Decision Preceding Negativity in the Iowa Gambling Task: an ERP study

The present study aimed to investigate the slow negative potential (termed Decision Preceding Negativity, DPN, from the family of the Readiness Potential) which precedes a willed risky decision. To this end, evoked potentials preceding and following an economic choice were measured in a sample of 16 male students during the Iowa Gambling Task modified for ERPs recording. Statistics revealed reduced positivity/relative greater negativity (marking relative activation) in right prefrontal sites and reduced negativity (indicating relative inhibition of DPN) in central clusters over left premotor cortex, 500 ms before picking from economically disadvantageous risky decks. Analyses of the potentials elicited by the economic outcome (wins vs. losses) showed the classical frontal negativity (N260) to the economic losses. Results are consistent with the view that an economically risky decision is preceded by a relative inhibition of the planned motor response together with the activation of emotion-related right frontal sites.     

Motor timing and the preparation for sequential actions

Motor timing is essential for performing self-initiated movement sequences. Here, we investigated how sequence rhythm, or the timing for co-ordinating movements within a sequence, contributes to action preparation, compared with other processes occurring during sequence planning. First, we recorded the readiness potential (RP) in a condition of complex sequence rhythm and in condition of high demand on the timing for sequence initiation. We found that sequence rhythm and sequence initiation are independent processes, with sequence initiation contributing to early RP. Second, we compared the RP recorded in a condition of complex sequence rhythm and in a condition of complex sequence order, in which a complex combination of finger sub-movements had to be correctly ordered within a sequence. We found that sequence rhythm and sequence order share common processes occurring late RP. We suggest that the preparation for movement involves independent processes devoted to different aspects of motor timing and sequencing.     

Associations between sociocultural pressures to be thin, body distress, and eating disorder symptomatology among Chilean adolescent girls

This study explored the relationships between perceived sociocultural pressure to fulfill the thin beauty ideal, body distress, and the presence of eating disorder symptoms. Participants were 437 Chilean adolescent girls from Arica, northern Chile, aged 13-18. Results showed significant associations between perceived pressure from social agents to be thin and the presence of disrupted eating attitudes and behavior. The perceived influence of advertising, verbal messages and social situations related to eating and dieting emerged as the strongest predictors of eating disorders symptoms. Influence of advertising was also the strongest predictor of body image distress. Age differences emerged in perceived sociocultural pressure to be thin, with older participants reporting higher sociocultural pressure to fulfill the slender beauty ideal. This paper provides information about body distress and associated disturbances, a phenomenon which has seldom been studied in non-Western countries, but which has important health implications.     

Thinking ahead or not? Natural aging and anticipation during reading

Despite growing evidence of young adults neurally pre-activating word features during sentence comprehension, less clear is the degree to which this generalizes to older adults. Using ERPs, we tested for linguistic prediction in younger and older readers by means of indefinite articles (a’s and an’s) preceding more and less probable noun continuations. Although both groups exhibited cloze probability-graded noun N400s, only the young showed significant article effects, indicating probabilistic sensitivity to the phonology of anticipated upcoming nouns. Additionally, both age groups exhibited prolonged increased frontal positivities to less probable nouns, although in older adults this effect was prominent only in a subset with high verbal fluency (VF). This ERP positivity to contextual constraint violations offers additional support for prediction in the young. For high VF older adults, the positivity may indicate they, too, engage in some form of linguistic pre-processing when implicitly cued, as may have occurred via the articles.     

Life review therapy using autobiographical retrieval practice for older adults with clinical depression

The aim of this experiment was to examine the efficacy of life review based on autobiographical retrieval practice for treating depression in older adults. Thirty-seven clinically depressed older adults aged 64-83, who were also receiving pharmacological treatment, were randomly assigned to life review therapy or to a placebo condition with supportive therapy. Results indicated decreased depression for both conditions, with no significant differences between the two therapies. There was some indication of greater gain in production of specific memories among those in life review therapy. Patients who produced higher numbers of specific memories decreased their depression scores at a faster rate.     

The relationship between need for closure and memory for schema-related information among younger and older adults

Two studies were conducted to examine the relationships among need for closure (NFC) and schematic information processing in younger and older adults. The results show increased NFC to be associated with less schematic processing (i.e., less memory for schema-consistent items, and more memory for schema-irrelevant items, out of all items memorized correctly), among older than younger adults. The findings of the studies are interpreted as demonstrating the age-associated deficit in information processing consistent with the level of NFC. Moreover, the results indicate that positive mood may play a role in facilitating information processing consistent with the level of NFC among older and younger adults. Finally, we present a framework for predicting when older adults will and will not effectively use schematic processing, considered a compensatory strategy for decline in cognitive abilities.     

Asymmetry in the estimation of interpersonal distance and identity affirmation

An asymmetry effect is known to exist in the estimation of interpersonal distance, depending on whether the point of reference for the estimation is the subject (‘How far are the others from you?’) or the others How far are you from the others?). It looks as though, through the effect of a self-centring schema, subjects feel that others occupy their own space more than they occupy the space of others. A self-centring schema has also been found in many other processes involving judgment or comparison of oneself and others. It is generally interpreted as a sign of the affirmation and defence of personal identity. The three experiments reported here attempt to relate the asymmetries in the distances perceived between persons represented on a map to the following three areas in which one's sense of personal or group identity is involved: (1) in the perception of one's own specificity with respect to others (or of the specificity of the group to which one belongs with respect to other groups) (experiment 1), (2) in one's ability to put oneself in the place of others (exocentrism) (experiment 2). and (3) in the individuation of oneself by others (experiment 3). The results of these three experiments lead us to believe that it is indeed the processes of identification and affirmation of personal and group identity - along with the underlying categorization processes — that are the source of the asymmetries observed in interpersonal distance estimation. The consistency of the data obtained in different situations also validates the technique used for estimating interpersonal distance.     

PERSONALITY,DEMOGRAPHICS, AND ACCULTURATION OF VIETNAMESE AND NICARAGUAN REFUGEES TO THE UNITED STATES

The influx of refugees into the United States in recent years has led to a new interest in acculturation on the part of North American psychologists. Previous research in this area has usually focused on demographic, rather than psychological, variables as predictors of a willingness to acculturate. Using samples of Nicaraguan and Vietnamese refugees, the present study compared personality factors and age, level of education, and time in the U.S. as predictors of acculturation. Although results for the Nicaraguans were mixed, personality factors emerged as being better predictors in the Vietnamese group. This suggests that, in some cases, personality factors may be more basic to the process of acculturation than previously assumed.     

Event-related potential studies of cerebral specialization during reading : II. Studies of congenitally deaf adults

A number of methodological features were incorporated in a paradigm designed to maximize the likelihood of finding reliable event-related potential (ERP) signs of functional specializations between and within the cerebral hemispheres. Every subject was more accurate in identifying words presented to the right than to the left visual field. The morphology of the ERPs elicited by these words varied considerably as a function of electrode position both within and between the hemispheres. Amplitude asymmetries of ERP components recorded from occipital regions of the two hemispheres varied systematically with the position of the word in the visual field. On the other hand, ERPs from more anterior (temporal and frontal) regions displayed large asymmetries which were in the same direction regardless of the visual field of word presentation. The most prominent such asymmetry was in the negativity in the region 300–500 msec (N410) which was larger in the left than the right hemisphere in every subject. These results demonstrate that in this paradigm which demands specialized language processing ERPs are sensitive to aspects of cerebral organization both within and between the two hemispheres.