Gordon W. Russell
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780195189599
- eISBN:
- 9780199868445
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195189599.003.0002
- Subject:
- Psychology, Social Psychology
This chapter provides a brief background on the nature of personality traits and what is required to establish their validity. The popular Aggression Questionnaire is singled out and described in ...
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This chapter provides a brief background on the nature of personality traits and what is required to establish their validity. The popular Aggression Questionnaire is singled out and described in some detail in regard to its relationships with a number of other personality variables. Also highlighted are a number of personality theories including the macho and Machiavellian personality each having special relevance for sports aggression. The strength of one's identification with an athlete or sports team is similarly shown to be predictive of aggression. The question of the value of training in the martial arts as a means of reducing the student's aggression is addressed against the background of existing research. Biological influences including sex differences, chromosomes, and testosterone are examined with respect to aggression. The question of parallels between fighting fish and a schoolyard fight is raised in a concluding section.Less
This chapter provides a brief background on the nature of personality traits and what is required to establish their validity. The popular Aggression Questionnaire is singled out and described in some detail in regard to its relationships with a number of other personality variables. Also highlighted are a number of personality theories including the macho and Machiavellian personality each having special relevance for sports aggression. The strength of one's identification with an athlete or sports team is similarly shown to be predictive of aggression. The question of the value of training in the martial arts as a means of reducing the student's aggression is addressed against the background of existing research. Biological influences including sex differences, chromosomes, and testosterone are examined with respect to aggression. The question of parallels between fighting fish and a schoolyard fight is raised in a concluding section.
Gabriel Horn
- Published in print:
- 1985
- Published Online:
- January 2008
- ISBN:
- 9780198521563
- eISBN:
- 9780191706578
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198521563.003.0009
- Subject:
- Psychology, Cognitive Psychology
This chapter reviews evidence that activity in the sensory pathways is insufficient for information storage. The roles of noradrenaline and testosterone in imprinting processes are analyzed. The ...
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This chapter reviews evidence that activity in the sensory pathways is insufficient for information storage. The roles of noradrenaline and testosterone in imprinting processes are analyzed. The concentration of noradrenaline in parts of the forebrain, including the IMHV, appears to limit acquisition particularly in chicks trained on the box. For fowl-trained chicks, preference for the jungle-fowl was associated with testosterone concentration in the plasma. The results suggest that at least some of the neural mechanisms underlying the preference for the box and for the fowl, respectively, are subject to different physiological constraints.Less
This chapter reviews evidence that activity in the sensory pathways is insufficient for information storage. The roles of noradrenaline and testosterone in imprinting processes are analyzed. The concentration of noradrenaline in parts of the forebrain, including the IMHV, appears to limit acquisition particularly in chicks trained on the box. For fowl-trained chicks, preference for the jungle-fowl was associated with testosterone concentration in the plasma. The results suggest that at least some of the neural mechanisms underlying the preference for the box and for the fowl, respectively, are subject to different physiological constraints.
Randy J. Nelson (ed.)
- Published in print:
- 2005
- Published Online:
- May 2009
- ISBN:
- 9780195168761
- eISBN:
- 9780199865444
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195168761.001.0001
- Subject:
- Neuroscience, Behavioral Neuroscience, Neuroendocrine and Autonomic
The primary goal of this book is to summarize and synthesize recent advances in the biological study of aggression. Other than maternal aggression, most aggressive encounters among human and ...
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The primary goal of this book is to summarize and synthesize recent advances in the biological study of aggression. Other than maternal aggression, most aggressive encounters among human and non-human animals represent a male proclivity; thus, most of the research in this book describes and discusses studies using the most appropriate murine model: testosterone-dependent offensive inter-male aggression, which is typically measured in resident-intruder or isolation-induced aggression tests. The research emphasizes various molecules that have been linked to aggression tests. It also emphasizes various molecules that have been linked to aggression by the latest gene-targeting and pharmacological techniques. Although the evidence continues to point to androgens and serotonin (5-HT) as major hormonal and neurotransmitter factors in aggressive behavior, recent work with GABA, dopamine, vasopressin, and other factors, such as nitric oxide, has revealed significant interactions with the neural circuitry underlying aggression.Less
The primary goal of this book is to summarize and synthesize recent advances in the biological study of aggression. Other than maternal aggression, most aggressive encounters among human and non-human animals represent a male proclivity; thus, most of the research in this book describes and discusses studies using the most appropriate murine model: testosterone-dependent offensive inter-male aggression, which is typically measured in resident-intruder or isolation-induced aggression tests. The research emphasizes various molecules that have been linked to aggression tests. It also emphasizes various molecules that have been linked to aggression by the latest gene-targeting and pharmacological techniques. Although the evidence continues to point to androgens and serotonin (5-HT) as major hormonal and neurotransmitter factors in aggressive behavior, recent work with GABA, dopamine, vasopressin, and other factors, such as nitric oxide, has revealed significant interactions with the neural circuitry underlying aggression.
Julie L. Hall, Steven J. Stanton, and Oliver C. Schultheiss
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195335156
- eISBN:
- 9780199776955
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195335156.003.0010
- Subject:
- Psychology, Social Psychology
In this chapter we provide an overview of recent research on the biopsychological correlates of implicit motives. We review evidence for a role of gonadal steroids (testosterone and estradiol) as ...
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In this chapter we provide an overview of recent research on the biopsychological correlates of implicit motives. We review evidence for a role of gonadal steroids (testosterone and estradiol) as well as stress axis activation in power motivation arousal and satisfaction/frustration, summarize recent research on the role of progesterone and affiliation motivation, and discuss a possible role for arginine–vasopressin in achievement motivation. We also present findings from brain imaging work that indicate that the needs for power, affiliation, and achievement modulate activity in a core motivational circuit consisting of striatum, amygdala, orbitofrontal cortex, and insula when nonverbal social incentives are processed.Less
In this chapter we provide an overview of recent research on the biopsychological correlates of implicit motives. We review evidence for a role of gonadal steroids (testosterone and estradiol) as well as stress axis activation in power motivation arousal and satisfaction/frustration, summarize recent research on the role of progesterone and affiliation motivation, and discuss a possible role for arginine–vasopressin in achievement motivation. We also present findings from brain imaging work that indicate that the needs for power, affiliation, and achievement modulate activity in a core motivational circuit consisting of striatum, amygdala, orbitofrontal cortex, and insula when nonverbal social incentives are processed.
Craig F. Ferris
- Published in print:
- 2005
- Published Online:
- May 2009
- ISBN:
- 9780195168761
- eISBN:
- 9780199865444
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195168761.003.0007
- Subject:
- Neuroscience, Behavioral Neuroscience, Neuroendocrine and Autonomic
This chapter focuses on two neurochemical signals that control aggression—serotonin (5-hydroxytryptamine, or 5-HT) and vasopressin (VP). 5-HT and VP appear to play significant roles in the regulation ...
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This chapter focuses on two neurochemical signals that control aggression—serotonin (5-hydroxytryptamine, or 5-HT) and vasopressin (VP). 5-HT and VP appear to play significant roles in the regulation of impulsivity and aggression. 5-HT reduces aggressive responding, while VP enhances arousal and aggression in a context-dependent manner. The interaction between the brain and the environment is regulated, in part, by changes in gonadal and adrenal steroids. The stress of social subjugation alters the levels of testosterone and stress hormones, affecting gene transcription and translation. The VP/5-HT systems are sensitive to changes in these steroid hormones linking the neurochemical regulation of aggression to environmental events.Less
This chapter focuses on two neurochemical signals that control aggression—serotonin (5-hydroxytryptamine, or 5-HT) and vasopressin (VP). 5-HT and VP appear to play significant roles in the regulation of impulsivity and aggression. 5-HT reduces aggressive responding, while VP enhances arousal and aggression in a context-dependent manner. The interaction between the brain and the environment is regulated, in part, by changes in gonadal and adrenal steroids. The stress of social subjugation alters the levels of testosterone and stress hormones, affecting gene transcription and translation. The VP/5-HT systems are sensitive to changes in these steroid hormones linking the neurochemical regulation of aggression to environmental events.
Neal G. Simon and Shi-Fang Lu
- Published in print:
- 2005
- Published Online:
- May 2009
- ISBN:
- 9780195168761
- eISBN:
- 9780199865444
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195168761.003.0009
- Subject:
- Neuroscience, Behavioral Neuroscience, Neuroendocrine and Autonomic
This chapter utilizes conspecific, offensive aggression in males and females as model systems to exemplify androgenic influences on aggressive behavior. This form of aggression is a productive ...
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This chapter utilizes conspecific, offensive aggression in males and females as model systems to exemplify androgenic influences on aggressive behavior. This form of aggression is a productive behavior exhibited between same-sex conspecifics; its effects are reflected in dominance status and access to resources.Less
This chapter utilizes conspecific, offensive aggression in males and females as model systems to exemplify androgenic influences on aggressive behavior. This form of aggression is a productive behavior exhibited between same-sex conspecifics; its effects are reflected in dominance status and access to resources.
Ellen D. "Ketterson and Jonathan W. Atwell (eds)
- Published in print:
- 2016
- Published Online:
- September 2016
- ISBN:
- 9780226330778
- eISBN:
- 9780226330808
- Item type:
- book
- Publisher:
- University of Chicago Press
- DOI:
- 10.7208/chicago/9780226330808.001.0001
- Subject:
- Biology, Evolutionary Biology / Genetics
This edited volume applies concepts and approaches from integrative organismal biology and evolutionary biology to a songbird genus, Junco. Among the most common and abundant groups of songbirds in ...
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This edited volume applies concepts and approaches from integrative organismal biology and evolutionary biology to a songbird genus, Junco. Among the most common and abundant groups of songbirds in North America, juncos exhibit stunning phenotypic diversity across their continent-wide range, and they have been the subject of numerous foundational studies in evolution, ecology, and animal behavior for nearly a century. Across its 14 co-authored chapters, the book synthesizes past, present, and future research programs on the role of hormones in life-history trade-offs, sex differences, and the evolution of behavior, as well as research on the junco as a model of avian diversification and speciation. The 19 contributing authors are biologists from 4 countries and 13 institutes or universities who share a keen interest in the junco because of its current and historical role in understanding evolutionary processes, the mechanisms underlying social behaviors, and how animals know when to breed and migrate. All of the contributors have conducted research on the junco, and collectively they provide diverse expertise in behavioral ecology, behavioral neuroendocrinology, biogeography, bird song, conservation biology, ecological genomics, migration biology, physiological ecology, quantitative genetics, seasonality, and urban ecology. The volume is designed to appeal to scholarly audiences and serious amateurs.Less
This edited volume applies concepts and approaches from integrative organismal biology and evolutionary biology to a songbird genus, Junco. Among the most common and abundant groups of songbirds in North America, juncos exhibit stunning phenotypic diversity across their continent-wide range, and they have been the subject of numerous foundational studies in evolution, ecology, and animal behavior for nearly a century. Across its 14 co-authored chapters, the book synthesizes past, present, and future research programs on the role of hormones in life-history trade-offs, sex differences, and the evolution of behavior, as well as research on the junco as a model of avian diversification and speciation. The 19 contributing authors are biologists from 4 countries and 13 institutes or universities who share a keen interest in the junco because of its current and historical role in understanding evolutionary processes, the mechanisms underlying social behaviors, and how animals know when to breed and migrate. All of the contributors have conducted research on the junco, and collectively they provide diverse expertise in behavioral ecology, behavioral neuroendocrinology, biogeography, bird song, conservation biology, ecological genomics, migration biology, physiological ecology, quantitative genetics, seasonality, and urban ecology. The volume is designed to appeal to scholarly audiences and serious amateurs.
William R. Clark and Michael Grunstein
- Published in print:
- 2004
- Published Online:
- April 2010
- ISBN:
- 9780195178005
- eISBN:
- 9780199893331
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195178005.003.0009
- Subject:
- Biology, Evolutionary Biology / Genetics
Aggression is a form of behavior with the goal of causing damage to another individual. Evolutionarily it developed in response to competition for mates or vital resources. In humans aggressive ...
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Aggression is a form of behavior with the goal of causing damage to another individual. Evolutionarily it developed in response to competition for mates or vital resources. In humans aggressive behavior has become more nuanced, but its goals and causes are essentially the same. A genetic basis for aggression is shown in animals by the ability to selectively breed aggressive behavior to produce extremely aggressive strains in individuals. In humans, twin studies have also made clear that aggression has a strong genetic component. The role of the hormone testosterone is certainly involved, although the exact pathways are unclear. Brain levels of the neurotoxin serotonin correlate with aggression, and genetic manipulation of these levels can enhance or reduce aggressive behavior. A role for the neurotransmitter nitrous oxide has been demonstrated to influence aggression in both animals and humans.Less
Aggression is a form of behavior with the goal of causing damage to another individual. Evolutionarily it developed in response to competition for mates or vital resources. In humans aggressive behavior has become more nuanced, but its goals and causes are essentially the same. A genetic basis for aggression is shown in animals by the ability to selectively breed aggressive behavior to produce extremely aggressive strains in individuals. In humans, twin studies have also made clear that aggression has a strong genetic component. The role of the hormone testosterone is certainly involved, although the exact pathways are unclear. Brain levels of the neurotoxin serotonin correlate with aggression, and genetic manipulation of these levels can enhance or reduce aggressive behavior. A role for the neurotransmitter nitrous oxide has been demonstrated to influence aggression in both animals and humans.
Alvaro Morales
- Published in print:
- 2005
- Published Online:
- November 2011
- ISBN:
- 9780198529415
- eISBN:
- 9780191730344
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198529415.003.0013
- Subject:
- Palliative Care, Patient Care and End-of-Life Decision Making, Pain Management and Palliative Pharmacology
This chapter provides current and updated information on the care of the ageing hypogonadal man from diagnosis to treatment options and monitoring. In most cases, these aspects of care are ...
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This chapter provides current and updated information on the care of the ageing hypogonadal man from diagnosis to treatment options and monitoring. In most cases, these aspects of care are straightforward. The informed clinician has the responsibility to either refer appropriately or to manage effectively and safely the patient with late onset hypogonadism (LOH), also known as androgen decline in the ageing male (ADAM). It is important to emphasize that only symptomatic late-onset hypogonadism (SLOH) needs to be treated. The man without sequelae from low levels of serum testosterone requires follow-up but not necessarily androgen replacement or supplementation.Less
This chapter provides current and updated information on the care of the ageing hypogonadal man from diagnosis to treatment options and monitoring. In most cases, these aspects of care are straightforward. The informed clinician has the responsibility to either refer appropriately or to manage effectively and safely the patient with late onset hypogonadism (LOH), also known as androgen decline in the ageing male (ADAM). It is important to emphasize that only symptomatic late-onset hypogonadism (SLOH) needs to be treated. The man without sequelae from low levels of serum testosterone requires follow-up but not necessarily androgen replacement or supplementation.
Richard G. Bribiescas and Peter T. Ellison
- Published in print:
- 2007
- Published Online:
- April 2010
- ISBN:
- 9780199207466
- eISBN:
- 9780191728167
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199207466.003.0007
- Subject:
- Biology, Evolutionary Biology / Genetics
Trade-offs between reproduction and maintenance can compromise health. Male hormones such as testosterone regulate energy allocation between reproductive effort and survival; this is made evident ...
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Trade-offs between reproduction and maintenance can compromise health. Male hormones such as testosterone regulate energy allocation between reproductive effort and survival; this is made evident when immunological challenges cause changes in reproductive hormones. Female hormones adjust energy allocation between investment in ovarian function, somatic investment, and present offspring (lactation), implementing trade-offs between present and future reproduction. Metabolic hormones respond to environmental cues to sequester or liberate energetic resources such as glucose and fat. Mismatch between environmental conditions and the expression of metabolic hormones are likely to underlie variation in obesity and diabetes. Lifetime variation in endogenous reproductive hormones suggests a trade-off between early benefits for reproduction and later costs against survivorship expressed in population differences in the incidence of reproductive tumors, such as breast and prostate cancer.Less
Trade-offs between reproduction and maintenance can compromise health. Male hormones such as testosterone regulate energy allocation between reproductive effort and survival; this is made evident when immunological challenges cause changes in reproductive hormones. Female hormones adjust energy allocation between investment in ovarian function, somatic investment, and present offspring (lactation), implementing trade-offs between present and future reproduction. Metabolic hormones respond to environmental cues to sequester or liberate energetic resources such as glucose and fat. Mismatch between environmental conditions and the expression of metabolic hormones are likely to underlie variation in obesity and diabetes. Lifetime variation in endogenous reproductive hormones suggests a trade-off between early benefits for reproduction and later costs against survivorship expressed in population differences in the incidence of reproductive tumors, such as breast and prostate cancer.
Geoffrey E. Hill
- Published in print:
- 2002
- Published Online:
- April 2010
- ISBN:
- 9780195148480
- eISBN:
- 9780199893683
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195148480.003.0008
- Subject:
- Biology, Ornithology, Evolutionary Biology / Genetics
This chapter explores the relationship between male plumage color and social status. Experiments show that red feather coloration does not function as a signal of status in either the breeding or ...
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This chapter explores the relationship between male plumage color and social status. Experiments show that red feather coloration does not function as a signal of status in either the breeding or non-breeding season. Drabber males are actually socially dominant to brighter red males. Testosterone implants increase male dominance but reduce male feather coloration, perhaps explaining why drabber males are socially dominant.Less
This chapter explores the relationship between male plumage color and social status. Experiments show that red feather coloration does not function as a signal of status in either the breeding or non-breeding season. Drabber males are actually socially dominant to brighter red males. Testosterone implants increase male dominance but reduce male feather coloration, perhaps explaining why drabber males are socially dominant.
Diana Wiedemann, Robert A Barton, and Russell A Hill
- Published in print:
- 2011
- Published Online:
- January 2012
- ISBN:
- 9780199586073
- eISBN:
- 9780191731358
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199586073.003.0018
- Subject:
- Psychology, Evolutionary Psychology, Developmental Psychology
This chapter examines the theoretical and empirical research into evolutionary aspects of four complex issues of human behaviour in sports. We highlight how evolutionary approaches have promoted our ...
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This chapter examines the theoretical and empirical research into evolutionary aspects of four complex issues of human behaviour in sports. We highlight how evolutionary approaches have promoted our understanding of human sports and competition. To begin with, we describe the relationship between sports competitions and testosterone levels and elucidate how winning and losing leads to different, sometimes status-changing, endocrine responses. Secondly, we look at ‘home advantage’ and examine how hormonal and psychological research has aided our understanding of this well-known phenomenon. The next section focuses on possible evolutionary explanations as to why left-handers may have an advantage in physical combat in both traditional and westernized societies. The final section examines colour influences on human behaviour in general and on sports competition in particular, focusing specifically on the significance of the colour red in human competitive interactions. These four themes serve to highlight the value of evolutionary approaches in enhancing and enriching our understanding of human sports competitions.Less
This chapter examines the theoretical and empirical research into evolutionary aspects of four complex issues of human behaviour in sports. We highlight how evolutionary approaches have promoted our understanding of human sports and competition. To begin with, we describe the relationship between sports competitions and testosterone levels and elucidate how winning and losing leads to different, sometimes status-changing, endocrine responses. Secondly, we look at ‘home advantage’ and examine how hormonal and psychological research has aided our understanding of this well-known phenomenon. The next section focuses on possible evolutionary explanations as to why left-handers may have an advantage in physical combat in both traditional and westernized societies. The final section examines colour influences on human behaviour in general and on sports competition in particular, focusing specifically on the significance of the colour red in human competitive interactions. These four themes serve to highlight the value of evolutionary approaches in enhancing and enriching our understanding of human sports competitions.
Anne Campbell
- Published in print:
- 2002
- Published Online:
- April 2010
- ISBN:
- 9780198504986
- eISBN:
- 9780191584879
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198504986.001.0001
- Subject:
- Psychology, Cognitive Psychology
Current theories of evolution portray men as active individuals who forge their way forward through a mix of testosterone-fuelled competition, rivalry, and aggression. But what role is left for women ...
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Current theories of evolution portray men as active individuals who forge their way forward through a mix of testosterone-fuelled competition, rivalry, and aggression. But what role is left for women within such evolutionary thinking? The role women get is that of the passive, weak individual left to ride on the coattails of their male suitors; the default, no testosterone sex interested in just selecting the best male to expand the gene pool. Is it any wonder that feminists are dismissive of such evolutionary approaches? That many have sought to ignore the contribution that evolutionary theory can make to our understanding of women? But have women really just been bit-part actors in the whole story of evolution? Have they not played their own role in ensuring their reproductive success? This book challenges the passive role of women in evolutionary theory and redresses the current bias within evolutionary writing. Guiding through the basics of evolutionary theory, the book proposes that women have forged their own strategic way forward, acting through their own competition, rivalry, indirect aggression, and unfaithfulness, to shape their own destiny. Throwing down a challenge to feminist theories, the book contends that evolutionary theory can indeed teach us plenty about the female mind in particular and evolutionary psychology in general.Less
Current theories of evolution portray men as active individuals who forge their way forward through a mix of testosterone-fuelled competition, rivalry, and aggression. But what role is left for women within such evolutionary thinking? The role women get is that of the passive, weak individual left to ride on the coattails of their male suitors; the default, no testosterone sex interested in just selecting the best male to expand the gene pool. Is it any wonder that feminists are dismissive of such evolutionary approaches? That many have sought to ignore the contribution that evolutionary theory can make to our understanding of women? But have women really just been bit-part actors in the whole story of evolution? Have they not played their own role in ensuring their reproductive success? This book challenges the passive role of women in evolutionary theory and redresses the current bias within evolutionary writing. Guiding through the basics of evolutionary theory, the book proposes that women have forged their own strategic way forward, acting through their own competition, rivalry, indirect aggression, and unfaithfulness, to shape their own destiny. Throwing down a challenge to feminist theories, the book contends that evolutionary theory can indeed teach us plenty about the female mind in particular and evolutionary psychology in general.
Bonnie Auyeung and Simon Baron-Cohen
- Published in print:
- 2013
- Published Online:
- September 2013
- ISBN:
- 9780199692972
- eISBN:
- 9780191758515
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199692972.003.0017
- Subject:
- Psychology, Developmental Psychology
This chapter examines the role of the hormone testosterone in the development of social cognition. Research findings from human studies designed to elucidate the behavioral effects of both prenatal ...
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This chapter examines the role of the hormone testosterone in the development of social cognition. Research findings from human studies designed to elucidate the behavioral effects of both prenatal and postnatal testosterone exposure in children and young adults are summarized. Effects are found to be both time and dose dependent, with exposure to abnormal hormone levels having a limited impact outside the 'critical window' in development. Particular attention is given to the role of prenatal hormone exposure, which appears to be vital for early organization of the brain. In later life, measurements of circulating hormone levels and the administration of testosterone are found to predict behavior, but the effect is thought to be one of 'activation' or 'fine-tuning' of the early organization of the brain. Possible directions for valuable future research are discussed.Less
This chapter examines the role of the hormone testosterone in the development of social cognition. Research findings from human studies designed to elucidate the behavioral effects of both prenatal and postnatal testosterone exposure in children and young adults are summarized. Effects are found to be both time and dose dependent, with exposure to abnormal hormone levels having a limited impact outside the 'critical window' in development. Particular attention is given to the role of prenatal hormone exposure, which appears to be vital for early organization of the brain. In later life, measurements of circulating hormone levels and the administration of testosterone are found to predict behavior, but the effect is thought to be one of 'activation' or 'fine-tuning' of the early organization of the brain. Possible directions for valuable future research are discussed.
P. G. Clifton
- Published in print:
- 1991
- Published Online:
- March 2012
- ISBN:
- 9780198521846
- eISBN:
- 9780191724640
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198521846.003.0019
- Subject:
- Neuroscience, Behavioral Neuroscience
This chapter reviews some studies that have examined the influence of gonadal steroids on the learning of the passive avoidance task, and also examines the relationship between the effects of ...
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This chapter reviews some studies that have examined the influence of gonadal steroids on the learning of the passive avoidance task, and also examines the relationship between the effects of testosterone on passive avoidance tasks and on other tasks and situations. Furthermore, it explores issues that have not, as yet, received much experimental attention. Many effects of the gonadal steroids are sex dependent. Thus testosterone strongly facilitates attack pecking in male chicks but has little effect on attack pecking in females. The rapidity with which testosterone affects performance in the passive avoidance task clearly distinguishes it from actions of steroids that involve genomic interactions. However, a number of gonadal steroids exert rapid effects on neural activity. The underlying neurochemical basis of these effects is not clear.Less
This chapter reviews some studies that have examined the influence of gonadal steroids on the learning of the passive avoidance task, and also examines the relationship between the effects of testosterone on passive avoidance tasks and on other tasks and situations. Furthermore, it explores issues that have not, as yet, received much experimental attention. Many effects of the gonadal steroids are sex dependent. Thus testosterone strongly facilitates attack pecking in male chicks but has little effect on attack pecking in females. The rapidity with which testosterone affects performance in the passive avoidance task clearly distinguishes it from actions of steroids that involve genomic interactions. However, a number of gonadal steroids exert rapid effects on neural activity. The underlying neurochemical basis of these effects is not clear.
Sarah A. Heimovics, H. Bobby Fokidis, and Kiran K. Soma
- Published in print:
- 2012
- Published Online:
- January 2013
- ISBN:
- 9780199841196
- eISBN:
- 9780199979837
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199841196.003.0011
- Subject:
- Neuroscience, Neuroendocrine and Autonomic
Research on free-living songbirds has revealed novel and important insights into the various contexts in which 17β-estradiol (E2) activates aggressive behavior. In the Pacific Northwest, male song ...
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Research on free-living songbirds has revealed novel and important insights into the various contexts in which 17β-estradiol (E2) activates aggressive behavior. In the Pacific Northwest, male song sparrows defend territories during the breeding season (when circulating testosterone levels are elevated) and during the nonbreeding season (when circulating testosterone levels are nondetectable). The ecological context of territorial aggression differs greatly across seasons, but several lines of evidence indicate that both breeding and nonbreeding aggression depend on the conversion of testosterone into E2 by aromatase. Remarkably, there appears to be a seasonal shift in the source of androgen substrate for brain aromatase: from a systemic source (the testes) in the breeding season to a local source (the brain itself) in the nonbreeding season. This seasonal shift may have evolved to reduce the exposure of peripheral tissues and other brain areas to the deleterious effects of testosterone and E2.Less
Research on free-living songbirds has revealed novel and important insights into the various contexts in which 17β-estradiol (E2) activates aggressive behavior. In the Pacific Northwest, male song sparrows defend territories during the breeding season (when circulating testosterone levels are elevated) and during the nonbreeding season (when circulating testosterone levels are nondetectable). The ecological context of territorial aggression differs greatly across seasons, but several lines of evidence indicate that both breeding and nonbreeding aggression depend on the conversion of testosterone into E2 by aromatase. Remarkably, there appears to be a seasonal shift in the source of androgen substrate for brain aromatase: from a systemic source (the testes) in the breeding season to a local source (the brain itself) in the nonbreeding season. This seasonal shift may have evolved to reduce the exposure of peripheral tissues and other brain areas to the deleterious effects of testosterone and E2.
Margaret M. McCarthy, Christopher L. Wright, and Anne T. M. Konkle
- Published in print:
- 2012
- Published Online:
- January 2013
- ISBN:
- 9780199841196
- eISBN:
- 9780199979837
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199841196.003.0016
- Subject:
- Neuroscience, Neuroendocrine and Autonomic
The central role of neuronal aromatase activity in masculinization of the rodent brain has been firmly established for almost 40 years, yet the myriad of mechanisms by which the principal product of ...
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The central role of neuronal aromatase activity in masculinization of the rodent brain has been firmly established for almost 40 years, yet the myriad of mechanisms by which the principal product of aromatization, estradiol, organizes the neural substrate to predispose adult behavior continue to be elucidated. Unexpected roles for inflammatory mediators and components of the immune system in sexual differentiation elucidate novel principles of brain development. Long-standing puzzles associated with female brain development, both feminization and defeminization, are being solved by unexpectedly rapid and developmentally delayed actions of estradiol, respectively. Neurosteroidogenesis in discrete brain regions, culminating with estradiol but possibly beginning with cholesterol, hints at additional roles for aromatization in brain development outside the confounds of the classical organizational/activational hypothesis and affecting cognitive regions such as the cortex, hippocampus, and cerebellum. Collectively, it is clear that we are far from the final chapter in determining how aromatization influences brain and behavior.Less
The central role of neuronal aromatase activity in masculinization of the rodent brain has been firmly established for almost 40 years, yet the myriad of mechanisms by which the principal product of aromatization, estradiol, organizes the neural substrate to predispose adult behavior continue to be elucidated. Unexpected roles for inflammatory mediators and components of the immune system in sexual differentiation elucidate novel principles of brain development. Long-standing puzzles associated with female brain development, both feminization and defeminization, are being solved by unexpectedly rapid and developmentally delayed actions of estradiol, respectively. Neurosteroidogenesis in discrete brain regions, culminating with estradiol but possibly beginning with cholesterol, hints at additional roles for aromatization in brain development outside the confounds of the classical organizational/activational hypothesis and affecting cognitive regions such as the cortex, hippocampus, and cerebellum. Collectively, it is clear that we are far from the final chapter in determining how aromatization influences brain and behavior.
Kelli A. Duncan and Colin J. Saldanha
- Published in print:
- 2012
- Published Online:
- January 2013
- ISBN:
- 9780199841196
- eISBN:
- 9780199979837
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199841196.003.0020
- Subject:
- Neuroscience, Neuroendocrine and Autonomic
In the avian brain, aromatase is constitutive and inducible in neurons and glia respectively. Glial aromatase is rapidly and dramatically upregulated in astroglia (astrocytes and radial glia) ...
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In the avian brain, aromatase is constitutive and inducible in neurons and glia respectively. Glial aromatase is rapidly and dramatically upregulated in astroglia (astrocytes and radial glia) independent of brain region, in response to perturbation of the neuropil. Estrogens, synthesized by induced aromatization in glial cells, are potent mitigators of apoptotic degeneration and may accelerate neuronal replacement following brain damage. Specifically, aromatase inhibition increases, and estradiol replacement decreases secondary degeneration at the site of primary damage in the passerine brain. Indeed, the characteristic wave of secondary degeneration observed in mammals following compromise of the brain, is severely dampened in the passerine brain and is only revealed following inhibition of inducible glial aromatization. Further, the rate of injury-induced neurogenesis is increased in birds receiving estradiol replacement relative to those treated with an aromatase inhibitor alone. This chapter reviews data on the structural and functional consequences of glial aromatization. It highlights emerging data on the signals that invariably accompany brain damage and their potential role as inductive signals for the transcription and translation of the aromatase gene specifically in glial cells. The robust and cell-specific expression of aromatase in the passerine brain continues to provide an excellent model for the study of the provision of estrogens to neural targets with temporal and spatial specificity. In addition to basic scientific questions, passerine songbirds may serve as superb animal models toward understanding clinical syndromes involving brain damage, ischemia/anoxia, and neurodegeneration.Less
In the avian brain, aromatase is constitutive and inducible in neurons and glia respectively. Glial aromatase is rapidly and dramatically upregulated in astroglia (astrocytes and radial glia) independent of brain region, in response to perturbation of the neuropil. Estrogens, synthesized by induced aromatization in glial cells, are potent mitigators of apoptotic degeneration and may accelerate neuronal replacement following brain damage. Specifically, aromatase inhibition increases, and estradiol replacement decreases secondary degeneration at the site of primary damage in the passerine brain. Indeed, the characteristic wave of secondary degeneration observed in mammals following compromise of the brain, is severely dampened in the passerine brain and is only revealed following inhibition of inducible glial aromatization. Further, the rate of injury-induced neurogenesis is increased in birds receiving estradiol replacement relative to those treated with an aromatase inhibitor alone. This chapter reviews data on the structural and functional consequences of glial aromatization. It highlights emerging data on the signals that invariably accompany brain damage and their potential role as inductive signals for the transcription and translation of the aromatase gene specifically in glial cells. The robust and cell-specific expression of aromatase in the passerine brain continues to provide an excellent model for the study of the provision of estrogens to neural targets with temporal and spatial specificity. In addition to basic scientific questions, passerine songbirds may serve as superb animal models toward understanding clinical syndromes involving brain damage, ischemia/anoxia, and neurodegeneration.
Richmond R. Thompson and Lisa A. Mangiamele
- Published in print:
- 2012
- Published Online:
- January 2013
- ISBN:
- 9780199841196
- eISBN:
- 9780199979837
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199841196.003.0026
- Subject:
- Neuroscience, Neuroendocrine and Autonomic
Although estrogens clearly have rapid, nongenomic effects on cell physiology and brain function, only a few animal models have been developed in which the behavioral consequences of those mechanisms ...
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Although estrogens clearly have rapid, nongenomic effects on cell physiology and brain function, only a few animal models have been developed in which the behavioral consequences of those mechanisms have been established. Recently, it was demonstrated that testosterone (T) can rapidly stimulate approach responses toward the visual cues of potential mates in male goldfish through a rapid mechanism (〈1 hour), and that T’s effects depend on its aromatization into estradiol (E2). Sexual stimuli induce surges in circulating T in this species, which this chapter proposes may drive the rapid behavioral effects of E2 by increasing local aromatase substrate. Furthermore, because aromatase is found in high quantities in visual pathways within the goldfish brain, the chapter suggests that these rapid hormonal effects may prime early sensory processes that increase the males’ ability to detect and/or orient towards the visual cues of potential mates. These studies indicate that T exerts rapid effects on behavioral and physiological processes that likely increase reproductive success in competitive breeding conditions.Less
Although estrogens clearly have rapid, nongenomic effects on cell physiology and brain function, only a few animal models have been developed in which the behavioral consequences of those mechanisms have been established. Recently, it was demonstrated that testosterone (T) can rapidly stimulate approach responses toward the visual cues of potential mates in male goldfish through a rapid mechanism (〈1 hour), and that T’s effects depend on its aromatization into estradiol (E2). Sexual stimuli induce surges in circulating T in this species, which this chapter proposes may drive the rapid behavioral effects of E2 by increasing local aromatase substrate. Furthermore, because aromatase is found in high quantities in visual pathways within the goldfish brain, the chapter suggests that these rapid hormonal effects may prime early sensory processes that increase the males’ ability to detect and/or orient towards the visual cues of potential mates. These studies indicate that T exerts rapid effects on behavioral and physiological processes that likely increase reproductive success in competitive breeding conditions.
Colin J. Saldanha, Luke Remage-Healey, and Barney A. Schlinger
- Published in print:
- 2012
- Published Online:
- January 2013
- ISBN:
- 9780199841196
- eISBN:
- 9780199979837
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199841196.003.0006
- Subject:
- Neuroscience, Neuroendocrine and Autonomic
This chapter reviews the contribution of avian studies towards our understanding of the constitutive provision of estrogens within the brain. The chapter first summarizes numerous studies describing ...
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This chapter reviews the contribution of avian studies towards our understanding of the constitutive provision of estrogens within the brain. The chapter first summarizes numerous studies describing the distribution of aromatase across diverse avian taxa. Then this chapter focuses on the novel finding, that of the expression, sexual dimorphism, and behavioral consequence of aromatization within presynaptic boutons of the brain. The compartmentalization of aromatase into presynaptic boutons appears to function as a highly precise form of cellular communication that may combine aspects of chemical and electrical signaling. This synaptocrine aromatization establishes estrogen produced by neural aromatization as both a traditional hormonal signal as well as an acutely regulated neuromodulator, or even neurotransmitter. The distribution, regulation, and function of this novel form of neurohormonal communication is yet another example of the contribution of avian biology towards broadening our understanding of the interactions among hormones, brain, and behavior.Less
This chapter reviews the contribution of avian studies towards our understanding of the constitutive provision of estrogens within the brain. The chapter first summarizes numerous studies describing the distribution of aromatase across diverse avian taxa. Then this chapter focuses on the novel finding, that of the expression, sexual dimorphism, and behavioral consequence of aromatization within presynaptic boutons of the brain. The compartmentalization of aromatase into presynaptic boutons appears to function as a highly precise form of cellular communication that may combine aspects of chemical and electrical signaling. This synaptocrine aromatization establishes estrogen produced by neural aromatization as both a traditional hormonal signal as well as an acutely regulated neuromodulator, or even neurotransmitter. The distribution, regulation, and function of this novel form of neurohormonal communication is yet another example of the contribution of avian biology towards broadening our understanding of the interactions among hormones, brain, and behavior.
