Factors affecting withdrawal from an escalating conflict: Quitting before it's too late

In an experimental study of “entrapping” conflicts —situations in which a decisionmaker may continue to expend resources in part to justify previous expenditures—subjects were given an initial stake of $4.00 and had the opportunity to win an additional $2.00 jackpot. Two independent variables (Process of Resource Allocation and Prior Limit-Setting) were combined in a 2 × 3 design. Once the subjects had started to invest, half of them had to make an “active” decision to continue. Unless they actively decided to continue, their investments automatically ceased and they were no longer eligible for the jackpot (Selfterminating condition). The other half only had to make a “passive” decision to continue. Unless they actively decided to dis continue, their investments for the jackpot automatically increased (Self-sustaining condition). In addition, before investments began, some subjects were asked to inform the experimenter of the nonbinding limit they had set on the amount they planned to invest (Public condition), some were asked to set a limit which they kept to themselves (Private condition), while a third group was not asked to set a limit (Control condition). Subjects invested significantly more money in the Self-sustaining condition. Also, investments were somewhat greater in the Control than the Public condition. Although the mean investments in the Public and Private conditions did not differ, those in the Public condition deviated significantly less from their earlier set limits, suggesting greater commitment to these limits. Theoretical and practical implications are discussed.     

Suicide ideation: its relation to depression, suicide and suicide attempt

A random sample of 3,935 adults from a general population were interviewed and asked to report how often they had thoughts of suicide as well as their opinion on the frequency of suicide ideation in others. Depression was found to be related to the respondent's reports of his/her own suicidal thoughts and to reports of frequent suicide ideation in others. A total of 5.4 percent of the respondents reported some degree of suicide ideation in the previous month and 9.1 percent reported that others think about suicide once a month or more. When the demographic characteristics of those who report suicide ideation in themselves or others were compared to those of suicide attempters and committers, some consistencies were found, suggesting that such questions may be useful in identifying those "at risk." Nevertheless, sufficient discrepancies were found which suggest that there may be a number of factors which increase or decrease the likelihood that someone with thoughts of suicide will attempt or commit suicide. Follow-up studies are necessary to uncover such factors and the degrees to which they influence the occurrence of suicide.     

Family and psychosocial predictors of obsessive compulsive disorder in a community sample of young adolescents

A two-stage epidemiologic study conducted between 1986 and 1988 in the southeastern United States investigated family and psychosocial predictors of obsessive compulsive disorder (OCD) and subclinical OCD in young adolescents. In the first stage, a life-event schedule and a family adaptability and cohesion scale were administered to a community sample of 3,283 adolescents. In stage two, the Schedule for Affective Disorders and Schizophrenia in School Age Children and the Children's Global Assessment Scale were administered to 488 mother-child pairs. In multivariable models family cohesion was the only significant correlate of OCD (odds ratio=0.95, 95% confidence interval 0.91–0.98). Gender, race, age, socioeconomic status, guardian status, adaptability, undesirable life events and desirable life events were not found to be significant predictors of OCD in models adjusting for cohesion. Note of the above variables were significantly associated with subclinical OCD. However, separate analyses of the 41 individual life events indicated seven specific events were significantly associated with OCD or subclinical OCD. These findings are at odds with the theory that overinvolvement of family members is a risk factor for OCD, though an association with overly rigid family structure cannot be eliminated based on these data. Further exploration of family characteristics is warranted.     

The effect of timing and spatial separation on the velocity of auditory apparent motion

Previously, it was shown that the minimum conditions for the illusion of auditory apparent motion (AAM) depend on stimulus timing but not spatial separation. In the present experiment, the effects of stimulus timing and source separation on the perceived velocity of AAM were examined. Eight listeners estimated the velocity, duration, and distance traveled of AAM, using a no-modulus, magnitude estimation procedure. Four burst durations (25, 50, 100, and 300 msec), 10 stimulus onset asynchronies (SOAs; 30, 40, 50, 60, 70, 80, 90, 100, 110, and 120 msec) and two separations (10° and 40°) were tested. Perceived velocity estimates were related to the total duration (burst duration + SOA) of the stimulus sequence. The effect of separation on velocity was extremely small but statistically significant. These results are similar to those obtained previously on the minimum conditions for AAM. Duration estimates were related only to total duration, but separation estimates were related to both separation and total duration. These results suggest that velocity is possibly a primary dimension of AAM that is independent of source separation.     

Rumination in Response to Stress as a Common Vulnerability Factor to Depression and Substance Misuse in Adolescence

The current study examined rumination in response to stress as a common vulnerability factor to both depression and substance use problems in adolescence. Specifically, we used a multi-wave longitudinal design to examine whether adolescents who tend to ruminate in response to stress exhibit increases in depressive symptoms and substance misuse following the occurrence of negative events. At time 1, adolescents (n = 161) completed measures assessing depressive symptoms, substance misuse, and the tendency to ruminate in response to stress. Every 6 weeks for the next 18 weeks participants completed measures assessing the occurrence of negative events, depressive symptoms, and substance misuse. Hierarchical linear modeling analyses indicated that adolescents who tend to ruminate in response to stress report greater elevations in depressive symptoms and substance misuse following elevations in negative events than other adolescents. The relationship between rumination, negative events, and substance misuse was moderated by age. Support was not obtained for fluctuations in depressive symptoms as a mediator of the relationship between negative events and substance misuse. Fluctuations in negative affect, however, were found to mediate this relationship.

Implicit sequence learning and conscious awareness

This paper uses the Process Dissociation Procedure to explore whether people can acquire unconscious knowledge in the serial reaction time task [Destrebecqz, A., & Cleeremans, A. (2001). Can sequence learning be implicit? New evidence with the Process Dissociation Procedure. Psychonomic Bulletin &Review, 8, 343-350; Wilkinson, L., & Shanks, D. R. (2004). Intentional control and implicit sequence learning. Journal of Experimental Psychology: Learning, Memory, and Cognition, 30, 354-369]. Experiment 1 showed that people generated legal sequences above baseline levels under exclusion instructions. Reward moved exclusion performance towards baseline, indicating that the extent of motivation in the test phase influenced the expression of unconscious knowledge. Experiments 2 and 3 revealed that even with reward, adding noise to the sequences or shortening training led to above-baseline exclusion performance, suggesting that task difficulty and the amount of training also affected the expression of unconscious knowledge. The results help resolve some current debates about the role of conscious awareness in sequence learning.     

Role of selective attention in artificial grammar learning

To investigate the role of selective attention in artificial grammar (AG) learning, participants were presented with “GLOCAL” strings—that is, chains of compound global and local letters. The global and local levels instantiated different grammars. The results of this experiment revealed that participants learned only the grammar for the level to which they attended. The participants were not even able to choose presented but unattended strings themselves. These results show that selective attention plays a critical role in AG learning.     

How does prior knowledge affect implicit and explicit concept learning?

Two experiments investigated the effect of prior knowledge on implicit and explicit learning. Implicit as opposed to explicit learning is sometimes characterized as unselective or purely statistical. During training, one group of participants was presented with category exemplars whose features could be tied together by integrative knowledge, whereas another group saw category exemplars with unrelated feature combinations. Half of the participants in each group learned these categories under a secondary-task condition (meant to discourage explicit learning), and the remaining half performed the categorization task under a single-task condition (meant to favour explicit learning). In a test phase, participants classified only the individual features of the training exemplars. Secondary- as opposed to single-task conditions impaired explicit but not implicit knowledge (as determined by subjective measures). Importantly, prior knowledge resulted in increased amounts of both implicit and explicit knowledge.