Showing papers on "Poison control published in 1994"

Behavioral inhibition, behavioral activation, and affective responses to impending reward and punishment: The BIS/BAS Scales

Abstract: J. A. Gray (1981, 1982) holds that 2 general motivational systems underlie behavior and affect: a behavioral inhibition system (BIS) and a behavioral activation system (BAS). Self-report scales to assess dispositional BIS and BAS sensitivities were created. Scale development (Study 1) and convergent and discriminant validity in the form of correlations with alternative measures are reported (Study 2). In Study 3, a situation in which Ss anticipated a punishment was created. Controlling for initial nervousness, Ss high in BIS sensitivity (assessed earlier) were more nervous than those low in BIS sensitivity. In Study 4, a situation in which Ss anticipated a reward was created. Controlling for initial happiness, Ss high in BAS sensitivity (Reward Responsiveness and Drive scales) were happier than those low in BAS sensitivity. In each case the new scales predicted better than an alternative measure. Discussion is focused on conceptual implications.

The earth is round (p < .05)

Abstract: After 4 decades of severe criticism, the ritual of null hypothesis significance testing (mechanical dichotomous decisions around a sacred .05 criterion) still persists. This article reviews the problems with this practice, including near universal misinterpretation of p as the probability that H₀ is false, the misinterpretation that its complement is the probability of successful replication, and the mistaken assumption that if one rejects H₀ one thereby affirms the theory that led to the test. Exploratory data analysis and the use of graphic methods, a steady improvement in and a movement toward standardization in measurement, an emphasis on estimating effect sizes using confidence intervals, and the informed use of available statistical methods are suggested. For generalization, psychologists must finally rely, as has been done in all the older sciences, on replication. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

Dual-task interference in simple tasks: Data and theory.

Abstract: People often have trouble performing 2 relatively simple tasks concurrently. The causes of this interference and its implications for the nature of attentional limitations have been controversial for 40 years, but recent experimental findings are beginning to provide some answers. Studies of the psychological refractory period effect indicate a stubborn bottleneck encompassing the process of choosing actions and probably memory retrieval generally, together with certain other cognitive operations. Other limitations associated with task preparation, sensory-perceptual processes, and timing can generate additional and distinct forms of interference. These conclusions challenge widely accepted ideas about attentional resources and probe reaction time methodologies. They also suggest new ways of thinking about continuous dual-task performance, effects of extraneous stimulation (e.g., stop signals), and automaticity. Implications for higher mental processes are discussed.

Adaptive representation of dynamics during learning of a motor task

Abstract: We investigated how the CNS learns to control movements in different dynamical conditions, and how this learned behavior is represented. In particular, we considered the task of making reaching movements in the presence of externally imposed forces from a mechanical environment. This environment was a force field produced by a robot manipulandum, and the subjects made reaching movements while holding the end-effector of this manipulandum. Since the force field significantly changed the dynamics of the task, subjects' initial movements in the force field were grossly distorted compared to their movements in free space. However, with practice, hand trajectories in the force field converged to a path very similar to that observed in free space. This indicated that for reaching movements, there was a kinematic plan independent of dynamical conditions. The recovery of performance within the changed mechanical environment is motor adaptation. In order to investigate the mechanism underlying this adaptation, we considered the response to the sudden removal of the field after a training phase. The resulting trajectories, named aftereffects, were approximately mirror images of those that were observed when the subjects were initially exposed to the field. This suggested that the motor controller was gradually composing a model of the force field, a model that the nervous system used to predict and compensate for the forces imposed by the environment. In order to explore the structure of the model, we investigated whether adaptation to a force field, as presented in a small region, led to aftereffects in other regions of the workspace. We found that indeed there were aftereffects in workspace regions where no exposure to the field had taken place; that is, there was transfer beyond the boundary of the training data. This observation rules out the hypothesis that the subject's model of the force field was constructed as a narrow association between visited states and experienced forces; that is, adaptation was not via composition of a look-up table. In contrast, subjects modeled the force field by a combination of computational elements whose output was broadly tuned across the motor state space. These elements formed a model that extrapolated to outside the training region in a coordinate system similar to that of the joints and muscles rather than end-point forces. This geometric property suggests that the elements of the adaptive process represent dynamics of a motor task in terms of the intrinsic coordinate system of the sensors and actuators.

Actual Causes of Death in the United States

Abstract: To the Editor. —The article entitled "Actual Causes of Death in the United States"1was misleading in a number of ways. First, the title should have been something like "Nongenetic Causes of Death" or "Potentially Preventable Nongenetic Causes of Premature Death," or adjustments should have been made so that ordinary causes of death not credited to one of Drs McGinnis and Foege's major external factors were kept in. Otherwise, listing nine or 10 leading "actual causes" misleadingly suggests that heart disease and cancers are not leading causes of death. In fact, subtract those cancers and heart diseases that McGinnis and Foege attribute to external causes, lifestyles, and the like, and heart disease remains comfortably in third place as a cause of death, and cancers not attributable to outside influences kill more than toxic agents do. Second, either some deaths are counted twice or virtually no firearm-related deaths are attributed

Toward a functional analysis of self-injury

Abstract: This study describes the use of an operant methodology to assess functional relationships between self-injury and specific environmental events. The self-injurious behaviors of nine developmentally disabled subjects were observed during periods of brief, repeated exposure to a series of analogue conditions. Each condition differed along one or more of the following dimensions: (1) play materials (present vs absent), (2) experimenter demands (high vs low), and (3) social attention (absent vs noncontingent vs contingent). Results showed a great deal of both between and within-subject variability. However, in six of the nine subjects, higher levels of self-injury were consistently associated with a specific stimulus condition, suggesting that within-subject variability was a function of distinct features of the social and/or physical environment. These data are discussed in light of previously suggested hypotheses for the motivation of self-injury, with particular emphasis on their implications for the selection of suitable treatments.

Assessment of fracture risk and its application to screening for postmenopausal osteoporosis: synopsis of a WHO report. WHO Study Group.

Abstract: The criteria required for an effective screening strategy for osteoporosis are largely met in Caucasian women. The disease is common and readily diagnosed by the measurement of bone mineral with single- or dual-energy absorptiometry. Such measurements have high specificity but lower sensitivity, so that the value of the technique is greater for those identified as being at higher risk. Against this background there is little evidence that osteoporosis can usefully be tackled by a public health policy to influence risk factors such as smoking, exercise and nutrition. This suggests that it is appropriate to consider targetting of treatment with agents affecting bone metabolism to susceptible individuals. Since the main benefits of the use of hormone replacement therapy (HRT) are probably on cardiovascular morbidity, the major role for selective screening is to direct non-HRT interventions. An appropriate time to consider screening and intervention is at the menopause, but screening at later ages is also worthy of consideration. Since the cost of screening is low and that of bone-active drugs is high, the selective use of screening techniques will improve the cost-benefit ratio of intervention.

Health and Behavioral Consequences of Binge Drinking in College: A National Survey of Students at 140 Campuses

Abstract: Objective. —To examine the extent of binge drinking by college students and the ensuing health and behavioral problems that binge drinkers create for themselves and others on their campus. Design. —Self-administered survey mailed to a national representative sample of US 4-year college students. Setting. —One hundred forty US 4-year colleges in 1993. Participants. —A total of 17592 college students. Main Outcome Measures. —Self-reports of drinking behavior, alcohol-related health problems, and other problems. Results. —Almost half (44%) of college students responding to the survey were binge drinkers, including almost one fifth (19%) of the students who were frequent binge drinkers. Frequent binge drinkers are more likely to experience serious health and other consequences of their drinking behavior than other students. Almost half (47%) of the frequent binge drinkers experienced five or more different drinking-related problems, including injuries and engaging in unplanned sex, since the beginning of the school year. Most binge drinkers do not consider themselves to be problem drinkers and have not sought treatment for an alcohol problem. Binge drinkers create problems for classmates who are not binge drinkers. Students who are not binge drinkers at schools with higher binge rates were more likely than students at schools with lower binge rates to experience problems such as being pushed, hit, or assaulted or experiencing an unwanted sexual advance. Conclusions. —Binge drinking is widespread on college campuses. Programs aimed at reducing this problem should focus on frequent binge drinkers, refer them to treatment or educational programs, and emphasize the harm they cause for students who are not binge drinkers. (JAMA. 1994;272:1672-1677)

A new, semi-structured psychiatric interview for use in genetic linkage studies: a report on the reliability of the SSAGA.

Abstract: Within- and cross-center test-retest studies were conducted to study the reliability of a new, semistructured, comprehensive, polydiagnostic psychiatric interview being used in a multisite genetic linkage study of alcoholism. Findings from both studies indicated that reliability for the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) was high for DSM-III-R substance dependence disorders, but less so for substance abuse disorders. Reliability of depression was good in both studies, but mixed for antisocial personality disorder (ASP). Findings are presented in terms of specific substance dependence and abuse diagnoses, as well as for depression and ASP. Criterion-specific reliabilities are examined by type of substance used. Although SSAGA was designed to provide for broad phenotyping of alcoholism, review of its new features suggests its suitability for a variety of family studies, not just those focusing on substance abuse.

International Standards for Neurological and Functional Classification of Spinal Cord Injury. American Spinal Injury Association.

Abstract: The International Standards Booklet for Neurological and Functional Classification of Spinal Cord Injury

Economic Stress, Coercive Family Process, and Developmental Problems of Adolescents

Abstract: We propose a model of family conflict and coercion that links economic stress in family life to adolescent symptoms of internalizing and externalizing emotions and behaviors. The 180 boys and 198 girls in the study were living in intact families in the rural Midwest, an area characterized by economic decline and uncertainty. Theoretical constructs in the model were measured using both trained observer and family member reports. These adolescents and their parents were interviewed each year for 3 years during the seventh, eighth, and ninth grades. Our theoretical model proposes that economic pressure experienced by parents increases parental dysphoria and marital conflict as well as conflicts between parents and children over money. High levels of spousal irritability, coupled with coercive exchanges over money matters, were expected to be associated with greater hostility in general by parents toward their children. These hostile/coercive exchanges were expected to increase the likelihood of adolescent emotional and behavioral problems. Overall, results were consistent with the proposed model. Moreover, the hypothesized processes applied equally well to the behavior of mothers and fathers, as well as sons and daughters.

Bullying at School: Basic Facts and Effects of a School Based Intervention Program

Abstract: VioLit Summary: OBJECTIVE: The purpose of this paper by Olweus was to review the literature that examined bullying in school. METHODOLOGY: The author reviewed both literature dealing with the incidence of bullying in schools in Norway and Sweden and the results of an evaluation of a school intervention program aimed at bullying. FINDINGS/DISCUSSION: The author began by defining bullying and supplying general information. He defined bullying as being when a student is "exposed repeatedly and over time, to negative actions on the part of one or more other students" (p.1173). In one study, it was reported that in the majority of cases, the victim is harassed by a group of at least two or three students. The author next supplied some basic facts about bully/victim problems. In a Norwegian study of 130,000 students, 15% of students in elementary and secondary/junior high school were involved in bully/victim problems on a regular basis. The studies showed that the percentage of students who reported being bullied decreased with higher grade levels. The studies also showed that bullying was carried out by older students, while victims were younger. The trend appeared to be that boys were more exposed to bullying than girls. However, girls were more exposed to indirect and more subtle forms of bullying (social isolation, etc...) than to bullying with open attack. Boys carried out a large portion of the bullying to which girls were subjected. But, in general, boys were more often both victims and perpetrators of direct bullying. The author next looked at what the literature revealed about three common myths about bullying. The author stated that the first myth is that bullying is a consequence of large classes and schools. The literature refuted this. Next, the author reported that the second myth is that bullying is a consequence of competition and striving for grades. LISREL analysis of the data showed that this was not correct. Finally, the author examined the myth that explained victimization as caused by external deviation (physical appearance, etc...). But, once again, the author found no empirical support of this in the literature he reviewed. In the next section of the paper, the author examined typical victim characteristics. Studies showed that typical victims were more anxious, lonely, and insecure than other students. Victims also had fewer friends. This type of victim was called a passive or submissive victim, characterized by an anxious or submissive reaction pattern combined with physical weakness. A smaller group, provocative victims, were characterized by a variety of both anxious and aggressive reaction patterns. The studies also revealed that bullies were characterized by aggression toward both their peers and, in some cases, adults. They had more positive attitudes toward violence. They expressed impulsivity and a strong need to dominate others. Although passive bullies exist (people who participate in bullying but do not take the initiative), typical bullies were described as being very aggressive and physically strong. The author next identified four factors that have been found to be important in terms of the upbringing and other conditions that were present that may have been conducive to the development of an aggressive reaction: basic emotional attitude of the caretaker(s) toward the child during the early years, permissiveness towards aggressive behavior by the child, use of power-assertive child rearing practices, and the general temperament of the child. Finally, the author identified some group mechanisms that appear to be at work when bullying is done in groups: social contagion, weakening of the controls and inhibitors against aggressive tendencies, diffusion of responsibility, and gradual cognitive changes in the perceptions of bullying and the victim. In the last section of the paper, the author described results of an evaluation of an intervention program he developed and implemented against bullying in school. The evaluation was on the effects of an intervention program based on data from 2,500 students belonging to 112 grade 4-7 classes in 42 primary and secondary/junior high schools in Norway. The data was collected four months after the introduction of the program and then one year and two years later. The author stated the following results(1) marked reductions in levels of bully/victim problems for the time periods studied, (2) similar reductions obtained for the aggregated peer rating variables, (3) no displacement of bullying to before or after school, (4) clear reduction in general antisocial behavior, (5) improved social climate of the school, and (6) increased student satisfaction with school life in general. The author concluded that the above results were likely to be mainly a consequence of the intervention program implemented. (CSPV Abstract - Copyright © 1992-2007 by the Center for the Study and Prevention of Violence, Institute of Behavioral Science, Regents of the University of Colorado) KW - Blueprints Model Reference KW - Bullying Prevention KW - Bullying Intervention KW - School Based KW - Intervention Program KW - Juvenile Offender KW - Child Offender KW - Bully Offender KW - School Violence KW - Norway KW - Sweden KW - Countries Other Than USA KW - Bully Victim KW - Victim Characteristics KW - Offender Characteristics KW - Child Victim KW - Juvenile Victim KW - Violence Intervention KW - Program Evaluation KW - Program Effectiveness KW - Victim Characteristics KW - Child Violence KW - Juvenile Violence KW - Literature Review KW - Prevention Program KW - Juvenile Bully KW - Child Bully KW - Early Adolescence KW - Late Childhood KW - Elementary School Student KW - Junior High School Student KW - Grade 4 KW - Grade 5 KW - Grade 6 KW - Grade 7 Language: en

Gender, race, and perception of environmental health risks

Abstract: This paper reports the results of a national survey in which perceptions of environmental health risks were measured for 1275 white and 214 nonwhite persons. The results showed that white women perceived risks to be much higher than did white men, a result that is consistent with previous studies. However, this gender difference was not true of nonwhite women and men, whose perceptions of risk were quite similar. Most striking was the finding that white males tended to differ from everyone else in their attitudes and perceptions--on average, they perceived risks as much smaller and much more acceptable than did other people. These results suggest that socio-political factors such as power, status, alienation, and trust are strong determiners of people's perception and acceptance of risks.

Typologies of male batterers: Three subtypes and the differences among them.

Abstract: Previous typologies of male batterers, including typologies developed by means of rational-deductive and empirical-inductive strategies, are reviewed. On the basis of this review, 3 descriptive dimensions (i.e., severity of marital violence, generality of the violence [toward the wife or toward others], and psychopathology/personality disorders) that consistently have been found to distinguish among subtypes of batterers are identified. These dimensions are used to propose a typology consisting of 3 subtypes of batterers (i.e., family only, dysphoric/borderline, and generally violent/antisocial). A developmental model of marital violence is then presented, and the previous literature is reviewed to examine how each batterer subtype might differ on variables of theoretical interest. Finally, some of the methodological limitations of previous typology research are reviewed, and suggestions for future work are offered.

A Prospective Study of Postural Balance and Risk of Falling in An Ambulatory and Independent Elderly Population

Abstract: BACKGROUND: An ability to predict risk of future falling is needed in order to target high-risk individuals for preventive intervention. The purpose of this study was to compare the ability of different measures of postural balance to predict risk of falling prospectively in an ambulatory and independent elderly population. METHODS: Balance tests were performed on 100 volunteers (aged 62-96), and falling was then monitored prospectively over a one-year period. The balance testing comprised measurements of: (a) spontaneous postural sway, (b) induced anterior-posterior sway, (c) induced medial-lateral sway, (d) anticipatory adjustments preceding volitional arm movements, (e) timed one-leg stance, and (f) performance on a clinical balance assessment scale. Small pseudorandom platform motions were used to perturb balance in the induced-sway tests. Using force plates, the spontaneous- and induced-sway responses were quantified in terms of the amplitude, speed, and mean frequency of the center-of-pressure displacement; input-output models were also used to parameterize the induced-sway performance. RESULTS: Although a number of measures showed evidence of significant differences between fallers and nonfallers, the differences were most pronounced for measures related to the control of lateral stability. Lateral spontaneous-sway amplitude (blindfolded conditions) was found to be the single best predictor of future falling risk, particularly for the large group of falls that were precipitated by a biomechanical perturbation. This measure was able to predict future falling risk with moderate accuracy, even in those individuals with no recent history of falling. CONCLUSIONS: The results suggest that control of lateral stability may be an important area for fall-preventative intervention. The ability of a simple and safe force-plate measure of spontaneous postural sway to predict future falling risk suggests a possible clinical application as a preliminary screening tool for risk of falling. Language: en

Mortality in relation to consumption of alcohol: 13 years' observations on male British doctors

Abstract: Objective : To assess the risk of death associated20with various patterns of alcohol consumption. Design - Prospective study of mortality in relation to alcohol drinking habits in 1978, with causes of death sought over the next 13 years (to 1991). Subjects : 12 321 British male doctors born between 1900 and 1930 (mean 1916) who replied to a postal questionnaire in 1978. Those written to in 1978 were the survivors of a long running prospective study of the effects of smoking that had begun in 195120and was still continuing. Results - Men were divided on the basis of their response to the 1978 questionnaire into two groups according to whether or not they had ever had any type of vascular disease, diabetes, or “life threatening disease” and into seven groups according to the amount of alcohol they drank. By 1991 almost a third had died. All statistical analyses of mortality were standardised for age, calendar year, and smoking habit. There was a U shaped relation between all cause mortality and the average amount of alcohol reportedly drunk; those who reported drinking 8-14 units of alcohol a week (corresponding to an average of one to two units a day) had the lowest risks. The causes of death were grouped into three main categories: “alcohol augmented” causes (6% of all deaths: cirrhosis, liver cancer, upper aerodigestive (mouth, oesophagus, larynx, and pharynx) cancer, alcoholism, poisoning, or injury), ischaemic heart disease (33% of all deaths), and other causes. The few deaths from alcohol augmented causes showed, at least among regular drinkers, a progressive trend, with the risk increasing with dose. In contrast, the many deaths from ischaemic heart disease showed no significant trend among regular drinkers, but there were significantly lower rates in regular drinkers than in non-drinkers. The aggregate of all other causes showed a U shaped dose-response relation similar to that for all cause mortality. Similar differences persisted irrespective of a history of previous disease, age (under 75 or 75 and older), and period of follow up (first five and last eight years). Some, but apparently not much, of the excess mortality in non-drinkers could be attributed to the inclusion among them of a small proportion of former drinkers. Conclusion : The consumption of alcohol appeared to reduce the risk of ischaemic heart disease, largely irrespective of amount. Among regular drinkers mortality from all causes combined increased progressively with amount drunk above 21 units a week. Among British men in middle or older age the consumption of an average of one or two units of alcohol a day is associated with significantly lower all cause mortality than is the consumption of no alcohol, or the consumption of substantial amounts. Above about three units (two American20units) of alcohol a day, progressively greater levels of consumption are associated with progressively higher all cause mortality.

Socialization Mediators of the Relation between Socioeconomic Status and Child Conduct Problems

Abstract: The goal was to examine processes in socialization that might account for an observed relation between early socioeconomic status and later child behavior problems. A representative sample of 585 children (n = 51 from the lowest socioeconomic class) was followed from preschool to grade 3. Socioeconomic status assessed in preschool significantly predicted teacher-rated externalizing problems and peer-rated aggressive behavior in kindergarten and grades 1, 2, and 3. Socioeconomic status was significantly negatively correlated with 8 factors in the child's socialization and social context, including harsh discipline, lack of maternal warmth, exposure to aggressive adult models, maternal aggressive values, family life stressors, mother's lack of social support, peer group instability, and lack of cognitive stimulation. These factors, in turn, significantly predicted teacher-rated externalizing problems and peer-nominated aggression and accounted for over half of the total effect of socioeconomic status on these outcomes. These findings suggest that part of the effect of socioeconomic status on children's aggressive development may be mediated by status-related socializing experiences.

A Psychological Study of the Inverse Relationship Between Perceived Risk and Perceived Benefit

Abstract: Judgments of risk and judgments of benefit have been found to be inversely related. Activities or technologies that are judged high in risk tend to be judged low in benefit, and vice versa. In the present study, we examine this inverse relationship in detail, using two measures of relationship between risk and benefit. We find that the inverse relationship is robust and indicative of a confounding of risk and benefit in people's minds. This confounding is linked to a person's overall evaluation of an activity or technology. Theoretical and practical implications of this risk-benefit confounding are discussed.

Where we look when we steer

Abstract: STEERING a car requires visual information from the changing pattern of the road ahead. There are many theories about what features a driver might use1–3, and recent attempts to engineer self-steering vehicles have sharpened interest in the mechanisms involved4,5 However, there is little direct information linking steering performance to the driver's direction of gaze3. We have made simultaneous recordings of steering-wheel angle and drivers' gaze direction during a series of drives along a tortuous road. We found that drivers rely particularly on the 'tangent point' on the inside of each curve, seeking this point 1–2 s before each bend and returning to it throughout the bend. The direction of this point relative to the car's heading predicts the curvature of the road ahead, and we examine the way this information is used.

The International Personality Disorder Examination: The World Health Organization/Alcohol, Drug Abuse, and Mental Health Administration International Pilot Study of Personality Disorders

Abstract: Background: One of the aims of the World Health Organization/Alcohol, Drug Abuse, and Mental Health Administration joint program on psychiatric diagnosis and classification is the development and standardization of diagnostic assessment instruments for use in clinical research worldwide. The International Personality Disorder Examination (IPDE) is a semistructured clinical interview compatible with the International Classification of Diseases, Tenth Revision , and the DMS-III-R classification systems. This is the first report of the results of a field trial to investigate the feasibility of using the IPDE to assess personality disorders worldwide. Methods: The IPDE was administered by 58 psychiatrists and clinical psychologists to 716 patients enrolled in clinical facilities at 14 participating centers in 11 countries in North America, Europe, Africa, and Asia. To determine interrater reliability, 141 of the IPDEs (20%) were independently rated by a silent observer. To determine temporal stability, 243 patients (34%) were reexamined after an average interval of 6 months. Results: The IPDE proved acceptable to clinicians and demonstrated an interrater reliability and temporal stability roughly similar to instruments used to diagnose the psychoses, mood, anxiety, and substance use disorders. Conclusion: It is possible to assess personality disorders with reasonably good reliability in different nations, languages, and cultures using a semistructured clinical interview that experienced clinicians find relevant, meaningful, and user-friendly.

The Effects of Television Violence on Antisocial Behavior: A Meta-Analysis.

Abstract: A meta-analysis is performed on studies pertaining to the effect of television violence on aggressive behavior. Partitioning by research design, viewer attributes, treatment and exposure variables, and type of antisocial behavior, allows one to interpret computed effect sizes for each of the variables in the partitions. We find a positive and significant correlation between television violence and aggressive behavior, albeit to varying degrees depending on the particular research question. According to research design, we find ZFisher values ranging from .19 for survey to .40 for laboratory experiments. Erotica emerges as a strong factor even when it is not accompanied by portrayal of violence. Additionally, the effect of television violence on the antisocial behavior of boys and girls is found to be marginally equal in surveys. A host of tests are performed to solidify these, and further results. Substantive interpretation is provided as well.

Enhanced aggressive behavior in mice lacking 5-HT1B receptor

Abstract: The neuromodulator serotonin (5-hydroxytryptamine, 5-HT) has been associated with mood disorders such as depression, anxiety, and impulsive violence. To define the contribution of 5-HT receptor subtypes to behavior, mutant mice lacking the 5-HT1B receptor were generated by homologous recombination. These mice did not exhibit any obvious developmental or behavioral defects. However, the hyperlocomotor effect of the 5-HT1A/1B agonist RU24969 was absent in mutant mice, indicating that this effect is mediated by 5-HT1B receptors. Moreover, when confronted with an intruder, mutant mice attacked the intruder faster and more intensely than did wild-type mice, suggesting the participation of 5-HT1B receptors in aggressive behavior.

Major Depression in Community Adolescents: Age at Onset, Episode Duration, and Time to Recurrence

Abstract: Objective This paper presents retrospective and prospective data regarding time course parameters of major depressive disorder (MDD) in community adolescents (14 to 18 years old): time to onset and recovery and, among those who recovered, time to recurrence. Method Diagnostic interviews were conducted with 1,508 randomly selected high school students. Three hundred sixty-two had experienced at least one past or current episode of MDD. Results Mean age at onset of first episode was 14.9 (SD = 2.8). Early MDD onset was associated with female gender and suicidal ideation. MDD episode duration ranged from 2 to 520 weeks, with a mean of 26.4 weeks (SE = 3.3) and a median of 8.0 weeks. Longer episodes were observed in those whose depression occurred early (at or before age 15), whose depression had been accompanied by suicidal ideation, and for whom treatment was sought. Of the adolescents who recovered, 5% relapsed within 6 months, 12% within 1 year, and approximately 33% within 4 years. Shorter time to recurrence was associated with prior suicidal ideation and attempt and with later first onset. Conclusions Risk of MDD is low in childhood, increasing substantially with adolescence. The majority of episodes in community adolescents are relatively brief, although the risk of recurrence is substantial. Suicidal behaviors are important mediators of episode duration and of recurrence.

Role of consciousness and accessibility of death-related thoughts in mortality salience effects.

Abstract: On the basis of terror management theory, research has shown that subtle mortality salience inductions engender increased prejudice, nationalism, and intergroup bias. Study 1 replicated this effect (increased preference for a pro-U.S. author over an anti-U.S. author) and found weaker effects when Ss are led to think more deeply about mortality or about the death of a loved one. Study 2 showed that this effect is not produced by thoughts of non-death-related aversive events. Studies 2 and 3 demonstrated that this effect occurs only if Ss are distracted from mortality salience before assessment of its effects. Study 4 revealed that although the accessibility of death-related thoughts does not increase immediately after mortality salience, it does increase after Ss are distracted from mortality salience. These findings suggest that mortality salience effects are unique to thoughts of death and occur primarily when such thoughts are highly accessible but outside of consciousness. Language: en

Physiological factors associated with falls in older community-dwelling women

Abstract: OBJECTIVE: To determine the prevalence of impaired vision, peripheral sensation, lower limb muscle strength, reaction time, and balance in a large community-dwelling population of women aged 65 years and over, and to determine whether impaired performances in these tests are associated with falls. DESIGN: One-year prospective study. SETTING: Conducted as part of the Randwick Falls and Fractures Study, in Sydney, Australia. PARTICIPANTS: Four hundred fourteen women aged 65 to 99 years (mean age 73.7 years, SD = 6.3) were randomly selected from the community; 341 of these women were included in the 1-year prospective study. MAIN RESULTS: The prevalence of impairment in all tests increased with age. In the year following assessment, 207 subjects (60.7%) experienced no falls, 63 subjects (18.5%) fell one time only, and 71 subjects (20.8%) fell on two or more occasions. After controlling for age, multiple falling was associated with low contrast visual acuity and contrast sensitivity, poor vibration sense and proprioception, reduced lower limb strength, slow reaction time, and impaired balance, as indicated by four sway tests and two clinical stability measures. Discriminant function analysis identified visual contrast sensitivity, proprioception in the lower limbs, quadriceps strength, reaction time, and sway on a compliant (foam rubber) surface with the eyes open as the variables that significantly discriminated between subjects who experienced multiple falls and subjects who experienced no falls or one fall only (Wilks' lambda = 0.73 (P < 0.001), canonical correlation = 0.52). This procedure correctly classified 75% of subjects into multiple faller or nonmultiple faller groups. CONCLUSIONS: These findings support previous results conducted in retirement village and institutional settings and indicate that the test procedure aids in the identification of older community-dwelling women at risk of falls.

Current information on the scope and nature of child sexual abuse.

Abstract: Approximately 150,000 confirmed cases of child sexual abuse were reported to child welfare authorities in the United States during 1993. This number represents about 15% of the more than one million confirmed cases of all child abuse and neglect. But the true scope of this problem is better reflected in retrospective surveys of adults, and this article summarizes data from 19 of these surveys. Considerable evidence exists to show that at least 20% of American women and 5% to 10% of American men experienced some form of sexual abuse as children. The rates are somewhat lower among people born before World War II, but there is little evidence of a dramatic increase for recent generations. The studies provide little evidence that race or socioeconomic circumstances are major risk factors. They do show elevated risk for children who experienced parental inadequacy, unavailability, conflict, harsh punishment, and emotional deprivation. Adult retrospective studies are also good sources of information about the characteristics of abuse. Most sexual abuse is committed by men (90%) and by persons known to the child (70% to 90%), with family members constituting one-third to one-half of the perpetrators against girls and 10% to 20% of the perpetrators against boys. Family members constitute a higher percentage of the perpetrators in child protective agency cases because the mandate of these agencies generally precludes their involvement in extrafamily abuse. Around 20% to 25% of child sexual abuse cases involve penetration or oral-genital contact. The peak age of vulnerability is between 7 and 13. Studies of the criminal justice processing of sexual abusers suggest that, compared with other violent criminals, slightly fewer are prosecuted, but of those prosecuted, slightly more are convicted. Studies conducted in the 1980s also showed that, once convicted, relatively few sexual abusers receive sentences longer than one year, while 32% to 46% serve no jail time. Overall, there is little evidence to suggest that either the child welfare system or the criminal justice system abandons its usual standards of operation and acts hysterically when confronted with sexual abuse. Language: en