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1.
Chemistry ; 28(69): e202202660, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36098179

RESUMO

The metalation of N,N-dimethylaminomethylferrocene in THF by the superbasic mixture of n BuLi/KOt Bu proceeds readily at low temperatures to afford a bimetallic Li2 K2 aggregate containing ferrocenyl anions and tert-butoxide. Starting from an enantiomerically enriched ortho-lithiated aminomethylferrocene, an enantiomerically pure superbase can be prepared. The molecular compound exhibits superbasic behavior deprotonating N,N-dimethylbenzylamine in the α-position and is also capable of deprotonating toluene. Quantum chemical calculations provide insight into the role of the bridging THF molecule to the possible substrate-reagent interaction. In addition, a benzylpotassium alkoxide adduct gives a closer look into the corresponding reaction site of the Lochmann-Schlosser base that is reported herein.


Assuntos
Compostos Organometálicos , Indicadores e Reagentes , Compostos Organometálicos/química , Lítio/química , Tolueno , Ânions
2.
Psychol Sci ; 32(1): 120-131, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33301363

RESUMO

Evaluative conditioning is one of the most widely studied procedures for establishing and changing attitudes. The surveillance task is a highly cited evaluative-conditioning paradigm and one that is claimed to generate attitudes without awareness. The potential for evaluative-conditioning effects to occur without awareness continues to fuel conceptual, theoretical, and applied developments. Yet few published studies have used this task, and most are characterized by small samples and small effect sizes. We conducted a high-powered (N = 1,478 adult participants), preregistered close replication of the original surveillance-task study (Olson & Fazio, 2001). We obtained evidence for a small evaluative-conditioning effect when "aware" participants were excluded using the original criterion-therefore replicating the original effect. However, no such effect emerged when three other awareness criteria were used. We suggest that there is a need for caution when using evidence from the surveillance-task effect to make theoretical and practical claims about "unaware" evaluative-conditioning effects.


Assuntos
Conscientização , Condicionamento Psicológico , Adulto , Atitude , Condicionamento Clássico , Humanos , Processos Mentais
3.
Chemistry ; 27(71): 17780-17784, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34633717

RESUMO

The incorporation of heavy alkali metals into substrates is both challenging and essential for many reactions. Here, we report the formation of THF-solvated alkali metal benzyl compounds [PhCH2 M ⋅ (thf)n ] (M=Na, Rb, Cs). The synthesis was carried out by deprotonation of toluene with the bimetallic mixture n-butyllithium/alkali metal tert-butoxide and selective crystallization from THF of the defined benzyl compounds. Insights into the molecular structure in the solid as well as in solution state are gained by single crystal X-ray experiments and NMR spectroscopic studies. The compounds could be successfully used as alkali metal mediating reagents. The example of caesium showed the convenient use by deprotonating acidic C-H as well as N-H compounds to gain insight into the aminometalation using these reagents.

4.
Conscious Cogn ; 96: 103238, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34784558

RESUMO

Fluency is the experienced ease of ongoing mental operations, which increases the subjective positivity of stimuli attributes. This may happen because fluency is inherently positive. Alternatively, people may learn the meaning of fluency from contingencies within judgment-contexts. We test pseudocontingencies (PCs) as a mechanism through which fluency's meaning is learned. PCs are inferred correlations between two attributes due to the observation of their jointly skewed base rates - people relate what is frequent in one attribute to what is frequent in the other. Using online seller evaluations as the dependent variable, we manipulated base rates of seller name-fluency and seller reputation, creating conditions where name-fluency aligned positively or negatively with reputation. However, participants evaluated high-fluency name sellers more positively across base-rate conditions, although we observed negative PCs between seller reputation and a fluency-neutral dimension in a follow-up study. We discuss the implications for the debate regarding fluency's positive vs. malleable nature.


Assuntos
Julgamento , Seguimentos , Humanos
5.
Mem Cognit ; 49(4): 843-862, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33349898

RESUMO

When people answer the question "How many animals of each kind did Moses take on the Ark?", they usually respond with "two," although Moses does not appear in the biblical story of the Ark. We investigated this "Moses illusion" in a multiple-choice format and tested the influence of monetary incentives on the illusion's strength. Thereby, we addressed the role of a cooperative communication context for the illusion's emergence, as well as the role of participants' motivation. In four experiments (total N = 914), we found that the Moses illusion persists in a multiple-choice format. As the multiple-choice format realizes a cooperative context in which the correct answer is always available, we exclude a cooperative context explanation for the illusion. Monetary incentives reduced the strength of the illusion. However, the reduction was numerically and statistically small. We thereby show that the illusion is not due to violations of cooperative communications, and not due to a lack of motivation. The multiple-choice approach will facilitate further research on the Moses illusion and the data provide additional evidence for the Moses illusion's empirical robustness and constrain its theoretical explanations.


Assuntos
Ilusões , Motivação , Humanos
6.
Cogn Emot ; 34(1): 105-127, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31020918

RESUMO

Generalisation in learning means that learning with one particular stimulus influences responding to other novel stimuli. Such generalisation effects have largely been overlooked within research on attitude acquisition via Evaluative Conditioning (i.e. EC effects). In five experiments, we investigated whether and when generalisation of EC effects is based on similarity or on abstract rules. Experiments 1, 2a, 2b and 3 showed that participants who abstracted a rule during the learning phase used that rule for category judgments of novel stimuli. However, evaluative ratings of the same stimuli were unaffected by the learned rule but followed the similarity to learned stimuli. Experiment 4 showed that this similarity-based pattern of generalisation is not specific to evaluative ratings. Rather, resemblance between judgment task and learning task seems to determine whether acquired rules are taken into account. We discuss how dual-process and single-process models of EC may account for the obtained generalisation results.


Assuntos
Atitude , Generalização Psicológica , Julgamento , Aprendizagem , Feminino , Humanos , Masculino , Modelos Psicológicos , Adulto Jovem
7.
Angew Chem Int Ed Engl ; 59(50): 22500-22504, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-32846026

RESUMO

Insights gained from a comparison of aminometalation reactions with lithium amides, potassium amides and mixed lithium/potassium amides are presented. A combination of structural characterization, DFT calculations and electrophile reactions of aminometalated intermediates has shown the advantages of using a mixed metal strategy. While potassium amides fail to add, the lithium amides are uncontrollable and eliminated, yet the mixed K/Li amides deliver the best of both systems. Aminopotassiation proceeds to form the alkylpotassium species which has enhanced stability over its lithium counterpart allowing for its isolation and thereby its further characterization.

8.
Cogn Emot ; 33(6): 1224-1238, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30475089

RESUMO

People judge positive information to be more alike than negative information. This good-bad asymmetry in similarity was argued to constitute a true property of the information ecology (Alves, H., Koch, A., & Unkelbach, C. (2017). Why good is more alike than bad: Processing implications. Trends in Cognitive Sciences, 21, 69-79). Alternatively, the asymmetry may constitute a processing outcome itself, namely an influence of phasic affect on information processing. Because no research has yet tested whether phasic affect influences perceived similarity among stimuli, we conducted 5 Experiments that also tested whether phasic affect can account for the higher judged similarity among positive compared to negative stimuli. In three experiments, we affectively charged pictures of different Pokemon by pairing them with monetary gains and losses (Exp. 1a, 1b) as well as positive and negative trait words (Exp. 2); yet, the evaluative charge did not differentially influence perceived similarity among the Pokemon. Experiment 3 replicated the basic similarity asymmetry among positive and negative words, and found that it was unaffected by externally induced phasic affect. Experiment 4 showed that phasic affect had no influence on perceived similarity of non-evaluative words either. We conclude that albeit a weak influence of phasic affect on perceived similarity of stimuli cannot be ruled out entirely, it can most likely not account for the typically medium to large sized asymmetry in similarity among positive and negative stimuli.


Assuntos
Afeto/fisiologia , Julgamento/fisiologia , Adulto , Feminino , Alemanha , Humanos , Masculino , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Adulto Jovem
9.
Psychol Sci ; 29(7): 1126-1133, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29746235

RESUMO

People often hold negative attitudes toward out-groups and minority groups. We argue that such intergroup biases may result from an interaction of basic cognitive processes and the structure of the information ecology. This cognitive-ecological model assumes that groups such as minorities and out-groups are often novel to a perceiver. At the level of cognition, novel groups are primarily associated with their unique attributes, that is, attributes that differentiate them from other groups. In the information ecology, however, unique attributes are likely to be negative. Thus, novel groups, and by proxy minorities and out-groups, tend to be associated with negative attributes, leading to an evaluative disadvantage. We demonstrated this disadvantage in three experiments in which participants successively formed impressions about two fictional groups associated with the same number of positive and negative attributes. Participants preferred the first group over the novel group as long as the groups' unique attributes were negative.


Assuntos
Comportamento de Escolha/fisiologia , Processos Grupais , Preconceito , Percepção Social , Estereotipagem , Adulto , Humanos
10.
Angew Chem Int Ed Engl ; 56(45): 14164-14168, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-28940968

RESUMO

Described herein is a selective way to control the reaction of allylic amines with metalorganic bases depending on the amine handle as well as the metalorganic base is used. Depending on the number of coordinating groups within the amine handle either a selective carbometalation or deprotonation reaction can be performed. By changing the alkali metal within the base from lithium to either sodium or potassium, a change of chemoselectivity takes place and the reaction of piperidinoallylamine can be controlled.

11.
Mem Cognit ; 43(6): 896-909, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25772462

RESUMO

The density hypothesis states that positive information is more similar than negative information, resulting in higher density of positive information in mental representations. The present research applies the density hypothesis to recognition memory to explain apparent valence asymmetries in recognition memory, namely, a recognition advantage for negative information. Previous research explained this negativity advantage on the basis of valence-induced affect. We predicted that positive information's higher density impairs recognition performance. Two old-new word recognition experiments tested whether differential density between positive and negative stimuli creates a negativity advantage in recognition memory, over and above valence-induced affect. In Experiment 1, participants better discriminated negative word stimuli (i.e., less false alarms) and showed a response bias towards positive words. Regression analyses showed the asymmetry to be function of density and not of valence. Experiment 2 varied stimulus density orthogonal to valence. Again, discriminability and response bias were a function of density and not of valence. We conclude that the higher density of positive information causes an apparent valence asymmetry in recognition memory.


Assuntos
Afeto/fisiologia , Idioma , Reconhecimento Psicológico/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
12.
Angew Chem Int Ed Engl ; 53(2): 553-6, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24273149

RESUMO

The metalation of benzene by Schlosser's base (nBuLi/tBuOK) occurs smoothly in THF at low temperatures to afford a discrete mixed-metal Li2 K4 cluster that contains phenyl anions and tert-butoxide. The aggregate itself exhibits superbasic behavior by metalating toluene. The delocalized benzyl anion obtained this way π bonds to potassium counterions, thereby creating a 2D coordination polymer.


Assuntos
Benzeno/química , Lítio/química , Compostos Organometálicos/síntese química , Potássio/química , Tolueno/química , terc-Butil Álcool/química , Furanos/química , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/química
13.
Cognition ; 247: 105791, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593568

RESUMO

Repeating information increases people's belief that the repeated information is true. This truth effect has been widely researched and is relevant for topics such as fake news and misinformation. Another effect of repetition, which is also relevant to those topics, has not been extensively studied so far: Do people believe they knew something before it was repeated? We used a standard truth effect paradigm in four pre-registered experiments (total N = 773), including a presentation and judgment phase. However, instead of "true"/"false" judgments, participants indicated whether they knew a given trivia statement before participating in the experiment. Across all experiments, participants judged repeated information as "known" more often than novel information. Participants even judged repeated false information to know it to be false. In addition, participants also generated sources of their knowledge. The inability to distinguish recent information from well-established knowledge in memory adds an explanation for the persistence and strength of repetition effects on truth. The truth effect might be so robust because people believe to know the repeatedly presented information as a matter of fact.

14.
Pers Soc Psychol Bull ; : 1461672241235387, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551072

RESUMO

We investigate how the complexity of the social environment (more vs. less groups) influences attitude formation. We hypothesize that facing a larger number of groups renders learning processes about these groups noisier and more regressive, which has two important implications. First, more-complex social environments should lead perceivers to underestimate actual group differences. Second, because most people usually behave positively, more-complex social environments produce negatively biased attitudes and cause perceivers to overestimate the frequency of "negative" individuals among groups. We tested these predictions in five attitude formation experiments (N=2,414). Participants' attitudes and learned base rates of positive and negative group members proved more regressive in complex social environments, that is, with multiple groups, compared with less-complex environments, that is, with fewer groups. In a predominantly positive social environment, this regression caused participants to form more negative group attitudes and more strongly overestimate negative individuals' prevalence among groups.

15.
J Exp Psychol Appl ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386405

RESUMO

Attribute conditioning refers to the phenomenon that target stimuli acquire specific attributes by pairing them with stimuli possessing these attributes. We apply attribute conditioning to a marketing context where brands are often displayed with stimuli possessing semantic attributes to establish brand-attribute associations. In particular, we examine whether it is more effective from a brand image perspective to associate a brand with only one attribute, two related attributes, or two unrelated attributes. Across four experimental studies, we find that pairing a single attribute (e.g., athletic) with a brand is most effective for building brand-attribute associations and that pairing multiple, related attributes (athletic and healthy) is more effective than pairing multiple, unrelated attributes (athletic and smart). Supplementing this finding, an analysis of observational data from real brands suggests that attributing two orthogonal attributes to a brand is associated with negative effects on marketing-relevant outcomes. Our findings extend previous research on multiattribute conditioning and highlight the importance of the number and relationship between attributes for building effective brand associations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

16.
Cognition ; 242: 105651, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37871412

RESUMO

People judge repeated statements as more truthful than new statements: a truth effect. In three pre-registered experiments (N = 463), we examined whether people expect repetition to influence truth judgments more for others than for themselves: a bias blind spot in the truth effect. In Experiments 1 and 2, using moderately plausible and implausible statements, respectively, the test for the bias blind spot did not pass the significance threshold set for a two-step sequential analysis. Experiment 3 considered moderately plausible statements but with a larger sample of participants. Additionally, it compared actual performance after a two-day delay with participants' predictions for themselves and others. This time, we found clear evidence for a bias blind spot in the truth effect. Experiment 3 also showed that participants underestimated the magnitude of the truth effect, especially so for themselves, and that predictions and actual truth effect scores were not significantly related. Finally, an integrative analysis focusing on a more conservative between-participant approach found clear frequentist and Bayesian evidence for a bias blind spot. Overall, the results indicate that people (1) hold beliefs about the effect of repetition on truth judgments, (2) believe that this effect is larger for others than for themselves, (3) and underestimate the effect's magnitude, and (4) particularly so for themselves.


Assuntos
Julgamento , Humanos , Teorema de Bayes , Viés
17.
J Exp Psychol Learn Mem Cogn ; 49(8): 1264-1279, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36006728

RESUMO

Past research indicates that people judge repeated statements as more true than new ones. An experiential consequence of repetition that may underly this "truth effect" is processing fluency: Processing statements feels easier following their repetition. In three preregistered experiments (N = 684), we examined the effect of merely instructed repetition (i.e., not experienced) on truth judgments. Experiments 1-2 instructed participants that some statements were present (vs. absent) in an exposure phase allegedly undergone by other individuals. We then asked them to rate such statements based on how they thought those individuals would have done. Overall, participants rated repeated statements as more true than new statements. The instruction-based repetition effects were significant but also significantly weaker than those elicited by the experience of repetition (Experiments 1 and 2). Additionally, Experiment 2 clarified that adding a repetition status tag in the experienced repetition condition did not impact truth judgments. Experiment 3 further showed that the instruction-based effect was still detectable when participants provided truth judgments for themselves rather than estimating other people's judgments. We discuss the mechanisms that can explain these effects and their implications for advancing our understanding of the truth effect. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Emoções , Julgamento , Humanos
18.
J Pers Soc Psychol ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38032665

RESUMO

We investigate self-appraisals over time using a cognitive-ecological approach. We assume that ecologically, negative person attributes are more diverse than positive ones, while positive person attributes are more frequent than negative ones. We combine these ecological properties with the cognitive process of similarity- and differences-based social comparisons to predict temporal self-appraisals. The resulting cognitive-ecological model predicts that people should evaluate similarities with themselves over time positively, whereas differences would be evaluated more negatively. However, because positive attributes are reinforced over time relative to negative attributes, we predicted an asymmetry to emerge such that distinct attributes of the past self (past differences) would be most negative. Six experiments (total N = 1,796) and an integrative data analysis confirmed the cognitive-ecological model's predictions for temporal self-appraisals. However, we found no evidence for motivated self-perception across time. We discuss the implications of these findings for temporal self-appraisal theory and other aspects of self and identity. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

19.
Cogn Emot ; 26(3): 534-40, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21770728

RESUMO

Evaluative conditioning (EC) refers to valence changes of initially neutral stimuli (CSs) through repeated pairings with positive or negative stimuli (USs). The current study is about the moderating role of qualifiers that specify the CS-US relation during these pairings. We show successful EC with pictures of men (CSs) and of liked/disliked animals or landscapes (USs). More importantly, the same pairings resulted in standard and reversed EC effects depending on semantic qualifier of the CS-US relation. CSs loving positive (negative) USs became more positive (negative), while CSs loathing positive (negative) USs became more negative (positive). These data favour a propositional EC account (De Houwer, 2009) over a purely associative account, as they show that it is not only relevant that CS and US are related, but how they are related.


Assuntos
Aprendizagem por Associação , Condicionamento Clássico , Ódio , Amor , Sinais (Psicologia) , Humanos , Masculino , Estimulação Luminosa/métodos
20.
Psychon Bull Rev ; 29(3): 1045-1052, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34918280

RESUMO

People rate and judge repeated information more true than novel information. This truth-by-repetition effect is of relevance for explaining belief in fake news, conspiracy theories, or misinformation effects. To ascertain whether increased motivation could reduce this effect, we tested the influence of monetary incentives on participants' truth judgments. We used a standard truth paradigm, consisting of a presentation and judgment phase with factually true and false information, and incentivized every truth judgment. Monetary incentives may influence truth judgments in two ways. First, participants may rely more on relevant knowledge, leading to better discrimination between true and false statements. Second, participants may rely less on repetition, leading to a lower bias to respond "true." We tested these predictions in a preregistered and high-powered experiment. However, incentives did not influence the percentage of "true" judgments or correct responses in general, despite participants' longer response times in the incentivized conditions and evidence for knowledge about the statements. Our findings show that even monetary consequences do not protect against the truth-by-repetition effect, further substantiating its robustness and relevance and highlighting its potential hazardous effects when used in purposeful misinformation.


Assuntos
Julgamento , Motivação , Comunicação , Humanos , Julgamento/fisiologia , Conhecimento , Tempo de Reação
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