Separating response‐execution bias from decision bias: Arguments for an additional parameter in Ratcliff's diffusion model

Diffusion model data analysis permits the disentangling of different processes underlying the effects of experimental manipulations. Estimates can be provided for the speed of information accumulation, for the amount of information used to draw conclusions, and for a decision bias. One parameter describes the duration of non‐decisional processes including the duration of motor‐response execution. In the default diffusion model, it is implicitly assumed that both responses are executed with the same speed. In some applications of the diffusion model, this assumption will be violated. This will lead to biased parameter estimates. Consequently, we suggest accounting explicitly for differences in the speed of response execution for both responses. Results from a simulation study illustrate that parameter estimates from the default model are biased if the speed of response execution differs between responses. A second simulation study shows that large trial numbers (N>1,000) are needed to detect whether differences in response‐execution times are based on different execution times.     

The effect of multiple indicators on the power to detect inter‐individual differences in change

Hertzog et al. evaluated the statistical power of linear latent growth curve models (LGCMs) to detect individual differences in change, i.e., variances of latent slopes, as a function of sample size, number of longitudinal measurement occasions, and growth curve reliability. We extend this work by investigating the effect of the number of indicators per measurement occasion on power. We analytically demonstrate that the positive effect of multiple indicators on statistical power is inversely related to the relative magnitude of occasion‐specific latent residual variance and is independent of the specific model that constitutes the observed variables, in particular of other parameters in the LGCM. When designing a study, researchers have to consider trade‐offs of costs and benefits of different design features. We demonstrate how knowledge about power equivalent transformations between indicator measurement designs allows researchers to identify the most cost‐efficient research design for detecting parameters of interest. Finally, we integrate different formal results to exhibit the trade‐off between the number of measurement occasions and number of indicators per occasion for constant power in LGCMs.     

Face scanning distinguishes social from communication impairments in autism

How closely related are the social and communicative impairments in Autism Spectrum Disorder (ASD)? Recent findings in typically developing children suggest that both types of impairment are highly heritable but have only moderate behavioural and genetic overlap. So far, their respective roles in social perception are poorly understood. Here we show that when looking at other people’s faces, children with ASD who are better at socio‐emotional behaviours than non‐verbal communication look more at the eyes, while those with the opposite profile look more at the mouth (Study 1). For the mouth area, a similar pattern was observed for inverted faces, suggesting that information from this area is perceived on a featural basis. In Study 2, we found that when shown a person performing manual actions, ‘eye‐lookers’ from Study 1 tended to look most at the face of the actor, while ‘mouth‐lookers’ from Study 1 tended to look at the action itself (hand/objects). This result was found in both ASD and typical development. In Study 3, the main finding in Study 1 was replicated in a new sample. Taken together, we interpret these results as supporting the view that the neural systems underlying socio‐emotional versus non‐verbal communication skills are separable, a finding that has important theoretical and clinical implications. The results also suggest that a similar differentiation of looking behaviour may operate in normal development.     

It just felt right: The neural correlates of the fluency heuristic

Simple heuristics exploit basic human abilities, such as recognition memory, to make decisions based on sparse information. Based on the relative speed of recognizing two objects, the fluency heuristic infers that the one recognized more quickly has the higher value with respect to the criterion of interest. Behavioral data show that reliance on retrieval fluency enables quick inferences. Our goal with the present functional magnetic resonance imaging study was to isolate fluency-heuristic-based judgments to map the use of fluency onto specific brain areas that might give a better understanding of the heuristic’s underlying processes. Activation within the claustrum for fluency heuristic decisions was found. Given that claustrum activation is thought to reflect the integration of perceptual and memory elements into a conscious gestalt, we suggest this activation correlates with the experience of fluency.     

Parenting behaviour as a mediator between young children's negative emotionality and their anxiety/depression

The goal of this longitudinal study was to examine observed paternal and maternal control (psychological control and autonomy granting) and support (rejection and emotional warmth) as mediators of the relation between children's negative emotionality at 3.5 years of age and depression and anxiety problems at 4.5 years. For 35 children, 60‐min unstructured parent–child interactions were rated at 4.5 years. Results indicated that maternal rejection mediated the relation between children's negative emotionality and their later anxiety/depression. Higher levels of child negative emotionality predicted more psychological control in mothers, but did not predict any parenting behaviours in fathers. Higher levels of paternal autonomy granting were associated with more child anxiety/depression. Unexpectedly, however, more maternal emotional warmth was related to higher levels of child anxiety/depression. The findings offer new insights to guide future research on the (mediating) role of parenting behaviours in the relation between children's negative emotionality and their internalizing problems. Copyright © 2010 John Wiley & Sons, Ltd.     

Shifting spatial attention makes you flip: Exogenous visual attention triggers perceptual alternations during binocular rivalry

Although it has been argued that visual attention and the dynamics of binocular rivalry are closely linked, strong evidence for this proposition is still lacking. Here, we investigate how perceptual alternations during binocular rivalry are affected by spatial attention by employing a cuing paradigm. We show a tight link between the occurrence of perceptual alternations and the spatiotemporal properties of visual attention: Alternations occurred earlier and more frequently at locations where visual attention was summoned by an exogenous cue. We argue that cuing a location where rival images are presented leads to a transient increase in the effective contrast of these rival images. This transient increase in effective contrast increases the probability of an alternation at that location. Furthermore, we suggest that an occipito-fronto-parietal network known to be involved in selective attention and binocular rivalry mediates perceptual alternations by boosting the neural response at attended locations.     

The facing bias in biological motion perception: Effects of stimulus gender and observer sex

Under orthographic projection, biological motion point-light walkers offer no cues to the order of the dots in depth: Views from the front and from the back result in the very same stimulus. Yet observers show a bias toward seeing a walker facing the viewer (Vanrie, Dekeyser, & Verfaillie, 2004). Recently, we reported that this facing bias strongly depends on the gender of the walker (Brooks et al., 2008). The goal of the present study was, first, to examine the robustness of the effect by testing a much larger subject sample and, second, to investigate whether the effect depends on observer sex. Despite the fact that we found a significant effect of figure gender, we clearly failed to replicate the strong effect observed in the original study. We did, however, observe a significant interaction between figure gender and observer sex.     

Implicit and explicit self-esteem in the context of internet addiction

Previous research has repeatedly found that people suffering from some clinical disorders (e.g., bulimia nervosa, depression) possess low explicit (i.e., conscious, deliberate) self-esteem while at the same time displaying high implicit (i.e., unconscious, automatic) self-esteem. This phenomenon has been termed damaged self-esteem and was proposed to be an indicator of psychological distress. Although Internet addiction has been found to be associated with low levels of explicit self-esteem, as well as with high levels of psychological distress, its relation to implicit self-esteem has, to our knowledge, not been investigated thus far. We therefore hypothesized that the phenomenon of damaged self-esteem could also be found amongst people suffering from Internet addiction, and conducted two studies using the Initial Preference Task as a measure of implicit self-esteem. As expected, we found that individuals scoring high on Internet addiction possess low explicit and high implicit self-esteem. This effect was, however, only found for the first name initial of the Initial Preference Task, leading to the conclusion that first and last name initials might tap into different parts of implicit self-esteem.     

Matching the message source to attitude functions: Implications for biased processing

A study was conducted to examine the hypothesis that matching (vs. mismatching) the source of a persuasive message to the functional basis of recipients’ attitudes may lead to positively biased processing. Under conditions conducive to effortful processing, high and low self-monitors were presented with a persuasive message ascribed to a source that either matched or mismatched the functional basis of their attitudes (i.e., an expert source for low self-monitors and an attractive source for high self-monitors). The message content was either unambiguous strong, unambiguous weak, or ambiguous. As predicted, given an ambiguous message biased processing led to more agreement when the source matched (vs. mismatched) attitude functions. In contrast, an unambiguous strong message led to more agreement than an unambiguous weak message regardless of source matching (unbiased processing). Results are discussed with respect to the role of the activation and use of heuristics in biased processing.     

Western esotericism: Towards an integrative model of interpretation

Despite the fact that during the last fifteen years we have witnessed the emergence of a research field of ‘Western esotericism’, scholars are still far from agreeing on definitions of ‘esotericism’. For an academic ‘field’, however, that wants to establish international networks and to bring together scholars from various research areas and disciplines, it is highly desirable to provide an interpretational framework in which these different studies find their place. The main argument of this article is that such common ground can be found only when esotericism is seen not as a selection of historical ‘currents’, however defined, but as a structural element of Western culture. After reviewing the most influential approaches to Western esotericism, this article identifies two dimensions of an esoteric discourse: claims of higher knowledge and ways of accessing this ‘truth’. To these dimensions can be added certain world views that are typically involved in there discourses. The interpretative model proposed here aims at critically addressing basic aspects of Western self-understanding including the rhetorics of rationality, science, enlightenment, progress and absolute truth. It postulates that conflicts of religious world views, identities and forms of knowledge lie at the heart of Western cultural history.