Sex and the Brain Flashcards
describe the classification of sex differences (sexual dimorphism, sex differences, sex convergence)
- sexual dimorphism: endpoint consists of 2 forms (one form in males, another in females)
- copulatory behavior, bird song
- sex differences: endpoint exists on a continuum and average is different between males and females
- pain threshold, fear, anxiety, learning, memory
- sex convergence: endpoint is the same but neural underpinnings are different
- parental behavior, problem-solving strategies
describe sex ratios in CNS disorders
higher freq. of developmental onset disorders in males and adult onset disorders in females
- male-biased conditions
- ADHD 10:1
- autism spectrum disorder 4:1
- dyslexia 3:5:1
- Tourette syndrome 3:1
- female-biased conditions
- anorexia 13:1
- autoimmune disorders 3:1
- depression 2:1
- anxiety disorder 2:1
the _____ is 4x larger in male rats than in female rats
the sexually dimorphic nucleus (SDN) is 4x larger in male rats than in female rats
describe the differences seen in human suprachiasmatic nuclei (SCN) of the hypothalamus
describe the relationship between INAH-3 and sexual orientation and gender identity
- INAH-3 is larger in males than in females
- INAH-3 and sexual orientation
- maker for sexual orientation
- smaller in homosexual than heterosexual men
- same size in women and in homosexual men
- INAH-3, BNST is smaller in transgender persons (M to F) than in males and similar in size as in females
the bed nucleus stria terminalis (BNST) is (greater/lesser)? in males than in females
the bed nucleus stria terminalis (BNST) is greater in males than in females
name the 5 regions of the female brain that has higher gray matter density than males
- left and right caudate
- left and right hippocampus
- left inf. frontal
- right orbitofrontal
- left and right gyrus rectus
describe advantages in tasks between male and females
- visual rotation advantage in males
- language, reading, verbal fluency advantage in females
which gene is the sex determining gene and where is it located?
the SRY gene on the Y chromosome is the sex determining gene
describe the critical periods in sexual differentiation
describe the molecular mechanism of testosterone action
- testosterone does not act directly ont he cells of the developing nervous system; it gets converted into estradiol via aromatase, which then acts on cells
describe AIS (androgen insensitivity syndrome)
- AIS is caused by a mutation in the gene that produces androgen receptors and leads to a female phenotype
describe diethylstilbestrol (DES) daughters
- normal: SDN larger in males than in females
- experiment: SDN larger in DES treated females than in female controls (DES also blunted LH secretion)
- conclusion: DES exposure during the critical period of sexual differentiation of the brain causes masculinization of the brain
