Sex Flashcards
Steroid hormones
A group of hormones derived from cholesterol that act as chemical messengers in the body
male hormone (androgen)
testosterone
female hormone (estrogen)
estradiol and progestrone
Distribution of estrogen receptors
Concentrations vary between males and females
Direct effects of estrogen on neurons
Bind to various enzymes, channels and
neurotransmitter receptors to alter
membrane excitability, sensitivity to
neurotransmitters, neurotransmitter
release
Indirect effects of estrogen on neurons
Bind to estrogen receptors in the
cytoplasm and nucleus to influence
gene transcription
Activational Effects of Estrogen on Neurons
Increases number of dendritic spines on hippocampal neurons and promotes memory. Coincides with rat peak fertility and may play a role in changing reproductive needs.
Hypothalamus
Influenced by psychological and sensory information
GnRH
GnRH (gonadotropin-releasing hormone)
from the hypothalamus regulates
gonadotropin (luteinizing hormone, LH
and follicle-stimulating hormone, FSH)
release from the anterior pituitary.
Sex hormone release in males
LH stimulates androgen release
from the testes; FSH aids sperm
maturation
Sex hormone release in females
LH, FSH cause estrogen
secretion from the ovaries
Sex hormones
The sex hormones have diverse effects on
the body and also send feedback to the
pituitary and hypothalamus
Ovulation
is the process in
which a mature egg is released
from the ovary.
Pheromones:
hemicals
secreted to the outside by an
individual and received by
another individual of the same
species.
Effects of Estrogen on Sexual Behavior in females
Rise in estrogen ➛ increased sexual
interest
Effects of Estrogen on Sexual Behavior in males
Estrogen is important for
maintaining mating in males
Effects of Testosterone on Sexual Behavior in males
Anticipation of sex ➛ rise in testosterone; reduced testosterone ➛ decreased
sexual interest
Effects of Testosterone on Sexual Behavior in females
o Testosterone plays an important role in female sexual motivation
Interstitial Nuclei of the Anterior Hypothalamus (INAH)
Four INAH nuclei in the hypothalamus
* The size of INAH-3 nucleus is about twice
as large in men as in women
* Sexually dimorphic nucleus (SDN)
Bed Nucleus of the Stria Terminalis (BNST)
The extended amygdala: a center of integration for limbic
information and valence monitoring
* The number of BNST neurons in men is significantly more
compared with women regardless of male sexual orientation
Oxytocin and vasopressin release
neuropeptides/hormones
generated in the hypothalamus and released from
the posterior pituitary.
pair bonding hormones
Oxytocin (female) and vasopressin (male) increase
when forming pair-bond relationship in prairie voles.
Oxytoxcin increases
During breastfeeding in
mothers
o During sexual intercourse
in men and women.
