Psyc4130 1nd Edition Lecture 19 Outline of Last Lecture I Turners Syndrome II Congenital Adrenal Hyperplasia III Secondary Sexual Development IV Hormone Control of Menses V Progesterone VI Testosterone Fuels Libido a Males b Females VII Refractory Period a Coolidge Effect VIII Hormones IX Pheromones X XI XII Allomones The Vomoeronasal Organ Pheromonal Phenom in Rodents Outline of Current Lecture I Pheromonal Phenom in Rodents II Pheromones in Humans a McClintock Effect These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute III Human Sexual Attraction Pheromones a Androstadienone b Estratetraene IV Dimorphisms a Aromarase b oSDN c Sexual orientation and SDN V What Causes Homosexuality Current Lecture Pheromonal Phenom in Rodents Vandenbergh effect in the presence of a male puberty is accelerated Bruce Effect spontaneous abortion elicited when a recently impregnated female mouse encounter a male other than the one that impregnated her Pheromones in Humans VNO present but vestigial However the main olfactory system i e epithelium in humans still appears to register the effects of certain pheromones Are not consciously aware of the smell of pheromones but effects the neurophysiology of the cells not experiential These differentially influencer sex related behaviors in heterosexual men and women Kissing pheromonal compatibility Urine high concentration of pheromones in urine McClintock Effect synchronized cycles in cohabitating women o A pheromone present in underarm sweat appears to be key Russell et al 1980 o It does regulate women s cycles Lower ranking socially female will adjust their cycles to socially dominant female Extracts from the sweat of men advanced the onset of the next surge in LH reduced anxiety and increased relaxation in women Preti et al 2003 o Speeds up ovulation o Adaptive only time they might get prego Human Sexual Attraction Pheromones Androstadienone o AND is an adrogenic chemical shown to enhance positive affect and sexual arousal in women but to decrease positive affect in men feel better lift mood AND then Estratetraene o EST is an estrogenic chemical which in men but not in women activates hypothalamic nuclei associated with sexual responding Go EST young man Dimorphisms To what extent are male and females brains different today don t see structural differences in brains Goats 8 10 are gay aka ewes sexual behavior o Some species of animals have been seen to have homosexual sexual behavior Aromarase o Turns testosterone into estrogen defeminizes the males brain oSDN o Sexually dimorphic nucleus o Preoptic area o Nucleus that looks structurally different in male vs female sheep Sexual Orientation and the SDN o Figure 10 12 sexual dimorphism and role of sexual orientation in the volume and number of neurons in the SDN in sheep Hypothetically gender identification o Bed nucleus of the stria terminalis BNST o BNST carries signals form centromedial amygdala to ventrical medial nucleus VMN of the hypothalamus o 10 13 the human BNST o The unicate nucleus of hypothalamus is 2x in men compared to women and in females What Causes Homosexuality Domineering mother hypothesis roundly discredited as an explanation of male homosexuality Maternal stress however might play a role in decreasing the effectiveness of prenatal androgens Wards 1972 o i e they are less capable of defeminizing the male brain o Nothing absolutely causes it See correlations influenced and factors that tend to make it more likely but not CAUSES a person to be born gay Circulating levels of androgens in adult males is not a factor whatsoever Genetic contribution appears significant o 52 concordance rate for MZ twins Vs 22 for DZ twins o Some estimates as high as 60 for MZ twins
View Full Document
Unlocking...