Classification of Attempted Suicide: A Review of Empirical Studies, 1963–1993

A review was carried out on empirical studies on the classification of attempted suicide over the period 1963-1993. Our aim was to investigate whether there is research evidence for a valid classification of homogeneous subgroups of suicide attempters. After assessment of the research quality, 32 studies were selected for comparison. Although there is lack of consistency among the studies, indications were found for two clearly distinguished subgroups characterized by mild and severe suicide attempts, which constitute the opposite poles of a one-dimensional concept of severity.     

Frustration and instrumentality of aggression

The influence of two different reinforcers of aggression was investigated: Frustration (intrinsic primary reinforcement) and instrumental value of aggression (extrinsic primary reinforcement). In the first part of the experiment frustration was manipulated on two levels by having the stooge interfere very often or seldom in the ?building a village' task of the subject. In the second part of the study the stooge had to judge distances in traffic while the subject was allowed to give him electrical shocks in order to startle and hinder the stooge in his estimation task. The aggression score of the subject was formed by the number and the intensity of the shocks delivered. Instrumentality of aggression was manipulated on two levels by indicating or not that the subjects could earn more money the more and stronger they shocked their partner. Confirming the predictions, significantly more aggression was expressed when this could lead to earning more money than in those conditions where this was not the case. Also confirming predictions, the impact of instrumentality on aggression was stronger than the influence of frustration. Frustration did not lead to a significant increase in the level of aggression.     

Habit,information acquisition,and the process of making travel mode choices

Three studies examined the role of habit on information acquisition concerning travel mode choices. On the basis of Triandis' (1980) model of attitude–behaviour relations it was expected that habit strength attenuates the elaborateness of choice processes. The studies focused on different phases in the choice process, namely the appreciation of situational cues and appreciation of choice option information. In line with expectations, it was found that, compared to weak habit participants, those who had a strong habit towards choosing a particular travel mode acquired less information and gave evidence of less elaborate choice strategies. It was attempted to break effects of habit by manipulating either accountability demands or level of attention. Although accountability demands raised the level of information acquisition, no interactions with habit were found. Enhanced attention to the choice process initially did override habit effects in a series of choice trials. However, in spite of this manipulation, chronic habit effects emerged during later trials. The results demonstrate the profound effects that habit may have on the appreciation of information about choice situations and choice options. ©1997 John Wiley & Sons, Ltd.     

Familial risk of early suicide: variations by age and sex of children and parents

To determine familial risk of early suicide, data on cause of death of all Dutch residents aged 20-55 years who died between 1995 and 2001 were linked to data of their parents. Men whose father died by suicide had a higher odds of suicide themselves, relative to men whose father died of other causes (Odds Ratio (OR): 2.5; 95% confidence interval: 1.8-3.6). This effect was slightly stronger in the case of mother's suicide (OR: 3.4; 2.3-5.0). The same effect was observed for women, for suicide by father (OR: 2.2; 1.3-3.7) and mother (OR: 4.6; 2.6-8.0). The odds of suicide increased with decreasing age at death of parent. Parental suicide is predictive for offspring suicide. Our data suggest that the predictive value is higher in case the mother died by suicide, particularly if the mother died by suicide at a young age.     

Habitual negative body image thinking as psychological risk factor in adolescents

Negative body image thinking can be broken down into cognitive content (body dissatisfaction thoughts) and the way such thoughts occur. The present study focused on negative body image thinking as mental habit, i.e., the degree to which such thinking occurs frequently and automatically [Verplanken, Friborg, Wang, Trafimow, & Woolf, 2007]. In a sample of 250 adolescents (age 12-15) it was found that negative body image thinking habit uniquely accounted for variance in self-esteem and eating disturbance propensity over and above body image dissatisfaction. Considering negative body image thinking as a mental habit contributes to a deeper understanding of body dissatisfaction in adolescents, and may have implications for interventions to deal with such attitudes and their potentially harmful consequences.     

Newborns' face recognition is based on spatial frequencies below 0.5 cycles per degree

A critical question in Cognitive Science concerns how knowledge of specific domains emerges during development. Here we examined how limitations of the visual system during the first days of life may shape subsequent development of face processing abilities. By manipulating the bands of spatial frequencies of face images, we investigated what is the nature of the visual information that newborn infants rely on to perform face recognition. Newborns were able to extract from a face the visual information lying from 0 to 1 cpd (Experiment 1), but only a narrower 0-0.5 cpd spatial frequency range was successful to accomplish face recognition (Experiment 2). These results provide the first empirical support of a low spatial frequency advantage in individual face recognition at birth and suggest that early in life low-level, non-specific perceptual constraints affect the development of the face processing system.     

Anxiety and post-traumatic stress symptoms following wisdom tooth removal

The purpose of the present study was to determine the psychological impact of wisdom teeth removal and to identify the psychological risk factors for the development of dental anxiety and post-traumatic stress symptoms. Participants were 34 consecutive elective patients referred for surgical removal of a wisdom tooth under local anesthesia. Frequency of previous distressing dental events and general traumatic life events were assessed at baseline (t1), and emotional distress (pain, state anxiety and disturbance) immediately after treatment (t2). Post-traumatic stress responses were determined three days after treatment (t3), and at four weeks follow-up (t4), while severity of dental trait anxiety was assessed at t1 and at t4. Two patients (8%) met screening criteria for Post-Traumatic Stress Disorder (PTSD) at t4. Multivariate analysis revealed that previous exposure to distressing dental events and pre-operative anxiety level predicted anxiety level at t4, accounting for 71% of the variance. Severity of pain during treatment was a significant predictor variable of PTSD symptom severity at t4 (25% explained variance). The findings underline the importance of pain-free treatments and awareness of patients' individual predisposition to anxiety or trauma-related symptoms to reduce the risk of iatrogenic psychological harm.