lecture 12 Flashcards
what is Insomnia
Insomnia is characterized as difficulty falling asleep after going to bed or after awakening during the night
Insomnia is a problem that affects how many people
approximately 25 percent of population occasionally and 9 percent regularly
what is Fatal Familial Insomnia & Sporadic Fatal Insomnia
A very rare disease that involves progressively worsening insomnia, which leads to hallucinations, delirium, and confusional states. It is typically inherited but can also develop spontaneously. It has no known cure and the average survival span after the onset of symptoms is 18 months.
are there DISORDERS ASSOCIATED WITH NON-REM SLEEP (NREM PARASOMNIAS)
yes
There are many sleep disorders that occur during NREM sleep or during transitions out of sleep… what happens to the brain
The brain seems to get caught in between a sleeping and waking state. Many people are unaware they exhibit this behaviour.
what are some NREM PARASOMNIAS
Sleepwalking, Sleep-talking, Sleep-groaning, Sleep-crying, Sleep-eating, Sleep-sex, Sleep-teeth grinding
what are characteristics of Sleepwalking, Sleep-talking, Sleep-groaning, Sleep-crying, Sleep-eating, Sleep-sex, Sleep-teeth grinding
Some of these conditions tend to be more prevalent in children (i.e., people can grow out of it). Episodes can last seconds to minutes or longer. These states can be caused by certain medications or medical conditions.
what are Sleep terrors
NREM
Characterized by overwhelming feelings of terror upon waking (from stage 3/4 sleep). May include panic (a panic attack), screaming, and even bodily harm because of rash actions. People sometimes have no recollection of these events. Prevalent in people diagnosed with post-traumatic stress disorder (PTSD
what is REM sleep behavior disorder
Neurological disorder in which the person does not become paralyzed during REM sleep and thus acts out dreams
• Appears to be a neurodegenerative disorder with at least some genetic component
• It is often associated with better-known neurodegenerative disorders such as Parkinson’s disease
give an overview of REPRODUCTIVE BEHAVIOR
Reproductive behaviors constitute most important category of social behaviors, because without them, most species would not survive
•These behaviors include courting, mating, parental behavior, and most forms of aggressive behaviors
•These behaviors are the most striking categories of sexually dimorphic behaviors
what is Sexual dimorphic behavior
behavior that has different forms (or that occurs with different probabilities or under different circumstances) in males and females
In terms of behaviour, there are differences between the sexes, on average, in their mixture of talents, temperaments, and interests. These differences can be the result of what
biology, socialization, and the interaction of the two.
does biology hard-wires some differences
yes
Men and women have specific, hard-wired differences in both their bodies and brains. Exposure to sex hormones, both before and after birth, is responsible for this sexual dimorphism.
what are sex chromosomes
The X and Y chromosomes are the sex chromosomes, as they typically determine an organism’s sexual identity
what are gametes
Mature reproductive cells
Mature reproductive cells (gametes) only have how many copies of chromosones
one copy of every chromosome
Mature reproductive cells (gametes) only have one copy of every chromosome. These reproductive cells, are made where
made in the gonads
what are gonads
ovaries or testes
Mature reproductive cells (gametes) only have one copy of every chromosome. These reproductive cells, made in the gonads are what
either sperm or ova
All embryos contain precursors for both female and male sex organs, but during third month of gestation what happens
one of these precursors typically develops while the other withers away.
All embryos contain precursors for both female and male sex organs, but during third month of gestation one of these precursors typically develops while the other withers away
what are these 2 precursers
Müllerian system
Wolffian system
what is the Wolffian system
Embryonic precursors of male internal sex organs
what is the Müllerian system
Embryonic precursors of female internal sex organs
In humans, biological sex is determined by five factors present at birth what are they
Sex chromosomes: XX or XY • Gonads: testes or ovaries • Sex hormones: androgen signaling • Internal reproductive anatomy • External anatomy
what are the Sex chromosomes
XX or XY
what are the gonads
testes or ovaries
what is Sex hormones
androgen signaling
In humans, biological sex is determined by five factors present at birth
Generally, the five factors are either all male or all female. Unexpected combinations cause what
intersex conditions, in which the person cannot be distinctly identified as male or female.
what is Transgender
when people identify with a gender that is different than the gender they were classified as at birth
what are The three categories of sex organs
Gonads: testes or ovaries
Internal reproductive anatomy
• External anatomy
explain FEMALE SEX ORGAN DEVELOPMENT
XX chromosome –> Development of ovaries–>
largely silent until puberty
Puberty is triggered by what
hormones released from gonads (ovaries or testes)
If the ovaries don’t do anything until puberty, what triggers development of female sex organs?
External female sex organs (the vulva) develop in the absence of androgen hormones.
• Internal female sex organs develop in the absence of anti-Müllerian hormone. This includes the (inner) vagina, uterus, and fallopian tubes
If you do not have two X chromosomes what happens
you will not have ovaries
External female sex organs (the vulva) develop how
in the absence of androgen hormones.
Internal female sex organs develop how
in the absence of anti-Müllerian hormone. This includes the (inner) vagina, uterus, and fallopian tubes.
what is the SRY gene
One specific gene on the Y chromosome known as the SRY gene encodes a protein that causes the undifferentiated fetal gonads to develop into testes
is the SRY gene dominant
This gene overpowers XX-ovary instructions, so XXY individuals develop testes
explain MALE SEX ORGAN DEVELOPMENT
SRY gene –> development of testes–> embryonic testicular release of: 1) anti-Müllerian hormone or 2) androgens (testosterone)
if 1–> Stops development of Mullerian system (internal female sex organs)
if 2–> Triggers development of male sex organs (both internal and external)
with regard to MALE SEX ORGAN DEVELOPMENT what is the defeminizing effect
Effect of anti-Müllerian hormone early in development, which prevents development of the internal anatomy typical of females
with regard to MALE SEX ORGAN DEVELOPMENT what is the Masculinizing effect
Effect of androgen hormones early in development, which promotes anatomical and behavioral characteristics typical of males
with regard to MALE SEX ORGAN DEVELOPMENT what are Androgens
Male sex steroid hormones
Testosterone is the principal mammalian androgen.
Dihydrotestosterone is also one that it is made from testosterone. It triggers development of male external sex organs.
for genetic abnormalities:
To gain an appreciation for the complexity and delicacy of signaling cascades, let’s examine the processes that underlie sex organ development.
The first step is the development of the gonads (ovaries or testes), which requires specific DNA: which are
either two X chromosomes or the SRY gene
what is Turner Syndrome
is when you only have one sex chromosome (X0).
what is Swyer Syndrome
when you are XY, but have a bad SRY gene
In both cases (of turner and sawyer syndrome) what happens
gonads do not develop, nether testes nor ovaries. Internal and external female sex organs will develop normally, since there are no testicular hormones, but the person will be sterile since they also lack ovaries. Without gonads, puberty will have to be artificially induced (with the hormone estradiol). (Turner Syndrome is associated with other developmental abnormalities on account of missing a full chromosome.)
are there people who have two or more X chromosomes and the SRY gene (e.g., XXY or XXXY).
yes
There are also people who have two or more X chromosomes and the SRY gene (e.g., XXY or XXXY) what happens
They typically develop as men with small testes, who are often sterile and have trouble growing a beard
with regard to genetics abnormalities, Lets now assume that the person has XY (male) chromosomes and their SRY gene successfully triggered development of testes. We know the testicular hormones include the anti-Müllerian and androgen hormones.
What if the production of one of these hormones is insufficient or the receptors for one of them is lacking in either number or function?
Insufficient anti-Müllerian hormone
or
Insufficient androgen hormone
what is Insufficient anti-Müllerian hormone signaling
Insufficient anti-Müllerian hormone signaling will cause insufficient defeminiziation: both male and female internal sex organs will develop and get tangled together. There is often functional external male genitalia.
what is Insufficient androgen hormone signaling
Insufficient androgen hormone signaling will cause insufficient masculinization. In severe cases, no internal sex organs develop, yet the person will have external female genitalia and typically identify as a heterosexual woman, but will be sterile and have a short vagina
what is androgen insensitivity syndrome
Insufficient androgen hormone signaling will cause insufficient masculinization. In severe cases, no internal sex organs develop, yet the person will have external female genitalia and typically identify as a heterosexual woman, but will be sterile and have a short vagina.
This situation is known as androgen insensitivity syndrome, and is often graded from 1 to 7 based on the degree of genital masculinization:
androgen insensitivity syndrome, is often graded from 1 to 7 based on the degree of genital masculinization: explain them
Grade 1 is the mild form: the external genitalia is fully masculinized
o Grade 6 or 7 is the severe form: the external genitalia is fully feminized o Grades 2 - 5 are given when the genitalia are in between, mixed.
what is Behavioral defeminization
Refers to organizational effect of androgens on the brain that prevent animals from displaying female-typical behaviors in adulthood
what is Behavioral masculinization
Refers to organizational effect of androgens on the brain that enables animals to engage in male-typical behaviors in adulthood
is The human brain sexually dimorphic
The human brain is a sexually dimorphic organ. The sizes and interconnectivity of different brain regions vary according to biological sex and sexual identity.
Some of the differences between male and female brains are clearly caused by what
genetic and hormonal differences during development.
do boys and girls prefer different toys
Children typically show sex differences in behaviors such as toy preferences.
Boys generally prefer toys that can be used actively, especially those that move or can be propelled by the child. Girls generally prefer toys that provide the opportunity for nurturance.
Of course caregivers and peers encourage sex-typical toy choices, but even at one day of age baby boys prefer to watch a moving mobile and baby girls prefer to look at a female face.
Young vervet monkeys show the same sexually dimorphic preferences in choice of toys that children do: Males chose to play with a car, whereas females preferred to play with a doll.
what are Organizational Effects
Sex hormones influence the development of the body and brain. These effects are permanent and put you on a particular trajectory going forward.
what are Activational Effects
After development, sex hormones influence the body and mind. The production of sperm, ovulation, erections and ejaculations, and general horniness are all examples of activational effects. The same hormones can cause different activational effects in males and females.
The organizational effects of hormones on the body (on sex organs) is largely over when
by birth
The organizational effects of hormones on the body (on sex organs) is largely over by birth. However, the organizational effects of hormones on the brain continues for how long in rodents
a few weeks after birth, at least in rodents.
is it possible to induce hormonal control of sexual behaviour in rodents
The organizational effects of hormones on the body (on sex organs) is largely over by birth. However, the organizational effects of hormones on the brain continues for a few weeks after birth, at least in rodents.
• One consequence of this is that we can masculinize or feminize the brain of rodents by altering hormone signaling immediately after birth, after the development of their sex organs is complete.
• For example, when male rodents are castrated at birth (which stops further androgen signaling), they develop some female-typical behaviours. If they are injected with female hormones in adulthood (estradiol and progesterone), they will try to get other males to have sex with them (they will assume lordosis in the presence of other males).
• Similar injections in non-castrated male rats have relatively small behavioural consequences, at least following single injections
In many mammalian species, the role of females in sex seems to be what
at first glance, appears to just be to assume a position. (This behavior is called the lordosis response from Greek lordos, meaning bent backward.)
will female rodents initiate copulation (sex)
females often actively initiate copulation; they can entice males by sniffing and nuzzling the males’ genitals. They also hop around and wiggle their ears. These behaviours depend on ovarian hormones - estradiol and progesterone.
• Ovarian hormones in (estrous) females influence their willingness (and eagerness) to mate. They also influence their ability to mate, as males typically cannot copulate successfully with a female that is not in estrous.
Male rats are most responsive to a female rat when
Male rats are most responsive to a female rat in ‘heat’. Males will ignore females whose ovaries have been removed but injections of estradiol and progesterone will increase her attractiveness
Both menstrual and estrous cycles are controlled by what
the ovarian hormones estradiol and progesterone
what is Menstrual cycle and does it impact sexual activity
Female reproductive cycle of most primates, including humans
• Characterized by menstruation (if pregnancy does not occur)
• Sexual arousal is somewhat influenced by ovarian hormones, but ability to mate is not. Animals with a menstrual cycle exhibit sexual activity throughout the cycle.
what is the Estrous cycle
Female reproductive cycle of mammals other than most primates
• Females that have estrous cycles do not menstruate; they reabsorb their endometrium. Also, they are typically only sexual active during the estrous phase of their cycle, which ranges across species from once a year to once every few days.
• This is often referred to as being “in heat”. This change in behavior alters the behavior of nearby males.
for HUMANS does fertility impact sexual activity
Women do not seem to become indiscriminately more interested in sexual contact during their fertile period. Instead, they often seem to become more choosy
Sequence of estradiol followed by progesterone has three effects on female rats what are they
Proceptivity
Receptivity
Attractiveness
explain Proceptivity
a female’s eagerness to copulate, as shown by the fact that she seeks out a male and engages in behaviors that tend to arouse his sexual interest.
explain Receptivity
ability and willingness to copulate—to accept the advances of a male by holding still and displaying lordosis.
explain Attractiveness:
physiological and behavioral qualities that attract the male. Proceptive behaviours are one means of increasing attractiveness. Pheromones (odors) are another.
The adrenal glands of humans, which both males and females have, typically secrete small amount of androgens. However, some people have adrenal glands that secrete abnormally large amounts of androgens, both before and after birth
what happens when this is the case for males
In males, this excess androgen signaling from their adrenal glands has minimal effect, since their testes are already secreting tons of androgens. This condition is known as congenital adrenal hyperplasia (CAH).
The adrenal glands of humans, which both males and females have, typically secrete small amount of androgens. However, some people have adrenal glands that secrete abnormally large amounts of androgens, both before and after birth
what happens when this is the case for FEMALES
However, in females, excess androgen signaling can cause some degree of masculinization, of either the body or brain or both.
This condition is known as congenital adrenal hyperplasia (CAH).
Depending on the amount of androgen signaling during development, sex organs can become slightly masculinized (e.g., enlarged clitoris, partially fused labia). Brain anatomy/function can be masculinized as well. Women with CAH have a higher likelihood of identifying as a man and being sexual attracted to other women.
what is The implication of the research on hormonal control of sexual behaviour
The implication of this research is that homosexuality and transgenderism may be caused by variations in the timing or effectiveness of androgen signaling during development in specific brain regions. This would presumably result in altered brain structure or function.
WHAT TRIGGERS SEXUAL MATURATION (PUBERTY)
Kisspeptin
Gonadotropin- releasing hormone
Gonadotropic hormones
what is Kisspeptin
Neuropeptide produced by neurons in the arcuate nucleus of the hypothalamus that initiates puberty and maintains reproductive ability by triggering release of gonadotropin-releasing hormone
what is Gonadotropin- releasing hormone
Hypothalamic hormone that stimulates anterior pituitary gland to secrete gonadotropic hormone
what is Gonadotropic hormones
Hormones of pituitary gland (follicle-stimulating hormone, FSH, and luteinizing hormone, LH) that have stimulating effect on cells of gonads
what is Estrogen
Class of sex hormones typically released by the ovaries that cause maturation of the physical features characteristic of females, such as and growth of breast tissue and female genitalia
what is Estradiol
Principal estrogen of many mammals, including humans
what are the ACTIVATIONAL EFFECTS OF SEX HORMONES IN MEN
Men resemble other mammals in their behavioral responsiveness to testosterone.
• With normal levels of testosterone, men can be fertile; without testosterone sperm production ceases, and sooner or later, so does the ability to have sex.
• A castrated male rat will cease sexual activity, but it can be reinstated with a injection of testosterone.
• Men taking a gonadotropin-releasing hormone antagonist will not show testicular release of androgens and have a decrease in sexual interest and intercourse
what is the Refractory period
Period of time after particular action (for example, an ejaculation by a male) during which that action cannot occur again
what is the Coolidge effect
Restorative effect of introducing a new sex partner (or new erotic stimuli) after the animal had already become “exhausted” by sexual activity. This effect is not just a male phenomenon. Similar phenomena are seen in all types of reward seeking behaviour (such as being full from dinner but when dessert is announced you can suddenly find room to eat more)
By injecting transneuronal retrograde tracer in muscles responsible for lordosis response in female rats, researchers identified the important neural pathways: what are they
VMH –> PAG –> nPGi –> motor neurons in spinal cord
what is Ventromedial nucleus of hypothalamus (VMH)
Large nucleus in the hypothalamus that plays essential role in female sexual behavior
Ventromedial nucleus of hypothalamus (VMH)
Large nucleus in the hypothalamus that plays essential role in female sexual behavior. In rodents…
Electrical stimulation of VMH facilitates female sexual behavior.
• Injections of estradiol and progesterone directly into VMH also stimulates sexual behavior, even in females whose ovaries have been removed.
• Female with bilateral lesions of VMH will not display lordosis, even if she is treated with estradiol and progesterone
The important neural pathways for male sexual behavior include:
mPOA –> PAG –> nPGi –> motor neurons in spinal cord
what is Medial Preoptic Area (mPOA)
Nucleus in the anterior hypothalamus that plays essential role in male sexual behavior.
explain the characteristics Medial Preoptic Area (mPOA)
Electrical stimulation of mPOA in rodents elicits male copulatory behavior.
• Within the mPOA, there is an area called the sexually dimorphic nucleus (SDN)
of preoptic area. This nucleus is much larger in males than in females.
• Lesioning the mPOA of female rats does not affect their sexual behavior. It does make them bad mothers, however. It causes them to ignore their offspring
There are inhibitory serotonergic projections from the nPGI to neurons in the spinal cord that control ejaculation what are they
Application of serotonin (5-HT) to spinal cord suppresses ejaculation
– Men who take SSRIs as treatment for depression often have difficulty achieving ejaculation, even though they do not typically have trouble getting an erection
Formation of long lasting, monogamous-ish pair bonds happens to what animals
In approximately 5 percent of mammalian species, sexually mature couples tend to form long-lasting, fairly monogamous pair bonds
The formation of pair bonds seems to relate to two peptides in brain: what are they
vasopressin and oxytocin
what is special about vasopressin and oxytocin
These compounds are released as neurotransmitters in the brain as well as hormones in the blood.) These peptides are released during sex, childbirth, and breastfeeding
Some species of prairie voles form pair bonds and some don’t. The species that do form pair bonds have more what
oxytocin receptors in their ventral forebrain than the other species do
Some species of prairie voles form pair bonds and some don’t. The species that do form pair bonds have more oxytocin receptors in their ventral forebrain than the other species do. Pharmacologically blocking or activating these oxytocin receptors influences what
who they choose to pair up with and when
Some species of prairie voles form pair bonds and some don’t. The species that do form pair bonds have more oxytocin receptors in their ventral forebrain than the other species do. Pharmacologically blocking or activating these oxytocin receptors influences who they choose to pair up with and when. And, artificially increasing oxytocin receptor expression in species of non-monogamous prairie voles can do what
cause them to form life long, monogamous-ish pair bonds
do Love and addiction affect intelligence
Love and addiction do not affect overall intelligence; they skew priorities and choice behaviour
explain Falling in love (or becoming a drug addict)
To ensure that we attain critical biological goals (e.g., survival, reproduction), specific brain circuits determine how valuable things are to us.
• Unlike memorizing your numbers and letters, deep emotional learning completely alters what matters to you. Love and addiction do not affect overall intelligence; they skew priorities and choice behaviour.
• “I felt as though I couldn’t survive without it.” If you believe that something silly is essential to your survival, your priorities won’t make sense to others. People with an addiction can push through negative experiences because they feel as though they can’t survive without that thing, substance, or person.
• Getting over a devastating breakup is somewhat like recovering from addiction. Healing a broken heart is difficult and often involves relapses into obsessive behavior.
• The brain areas that mediate these decisions and set priorities regulate our motivational processes and feelings of pleasure and happiness.
