Sex differences in the Brain: Fact or Fiction? скачать в хорошем качестве

Sex differences in the Brain: Fact or Fiction?

VideoLectures.Net View the talk in context: http://videolectures.net/bzid2011_mcc... View the complete International Conference Bioscience and Society: Interdependence of processes: http://videolectures.net/bzid2011_lju... Speaker: Margaret M. McCarthy, Departments of Physiology and Pharmacology, University of Maryland School of Medicine License: Creative Commons CC BY-NC-ND 3.0 More information at http://videolectures.net/site/about/ More talks at http://videolectures.net/ Everyone knows and agrees that men and women are different, they look different, dress different, behave different and often seem to think different. What is not agreed upon is why this is so. Is it societal expectations, parental guidance, biological determinism, genetics or some combination thereof? And the answer to the question is not important for mere curiosity, it is fundamental to major issues such as educational policies, health care, job equity and more. Parsing out the contributing role of each variable is exceedingly difficult in humans where we cannot conduct experiments or control for experience and environment. However, in animals we can do exactly that, and we can thereby determine how much nature versus nurture influences the establishment, maintenance and functional significance of sex differences in the brain. The next great challenge is to then determine how what we find in animals applies to humans, and perhaps more importantly, how it doesn't. Sex differences in the brain come in many sizes, shapes and forms. The most robust differences between males and females are not surprisingly those directly relevant to reproduction. The neural underpinnings controlling sex behavior and control of gonadal function are establishing during a developmental sensitive period by the differential hormonal milieu found in males versus females. Considerable advances have been made in identifying the cellular mechanisms of early organizational effects of testosterone and its metabolite estradiol, which then determine adult physiology and behavior. These mechanisms are highly brain region specific and impact on cell death, axonal projections and synaptogenesis, resulting in a brain that combines varying degrees of maleness and femaleness. The study of reproductive endpoints is valid in its own right but also provides insight into the more subtle sex differences associated with cognition, emotionality, social behavior and relative risk of neurological disorders and diseases of mental health. 0:26 Sex differences in brain and behavior are determined by: 0:38 In humans, environment and experience are probably dominant 1:00 To understand the cultural ... 1:12 To understand the cultural 1:57 Laboratory Rat 2:08 Sex differences in brain and ... 2:25 Type One: Sex Dimorphism 3:00 Type Two: Sex Difference 3:22 Type Three: Sex Convergence 4:00 Sex differences in the brain (1) 4:56 Sex differences in the brain (2) 5:51 Sex differences in brain and behavior are determined by: Hormones 6:19 Genetic sex determines gonadal sex which determines phenotypic sex 7:40 Brain sexual differentiation occurs early 9:38 How do we connect brain sex differences to sex differences in behavior? 10:35 Type One: Sex Dimorphism 10:54 Thesis research of Stuart Amateau and Christopher Wright 11:45 Steroids change the number of synapses 12:21 Is there a sex difference in dendritic spines in the newborn brain?