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2. Theory protection in human associative learning and formally representing uncertainty about novel stimuli

Author

Spicer, Stuart Gordon

Subjects
153.1, Associative learning, Theory protection, Prediction error, Confidence, Uncertainty, Beliefs, Computational modelling, Experimental psychology
Abstract

Three collections of data are presented in this thesis, with the broad aim of investigating a potential role for theory protection in human associative learning. According to theory protection, people should resist updating their existing knowledge (i.e. resist new learning), even when faced with evidence that contradicts what they already know. In other words, people should maintain established associations between environmental cues and outcomes wherever possible. Theory protection differs from typical prediction error accounts of learning (e.g. Bush & Mosteller, 1951; Rescorla & Wagner, 1972; Rescorla, 2001). According to prediction error accounts, people should update existing associations (i.e. learn) most readily when the outcomes they encounter are most discrepant with what they predict. Details about these accounts are introduced in Chapter 1, along with several other theories and phenomena that are central to the subsequent chapters. In the first set of experiments (reported in Chapter 2), human participants were initially trained with a set of cues, each of which was followed by the presence or absence of an outcome. In a subsequent training stage, two of these cues were trained together, and the amount learned about each of the cues was compared, using a procedure based on Rescorla (2001). In each experiment, the cues differed in both their prediction error (with respect to the outcome), and the confidence participants should have about their causal status. The cue with the larger prediction error was always the cue with lower confidence about its causal status. In an apparent violation of prediction error, participants always learned more about the cue with the smaller prediction error, supporting a theory protection account of learning. Participants appeared to protect their existing beliefs about cues with a known causal status, instead attributing unexpected outcomes to cues with a comparatively ambiguous causal status. The second set of experiments (reported in Chapter 3) provides further evidence of theory protection, except that the cues, outcomes and experimental scenario differed to those in the Chapter 2 experiments. Chapter 3 also includes direct testing of the theory protection account against the predictions of both Pearce and Hall’s (1980), and Mackintosh’s (1975) attentional accounts of learning. The results were not consistent with either attentional theory. The final set of data (reported in Chapter 4) includes the results of formal model fitting simulations. The findings illustrate a simple way of representing participants’ lack of confidence about the causal status of novel cues. This was achieved by allowing the initial strength of associations (between cues and outcomes) to be an intermediate value. Importantly, the best fitting initial associative strength was shown to change in line with the overall proportion of trials on which the outcome occurs. Free and open resources to support formal modelling in associative learning are briefly introduced. Chapter 5 provides a general discussion of all the findings, whilst also setting out a future programme of research, so that the theory protection account can be developed into a formal model of human associative learning.

Published
2020

5. What is the volume, quality and characteristics of evidence relating to the effectiveness and cost‐effectiveness of multi‐disciplinary occupational health interventions aiming to improve work‐related outcomes for employed adults? An evidence and gap map of systematic reviews

Author

Shaw, Elizabeth, primary, Nunns, Michael, additional, Spicer, Stuart G., additional, Lawal, Hassanat, additional, Briscoe, Simon, additional, Melendez‐Torres, G. J., additional, Garside, Ruth, additional, Liabo, Kristin, additional, and Coon, Jo Thompson, additional

Published
2024
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10. Longitudinal realist evaluation of the Dementia PersonAlised Care Team (D-PACT) intervention: protocol

Author

Wheat, Hannah, primary, Weston, Lauren, additional, Oh, Tomasina M, additional, Morgan-Trimmer, Sarah, additional, Ingram, Wendy, additional, Griffiths, Sarah, additional, Sheaff, Rod, additional, Clarkson, Paul, additional, Medina-Lara, Antonieta, additional, Musicha, Crispin, additional, Spicer, Stuart, additional, Ukoumunne, Obioha, additional, Allgar, Victoria, additional, Creanor, Siobhan, additional, Clark, Michael, additional, Quinn, Cath, additional, Gude, Alex, additional, McCabe, Rose, additional, Batool, Saqba, additional, Smith, Lorna, additional, Richards, Debra, additional, Shafi, Hannah, additional, Warwick, Bethany, additional, Lasrado, Reena, additional, Hussain, Basharat, additional, Jones, Hannah, additional, Dalkin, Sonia, additional, Bate, Angela, additional, Sherriff, Ian, additional, Robinson, Louise, additional, and Byng, Richard, additional

Published
2023
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24. Loot boxes, problem gambling and problem video gaming: A systematic review and meta-synthesis.

Author

Spicer, Stuart Gordon, Nicklin, Laura Louise, Uther, Maria, Lloyd, Joanne, Lloyd, Helen, and Close, James

Subjects
*VIDEO gambling, *COMPULSIVE gambling, *VIDEO game reviewing, *META-analysis, *PILLAGE, *VIDEO games
Abstract

Loot boxes (LBs) are video game-related purchases with a chance-based outcome. Due to similarities with gambling, they have come under increasing scrutiny from media, academics and policymakers alike. Initial evidence suggested that LB engagement might be associated with both problem gambling (PG) and problem video gaming (PVG). We therefore conducted a systematic review of the evidence for associations between LB purchasing, PG and PVG. For LB/PG, 12 of 13 publications reported a positive relationship, with a moderately sized mean effect of r =.27. For LB/PVG, the mean effect was r =.40, although this finding was drawn from only six surveys in total. For PG/PVG, the mean effect was r =.21, with only 11 of 20 studies reporting significant effects. While further evidence is required to determine the direction of causality, the strength of relationships suggests that policy action on LBs may have benefits for harm minimisation. [ABSTRACT FROM AUTHOR]

Published
2022
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26. Crossing boundaries: Global reorientation following transfer from the inside to the outside of an arena.

Author

Buckley, Matthew, Holden, Luke, Spicer, Stuart, Smith, AD, Haselgrove, M, Buckley, Matthew, Holden, Luke, Spicer, Stuart, Smith, AD, and Haselgrove, M

Abstract

In 2 spatial navigation experiments, human participants were asked to find a hidden goal (a WiFi signal) that was located in 1 of the right-angled corners of a kite-shaped (Experiment 1) or a cross-shaped (Experiment 2) virtual environment. Goal location was defined solely with respect to the geometry of the environment. Following this training, in a test conducted in extinction, participants were placed onto the outside of the same environments and asked to locate the WiFi signal. The results of both experiments revealed that participants spent more time searching in regions on the outside of the environments that were closest to where the WiFi signal was located during training. These results are difficult to explain in terms of analyses of spatial navigation and reorientation that emphasize the role of local representational encoding or view matching. Instead, we suggest that these results are better understood in terms of a global representation of the shape of the environment.

Published
2019

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