Coding strategies in number space: memory requirements influence spatial-numerical associations

The tendency to respond faster with the left hand to relatively small numbers and faster with the right hand to relatively large numbers (spatial numerical association of response codes, SNARC effect) has been interpreted as an automatic association of spatial and numerical information. We investigated in two experiments the impact of task-irrelevant memory representations on this effect. Participants memorized three Arabic digits describing a left-to-right ascending number sequence (e.g., 3-4-5), a descending sequence (e.g., 5-4-3), or a disordered sequence (e.g., 5-3-4) and indicated afterwards the parity status of a centrally presented digit (i.e., 1, 2, 8, or 9) with a left/right keypress response. As indicated by the reaction times, the SNARC effect in the parity task was mediated by the coding requirements of the memory tasks. That is, a SNARC effect was only present after memorizing ascending or disordered number sequences but disappeared after processing descending sequences. Interestingly, the effects of the second task were only present if all sequences within one experimental block had the same type of order. Taken together, our findings are inconsistent with the idea that spatial-numerical associations are the result of an automatic and obligatory cognitive process but do suggest that coding strategies might be responsible for the cognitive link between numbers and space.     

The influence of stress hormones on emotional memory: relevance for psychopathology

Substantial progress within recent years has led to a better understanding of the impact of stress on emotional memory. These effects are of relevance for understanding and treating psychopathology. The present selective review describes how emotional memory is modulated through stress hormones. Acute as well as chronic effects are discussed and information from rodent models is compared to human experimental studies and clinical observations. Finally, the relevance of these findings for emotional memory disturbances in psychiatric disorders is exemplified by discussions on neuroendocrine alterations in depression, post traumatic stress disorder and phobias.     

Trading performance,disposition effect,overconfidence, representativeness bias,and experience of emerging market investors

Using brokerage account data from China, we study investment decision making in an emerging market. We find that Chinese investors make poor trading decisions: the stocks they purchase underperform those they sell. We also find that Chinese investors suffer from three behavioral biases: (i) they tend to sell stocks that have appreciated in price, but not those that have depreciated in price, consistent with a disposition effect, acknowledging gains but not losses; (ii) they seem overconfident; and (iii) they appear to believe that past returns are indicative of future returns (a representativeness bias). In comparisons to prior findings, Chinese investors seem more overconfident than U.S. investors (i.e., the Chinese hold fewer stocks, yet trade very often) and their disposition effect appears stronger. Finally, we categorize Chinese investors based on proxy measures of experience and find that “experienced” investors are not always less prone to behavioral biases than are “inexperienced” ones. Copyright © 2007 John Wiley & Sons, Ltd.     

Is Theory of Mind Understanding Impaired in Males with Fragile X Syndrome?

Males with fragile X syndrome (FXS) have difficulties with social interaction and many show autistic features. This study examined whether the social deficits characteristic of FXS are associated with theory of mind difficulties. Two groups of boys with FXS participated: a group with few autistic features and a group with many autistic features. An intellectual disability control group also participated. In addition to using standard theory of mind tasks, new techniques were used that were able to separate out the various processing demands of the task (e.g., memory, inhibitory control). Overall, the findings indicate that both groups of boys with FXS have difficulty with theory of mind tasks compared to an intellectual disability control group. However, both groups with FXS also performed worse on comparison trials that required working memory but not theory of mind. Theory of mind difficulties are likely to be an important aspect of the FXS clinical profile, but are most likely the result from a more basic difficulty with working memory.     

Internal clock processes and the filled-duration illusion

In 3 experiments, the authors compared duration judgments of filled stimuli (tones) with unfilled ones (intervals defined by clicks or gaps in tones). Temporal generalization procedures (Experiment 1) and verbal estimation procedures (Experiments 2 and 3) all showed that subjective durations of the tones were considerably longer than those of unfilled intervals defined either by clicks or gaps, with the unfilled intervals being judged as approximately 55%-65% of the duration of the filled ones when real duration was the same. Analyses derived from the pacemaker-switch-accumulator clock model incorporated into scalar timing theory suggested that the filled/unfilled difference in mean estimates was due to higher pacemaker speed in the former case, although conclusively ruling out alternative interpretations in terms of attention remains difficult.     

Culture and teasing: the relational benefits of reduced desire for positive self-differentiation

The authors hypothesized that teasing, a social interaction that benefits relational bonds at the expense of the self, should be viewed as more affiliative, and experienced as more pleasurable, by members of cultures that deemphasize positive self-differentiation. In four multimethod studies, Asian Americans attributed more affiliative intent to teasers and reported more positive target experience than did European Americans. Teaser behavior, attribution biases, and personality did not account for culture-related differences in teasing experience. Rather, childhood teasing may better prepare Asian American children to overlook a tease's affront to the self in favor of its relational rewards. Implications of deemphasizing positive self-differentiation in social interaction are discussed.     

Emotions over time: synchronicity and development of subjective, physiological, and facial affective reactions to music

Most people are able to identify basic emotions expressed in music and experience affective reactions to music. But does music generally induce emotion? Does it elicit subjective feelings, physiological arousal, and motor reactions reliably in different individuals? In this interdisciplinary study, measurement of skin conductance, facial muscle activity, and self-monitoring were synchronized with musical stimuli. A group of 38 participants listened to classical, rock, and pop music and reported their feelings in a two-dimensional emotion space during listening. The first entrance of a solo voice or choir and the beginning of new sections were found to elicit interindividual changes in subjective feelings and physiological arousal. Quincy Jones' "Bossa Nova" motivated movement and laughing in more than half of the participants. Bodily reactions such as "goose bumps" and "shivers" could be stimulated by the "Tuba Mirum" from Mozart's Requiem in 7 of 38 participants. In addition, the authors repeated the experiment seven times with one participant to examine intraindividual stability of effects. This exploratory combination of approaches throws a new light on the astonishing complexity of affective music listening.