Children''s understanding of belief and disconfirming visual evidence

Data from 3- to 5-year-old children show that even the youngest have an understanding that a story character cannot think an object is in a box when the character looks into the empty box. This understanding is, however, limited to the case where children share the same visual perspective with the character. When visual perspectives are different the relevant knowledge develops shortly after 4 years at about the time that children master the false belief task. These results are interpreted as young children using an implicit constraint that “think” cannot be applied in view of disconfirming visual evidence. This implicit knowledge becomes explicit and, thus, perspective independent with some delay.     

Countering conspiracy theory beliefs: Understanding the conjunction fallacy and considering disconfirming evidence

Research suggests that a number of cognitive processes—including pattern perception, intentionality bias, proportionality bias, and confirmation bias—may underlie belief in a conspiracy theory. However, there are reasons to believe that conspiracy theory beliefs also depend in part on a failure to understand the probability of actual events allegedly supporting those conspiracy theories as well as a failure to entertain disconfirming evidence that may contradict those beliefs. Study 1 examines the relationships between general beliefs in conspiracy theories, belief in a novel conspiracy theory, conjunctive error propensity, and the propensity to consider disconfirming evidence. Study 2 investigates the roles of confronting both the propensity to make conjunctive errors and the failure to consider disconfirming evidence in changing conspiracy theory beliefs as well as attitudes associated with those beliefs. The results of both studies suggest that corrections to one's propensity to make conjunctive errors and mindful consideration of disconfirming evidence may serve as viable methods of self-persuasion pertaining to conspiracy theory beliefs.     

Expectation-based and data-based illusory correlation: the effects of confirming versus disconfirming evidence

The present study (n=154) examines the effects of expectations and stimulus information on the perception of illusory correlation. There have been few studies attempting to integrate expectation-based and data- (distinctiveness-) based processes. These studies suggest that data-based illusory correlation can be overruled by prior expectations, but it is not clear whether this is a consequence of a confirmation bias. In the present study, where participants were not exposed to the specific stimulus information, expectation was manipulated by stating that group B behaved more negatively than group A. Moreover, participants were provided with information contained in a statement-rating task that allowed for the confirmation and disconfirmation of the prior expectations. Participants rated the desirability of these behaviours and also performed the standard illusory correlation tasks. Based on self-categorization theory and Alloy and Tabachnik (1984), we predicted that in the absence of prior expectations, completing the rating task before the illusory correlation tasks would produce stronger illusory correlation than the reverse order. However, in the presence of prior expectations we expected the rating task to undermine illusory correlation, because the information obtained in this task tends to disconfirm prior expectations. Results support the predicted interaction between task order and expectation. We discuss some implications for research on confirmation bias.     

Valerian as a hypnotic for Hispanic patients

Valerian is a botanical used for its sedative effects whose central nervous system activity is ascribed to multiple constituents. Twenty-three established outpatient symptomatic Hispanic volunteers receiving mental health services at a large urban hospital participated in this case study. All complained of insufficient sleep. They were asked to try a popular national brand of valerian ("Nature's Way", 470 mg valerian root) and completed sleep questionnaires at baseline and at the end of Weeks 1 and 2. They were instructed to take 1 capsule each night before retiring and were allowed to increase their dose to a maximum of 3 capsules after Week 1. Twenty patients completed the trial. On an ordinal scale of 1 (no effect), 3 (moderately helpful), and 5 (extremely helpful), 16 patients rated their insomnia as at least "moderately improved" at the end of Week 1. By Week 2, 16 still rated themselves at least "moderately improved," but 15 of them now described their response as either a 4 or a 5. Global improvement at Week 2 was significantly better than at Week 1 (Wilcoxon ranks test p = .005), perhaps reflecting a time-dependent or dose-response relationship. This case study suggests that valerian can be a supplement for improving insomnia in a symptomatic population.     

An investigation of immune system disorder as a "marker" for anomalous dominance

Geschwind and Galaburda (1987) proposed that immune disorder (ID) susceptibility, along with left handedness and familial sinistrality (FS), is a "marker" for anomalous dominance. The theory predicts lesser left lateralization for language processes, lessened left hemisphere abilities, and enhanced right hemisphere abilities. We assessed language laterality (dichotic consonant vowel task) and performances on spatial and verbal tasks. Subjects were 128 college students. The factors of handedness, sex, FS, and immune disorder history (negative or positive) were perfectly counterbalanced. Left-handers were significantly less lateralized for language and scored lower than right-handers on the spatial tasks. Females scored lower on mental rotation than males, but performed comparably to males on the spatial relations task. The only effect of ID was by way of interaction with FS on both spatial tasks--subjects who were either negative or positive on both FS and ID status factors scored significantly higher than subjects negative for one but positive for the other factor. A speculative explanatory model for this interaction was proposed. The model incorporates the notion that FS and ID factors are comparably correlated, but in opposite directions, with hormonal factors implicated by other research as relevant for spatial ability differences. Finally, no support for the "anomalous dominance" hypothesis predictions was found.     

Expectancy confirmation in spite of disconfirming evidence: The case of price increases due to the introduction of the Euro

People in Germany overwhelmingly believe that the Euro introduction caused an overall price increase, however, no such increase actually took place. To investigate whether this disparity could be based on biased perceptions of the average price trend, four studies were conducted. Participants received two menus from a restaurant (one ‘old’ menu with German Mark (DM) prices and one ‘new’ menu with Euro prices) and were asked to estimate the price trend (in per cent). In all of these studies, price trend judgements were biased towards rising prices. If the prices had in fact been raised, the magnitude of this price increase was overestimated. If the prices had remained stable, significant price increases were perceived. And if the prices had fallen, they were perceived as having remained stable. The bias was systematically related to participants' expectations concerning price increases. A ‘selective outcome correction’ hypothesis proved to best fit the data: incorrect calculation outcomes that are in line with one's expectations are overlooked, whereas incorrect inconsistent outcomes are detected and corrected. The results imply that expectations can influence judgements even when clear disconfirming evidence is available that can be compared with an objective standard, thus leaving no room for interpretation. Copyright © 2004 John Wiley & Sons, Ltd.     

Altered and asymmetric default mode network activity in a "hypnotic virtuoso": an fMRI and EEG study

Very highly hypnotizable subjects are rare, easily induced, and able to manifest the whole spectrum of hypnotic phenomena, including post-hypnotic amnesia. The aim of this study was to detect and localize by means of quantitative functional MRI and EEG changes in cortical activity during hypnosis induction and deep "pure hypnosis" in a hypnotic "virtuoso" subject. We focused on areas forming the default mode network (DMN), since previous studies found that very highly suggestible subjects in hypnosis showed decreased activity in anterior DMN. During undisturbed hypnosis, our "virtuoso" subject showed not only detectable changes in DMN, but also peculiar activations of non-DMN areas and hemispheric asymmetries of frontal lobe connectivity. Our findings confirm that hypnosis is associated with significant modulation of connectivity and activity which involve the DMN but are not limited to it, depending on the depth of the hypnotic state, the type of mental content and emotional involvement.     

Distinctiveness as a marker of identity formation

Individual distinctiveness is theorized to characterize an adaptive identity, but its importance remained underexplored. In two studies, we investigated the nomological networks of two common conceptualizations of distinctiveness: general and comparative distinctiveness. We compared these to the network of identity formation’s best-validated marker: commitment. Findings from two samples of young adults living in the Netherlands (n = 320) and in the US (n = 246) both revealed that general distinctiveness marked adaptive identity formation and greater psychosocial well-being. Moreover, general distinctiveness had unique predictive value over commitment strength. Comparative distinctiveness from important others uniquely indicated lowered social well-being. Our findings illustrate that careful attention should be paid to the conceptualization of distinctiveness, because distinctiveness is an important but complex concept.     

Dissociated control as a signature of typological variability in high hypnotic suggestibility

This study tested the prediction that dissociative tendencies modulate the impact of a hypnotic induction on cognitive control in different subtypes of highly suggestible individuals. Low suggestible (LS), low dissociative highly suggestible (LDHS), and high dissociative highly suggestible (HDHS) participants completed the Stroop color-naming task in control and hypnosis conditions. The magnitude of conflict adaptation (faster response times on incongruent trials preceded by an incongruent trial than those preceded by a congruent trial) was used as a measure of cognitive control. LS and LDHS participants displayed marginally superior up-regulation of cognitive control following a hypnotic induction, whereas HDHS participants’ performance declined. These findings indicate that dissociative tendencies modulate the influence of a hypnotic induction on cognitive control in high hypnotic suggestibility and suggest that HS individuals are comprised of distinct subtypes with dissimilar cognitive profiles.