Behavioural effects of androgens in men

A series of studies are presented which attempt to answer specific questions concerning the androgen-behaviour relationship in the adult human male. A critical review of the literature revealed that the androgen-behaviour relationship in the human male has been poorly researched. In particular, unsatisfactory experimental methodology and inexact operational definitions of behaviour have been employed. In the studies presented in this thesis an attempt was made to specifically define dysfunctional states and to carefully monitor the resultant behavioural effects of androgen administration. In the hypogonadal man, a dose-dependent relationship was demonstrated for specific aspects of sexual functioning, in particular self-rated interest in sex and frequency of morning erections appeared to vary with androgen replacement dose. In the eugonadal man, intramuscular depot injections of testosterone were shown to be the best method of overcoming the homeostatic mechanisms and increasing circulating androgen levels in the blood. High dosage testosterone administration acted to increase the level of sexual interest of a group of men whose presenting complaint was loss of libido. This treatment, however, did not result in an increased frequency of sexual activity. High dosage testosterone administration had no behavioural effect, compared with placebo, in a group of eugonadal men presenting with erectile dysfunction. Androgen administration appeared to have a stimulatory effect on the nocturnal erections of a group of hypogonadal men, although androgen withdrawal resulted in differing rates of diminution of nocturnal erectile response. In contrast, androgen administration had no effect on the nocturnal erections of a group of eugonadal men presenting with erectile dysfunction. Androgen administration to hypogonadal and eugonadal men had a general lack of effect on a series of psychometric test scores, which measure various aspects of cognitive functioning and personality. (Previous investigators had proposed that these test scores were correlated with circulating androgen levels). A case study is presented, reporting the lack of behavioural effect of oral testosterone undecanoate administration in an institutionalised hypogonadal man who had previously responded very aggressively to testosterone injections. The implications of these experimental findings are discussed in relation to the results of previous studies

'What if I'm not dead?' - Myth-busting and organ donation

Objectives. In the UK, three people die every day awaiting an organ transplant. To address this, Scotland and England plan to follow Wales and introduce opt-out donor consent. However, emotional barriers, myths and misconceptions may deter potential registrants. Our objectives were to estimate the number of people who plan to opt-out of the donor register and to test if emotional barriers (e.g., medical mistrust) differentiated participants within this group. Finally, in an experimental manipulation, we tested whether intention to donate decreased by making emotional barriers more salient and increased following a widely used myth-busting intervention. Design. Mixed between-within design. Methods. UK residents (n = 1202) were asked whether they would choose; opt-in, deemed consent, or opt-out/not sure if legislation changes to opt-out. Participants also completed measures of donor intentions at baseline, following a 12-item emotional barriers questionnaire and again, following a 9-item myth-busting intervention. Results. Findings indicate that 66.1% of participants selected to opt-in to the donor register, 24.3% selected deemed consent and 9.4% selected opt-out/not sure. Emotional barriers, notably, fears surrounding bodily integrity were significantly elevated in participants who selected opt-out/not sure. Increasing the salience of emotional barriers reduced donor intentions in the opt-out/not sure group. However, dispelling organ donation myths did not increase intention within this group. Conclusions. If opt-out legislation is introduced in Scotland and England, approximately 10% of participants plan to opt-out or are not sure. Dispelling organ donation myths with facts may not be the best method of overcoming emotional barriers and increasing donor intentions for those planning to opt-out

'If I donate my organs it's a gift, if you take them it's theft': a qualitative study of planned donor decisions under opt-out legislation

Background: There is a worldwide shortage of donor organs for transplantation. To overcome this, several countries have introduced an opt-out donor consent system. This system, soon planned for Scotland and England means individuals are automatically deemed to consent for organ donation unless they register an opt-out decision. This study was designed to explore the reasons underpinning donor choices for people who plan to actively opt-in to the register, take no action and be on the register via deemed consent, opt-out, and those who are unsure of their decision. Methods: This study reports the analysis of free-text responses obtained from a large survey of intentions towards opt-out legislation in Scotland, England and Northern Ireland (n = 1202). Of the n = 1202 participants who completed the questionnaire, n = 923 provided a free text response explaining their views. Thematic analysis was used to explore the reasons why participants plan to: opt-in (n = 646), follow deemed consent (n = 205), opt-out (n = 32) and those who were not sure (n = 40) Results: A key theme for people planning to opt-in is that it ensures one’s donor choice is explicitly clear and unequivocal. Some regarded deemed consent as unclear and open to ambiguity, thus actively opting-in was viewed as a way of protecting against family uncertainty and interference. For the deemed consent group, a key theme is that it represents a simple effortless choice. This is important from both a pragmatic time-saving point of view and because it protects ambivalent participants from making a challenging emotive choice about organ donation. Key themes for those planning to opt-out relate to fears around medical mistrust and bodily integrity. Notably, both participants who plan to opt-out and opt-in perceived presumed consent as “authoritarian” and a method of increasing Government control of organs. In response, registering an active decision protected their freedom of choice. Conclusions: The findings highlight the importance of registering deliberate active consent for people who choose opt-in, due to concerns over possible family refusal under deemed consent. These findings could inform the development of communication campaigns that encourage family communication before the implementation of opt-out legislation

If you needed an organ transplant would you have one? The effect of reciprocity priming and mode of delivery on organ donor registration intentions and behaviour

Objective: There are approximately 6,500 people on the UK national transplant waiting list, around 400 of whom die every year. Only 35% of the UK population are currently on the organ donation register. We report 2 studies examining whether a reciprocity prime, in which participants were asked whether they would accept a donated organ, increased organ donation intentions and behaviour.  Design: Between participants, randomized-controlled design.  Methods: In 2 studies, participants who were not currently registered organ donors took part either face-to-face or online, and were randomly allocated to a reciprocity prime or control condition. Following the manipulation they were asked to indicate, on either a paper or online questionnaire, their intention to join the organ donor register. Study 2 was similar to Study 1 but with the addition that after reporting intention, participants were then offered an organ donation information leaflet or the opportunity to click a link for further information (proxy behavioural measure).  Results: In both studies, reciprocity primed participants reported greater intentions to register than controls. However, in Study 2, no effect on donation behaviour was found.  Conclusions: Reciprocal altruism may be a useful tool in increasing intentions to join the organ donor register. Further evaluation is required to determine whether this increase in intention can be translated into organ donation behaviour

Investigating proximate mechanisms and ultimate functions of memory for emotional events

This thesis is an investigation of the proximate mechanisms and ultimate functions of memory for emotional events. The theoretical basis of this Thesis is that in order to reach a full understanding of a biological phenomenon, it is important that both proximate and ultimate (functional) explanations for that phenomenon are explored. Chapters 2 and 3 present an examination of the proximate mechanisms involved in memory consolidation of emotional events. In Chapter 2, three experiments are presented each testing the hypothesis that stress hormone activation immediately following viewing an emotional event enhances memory for that event. Each of the three experiments failed to find an enhancing effect of stress hormone activation on memory consolidation. Chapter 3 describes an investigation into whether the reduced feedback from the body to the brain, which occurs as a result of total spinal cord transection, diminishes the intensity of emotional experience and therefore impairs memory for emotional events. The results of this investigation revealed no differences between spinal cord transection patients and matched control participants in emotional expressivity, emotional awareness and in memory for emotional material. Chapters 4 and 5 explore how memory and emotion may interact differently for males and females and in manner that facilitates their survival and reproduction. Evolutionary theory argues that males should be more concerned than females about threats to their social status, whereas females should be more concerned about threats to their physical appearance and sexual reputation. Chapter 4 describes two experiments testing whether a) males have enhanced emotional arousal and memory for words implying they are of low social status; b) females have enhanced emotional arousal and memory for words implying they are physically unattractive and sexually untrustworthy. The results of these experiments showed that females had enhanced memory for words relating to physical appearance, and partial evidence that males have 2 enhanced memory for words relating to social status. Chapter 5 tests the evolutionary theory that males should be more emotionally aroused and thus have greater memory for cues relating to sexual infidelity (the thought of their partner having sex with another man), whereas females should be more emotionally aroused and have greater memory for cues to emotional infidelity (the thought of their partner forming a close emotional attachment with another woman). It also examines whether relationship status affects emotional arousal and memory for these cues. The results did not find any support for these hypothesised sex difference in memory. However, those ‘currently in a relationship’ did show enhanced emotional arousal to cues to sexual infidelity compared to those ‘currently not in a relationship’. Chapter 6 presents an investigation concerning the evolutionary hypothesis that individuals tend to have enhanced recognition memory for the faces of deceivers or ‘liars’. This chapter describes a study in which participants viewed a series of short video clips of individuals, half of whom were lying, half telling the truth. Participants’ memory for the individuals that appeared in the video clips was tested but there was no evidence of enhanced memory for the faces of ‘liars’. Chapter 7 provides a general discussion of the findings of this thesis. The failure to find an enhancing effect of post learning stress hormone activation on memory for emotional material, and the failure to find an impairment in memory for emotional material in people with total spinal cord transection contradict two established views on the proximate mechanisms involved in emotion, and emotions effect of the brain. How these findings relate to the established mainstream views on emotion and memory are discussed. The findings of studies concerning the functional interaction of memory and emotion presented in this thesis are also discussed in relation to previous research.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Antimicrobial Resistance in Humans and Animals: Rapid Review of Psychological and Behavioral Determinants

A rapid review of current evidence examining psychological issues regarding the use of antibiotics and antimicrobials and resistance to these in both human and animal populations was conducted. Specific areas of interest were studies examining psychological determinants of AMR and interventions which attempt to change behavior with regard to AMR in the general population; animals; and fish, in particular. Although there is some evidence of the effectiveness of behavior change in general human populations, there is limited evidence in farmed animals, with a particular dearth in fish farming. We conclude there is an urgent need for more psychological research to identify major barriers and facilitators to change and evaluate the effectiveness of theory-based interventions aimed at reducing AM use in food production animals, including the promotion of alternatives to AMs, such as vaccination

Disability and physical activity behaviours : an application of theoretical frameworks

Background: The prevalence of disability increases with age; therefore with an aging population, interventions to reduce disability are crucial. This thesis adopts a behavioural conceptualisation of disability. The theoretical frameworks of the International Classification of Functioning, Disability and Health (ICF), the Theory of Planned Behaviour (TPB) and the integrated ICF/TPB model are applied to investigate disability and physical activity (PA) behaviours. The thesis aims to: (1) identify the factors involved in the prioritisation of patients for total joint replacement; (2) classify patient pre-operative expectations of total hip replacement (THR) and investigate the relationship between expectations and recovery after surgery, and; (3) test whether the TPB and theory-based interventions can predict and explain PA within individuals. Method: Five studies were conducted. In the first study, health professionals judged whether the items from two prioritisation tools measured each of the ICF constructs. In the second study, surgeons ranked patient vignettes, which differed by constructs from the integrated model, in order of priority for THR. In the third study, a large cohort of THR patients reported expectations of surgery pre-operatively. Health and functioning were also reported pre-operatively and 1-year post-operatively. The fourth and fifth studies were a series of experimental n-of-1 studies using diary methods assessing TPB cognitions and PA behaviours. Results: There is a lack of agreement between judges in relation to the content of many of the items from prioritisation tools. Behavioural and psychological factors can influence prioritisation for THR. The majority of patient expectations of THR addressed activities and social participation; however, the evidence for a relationship between expectations and recovery was limited. The TPB can predict PA within some individuals but the evidence in support of interventions to increase PA was limited. Discussion: The findings provide important clinical and theoretical implications for understanding disability and physical activity behaviours.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Qualitatively exploring the application of the necessity concerns framework to antenatal physical activity

Background Adherence to physical activity (PA) recommendations during pregnancy is low. A common reason for low adherence is concern of harm to mother and/or baby. The Necessity-Concerns Framework (NCF), is a well-established framework in medicine adherence, however it has not been used to explore adherence to antenatal PA. This study aims to explore (1) what influences pregnant women's PA in the context of the NCF; and (2) if the NCF is an appropriate framework to understand antenatal PA engagement. Methods Semi-structured interviews were conducted with 18 pregnant women in the UK and Ireland (mean gestation 27 weeks). Interviews explored beliefs, experiences, perceived necessities and concerns about PA. Interviews were transcribed verbatim and analysed using thematic framework analysis. Results Five themes were identified as influential to antenatal PA: (1) Perceived benefits and necessity of PA, (2) Concerns regarding antenatal PA, (3) Balancing the necessity and concern, (4) Barriers to antenatal PA, (5) Facilitators of antenatal PA. Women described a number of perceived necessities and concerns regarding antenatal PA. These necessities and concerns were described as being consciously balanced, supporting the NCF. However, a number of additional influences (for example, feelings of nausea and lack of advice and knowledge) seemed to impact antenatal PA engagement before women could consider their perceived necessities and concerns around antenatal PA. Conclusions The Necessity Concerns Framework is a useful framework to help explain how and why women engage with antenatal PA, more specifically why women do and do not engage in antenatal PA at different times during their pregnancy. However, there are a number of other interpersonal and intrapersonal influences on antenatal PA (e.g. physical symptoms, motivation and time), suggesting the NCF alone may be too simplistic to understand and influence complex behaviour such as antenatal PA

Stimulation of the noradrenergic system enhances and blockade reduces memory for emotional material in man

Background. It is clearly established that emotional events tend to be remembered particularly vividly. The neurobiological substrates of this phenomenon are poorly understood. Recently, the noradrenergic system has been implicated in that beta blockade has been shown to reduce significantly the delayed recall of emotional material with matched neutral material being unaffected. Methods. In the present study, 36 healthy young adults were randomly allocated to receive either yohimbine, which stimulates central noradrenergic activity, metoprolol which blocks noradrenergic activity, or matched placebo. The three groups were well matched. All capsules were taken orally, prior to viewing a narrated 11 slide show described a boy being involved in an accident. Results. Yohimbine significantly elevated, and metoprolol reduced mean heart rate during the slide show relative to placebo, thus confirming the efficacy of the pharmacological manipulation. One week later, in a ‘surprise’ test, memory for the slide show was tested. As predicted, yohimbine-treated subjects recalled significantly more and metoprolol subjects fewer slides relative to placebo. This result was confirmed via analysis of multiple-choice recognition memory scores. Conclusions. We conclude that stimulation of the noradrenergic system results in the enhancement and blockade in a reduction of recall and recognition of emotional material in man

Blood and organ donation: health impact, prevalence, correlates, and interventions

Objective: Without a supply of blood, health services could not meet their clinical needs. Similarly, organs for transplantation save and transform lives. Donations are acts of generosity that are traditionally seen as altruistic, and accordingly, interventions to recruit and retain blood and organ donors have focused on altruism. We review the predictors, prevalence and correlates of these two behaviours, how effective interventions have been, and draw common themes. Design: Narrative review. Results: We highlight that both recipients and donors benefit, and as such neither blood nor organ donation is purely altruistic. We also highlight health problems associated with both types of donation. In evaluating interventions, we highlight that a move to an opt-out policy for organ donation may not be the simple fix it is believed to be, and propose interventions to enhance the effectiveness of an opt-in policy (e.g. social media updates). We show that incentives, text messaging, feedback and a focus on prosocial emotions (e.g. ‘warm-glow’, ‘gratitude’) may be effective interventions for both blood and organ donation. Interventions designed to reduce fainting (e.g. water pre-loading) are also effective for blood donation. Conclusions: We conclude that affect is key to understanding both types of donation and in designing effective interventions