extends this work establishing the plausibility of a comparative judgment process as the locus of causal discounting. I replicate the finding that responding tracks relative magnitudes. By conducting experiments that parametrically manipulate the contingency of the alternative cue (and thereby the relative contingency of the cues), I show that causal discounting is due to responding to contingencies as a linear function of their relative magnitude. I further verify that discounting manifests identically in response to contingencies presented via summary tables. Because summary tables do not afford the series of experiences necessary to build an association, this enhances the credibility of the theory that discounting is due to a shared process employed subsequent to learning—namely, a judgment process. These investigations reveal that discounting is not a cue interaction effect at all, but rather is a manifestation of a fundamental aspect of the systems that subserve covariation detection. / text

Recent findings indicate that bimodal-redundant stimulation promotes perceptual learning and recruits attention to amodal properties in non-human as well as human infants. However it is not clear if bimodal-redundant stimulation can also facilitate memory during the postnatal period. Moreover, most animal and human studies have employed an operant paradigm to study memory, but have not compared the effectiveness of contingent versus passive presentation of information on memory. The current study investigated the role of unimodal versus bimodal presentation and, the role of a contingent versus passive exposure in memory retention in the bobwhite quail (Colinus virginianus). Results revealed that contingently trained chicks demonstrated a preference for the familiarized call under both unimodal and bimodal conditions. Between-group analyses revealed that the contingent-bimodal group preferred the familiarized call as compared to the passive-bimodal group. These results indicate that the contingency paradigm accompanied with the bimodal stimulus type facilitated memory during early development.

Participants are slower to identify the print colour of incongruent colour words (e.g., the word ORANGE printed in green) than of congruent colour words (e.g., ORANGE printed in orange). The difference in time between these two conditions is the Stroop effect. The item-specific proportion congruent (ISPC) effect is the observation that the Stroop effect is larger for words that are presented mostly in congruent colours (e.g., BLUE presented 75% of the time in blue), and smaller for words that are presented mostly in a given incongruent colour (e.g., YELLOW presented 75% of the time in orange). One account of the ISPC effect, the modulation hypothesis, is that participants use the distracting word to modulate attention to the word (i.e., participants allow the word to influence responding when it is presented mostly in its congruent colour). Another account, the contingency hypothesis, is that participants use the word to predict the response that they will need to make (e.g., if the word is YELLOW, then the response is probably orange). Reanalyses of data from Jacoby, Lindsay, and Hessels (2003) along with results from new experiments are inconsistent with the modulation hypothesis, but entirely consistent with the contingency hypothesis. A mechanistic account of how responses are predicted is generated from the contingency hypothesis.

Participants are slower to identify the print colour of incongruent colour words (e.g., the word ORANGE printed in green) than of congruent colour words (e.g., ORANGE printed in orange). The difference in time between these two conditions is the Stroop effect. The item-specific proportion congruent (ISPC) effect is the observation that the Stroop effect is larger for words that are presented mostly in congruent colours (e.g., BLUE presented 75% of the time in blue), and smaller for words that are presented mostly in a given incongruent colour (e.g., YELLOW presented 75% of the time in orange). One account of the ISPC effect, the modulation hypothesis, is that participants use the distracting word to modulate attention to the word (i.e., participants allow the word to influence responding when it is presented mostly in its congruent colour). Another account, the contingency hypothesis, is that participants use the word to predict the response that they will need to make (e.g., if the word is YELLOW, then the response is probably orange). Reanalyses of data from Jacoby, Lindsay, and Hessels (2003) along with results from new experiments are inconsistent with the modulation hypothesis, but entirely consistent with the contingency hypothesis. A mechanistic account of how responses are predicted is generated from the contingency hypothesis.

Infants begin to learn important skills, such as contingency learning, social referencing, and joint attention through everyday interactions with their environment. When infants learn that their behavior produces a change in the environment (e.g., attention from others), infants engage in behavior that produces that effect (e.g., increases in smiling sustained engagement. When mothers and other caregivers respond immediately to infant behavior, they help their infant learn that the infant’s own behavior is effective, producing a change in the environment. The current investigation evaluated the effect of a computer-based training that aimed at teaching mothers to play a vocal-imitation contingency-learning game. The training included observer-effect methodology, meaning the mothers engaged in observation and evaluation of other mothers engaging in vocal imitation but did not themselves receive any direct coaching or feedback. All mothers completed the training during one session and in less than 45 min. Results indicate that all mothers increased their use of vocal imitation post training and maintained their performance at a two-week follow-up. Results are discussed in terms of how computer training may facilitate dissemination of responsive caregiver training.

<p>One of the most central and current debates among those studying human contingency learning (HCL) concerns whether it is best understood as the result of associative learning, a product of higher-order cognitive processes, or some combination thereof. Though the field appears to be moving toward the latter accounts, much of the evidence being generated to evaluate and select among them comes from tasks that typically present only information about the few variables involved in the contingency(s), in the exact same manner on every trial. While effective for examining how the statistical properties of experience affect learning, these procedures do not capture some of the conditions of everyday cognition and are apt to be less effective for engaging non-associative and top-down influences on performance.</p> <p>The current work introduces a task that involves learning contingencies in others' behavior from descriptions that require the learner to determine the focus of learning, and to deal with both variability in manifestation of the objects of learning and extraneous information. Across several experiments, performance reflects phenomena, including ΔP, outcome density and blocking effects, which have been well established in HCL and are consistent with associative accounts. At the same time, the findings also suggest that (a) domain-specific theories affect the weighting of evidence in contingency perception and the discoverability of contingencies, and (b) outcome predictions, a typical measure in HCL, are influenced by specific instance memory in addition to abstract contingency knowledge. These findings are difficult to reconcile with the data-driven nature of associative views, and join a growing number of demonstrations suggesting that a viable account of HCL must involve higher-order cognitive processes or top-down influences on performance.</p> / Thesis / Doctor of Philosophy (PhD)

Recent studies show that when words are correlated with the colours they are printed in (e.g., MOVE is presented 75% of the time in blue), colour identification is faster when the word is presented in its expected colour (MOVE in blue) than in an unexpected colour (MOVE in green). The present series of experiments explored the possible mechanisms involved in this colour-word contingency learning effect. Experiment 1 demonstrated that the effect was already present after 18 learning trials. During subsequent unlearning, the effect extinguished equally rapidly, suggesting that only a handful of the most recently encountered trials are used to predict responses. Two reanalyses of data from Schmidt, Crump, Cheesman, and Besner (2007) ruled out an account of the effect in terms of stimulus repetitions. Experiments 2 and 3 demonstrated that participants who carry a memory load do not show a contingency effect, supporting the hypothesis that limited-capacity resources are used to retrieve a small number of trial memories in order to prepare a response. Experiment 4 demonstrated that memory resources are required for both storage and retrieval processes.

Recent studies show that when words are correlated with the colours they are printed in (e.g., MOVE is presented 75% of the time in blue), colour identification is faster when the word is presented in its expected colour (MOVE in blue) than in an unexpected colour (MOVE in green). The present series of experiments explored the possible mechanisms involved in this colour-word contingency learning effect. Experiment 1 demonstrated that the effect was already present after 18 learning trials. During subsequent unlearning, the effect extinguished equally rapidly, suggesting that only a handful of the most recently encountered trials are used to predict responses. Two reanalyses of data from Schmidt, Crump, Cheesman, and Besner (2007) ruled out an account of the effect in terms of stimulus repetitions. Experiments 2 and 3 demonstrated that participants who carry a memory load do not show a contingency effect, supporting the hypothesis that limited-capacity resources are used to retrieve a small number of trial memories in order to prepare a response. Experiment 4 demonstrated that memory resources are required for both storage and retrieval processes.

Retrospective revaluation— learning about implied but unpresented cues— poses one of the greatest challenges to classical learning theories. Whereas theorists have revised their models to accommodate revaluation, the empirical reliability of the phenomenon remains contentious. I present two sets of experiments that examine revaluative learning under different but analogous experimental protocols. Results provided mixed empirical evidence that is difficult to interpret in isolation. To address the issue, I apply two computational models to the experiments. An instance-based model of associative learning (Jamieson et al., 2012) predicts retrospective revaluation and anticipates participant behaviour in one set of experiments. An updated classical learning model (Ghirlanda, 2005) fails to predict retrospective revaluation, but anticipates participant behaviour in the other set of experiments. I argue that retrospective revaluation emerges as a corollary of basic memorial processes and discuss the empirical and theoretical implications.

Retrospective revaluation— learning about implied but unpresented cues— poses one of the greatest challenges to classical learning theories. Whereas theorists have revised their models to accommodate revaluation, the empirical reliability of the phenomenon remains contentious. I present two sets of experiments that examine revaluative learning under different but analogous experimental protocols. Results provided mixed empirical evidence that is difficult to interpret in isolation. To address the issue, I apply two computational models to the experiments. An instance-based model of associative learning (Jamieson et al., 2012) predicts retrospective revaluation and anticipates participant behaviour in one set of experiments. An updated classical learning model (Ghirlanda, 2005) fails to predict retrospective revaluation, but anticipates participant behaviour in the other set of experiments. I argue that retrospective revaluation emerges as a corollary of basic memorial processes and discuss the empirical and theoretical implications.