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Preregistration of Study 3 from “Does Attending to the Nose vs. Eyes Reduce the Cross-Race Recognition Deficit? A Systematic Test”
No full textIn the present research, we will examine whether the own-race bias in face recognition (ORB; Malpass & Kravitz, 1969) can be eliminated by shifting participants’ attention to the lower half of the faces, as shown by Hills and Lewis (2011)
data files for all studies
No full textThis registration is intended to create a permanent repository for the data files used in the manuscript "Seek and ye shall be fine: attitudes towards political perspective-seekers
PPS study S1 (materials)
No full textContained in this registration are the materials for study S1. This study was not pre-registered before data analyses, but interested readers may still want to see the materials used, so we have included them here
Punishment and reward feedback in sequence learning
No full textProject investigating the impact of punishment or reward feedback on learning and retention
Build a Society
No full textIn this study, we are evaluating people's behaviours with respect to upholding democratic principles
Does trauma-focused therapy change trauma memory? - The selective effects of EMDR, IR and IE on involuntary and voluntary memories of an aversive autobiographical event
No full textVivid, involuntary recollections of trauma fragments (i.e., intrusions) are often perceived as the most distressing symptom for patients suffering from Posttraumatic Stress Disorder (PTSD) (Ehlers, Hackmann, & Michael, 2004; Holmes & Mathews, 2010). Targeting these involuntary expressions of trauma memories has therefore been the main focus of trauma-focused psychological interventions. However, in the light of theoretical considerations suggesting that poorly elaborated and contextualized trauma memories are an important factor contributing to the development and maintenance of PTSD symptoms (Brewin, 2014; Brewin, Dalgleish, & Joseph, 1996; Ehlers & Clark, 2000; Foa & Rothbaum, 1998), trauma-focused interventions should not only aim to reduce involuntary, uncontrollable recall of traumatic events, but also preserve or even promote voluntary, controllable recall of memory content (Lau-Zhu, Henson, & Holmes, 2019). Thus, in order to help patients to remember a traumatic event without reliving it, the effects of psychological interventions on trauma memories should be selective. However, up to date the differential effects of scientifically established trauma-focused interventions on involuntary and voluntary recall of traumatic memory content remain largely unknown. While interventions such as exposure therapy, Eye Movement Desensitization and Reprocessing (EMDR) and Imagery Rescripting (IR) have been shown to successfully reduce the involuntary occurrence of (analogue) traumatic memories (Chen, Hu, & Liang, 2015; Foa, Dancu, Hembree, Jaycox, Meadows, & Street, 1999; Hagenaars & Arntz, 2012), systematic research on their selective effects on the distinct memory systems (i.e. involuntary vs. voluntary memory) is scarce (Visser, Lau-Zhu, Henson, & Holmes, 2018).
The few empirical findings on the effects of EMDR, IR and IE on voluntary memory recall are rather inconsistent: With regard to EMDR, some studies found that eye movements as conducted in EMDR impaired voluntary memory retrieval, resulting in stimulus attributes being less accessible in stimulus discrimination tasks (Leer, Engelhard, Lenaert, Struyf, Vervliet, & Hermans, 2017; van den Hout et al., 2013), elevated susceptibility to false memories in memory recognition tasks (Houben, Otgaar, Roelofs, & Merckelbach, 2018; Houben, Otgaar, Roelofs, Smeets, & Merckelbach, 2020) and reductions in self-reported “thought clarity” of autobiographical memories (Maxfield, Melnyk, & Hayman, 2008). However, these findings could not always be replicated (Calvillo & Emami, 2019; Kevin Van Schie & Leer, 2019) and some experimental studies have demonstrated that bilateral eye-movements may in contrast even enhance memory retrieval (e.g., memory accuracy and number of items recalled) (Christman, Garvey, Propper, & Phaneuf, 2003; Parker, Buckley, & Pagnall, 2009). Interestingly, preliminary evidence from experimental studies did not reveal any adverse effects of IR on accuracy or quality of experimentally induced aversive memories (Hagenaars & Arntz, 2012; Siegesleitner, Strohm, Wittekind, Ehring, & Kunze, 2019). Similarly, one study showed that self-reports of childhood traumatic events in borderline personality disorder patients remained consistent after schema therapy (Kremers, Giezen, Does, Dyck, & Spinhoven, 2007), a psychological treatment that includes IR. However, none of the studies was primarily set up to investigate voluntary memory performance. Moreover, many of the above mentioned studies are compromised in that they do not focus on consolidated memories (i.e., Christman et al., 2003, Experiment 1; Hagenaars & Arntz, 2012; Houben et al., 2018; 2020; Leer et al., 2017; van den Hout et al., 2013; Parker et al., 2009), but rather implement the interventions during encoding or consolidation of an induced memory. This limits the generalizability of findings to (re-)consolidated memories which are typically the clinical target of interventions in PTSD. One recent study by Romano et al. (2020) compared the effects of IR, IE and Supportive Counseling (SC) on content changes in narratives of aversive autobiographical memories in social anxiety disorder (SAD). The study results indicate that IR and IE may have distinct effects on voluntary memory recall: While IR facilitated increases only in positive/neutral memory details, in IE, increases in both positive/neutral and negative memory details were observed. Similarly, with regard to exposure therapy, Foa and colleagues (1995) found that the narrative-length of rape memories as well as the percentage of reported negative feelings increased with treatment and Bedard-Gilligan and colleagues (2017) found an increase in the percentage of sensory and emotional details after IE. However, we have no information about how accurate those details recalled after therapy were. Therefore, it remains unclear, whether this increase in reported details also reflects an improvement in accessibility of voluntary memory. Moreover, a recent study investigating the effects of exposure on voluntary memory in PTSD patients showed no reliable changes from pre- to post-treatment with regard to memory fragmentation (Bedard-Gilligan, Zoellner, & Feeny, 2017). Likewise, a review of the mechanisms of change in exposure treatments concluded that there is currently little evidence for voluntary memory reorganization as a central mechanism of exposure therapy (Cooper, Clifton, & Feeny, 2017).
To summarize, these rather diverse findings demonstrate that changing aversive mental images through psychological interventions does not unavoidably lead to changes in voluntary memory quality. They rather suggest that different treatment techniques may selectively affect involuntary and voluntary trauma memory. Nevertheless, the controversy about the possible detrimental effects that psychotherapy may have on the validity of voluntary memory reports (Engelhard, McNally, & van Schie, 2019; Loftus, 2005) is ongoing. Up until today this regularly leads to the credibility of incomplete and incoherent narratives of traumatic events that have been addressed in psychotherapy being doubted in court (Volbert, Steller, & Galow, 2010). While first studies tentatively suggest that trauma-focused interventions like EMDR may indeed reduce memory accuracy (Houben et al., 2018, 2020; but see Calvillo & Emami, 2019; van Schie & Leer, 2019), we know little about whether EMDR, IE and IR also affect memory quality (i.e. changes in memory disorganization, coherence and content) and if so, whether their effects are distinct. Our study therefore aims to translate the insights on selective memory interference from basic science to trauma-focused treatments in order to better understand their effects on different memory types. This could eventually help to inform clinical practice about how to more precisely target relevant (memory) processes individually
European farmers’ risk attitudes – A cross-country replication of Bocquého et al. (2014)
No full textBackground: Risk and uncertainty are at the core of many questions in agricultural economics, and agricultural economists have been interested in estimating farmers’ risk attitudes for several decades (e.g., Binswanger, 1980; Iyver et al., 2020). In particular, risk attitudes are an important modeling input, and they are of broad interest to policy makers and insurance companies. There is a large diversity of approaches to study farmers’ risk attitudes, and this literature is scattered, with few studies systematically investigating differences across countries and farming systems (Iyer et al., 2020). One popular method to study risk attitudes are incentivized gambles and lotteries based on multiple price lists (e.g., Holt and Laury, 2002). These lotteries have been widely applied to investigate farmers’ risk attitudes (see Iyer et al., 2020 for a recent overview of studies). One of the most widely cited studies in this area is that of Bocquého et al. (2014). This study uses the multiple price lists developed by Tanaka et al. (2010) to investigate whether Expected Utility Theory (EUT) or Cumulative Prospect Theory (CPT) better describes farmers’ attitudes towards risk and uncertainty in a sample of French farmers. The authors use structural models to estimate EUT and CPT parameters. They also estimate models that adjust for socio-demographic heterogeneity. They find that farmers are risk-averse in the gain domain under EUT and exhibit loss aversion and overweighting of small probabilities under CPT. This replication proposal focuses on exploring the robustness and boundaries of the estimates of Bocquého et al. (2014). The replication will entail two exercises. First, we have obtained the original data and code from the authors and we will replicate the analysis. This allows us to establish a coherent econometric benchmark to compare the original model results with those obtained by us. Second, we will apply a similar protocol in several European countries and for different farming systems (see list below). Our replication focuses on the same question as the original study: Are farmers’ risk attitudes better described by EUT or by CPT? We also strive to showcase best practices for cross-country data collection in future replication efforts in experimental agricultural economics by embracing open science practices (i.e., follow a pre-registration with power calculations, open data, and open methods).
Method: Our replication will reproduce the same experimental design (focused on the risk task, while the original study also had a longer survey including also an ambiguity and time tasks) but will deviate in some aspects. These deviations are needed, partly for feasibility considerations, but also because we strive to test a simpler protocol capable of yielding results of equivalent quality and robustness. First, the original study investigated 107 farmers from 64 towns in the French Bourgogne region in a 2-hour face-to-face interview. Our data collection will take place online or face-to-face, depending on feasibility in each of the case studies (see details below). In the online surveys, we implement a 2 minutes video explaining the task, as a compensation for a lack of personal interaction. Second, the sample will be more diverse, both in terms of origin and farm type. While French farmers will also be interviewed in the replication (from both South and North West of France), we will also rely on a mix of convenience and random samples of farmers from other European regions across a wide range of farming systems. We want to achieve a comparable statistical power as the original study (assuming the same effect sizes) at country level, i.e., there should be 107 farmers or more for most countries. In total, we expect a substantially larger pooled sample. We will discuss deviations from the original estimates (if any) against the background of amendments in the protocol and the cultural/economic contexts. Third, while every farmer received a payment in the original study, we will incentivize a certain proportion of farmers with a cash payment or a close equivalent (e.g., vouchers for a popular online shopping outlet in the respective country). Fourth, the exchange rate in the experiment will be known to our participants a priori, because the original procedure with an envelope that contains the exchange rate – only revealed after the lotteries – is difficult to mimic online.
The analysis will report the results of the same structural models as the original study (without covariates) and to explore the impact of (other) covariates. Due to the different contexts, we will define a set of covariates that overlap for our various cases in the original study. Similar to the original study, we will employ a series of robustness tests to understand how other reference points than zero might drive results for CPT estimates. The authors have developed a joint survey instrument in Qualtrics in English. For each case study there is an individual survey in English and the local language.
References:
Binswanger, H. P. (1980). Attitudes toward risk: Experimental measurement in rural India. American Journal of Agricultural Economics, 62(3), 395-407.
Bocquého, G., Jacquet, F., & Reynaud, A. (2014). Expected utility or prospect theory maximisers? Assessing farmers' risk behaviour from field-experiment data. European Review of Agricultural Economics, 41(1), 135-172.
Holt, C. A., & Laury, S. K. (2002). Risk aversion and incentive effects. American Economic Review, 92(5), 1644-1655.
Iyer, P., Bozzola, M., Hirsch, S., Meraner, M., & Finger, R. (2020). Measuring farmer risk preferences in Europe: a systematic review. Journal of Agricultural Economics, 71(1), 3-26.
Tanaka, T., Camerer, C. F., & Nguyen, Q. (2010). Risk and time preferences: Linking experimental and household survey data from Vietnam. American Economic Review, 100(1), 557-71
Investigating the stability of lexical entrainment in adulthood
No full textIntroduction
During dialogue, adults tend to imitate their interlocutors’ language use. This conversational alignment occurs at multiple different levels of language and seems to function to ensure effective communication and rewarding interactions. In this study we specifically focus on the tendency for a speaker to reuse the same word as that used by a conversational partner (e.g. using brolly after your partner has used brolly; Brennan & Clark, 1996), known as lexical entrainment.
It is well established that lexical entrainment implicates both unmediated processing (e.g. lexical retrieval) and mediated processing (e.g. speakers’ beliefs about their interlocutor). Unmediated theories have highlighted the role of automatic priming in lexical entrainment, whereby exposure to a partner’s lexical label (e.g. brolly) makes its representation more accessible in memory and easier to retrieve and reuse (Pickering & Garrod, 2004). Moreover, mediated theories have suggested that speakers’ beliefs may also influence their tendency to entrain – they may adapt their use of language based on what they believe a conversational partner will understand (audience design mechanisms; Clark, 1996), or in order to express affiliation and establish rapport (social-affective mechanisms; van Baaren et al., 2003).
Previous studies have examined the mechanisms underlying lexical entrainment using group-level comparisons (e.g. Branigan et al., 2011). However, mediated and unmediated processing mechanisms can also vary as a result of individual differences (Tobar-Henriquez et al., 2019); this thus provides the opportunity to understand how and why lexical entrainment might vary based on individual characteristics such as age and language ability. However, in order to understand the role of individual differences in lexical entrainment, we must first establish whether lexical entrainment is a trait which is stable within individuals. We have previously established this in adults aged 18-60 (Tobar-Henríquez et al., 2020).
Furthermore, a pilot study has suggested that lexical entrainment increases with age, so that older speakers entrain more than younger speakers (Tobar-Henríquez, 2020). This is an important preliminary finding because it suggests that lexical entrainment mechanisms change across adulthood, thus opening new directions to investigate both lexical entrainment mechanisms, in particular, and language processing across the lifespan, in general. Understanding whether and how the effect of age on lexical entrainment correlates with other language-related changes (such as autistic traits and beliefs about one’s own language skills), can cast light on which mechanisms might be driving this effect.
For example, since lexical entrainment is influenced by speakers’ beliefs about their addressees, individuals with deficits in theory of mind, communication and social interaction, or understanding intentionality, might show differences in lexical entrainment. Impairments in these areas are found in individuals with Autism Spectrum Condition (ASC) (DSM-5; American Psychiatric Association, 2013), therefore a negative correlation between autistic traits and lexical entrainment might be expected. However, work to date has found the same magnitude of lexical entrainment in adults and children with ASC as in their neurotypical peers and has not established a relationship between severity of autistic traits and entrainment (Branigan et al., 2016; Hopkins et al., 2017; Slocombe et al., 2013). This pattern is consistent with alignment arising from priming mechanisms that are intact in adults and children with ASC. Importantly, however, preliminary research suggests that when combined with reduced perspective-taking abilities, priming mechanisms may lead children with ASC to be susceptible to maladaptive lexical (over-)entrainment (i.e., entrainment that might lead to miscommunication; Hopkins, 2016; Hopkins et al., 2017; see also evidence for maladaptive (over-)entrainment in neurotypical younger children; Garrod & Clark, 1993). We know that neurotypical older adults show reduced perspective-taking compared to younger adults (Horton & Spieler, 2007), alongside higher levels of lexical entrainment; as such, investigating autistic traits in conjunction with age may be informative in regards to the mechanisms underlying this age effect.
Examining individual differences in older adults’ beliefs about their own language skills is a further avenue through which we may investigate lexical entrainment and language processing mechanisms across the lifespan. Both older adults, and their younger counterparts, report believing that their language skills generally worsen with age, although older and younger adults underestimate and overestimate their language skills respectively (Hummert et al., 1995). We are particularly interested in how such beliefs could influence lexical choices during dialogue. For example, if older people lexically entrain more often than younger people mainly due to a higher interest in being understood correctly (i.e., audience design), then we would expect older adults who have more negative beliefs about their own language skills to entrain more often than older adults who possess more positive beliefs about these skills. In contrast, if older people entrain more often than younger people mainly due to a higher sensitivity to recent lexical processing (i.e., lexical priming), then we would expect that older adults’ propensity to lexically entrain is not significantly influenced by their beliefs about their own language skills.
Better understanding these issues concerning the nature of lexical alignment across the lifespan can provide important insight into inter-generational communication in older adults because effective communication necessitates continuously updating the language one uses to incorporate changes driven by younger speakers, and lexical entrainment could represent a means by which to learn new lexical labels and the correct contexts of use (Tobar-Henríquez et al., 2021).
In the current study, it is important to first confirm that lexical entrainment is stable across the lifespan, including in older adults, before looking at how individual traits might affect lexical entrainment in this population. We therefore first investigate the stability of lexical entrainment in three groups of participants aged 18-39, 40-59 and over 60. Second, we examine the relationship between (1) participants’ autistic traits, and (2) their impressions about their own linguistic skills, on their tendency to lexically entrain with age. In addition to our lexical entrainment instrument, we thus use instruments which are able to consistently distinguish between individuals’ levels of autistic traits and impressions about their own linguistic skills (see ‘The present experiment’ section)
EDA project
No full textOverview
This study will test the calibration of confidence and truth (i.e. under- or overprecision) among subjects who estimate how many dots there are in images containing between 1 and 1000 dots each
