Unconscious symmetrical inferences: A role of consciousness in event integration

Explicit and implicit learning have been attributed to different learning processes that create different types of knowledge structures. Consistent with that claim, our study provides evidence that people integrate stimulus events differently when consciously aware versus unaware of the relationship between the events. In a first, acquisition phase participants sorted words into two categories (A and B), which were fully predicted by task-irrelevant primes-the labels of two other, semantically unrelated categories (C and D). In a second, test phase participants performed a lexical decision task, in which all word stimuli stemmed from the previous prime categories (C and D) and the (now nonpredictive) primes were the labels of the previous target categories (A and B). Reliable priming effects in the second phase demonstrated that bidirectional associations between the respective categories had been formed in the acquisition phase (A<-->C and B<-->D), but these effects were found only in participants that were unaware of the relationship between the categories! We suggest that unconscious, implicit learning of event relationships results in the rather unsophisticated integration (i.e., bidirectional association) of the underlying event representations, whereas explicit learning takes the meaning of the order of the events into account, and thus creates unidirectional associations.     

Phosphorylation state of CREB in the rat hippocampus: a molecular switch between spatial novelty and spatial familiarity?

The activation of cAMP response element-binding protein (CREB) after a learning experience is a common feature in the formation of several associative memories. We recently demonstrated that the increase in the hippocampal phosphorylated CREB (pCREB) levels 1 h after a short exploration of an open field (OF) was associated to detection of spatial novelty and was not related to the memory formation of habituation in this non-associative learning paradigm. Moreover, after a long training of three OF sessions, hippocampal pCREB levels were below to that observed in control rats. The present results show that such decrease does not correlate with memory retrieval or improvement in long-term memory of habituation. Instead, it is associated with the familiarity to the arena. Our experiments revealed that the relevant variable to induce CREB deactivation was the prolonged exploration of the arena (30 min). A 15 min OF exploration was ineffective. Furthermore, the last 5 min period of a prolonged exploration was crucial to change CREB phosphorylation state: when exploration took place in a novel arena the level of pCREB increased; in contrast, when it was performed in the familiar OF, pCREB levels decreased. Taken as a whole, our results suggest that CREB phosphorylation state in the hippocampus switches in response to exposure to a novel or to a familiar spatial environment.     

The worried mind: autonomic and prefrontal activation during worrying

To study the psychophysiological correlates of worrying, the authors recorded heart rate, respiratory sinus arrhythmia (RSA), skin conductance level, and alpha electroencephalographic asymmetry in healthy males during baseline, relaxation, worry induction, and anticipation of an impromptu speech task. Compared with baseline, relaxation, and anticipation, worrying was associated with greater heart rate and lower RSA. Worrying was further characterized by higher skin conductance levels compared with baseline but lower levels than during anticipation. Finally, worrying was associated with relatively greater left frontal activity compared with anticipation. Trait public speaking anxiety was positively correlated with left frontal activity during worrying. These results support the notion that worrying is a unique emotional state that is different from fearful anticipation.     

Aggressive adolescents benefit from massage therapy

Seventeen aggressive adolescents were randomly assigned to a massage therapy group or a relaxation therapy group to receive 20-minute therapy sessions, twice a week for five weeks. The massaged adolescents had lower anxiety after the first and last sessions. By the end of the study, they also reported feeling less hostile and they were perceived by their parents as being less aggressive. Significant differences were not found for the adolescents who were assigned to the relaxation group.     

Why people engage in parasuicide: a cross-cultural study of intentions

Information obtained at interview from 1,646 parasuicide patients in 14 regions in 13 European countries participating in the WHO/EURO Multicentre Study on Suicidal Behaviour was used to study self-reported intentions involved in parasuicide. Comparisons were made across cultures, genders, and age groups. Although some statistically significant differences were found, the effect sizes were very small. The main finding from this study is thus that parasuicide patients in different countries tend to indicate that similar types of intentions are involved in their acts of parasuicide, and that the intentions do not vary greatly with gender or age. The hypothesis that rates of suicide and parasuicide vary between regions with the frequency with which suicidal intention is indicated by the patients was also tested, but was supported only for women and in relation to national suicide rates. The findings from this study are likely to be generalizable to other settings and have implications for clinical practice.     

Adolescent suicidal ideation

Adolescent suicidal ideation and its relationship to other variables was tapped by a self-report questionnaire administered to 88 high school seniors. Eighteen percent responded positively to the statement "sometimes I feel suicidal." Those who reported suicidal ideation were found to differ from those who did not on a number of variables, including family relationships (quality of relationship with mother, intimacy with parents, and closeness to siblings), family history of depression (maternal depression), peer relations (quality of peer relationships, popularity, and number of friends), emotional well-being (happiness, anger, and depression), drug use (cigarettes, marijuana, and cocaine), and grade point average. Stepwise regression indicated that happiness explained 46% of the variance in suicidal ideation, and number of friends, anger, and marijuana use explained an additional 20%, for a total of 66% of the variance. While 34% of the variance remained unexplained, it is suggested that the questions used to measure these four variables be included in global screenings to identify adolescents at risk for suicidal ideation.     

Effects of task-relevant incentives on the electrophysiological correlates of error processing in major depressive disorder

Major depressive disorder (MDD) is associated with action-monitoring dysfunction—particularly, disrupted error processing. Whether such dysregulation is further modulated by task incentives is largely unknown. The goal of this study was to investigate possible dysfunctions in error processing in MDD as a function of varying task incentives and clinical profile. To this end, we recorded the error-related negativity (ERN) and error positivity (Pe) in 18 MDD participants and 18 healthy controls during a Stroop task that intermixed no-incentive and reward trials. Relative to controls, MDD participants showed (1) larger ERN irrespective of task incentives, and (2) reduced Pe during reward (but not no-incentive) trials. Moreover, among MDD participants, Pe amplitudes were negatively correlated with depression severity and clinical symptoms. The present findings highlight distinct effects of task incentives on electrophysiological components of error processing and are interpreted within current theories of action monitoring and incentive processing in depression.     

A 32-society investigation of the influence of perceived economic inequality on social class stereotyping

There is a growing body of work suggesting that social class stereotypes are amplified when people perceive higher levels of economic inequality—that is, the wealthy are perceived as more competent and assertive and the poor as more incompetent and unassertive. The present study tested this prediction in 32 societies and also examines the role of wealth-based categorization in explaining this relationship. We found that people who perceived higher economic inequality were indeed more likely to consider wealth as a meaningful basis for categorization. Unexpectedly, however, higher levels of perceived inequality were associated with perceiving the wealthy as less competent and assertive and the poor as more competent and assertive. Unpacking this further, exploratory analyses showed that the observed tendency to stereotype the wealthy negatively only emerged in societies with lower social mobility and democracy and higher corruption. This points to the importance of understanding how socio-structural features that co-occur with economic inequality may shape perceptions of the wealthy and the poor.     

Cognitive control: dynamic, sustained, and voluntary influences

The cost of incongruent stimuli is reduced when conflict is expected. This series of experiments tested whether this improved performance is due to repetition priming or to enhanced cognitive control. Using a paradigm in which Word and Number Stroop alternated every trial, Experiment 1 assessed dynamic trial-to-trial changes. Incongruent trials led to task-specific reduction of conflict (trial n + 2) without cross-task modulation (trial n + 1), but this was fully explained by repetition priming. In contrast, an increased ratio of incongruent words did lead to sustained task-specific enhancement, above and beyond repetition priming (Experiment 2). Experiments 3 and 4 assessed the voluntary modulation of cognitive control: A cue predicted the congruency of the incoming trial, allowing participants to establish the correct mindset (Word Stroop in Experiment 3, Flanker task in Experiment 4). Preparing oneself to process an incongruent word (or flanker) enhanced conflict resolution in the subsequent Number Stroop, an example of cross-task modulation. Taken together, these experiments reveal the multifaceted aspects of conflict resolution: Trial-to-trial changes are often due to repetition priming; sustained modulations brought about by task demands are task specific; and voluntary modulations are task general.