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PubMed1990

Risk factors for aggressive behaviour are of limited value in predicting the violent behaviour of acute involuntarily admitted patients.

Violent behaviour within 8 and 28 days respectively was related by a multivariate statistical procedure to risk factors for aggressive behaviour in an epidemiologically representative sample of 105 acute involuntarily admitted patients. Previous violent behaviour by the patient was found to correlate significantly with aggressive behaviour during the first 8 days of admission, and abuse of drugs other than alcohol was found to correlate significantly with aggressive behaviour during the first 28 days of admission. Determination coefficients were very low, and it is concluded that risk factors associated with aggressive behaviour are of limited value in predicting aggressive behaviour among acute involuntarily admitted inpatients.

Acute Disease↗
PubMed1998

The identification of abnormal behaviour and behavioural problems in stabled horses and their relationship to horse welfare: a comparative review.

Many behaviours in domestic animals, such as the 'stable vices' of horses, are treated because they are considered undesirable for economic or cultural reasons, and not because the activity affects the horse's quality of life. The impact of a behaviour on the human reporter is not a function of its impact on the animal performer, and an understanding of the causes and effects of the particular activity is necessary to assess the costs and benefits of treatment. Where the behaviour is a sign of poor welfare, such as an inadequate environment, treatment can best be achieved by removing these underlying causal factors. Pharmacological or physical prevention of a behaviour can be justified only if the behaviour causes harm to the performer or to others. In these cases, prevention of the behaviour without addressing its causes is no cure and may result in its perseverance in a modified form or the disruption of the animal's ability to adapt to its environment. Where the behavioural 'problem' causes no harm and is not related to poor housing, then the education of the reporter, rather than treatment of the performer, may be the best solution.

Animal Welfare↗
PubMed1995

Blood donation and Ajzen's theory of planned behaviour: an examination of perceived behavioural control.

In spite of the success achieved by the theory of reasoned action, researchers continue to suggest that new components should be added to the original model. Indeed, Ajzen has himself acknowledged that some behaviours may be subject to control problems and thus proposed the theory of planned behaviour to handle behaviours of this kind. This study set out to explore the predictive superiority of the revised theory of planned behaviour by focusing on blood donation, a behavioural domain in which volitional control was thought to be incomplete. It was also the intention to explore the extent to which the belief-based measure of attitude exists as a multidimensional construct. An Ajzen & Fishbein type questionnaire was administered to 141 undergraduate students. Multiple regression analyses provided strong support for the theory of planned behaviour, suggesting that perception of control has an important impact on a person's behavioural motivation. Also, some support for a multidimensional representation of the belief-based measure of attitude was provided.

Adult↗
PubMed2000

Evidence that long-lasting potentiation in limbic circuits mediating defensive behaviour in the right hemisphere underlies pharmacological stressor (FG-7142) induced lasting increases in anxiety-like behaviour: role of benzodiazepine receptors.

The hypothesis that benzodiazepine receptors mediate initiation of lasting behavioural changes induced by FG-7142 was supported in this study. Behavioural changes normally induced by FG-7142 were blocked by prior administration of the competitive benzodiazepine receptor blocker, Flumazenil. When cats were subsequently given FG-7142 alone, the drug produced lasting behavioural changes in species characteristic defensive responses to rodent and cat vocal threat. FG-7142 also induced long-lasting potentiation (LLP) of evoked potentials in a number of efferent pathways from the amygdala in both hemispheres. Flumazenil given prior to FG-7142 blocked LLP in all but one of the amygdala efferent pathways, suggesting benzodiazepine receptor dependence of initiation of LLP. Three physiological changes were most closely correlated with behavioural changes. LLP in the right amygdalo-ventromedial hypothalamic (VMH) and amygdalo-periacqueductal gray (PAG) pathways coincided closely with behavioural changes, as did a reduced threshold for the right amygdalo-VMH evoked potential. Administration of Flumazenil after FG-7142 returned defensive behaviour to pre FG-7142 baseline levels in a drug-dependent manner. At the same time LLP only in the right amygdalo-PAG pathway was reduced by Flumazenil. LLP in other pathways and amygdalo-VMH threshold were unaltered by Flumazenil. Moreover, covariance analyses indicated that increased defensiveness depended solely on LLP in the right amygdalo-PAG. These findings support the view that maintenance of lasting increases in defensive behaviour depend upon LLP of excitatory neural transmission between amygdala and lateral column of the PAG in the right hemisphere. Moreover, FG-7142 may be a useful model of the effects of traumatic stressors on limbic system function in anxiety, especially in view of the recent data in humans implicating right hemispheric function in persisting negative affective states in post-traumatic stress disorder.

Aggression↗
PubMed2003

Personality systems interactions theory and the theory of planned behaviour: evidence that self-regulatory volitional components enhance enactment of studying behaviour.

The role of volitional components specified by personality systems interactions theory in enhancing behavioural prediction was examined in a longitudinal investigation of students' studying. Participants completed measures specified by the theory of planned behaviour and questionnaire measures of 'conscious attention control', 'implicit attention control' and 'self-determination' from the volitional components inventory. Behaviour was assessed 2 weeks later. Regression analyses showed that volitional components increased variance explained in behaviour by 10-18%, after taking into account strength of motivation to study assessed by attitude, subjective norm, perceived behavioural control and intention from the theory of planned behaviour. Moreover, consistent with elements of personality systems interactions theory, moderator effects were obtained. Participants who reported self-determination, conscious attention control and implicit attention control were more likely to enact their intentions. Volitional components were also associated with increased studying among participants who perceived a low subjective norm for studying. Volitional components improved prediction of studying after accounting for past behaviour in the regression models.

Adolescent↗
PubMed1994

Fear of incontinence and its effects on a community-based rehabilitation programme after severe brain injury: successful remediation of escape behaviour using behaviour modification.

The presence of continence problems following severe traumatic brain injury may be attributable to either organic or psychological factors. In the case of the latter this in turn may lead to the development of behaviours that result in avoidance of or escape from rehabilitation activities. In this paper, a single case study is described in which verbalized fear of incontinence prevented participation within a community rehabilitation programme. Assessment suggested that behaviours that led to escape from this programme were being maintained by negative reinforcement through reduction in anxiety associated with this activity. An intervention was implemented using graded exposure and differential reinforcement of incompatible behaviour. Treatment led to a significant reduction in escape behaviour; this had been maintained and consolidated further at 9-month follow-up. However, no change occurred to the client's prompted self-ratings of anxiety. Reasons for the discrepancy between improvement in behaviour but not self-report are discussed. The potential limitations of using cognitive-behavioural therapy with some survivors of severe traumatic brain injury are also discussed. Finally, comments are made concerning the applicability of the treatment techniques described here in the modification of escape and avoidance behaviours that may be acquired following brain injury.

Activities of Daily Living↗
PubMed2000

Is aggressive behaviour influenced by the use of a behaviour rating scale in patients in a psychogeriatric nursing home?

OBJECTIVE: To study the influence of the introduction of a behaviour rating scale on reported incidence and management of aggressive behaviours in patients in a psychogeriatric nursing home. DESIGN: An 8-month prospective cohort intervention study. SETTING: Two wards of a Dutch psychogeriatric nursing home with residents of 65 years and older. PATIENTS: All residents of the two wards were included (N=75). INTERVENTION: Social Dysfunction and Aggression Scale (SDAS) assessed at weekly intervals during 4 months after a 4 months' baseline period. ASSESSMENTS: During 8 months at 2 months' interval the BOP (ie the validated Dutch version of the Stockton Geriatric Rating Scale); frequency of aggressive behaviour reported at daily nursing staff report; mean prescriptions of psychotropic and somatic drugs; number of days a patient was submitted to physically restrictive measures. RESULTS: Eleven patients (N=11) did not complete the study; information on 64 patients was analysed. The frequency of aggressive behaviour reported by the nursing staff increased, while prescriptions of psychotropic drugs decreased. No alteration was found for BOP scores, mean prescriptions of somatic drugs and the use of physically restrictive measures. CONCLUSIONS: The introduction of a behaviour rating scale does influence the reported incidence and management of aggressive behaviour. Prospective intervention studies should include a stabilization phase for measurements prior to any planned trial.

Aged↗
PubMed2005

Cognitive-behavioural training interventions for assisting foster carers in the management of difficult behaviour.

BACKGROUND: The provision of training for foster carers is now seen as an important factor contributing to the successful outcome of foster care placements. It is believed to be associated with enhancing caring attitudes and skills, reducing behaviour problems in foster children, improving relationships between foster carers and child welfare agencies, and decreasing foster carer attrition. Since the late 1960s, foster carer training programs have proliferated, and few of the many published and unpublished training curricula have been systematically assessed and evaluated. The advent of cognitive-behavioural therapy (CBT) and the research evidence demonstrating its effectiveness as a psychotherapeutic treatment of choice, has prompted many working in the social care field to devise CBT-based training programmes. CBT approaches to foster care training derive from a 'skill-based' training format that also seeks to identify and correct problematic thinking patterns that are associated with dysfunctional behaviour by changing and/or challenging maladaptive thoughts and beliefs. OBJECTIVES: To assess the effectiveness of cognitive-behavioural training interventions in improving a) looked-after children's behavioural/relationship problems, b) foster carers' psychological well-being and functioning, c) foster family functioning, d) foster agency outcomes. SEARCH STRATEGY: We searched databases including: CENTRAL (Cochrane Library Issue 2, 2004), MEDLINE (January 1966 to April 2004), EMBASE (January 1980 to April 2004), CINAHL (January 1982 to April 2004), PsycINFO (January 1872 to April 2004), ASSIA (January 1987 to April 2004), LILACS (up to April 2004), ERIC (January 1965 to April 2004), Sociological Abstracts (January 1963 to April 2004), and the National Research Register 2004 (Issue 1). We contacted experts in the field concerning current research. SELECTION CRITERIA: All studies in which participants were foster parents/carers, and who were allocated by random or quasi-random methods to a CBT-based training intervention (in a group and/or one-to-one settings) versus a no-treatment or wait-list control, were selected. DATA COLLECTION AND ANALYSIS: Results from the five eligible trials (total n = 443 ) are reported narratively. Due to the diversity of measures employed, no meta-analysis was performed. MAIN RESULTS: Training interventions evaluated to date appear to have very little effect on outcomes relating to looked-after children, assessed in relation to psychological functioning, extent of behavioural problems and interpersonal functioning. Results relating to foster carer(s) outcomes indicate some improvements in measures of behavioural management skills, attitudes and psychological functioning. Analysis pertaining to fostering agency outcomes did not show any significant results. AUTHORS' CONCLUSIONS: Inconclusive evidence exists about the efficacy of CBT-based training intervention for foster carers. The need for further research in this area is highlighted.

Aggression↗
PubMed1999

The consistency of individual differences in behaviour: temperature effects on antipredator behaviour in garter snakes.

Differences among individuals are necessary for natural selection to occur. The extent and expression of these differences can limit the power of selection to cause evolutionary change. When individuals inconsistently express a trait, selection is less powerful. Labile traits such as behaviour are most likely to be inconsistent in their expression, because of the substantial role of environmental factors in their immediate expression. Previous work has focused on the consistency, or repeatability, of individual behaviour across different environments or within a single environment; little is known about how repeatability within an environment changes across environments. To address this issue, we examined the consistency of antipredator behaviour in juvenile garter snakes in different thermal environments. A group of 59 laboratory-born garter snakes Thamnophis ordinoides, was repeatedly assayed for sprint speed, distance crawled, and number of reversals performed during flight and antipredator display. Antipredator display showed very little variation and could not be analysed. Each individual was tested three times at each of three temperatures chosen to span the range of temperatures that snakes encounter in the field (15, 22.5, 30 degrees C). Temperature had substantial effects on the average expression of each behaviour; snakes crawled more slowly, for shorter distances, and performed fewer reversals at cooler temperatures. Individuals showed significant consistency in their behaviour, and this consistency of expression was not affected by temperature. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1997

Noncoital sexual interactions and problem behaviour among young adolescents: the Norwegian Longitudinal Health Behaviour Study.

This paper focuses on whether early onset of noncoital sexual interactions is best considered in the same paradigm as adolescent problem behaviour. Among adolescents (n = 927) followed longitudinally from age 13 to 15, the interrelationships between noncoital sexual interactions and various problem and conventional behaviours were examined. Early onset of noncoital sexual interactions was related to problem behaviour, and the higher ordered the noncoital sexual interaction was, the more strongly it correlated with measures of problem behaviour. This study provides support for the usefulness of the notion of an underlying factor of proneness to problem behaviours, which is relevant when studying developmental change in terms of accumulation of early noncoital sexual experience. It is suggested that in the construction of countermeasures to prevent the negative consequences of early sexual activities among adolescents, it may be useful to target broader correlates of behaviour.

Adolescent↗
PubMed2001

Acute trazodone and quipazine treatment attenuates apomorphine-induced aggressive behaviour in male rats without major impact on emotional behaviour or monoamine content post mortem.

We have studied the effect of acute trazodone (3--20 mg kg(-1)) and quipazine (1--3 mg kg(-1)) treatment on the apomorphine-induced (1 mg kg(-1), once daily over 2 weeks) aggressive behaviour in male Wistar rats. All doses of trazodone and quipazine tested attenuated the aggressiveness as evidenced by the abolished intensity of aggressive behaviour and increased time of latency before the first attack. The acute trazodone (3--10 mg kg(-1)) or quipazine (1--3 mg kg(-1)) treatment had no or only a minor effect on rat behaviour in the elevated plus-maze, open field, and forced swimming test. Concomitant apomorphine (1 mg kg(-1)) plus trazodone (3 mg kg(-1)), but not apomorphine (1 mg kg(-1)) plus quipazine (1 mg kg(-1)), treatment slowed the development of aggressive behaviour. Repeated apomorphine treatment moderately reduced the dopamine post mortem and increased the DOPAC and HVA contents in striatum. Other monoamines or their metabolites were unchanged. Neither trazodone and quipazine treatment nor forced swimming stress induced any changes in the monoamine contents. In conclusion, our results indicate that acute trazodone and quipazine treatment attenuates the apomorphine-induced aggressive behaviour in male rats, but this phenomenon cannot be implicated in the changes in emotional and motivational behaviour, or in changes of monoamine content post mortem.

Aggression↗
PubMed1996

Behavioural effects of 7-OH-DPAT are solely due to stimulation of dopamine D2 receptors in the shell of the nucleus accumbens; turning behaviour.

The goal of this study was to determine whether the dopamine D3 receptor in limbic structures plays a role in the shell-specific and dopamine-dependent display of turning behaviour in rats. When combined with the dopamine D1 receptor agonist (+/-)-1-phenyl-2,3,4,5-tetrahydro-1 H-3-benzazepine-7,8-diol (SKF-38393, 5 micrograms), the putative dopamine D3 receptor agonist (+/-)-7-hydroxy-N,N-di-n-propyl-2-aminotetralin (7-OH-DPAT, 1, 5 and 10 micrograms) elicited contralateral turning in a dose-dependent manner following unilateral injection into the shell, but not the core, of the nucleus accumbens. The turning pattern displayed was identical to that reported previously after intra-accumbens administration of the cocktail of SKF-38393 and the dopamine D2 receptor agonist quinpirole. The behaviour under study was dose-dependently attenuated by local administration of the dopamine D1 receptor antagonist R(+)-7-chloro-8-hydroxy-3- methyl-I-phroyl-2,3,4,5-tetrahydro-1H-3-benzazepine (SCH 23390: 10 and 100 ng), the dopamine D2 receptor antagonist domperidone (25 and 50 ng) or the dopamine D2/3 receptor antagonist l-sulpiride (5 and 25 ng). Combined blockade of both dopamine D1 and D2 receptors in the shell with a dose of either antagonist alone that produced just a moderate reduction (10 ng SCH 23390 and 50 ng domperidone) completely antagonized the turning behaviour elicited by the cocktail of SKF-38393 and 7-OH-DPAT. Replacing 7-OH-DPAT by another putative dopamine D3 receptor agonist,S(+)-(4aR, 10bR)-3,4,4a,10b-tetrahydro-4-propyl-2H,5H-[1]benzopyrano[4, 3-b]-1, 4-oxazin-9-ol (PD 128,907, 10 micrograms), in the cocktail did produce no turning behaviour at all. It is concluded that mesolimbic dopamine D3 receptors play no role in the dopamine-dependent and shell-specific turning behaviour: the contribution of 7-OH-DPAT in the cocktail of SKF-38393 and 7-OH-DPAT to the display of turning behaviour is solely due to its ability to activate dopamine D2 receptors.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1984

The behavioural effects of RU 24969, a suggested 5-HT1 receptor agonist in rodents and the effect on the behaviour of treatment with antidepressants.

Some behavioural and biochemical consequences of the administration of RU 24969 (5-methoxy-3(1,2,3,6-tetrahydropyridin-4-yl)-1H-indole), a drug which has been shown to be a potent displacing agent at the 5-HT1 binding site, have been studied in mice and rats. In both species RU 24969 produced a dose-dependent increase in locomotor activity. No head-weaving, head-twitching or reciprocal forepaw treading (behaviour suggested to be 5-HT2 receptor mediated) were seen, nor did the body temperature increase p-Chlorophenylalanine did not alter either the behaviour or its intensity. Pretreatment with both methysergide (10 mg/kg) and metergoline (2.5 mg/kg) enhanced the behavioural response in rats, whilst haloperidol (100 micrograms/kg) inhibited the response. Propranolol caused a small and variable decrease in the increase in locomotion induced by RU 24969 in both mice and rats. The drug RU 24969 (10 mg/kg) inhibited the rate of synthesis of 5-HT in rat brain by about 50%. Pretreatment of rats with desmethylimipramine over a longer term or clenbuterol given acutely, treatments known to enhance the behavioural responses of rats to various other 5-HT agonists, did not alter the RU 24969-induced response. Repeated administration of electroconvulsive shock, however, did produce an enhanced locomotor response to RU 24969. The results obtained are consistent with the view that administration of 5-HT agonists, such as quipazine and 5-methoxy-N,N-dimethyltryptamine, produces behaviour that results from stimulation of both 5-HT1 and 5-HT2 receptor populations.

Animals↗
PubMed2006

The resonance frequencies and mode shapes of dental implants: Rigid body behaviour versus bending behaviour. A numerical approach.

The purpose of this study was to evaluate the modal behaviour of the bone-implant-transducer (Osstell) system by means of finite element analyses. The influence of different parameters was determined: (1) the type of implant anchorage being trabecular, cortical, uni-cortical, or bi-cortical, (2) the implant diameter, (3) the length of the implant embedded in the bone, and (4) the bone stiffness. The type of anchorage determines the resulting modal behaviour of the implant-transducer system. A rigid body behaviour was found for a uni-cortical anchoring and for a homogeneous anchoring with low bone stiffness (< or =1000 MPa), whereas a bending behaviour was found for a homogeneous anchoring with a high bone stiffness (> or =5000 MPa) and for a bi-cortical anchorage. The implant dimensions influence the values for the resonance frequencies. Generally, an increase in implant diameter or implant length (in bone) results in higher resonance frequencies. This study also showed that resonance frequencies in case of rigid body behaviour of the implant-transducer system are more sensitive to changes in bone stiffness than resonance frequencies in case of bending behaviour. In conclusion, it seems that the Osstell transducer is suited for the follow-up in time of the stability of an implant, but not for the quantitative comparison of the stability of implants.

Anisotropy↗
PubMed2005

The impact of the transmission dynamics of the HIV/AIDS epidemic on sexual behaviour: a new hypothesis to explain recent increases in risk taking-behaviour among men who have sex with men.

Increases in sexually transmitted infections and related high-risk behaviours have been reported among men who have sex with men (MSM) in industrialised countries when effective antiretroviral therapy against HIV infection has become widely available, in the mid-nineties. The reasons for these increases are not fully understood and often conflicting. Prevention fatigue, relapses to unsafe sex, as well as optimism toward the risk of developing AIDS among people living with HIV are not unique to the era of antiretroviral therapy (ART). This has led researchers to highlight the need to investigate other potential reasons that could explain the increase in high-risk taking following the ART introduction. We put forward the hypothesis that the change in the transmission dynamics of the HIV/AIDS epidemic before and after the introduction of ART has contributed to this change in high-risk behaviour. It is suggested that a decline in sexual risk activities has occurred at the population-level following the initial spread of the HIV/AIDS epidemic because AIDS mortality and severe morbidity disproportionately depleted the pool of high-risk taking individuals. As a result, non-volitional changes may have occurred at the individual-level over time because the depletion of this pool of high-risk individuals made it more difficult for the remaining high-risk taking individuals to find partners to engage in risky sex with. Following its introduction, ART has facilitated the differential replenishment of the pool of individuals willing to engage in high-risk taking behaviours because ART reduces AIDS mortality, and morbidity. Consequently, high-risk taking individuals who had previously reduced their level of risky sex non-volitionally (i.e., as a result of the reduced availability of high-risk partners) were able to resume their initial high-risk practices as the pool of high-risk taking individuals replenished over time. Thus, a fraction of the recently reported increase in high-risk sexual activities may be secondary to the fact that those MSM who were unable to engage in their desired high-risky sexual activities (because of reduced availability) are now able to revert to them as the availability of men willing to engage in risky sexual behaviours increases partly due to ART. Therefore, we suggest that a fraction of the changes in individual behaviour are non-volitional and can be explained by a change in "sexual partner availability" due to the transmission dynamics of HIV/AIDS before and after ART. The hypothesis is formulated and explained using simple social network diagrams and the Theory of Planned Behaviour. We also discuss the implication of this hypothesis for HIV prevention.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Youth risk behaviour in a Chinese population: a territory-wide youth risk behavioural surveillance in Hong Kong.

This cross-sectional study investigated the prevalence rates of different categories of youth risk behaviour by age, sex and parental education. The study population consisted of 26,111 Hong Kong students, aged 10-19 years, recruited from 48 primary (primary grades 4-6) and secondary schools (secondary grades 1-7). Less than one-third of subjects participated in vigorous exercise regularly, about one-third consumed an unhealthy diet frequently, 18% had tried smoking, and 14.5% had seriously considered attempting suicide. Although only 3.4% of students reported experience of sexual intercourse, less than half used a contraceptive device. Older students had higher prevalence rates of health-compromising behaviours than younger students. Female students were more likely to report suicide-related behaviour, attempting weight loss, and non-participation in vigorous physical activities. Students with parents of a lower educational background were more likely to report rarely or never wearing seat belts and bicycle helmets, suicide-related behaviour, smoking, sexual intercourse before 13 years of age, and attempting weight loss. The availability of data on youth health risk behaviours would enable health educators, public health practitioners and clinicians to plan appropriate screening and counselling for risk behaviours in early adolescents.

Adolescent↗
PubMed2001

Sexual behaviour in Britain: partnerships, practices, and HIV risk behaviours.

BACKGROUND: Sexual behaviour is a major determinant of sexual and reproductive health. We did a National Survey of Sexual Attitudes and Lifestyles (Natsal 2000) in 1999-2001 to provide population estimates of behaviour patterns and to compare them with estimates from 1990-91 (Natsal 1990). METHODS: We did a probability sample survey of men and women aged 16-44 years who were resident in Britain, using computer-assisted interviews. Results were compared with data from respondents in Natsal 1990. FINDINGS: We interviewed 11161 respondents (4762 men, 6399 women). Patterns of heterosexual and homosexual partnership varied substantially by age, residence in Greater London, and marital status. In the past 5 years, mean numbers of heterosexual partners were 3.8 (SD 8.2) for men, and 2.4 (SD 4.6) for women; 2.6% (95% CI 2.2-3.1) of both men and women reported homosexual partnerships; and 4.3% (95% CI 3.7-5.0) of men reported paying for sex. In the past year, mean number of new partners varied from 2.04 (SD 8.4) for single men aged 25-34 years to 0.05 (SD 0.3) for married women aged 35-44 years. Prevalence of many reported behaviours had risen compared with data from Natsal 1990. Benefits of greater condom use were offset by increases in reported partners. Changes between surveys were generally greater for women than men and for respondents outside London. INTERPRETATION: Our study provides updated estimates of sexual behaviour patterns. The increased reporting of risky sexual behaviours is consistent with changing cohabitation patterns and rising incidence of sexually transmitted infections. Observed differences between Natsal 1990 and Natsal 2000 are likely to result from a combination of true change and greater willingness to report sensitive behaviours in Natsal 2000 due to improved survey methodology and more tolerant social attitudes.

Adolescent↗