Genotype modulates prenatal stress effects on aggression in male and female mice

Prenatal stress (heat and restraint) significantly increased postpartum aggression (proportion of animals fighting and/or the intensity of the behavior) in C57BL/6J female mice and reduced the behavior in DBA/2J females. For intermale aggression, prenatal stress increased the behavior (intensity of aggression) in C57BL/6J males but did not affect aggressive behavior in DBA/2J animals. Infanticidal behavior (the killing of young) exhibited by male mice was not influenced by prenatal stress in either strain. Relative anogenital distance measurements in neonates at birth did not serve as a reliable predictor of strain variation in prenatal stress effects. Prenatal stress did not influence this measure of prenatal androgen exposure in DBA/2J or C57BL/6J females. For males, prenatal stress elevated relative anogenital distance in C57BL/6J mice and decreased this measure in DBA/2J animals. Prenatal stress effects on aggressive behavior in male and female mice therefore depend upon genotype. Strain-dependent differences may be modulated by differences in endocrine reactivity to prenatal stress/and or differential central neural tissue sensitivity to hormones.     

Schizophrene Patienten der forensischen Psychiatrie im Vergleich zu schizophrenen Patienten der Allgemeinpsychiatrie

Background

The number of schizophrenic patients admitted to forensic hospitals according to section 63 of the German Criminal Code has increased continuously over the past years. Some researchers assume that these forensic patients form a group of patients with very complex mental disorders, a number of risk factors and insufficient pretreatment in general psychiatry. This study aimed to identify differences regarding the history of treatment of forensic and general psychiatric patients diagnosed with schizophrenia.

Method

The matched samples included 72 male patients from forensic wards and 72 male patients from general psychiatric institutions diagnosed with schizophrenia. The history of psychiatric treatment was reconstructed by interviewing the patients as well as outpatient psychiatrists and patients’ legal custodians and by analyzing patient medical records.

Results

In contrast to the general psychiatric patients, prior to admission forensic patients were less integrated into psychiatric care and showed a lower rate of treatment compliance. They also showed a higher rate of previous compulsory treatment because of aggressive behavior towards other persons as well as higher rates of treatment difficulties and violent behavior during previous inpatient treatment. Furthermore, forensic patients had a higher number of previous criminal convictions and had been convicted more often for violent offences. With regard to other relevant risk factors (e.g. comorbid substance abuse disorder, age, education, conduct disorder, antisocial personality disorder, previous exposure to violent and abusive behavior) the two patient groups were, however, comparable.

Conclusions

Regarding schizophrenic patients with comorbid substance abuse disorders, previous violent delinquency and violent behavior during previous inpatient treatment, an intensive outpatient aftercare should be arranged before they are discharged from general psychiatric institutions.     

On the gender differential use of listener responsiveness

It is argued that claims of gender differences in back channel behavior should not be uncritically accepted; there are limitations in previous research that make such acceptance questionable. The frequency of back channel behavior was examined over a portion of the early life span (Grades 4 and 9, and college). Twenty-minute structured conversations of 90 dyads (30 male, 30 female, and 30 mixed gender) were scored for eight types of back channels. There was a nonsignificant dyad gender effect for all measures, indicating that back channel frequency did not vary across dyads of different gender composition. The Age × Dyad Gender interaction was significant for only one of the eight back channel types, indicating that age had little effect on the gender-related use of back channel behavior. Although females produced more of some types of back channels than males, there was no difference in back channel frequency between males and females in opposite-gender interaction for any of the eight measures. We conclude that wholesale acceptance of gender differences in back channel behavior is not warranted.     

Sex differences in acting out chronic undifferentiated schizophrenics

29 male and 21 female chronic undifferentiated schizophrenics were classified as aggressive or nonaggressive on items of a behaviorally anchored checklist completed by ward personnel plus adjunctive measures of behavior during institutionalization. Women were rated as significantly more aggressive than men. The women engaged in more hostile acts, destroyed more property, were more verbally abusive, and were more uncooperative with staff and other patients than men. The results are discussed in terms of possible sex differences in diagnosis, severity of symptoms, age of onset, and admission/discharge practices.     

Music and aggression: the impact of sexual-aggressive song lyrics on aggression-related thoughts, emotions, and behavior toward the same and the opposite sex

Three studies examined the impact of sexual-aggressive song lyrics on aggressive thoughts, emotions, and behavior toward the same and the opposite sex. In Study 1, the authors directly manipulated whether male or female participants listened to misogynous or neutral song lyrics and measured actual aggressive behavior. Male participants who were exposed to misogynous song lyrics administered more hot chili sauce to a female than to a male confederate. Study 2 shed some light on the underlying psychological processes: Male participants who heard misogynous song lyrics recalled more negative attributes of women and reported more feelings of vengeance than when they heard neutral song lyrics. In addition, men-hating song lyrics had a similar effect on aggression-related responses of female participants toward men. Finally, Study 3 replicated the findings of the previous two studies with an alternative measure of aggressive behavior as well as a more subtle measure of aggressive cognitions. The results are discussed in the framework of the General Aggression Model.     

College Students’ Video Game Participation and Perceptions: Gender Differences and Implications

As growing numbers of youth in the United States play video games, potential effects of game playing are being considered. We focused on gender-related aspects of gaming in a study of 206 college students. Men were significantly more likely than women to play video games two or more hours a week and to indicate that video game playing interfered with sleeping and with class preparation. A greater proportion of women than men complained about the amount of time their significant other played video games. Participants rated female video game characters as significantly more helpless and sexually provocative than male characters and as less likely to be strong and aggressive. Gender differences in participation and character portrayals potentially impact the lives of youth in a variety of ways.     

Is it emotion or is it stress? Gender stereotypes and the perception of subjective experience

Two studies of college undergraduates (ns = 95 and 92, primarily non-Hispanic whites and Asian Americans) investigated gender stereotypes of stress and emotion, as well as variables that influence the perception of gender-related differences. Study 1 assessed how gender stereotypes differ from the self-reports of men and women. When asked to choose a label for the subjective experience of the average man and the average woman in a series of problematic hypothetical situations, participants generally tended to believe that the average female would feel ‘emotional,” but that the average male would feel “stressed.” By contrast, the label participants chose to describe their own subjective experience was not significantly affected by their gender. In addition, participants believed the average woman and man differed more in the intensity of their emotions than in the intensity of their stress, a belief contradicted by their own self-reports. Results of Study 2 indicated that gender-related differences in estimations of stress and emotion for the self were reduced or eliminated when specific information about experience-eliciting situations was provided. We would like to thank Matthew Dank for his help in preparing the stimulus materials.     

Verbal aggressiveness and state anxiety of volleyball players and coaches

The purpose of the present study was to examine the relation of verbal aggressiveness and state anxiety (somatic, cognitive, and self-confidence) in sports settings based on the ratings by volleyball coaches and their athletes. The sample consisted of volleyball athletes (n=208; 98 men and 110 women) and their coaches (n=20; 16 men and 4 women). Analysis showed that male volleyball players rated somatic anxiety higher and were more affected by the verbal aggressiveness of their coaches than female volleyball players. No mean differences were significant for male and female coaches on somatic or cognitive anxiety, self-confidence, or verbal aggressiveness. Also, correlation between subscale scores for male and female volleyball players and coaches was found. The correlations of verbal aggressiveness with self-confidence and anxiety were positive for these athletes, leading them to better behavior. This relationship needs further examination in sport settings.     

Sex differences in student dominance behavior in female and male professors' classrooms

Measures of verbal participation and interaction among graduate students provided a comparison of male and female dominance behavior in the classroom, and measures of the contextual effect of sex of professor provided further data on the interrelatedness of sex, status, and dominance behavior. Male students were found to exhibit significantly more aggressiveness (interruptive behavior) than female students in both male and female professors' classes, although significantly more male aggressiveness occurred in female professors' classes than in male professors classes. Male students were significantly more assertive (frequency and duration of speech) in female professors' classes only. In student-to-student interaction, aggressiveness was predominantly exchanged between sexes rather than among same-sex members.The author would like to thank Julie Parks and Joanie Rubin for their help with this research.     

Witnessed aggression: influence of an observer's sex and values on aggressive responding.

Two experiments investigated the effects of the presence of an observer on aggressive responding. In one experiment, male subjects observed by a male aggressed more than those observed by a female. When the male observer was removed from the situation, subjects' level of aggressiveness more closely matched the level manifested by the opponent. The removal of the female observer had little effect on the subjects' behavior. In the second experiment, the male or female observer of the subject's behavior was disguised as a member of an organization with explicit values (aggressive or pacifistic) regarding the use of aggression. In this case, significant differences in aggression were associated with the observer's values but not the observer's sex. Following the departure of the observer, the shock settings of subjects in the two aggressive-value observer groups showed a signifcant decrease. The average shock setting of subjects in the two pacifistic-value observer groups remained at about the same level. In sum, the results indicated that the subjects' aggressive behavior was apparently a function of their expectations of approval for such behavior, based on the inferred or explicit values of the observer. The results were further discussed in terms of social learning theory.     

A ten-year prospective study of aggression in a special secure unit for dangerous patients

In a 10-year prospective study inpatient aggression was investigated in a Norwegian special secure unit covering a well-defined catchment area with a population of 240,000. The seven bed special secure unit receives dangerous, psychotic patients for long-term treatment. Only 19 patients were treated during the ten-year study lasting from 1 April 1987 to 1 April 1997. Incidents of aggressive behavior were recorded on the Report Form for Aggressive Episodes by the nursing staff. The study aimed to identify, classify and measure the occurrence of aggressive behavior, as well as the relative frequency of events preceding such behavior. A total of 2021 incidents of aggressive behavior were recorded. Seventy-five per cent of the aggressive acts were verbal or physical threats, while the remaining 25% were physical assaults directed at other persons. Four patients accounted for about 80% of the aggressive encounters. Nursing staff were victims in about 90% of the incidents. Serious physical injury was extremely rare. Situations pertaining to limit-setting and problems of communication accounted for approximately 90% of the precipitants of aggressive behavior. There were no sex differences regarding the occurrence of aggressive behavior.     

Compliance and Satisfaction With Physician-Patient Communication An Expectancy Theory Interpretation of Gender Differences

This pair of studies sought to apply the explanatory calculus of expectancy theory to examine patient compliance and satisfaction with physicians’ instructions. Study 1 analyzed the differential expectations of patients based on gender of the physician. Results indicated that female physicians are expected to use instrumentally unaggressive strategies while male physicians are expected to use strategies that fall in the mid-range of a verbal aggression continuum. There were no differences in expectations based on the gender of patients. The second study manipulated physician communication and physician gender to predict an interaction such that when male physicians deviate from moderately aggressive, direction-giving strategies, using either more affiliative tactics or more instrumentally aggressive strategies, compliance increases. It was also predicted that affective satisfaction with male physicians would increase with increased use of affiliative, nonaggressive compliance-gaining messages. Based on expectancy theory, an inverse linear relationship between the use of instrumental verbal aggression and compliance and affective satisfaction was predicted for female physicians. Results supported the posited interaction. Implications for further refinement of expectancy theory are discussed, and practical implications for physician-patient communication in clinical situations are offered.     

Gender-related effects in the perception of anger expression

The purpose of the study was to investigate the influence of sex of stimulus person, sex type of subject, and sex of subject on the social perception of anger expression. One hundred and sixty-six female and 100 male subjects completed a questionnaire that consisted of 10 vignettes depicting the expression of anger by either a female or a male stimulus person. For each vignette, subjects rated the psychological balance, expected frequency of behavior, perceived degree of anger, and appropriateness of behavior. Overall, female stimulus persons were rated higher on all dependent measures, but only male raters significantly differentiated between male and female stimulus persons. Generally, female subjects gave higher ratings, but viewed angry behavior as less appropriate than did male subjects. Ratings were also found to be related to subjects' scores on Extended Personal Attributes Questionnaire scales that involved socially undesirable traits. Post hoc analysis indicated that the type of anger response (“aggressive” or “nonaggressive”) was also an important variable, especially for the female subjects.     

Ethnic Differences in Parents' Attitudes toward Girls' Use of Aggression

Few studies have attempted to explain ethnic differences in female aggression. The degree to which ethnic differences exist in the influence of parents' approval of aggression on their preadolescent daughters' use of physical, verbal, and relational aggression was explored in a sample of 97 parent-child dyads. Results indicate that European American parents were more disapproving of their daughters' aggressive behavior than were African American parents. Parents' attitude toward aggression was predictive of European American girls' use of physical and verbal aggression and African American girls' use of relational aggression. Implications for aggression prevention and intervention for girls are discussed.     

The effects of token reinforcement and feedback on the delusional verbal behavior of chronic paranoid schizophrenics

Prior research with token reinforcement in the psychiatric population has been directed at work adjustment, more than at major symptomatic behaviors. The purpose of the present research, on the other hand, was to investigate the effects of feedback and token reinforcement on the modification of delusional verbal behavior in chronic psychotics. Six male and four female paranoid schizophrenic patients participated in the study. The results indicated that the effects of feedback were effective about half the time in reducing percentage delusional talk, but in at least three cases produced adverse reactions. Token reinforcement, however, showed more consistency and reduced the percentage of delusional verbal behavior in seven of the nine subjects exposed to this procedure. The effects of both feedback and token reinforcement were quite specific to the environment in which they were applied and showed little generalization to other situations. It would appear that using token reinforcement can reduce the percentage delusional speech of chronic paranoid schizophrenics.     

A male advantage for spatial and object but not verbal working memory using the n-back task

Sex-related differences have been reported for performance and neural substrates on some working memory measures that carry a high cognitive load, including the popular n-back neuroimaging paradigm. Despite some evidence of a sex effect on the task, the influence of sex on performance represents a potential confound in neuroimaging research. The present study investigated sex-related differences in verbal, spatial, and common object versions of the high cognitive load "n-back" working memory task. Eighteen male and 18 female undergraduates completed all 3 versions of the task. A mixed ANOVA, with Sex (male and female) as the between-subjects factor and Condition (verbal, spatial, and object) as the within-subjects repeated measure revealed that males were significantly more accurate than females on the spatial and object versions of the n-back task and performed equivalently to females on the verbal version of the task. Although the expected female advantage for verbal working memory was not found using this effortful n-back task, these results support a male advantage for high cognitive load spatial and object working memory. Future research should take into account the influence of sex on performance of the n-back task, and examine sex-related differences in working memory using other paradigms.     

The Kent-Rosanoff Word Association: I. New Frequencies for Ages 18–21 and a Comparison with Kent-Rosanoff Frequencies

Imitative behavior was studied with the use of 36 kindergarten children who were either reinforced or not reinforced for imitative behavior prior to observing a male model exhibit aggressive behaviors. The children were tested for imitative aggressive behaviors in an eight-minute free-play situation, by means of a five-category rating scale. The results revealed that the reinforced group emitted significant more physical, verbal, and nonimitative aggression than the nonreinforced group. A second test examined the retention of the model's aggressive behavior under an incentive condition. The incentive condition diminished the initial differences found in the first test, revealing a nonsignificant difference between the reinforced and nonreinforced groups. Hence, the study provided support for both the “contiguity” and “generalized imitation” theories of social modeling.