Methods and pitfalls in the study of uncoscious mental process

Many studies of unconscious processing involve comparing a performance measure (e.g., some assessment of perception, memory, etc.) with an awareness measure (such as a verbal report or a forced-choice response) taken either concurrently or separately. Unconscious processing is inferred when above-chance performance is combined with null awareness. Often, however, aggregate awareness is better than chance, and data analysis therefore employs a form of extreme group analysis focusing post hoc on participants, trials, or items where awareness is absent or at chance. The pitfalls of this analytic approach are described with particular reference to recent research on implicit learning and subliminal perception. Because of regression to the mean, the approach can mislead researchers into erroneous conclusions concerning unconscious influences on behaviour.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Underpowered samples, false negatives, and unconscious learning

The scientific community has witnessed growing concern about the high rate of false positives and unreliable results within the psychological literature, but the harmful impact of false negatives has been largely ignored. False negatives are particularly concerning in research areas where demonstrating the absence of an effect is crucial, such as studies of unconscious or implicit processing. Research on implicit processes seeks evidence of above-chance performance on some implicit behavioral measure at the same time as chance-level performance (that is, a null result) on an explicit measure of awareness. A systematic review of 73 studies of contextual cuing, a popular implicit learning paradigm, involving 181 statistical analyses of awareness tests, reveals how underpowered studies can lead to failure to reject a false null hypothesis. Among the studies that reported sufficient information, the meta-analytic effect size across awareness tests was d z = 0.31 (95 % CI 0.24–0.37), showing that participants’ learning in these experiments was conscious. The unusually large number of positive results in this literature cannot be explained by selective publication. Instead, our analyses demonstrate that these tests are typically insensitive and underpowered to detect medium to small, but true, effects in awareness tests. These findings challenge a widespread and theoretically important claim about the extent of unconscious human cognition

Take the best or look at the rest? Factors influencing "one-reason" decision making.

Aspects of an experimental environment were manipulated in 3 experiments to examine the parameters under which the "take-the-best" (TTB) heuristic (e.g., G. Gigerenzer & D. G. Goldstein, 1996) operates. Results indicated TTB use to be more prevalent when the cost of information was high, when validities of the cues were known, and when a deterministic environment was used. However, large individual variability in strategy use was observed as well as a significant proportion of behavior inconsistent with TTB, expecially its stopping rule. The results demarcate some of the heuristic's boundary conditions and also question the validity of TTB as a psychologically plausible and pervasive model of behavior

Decision making

This chapter reviews normative and descriptive aspects of decision making. Expected Utility Theory (EUT), the dominant normative theory of decision making, is often thought to provide a relatively poor description of how people actually make decisions. Prospect Theory has been proposed as a more descriptively valid alternative. The failure of EUT seems at least partly due to the fact that people’s preferences are often unstable and subject to various influences from the method of elicitation, decision context, and goals. In novel situations, people need to infer their preferences from various cues such as the context and their memories and emotions. Through repeated experience with particular decisions and their outcomes, these inferences can become more stable, resulting in behavior that is more consistent with EUT

Heterogeneity and Publication Bias in Research on Test-Potentiated New Learning

Prior retrieval practice potentiates new learning. A recent meta-analysis of this test-potentiated new learning (TPNL) effect by Chan, Meissner, and Davis (2018) concluded that it is a robust and reliable finding (Hedges’ g = 0.44). Although Chan et al. discussed three different experimental designs that have been employed to study TPNL, we argue that their meta-analysis failed to adequately distinguish the findings from these different designs, acknowledge the significance of the substantial between-study heterogeneity across all pooled effects, and assess the degree of publication bias in the sample. We conducted a new meta-analysis that assessed the designs separately and applied appropriate corrections for publication bias. We found that studies using a standard design yield weak evidence of a TPNL effect, studies using pre-testing yield a small but reliable effect, and studies using interleaving designs yield weak evidence of a negative effect. Compared to Chan et al.’s conclusions, these reanalyses cast TPNL in a very different light and point to a pressing need for preregistered experiments to assess its reproducibility in the absence of publication bias

Conscious and unconscious memory and eye movements in context-guided visual search: A computational and experimental reassessment of Ramey, Yonelinas, and Henderson (2019)

Are eye movements unconsciously guided towards target locations in familiar scenes? In a recent eyetracking study, Ramey, Yonelinas, and Henderson (2019) measured eye-movement efficiency (scanpath ratio) and memory judgments when participants searched for targets in repeated and novel scenes. When trials judged new with high confidence were selected, scanpath ratio was lower for old scenes (misses) than for new scenes (correct rejections). In addition, familiarity as measured by recognition confidence did not significantly predict scanpath ratio. Ramey et al. attributed these results to unconscious learning guiding eye movements. In a re-assessment of Ramey et al.’s data, we show that their findings can be accounted for by a single-system computational model in which eye movements and memory judgments are driven by a common latent memory representation. In particular, (a) the scanpath ratio difference between high-confidence misses and correct rejections is a consequence of regression to the mean, while (b) the null correlation between familiarity and scanpath ratio, partly a natural consequence of the low reliability of the scanpath ratio measure, is also reproduced by the model. Two pre-registered experiments confirm a novel prediction of the alternative single-system model. This work offers a parsimonious account of Ramey et al.’s findings without recourse to unconscious guidance of eye movements

The Pervasive Problem of Post Hoc Data Selection in Studies on Unconscious Processing

Studies on unconscious mental processes typically require that participants are unaware of some information (e.g., a visual stimulus). An important methodological question in this field of research is how to deal with data from participants who become aware of the critical stimulus according to some measure of awareness. While it has previously been argued that the post hoc selection of participants dependent on an awareness measure may often result in regression-to-the-mean artifacts (Shanks, 2017), a recent article (Sklar et al., 2021) challenged this conclusion claiming that the consideration of this statistical artifact might lead to unjustified rejections of true unconscious influences. In this reply, we explain this pervasive statistical problem with a basic and concrete example, show that Sklar et al. fundamentally mischaracterize it, and then refute the argument that the influence of the artifact has previously been overestimated. We conclude that, without safeguards, the method of post hoc data selection should never be employed in studies on unconscious processing

Is probabilistic cuing of visual search an inflexible attentional habit? A meta-analytic review

In studies on probabilistic cuing of visual search, participants search for a target among several distractors and report some feature of the target. In a biased stage the target appears more frequently in one specific area of the search display. Eventually, participants become faster at finding the target in that rich region compared to the sparse region. In some experiments, this stage is followed by an unbiased stage, where the target is evenly located across all regions of the display. Despite this change in the spatial distribution of targets, search speed usually remains faster when the target is located in the previously rich region. The persistence of the bias even when it is no longer advantageous has been taken as evidence that this phenomenon is an attentional habit. The aim of this meta-analysis was to test whether the magnitude of probabilistic cuing decreases from the biased to the unbiased stage. A meta-analysis of 42 studies confirmed that probabilistic cuing during the unbiased stage was roughly half the size of cuing during the biased stage, and this decrease persisted even after correcting for publication bias. Thus, the evidence supporting the claim that probabilistic cuing is an attentional habit might not be as compelling as previously thoughtOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study was supported by grants 2016-T1/SOC-1395, 2017-T1/SOC-5147, and 2020-5A/SOC-19723 from Comunidad de Madrid, Spain (Programa de Atracción de Talento Investigador), grants PSI2017-85159-P, PGC2018-094694-B-I00, and PID2020-118583GB-I00 from Agencia Estatal de Investigación, Spain, and FEDER, EU, and grant ES/S014616/1 from the Economic and Social Research Council, United Kingdo

Do partial and distributed tests enhance new learning?

Testing facilitates subsequent learning of new information, a phenomenon known as the forward testing effect. The effect is often investigated in multilist procedures, where studied lists are followed by a retrieval test, or a control task such as restudying, and learning is compared on the final list. In most studies of the effect, tests include all material from the preceding list. We report four experiments, three of which were preregistered, to determine whether tests that are partial (not including all studied items) and distributed (including retrieval of items from earlier lists) are effective in enhancing new learning. The results show that testing of all studied material is not necessary to produce beneficial effects on new learning or to reduce intrusions. The beneficial effects of testing were substantially mediated by reduced proactive interference. Importantly, there was minimal evidence that the forward learning benefits of partial and distributed tests are offset by a cost to untested items via retrieval-induced forgetting