PSYC550 Sleep and Sex

Download Report

Transcript PSYC550 Sleep and Sex

PSYC550
Biological Bases of Behavior
Sleep and Sex
A Physiological and
Behavioral Description of
Sleep
• alpha activity
– Smooth electrical activity of 8-12 Hz recorded from the brain;
generally associated with a state of relaxation.
• beta activity
– Irregular electrical activity of 13-30 Hz recorded from the brain;
generally associated with a state of arousal.
• theta activity
– EEG activity of 3.5-7.5 Hz that occurs intermittently during early
stages of slow-wave sleep and REM sleep.
• delta activity
– Regular synchronous electrical activity of less than 4 Hz recorded
from the brain; occurs during the deepest stages of slow-wave
sleep.
SWS vs REM
• NREM (SWS in stages 3 and 4)
–
–
–
–
–
Alpha, delta, and theta activity
Light, even respiration
Lowered BP
Muscle control is present
Difficult to arouse (especially from stage 4)
• REM
–
–
–
–
–
–
–
Asynchronized beta
Increased respiration and BP
REM
PGO waves
Spinal paralysis
Dreams
Sexual arousal
A Physiological and
Behavioral Description of
Sleep
• REM sleep
– A period of desynchronized EEG activity during sleep, at which
time dreaming, rapid eye movements, and muscular paralysis
occur; also called paradoxical sleep.
• non-REM sleep
– All stages of sleep except REM sleep.
• slow-wave sleep
– Non-REM sleep, characterized by synchronized EEG activity
during its deeper stages.
• basic rest-activity cycle
– A 90-minute cycle (in humans) of waxing and waning alertness,
controlled by a biological clock in the caudal brain stem; controls
cycles in REM sleep and slow-wave sleep.
Neurotransmitters involved
in Sleep
• Serotonin
– In raphe and pons
– Increased in SWS, decreased in REM
• Dopamine
– Decreased in REM
• Norepinephrine
– Decreased in REM
• Acetylcholine
– Greatly increased in REM
I get 8 hours of sleep each
night, without fail.
Strongly Agree
Agree
Disagree
Strongly Disagree
ag
re
e
gr
ee
Di
s
is
a
ly
St
ro
ng
A
gr
ee
D
ly
Ag
re
e
25% 25% 25% 25%
St
ro
ng
1.
2.
3.
4.
Disorders of Sleep
• insomnia
– Discuss sleep hygiene
• drug dependency insomnia
– An insomnia caused by the side effects of ever-increasing doses of sleeping
medications.
• sleep apnea
– Cessation of breathing while sleeping.
• narcolepsy
– A sleep disorder characterized by periods of irresistible sleep, attacks of
cataplexy, sleep paralysis, and hypnagogic hallucinations.
• sleep attack
– A symptom of narcolepsy; an irresistible urge to sleep during the day, after
which the person awakens feeling refreshed.
St
ro
ng
ly
D
Di
s
is
a
ag
re
e
gr
ee
gr
ee
A
Ag
re
e
ly
St
ro
ng
1.
2.
3.
4.
People with narcolepsy collapse
into sleep from total alertness
without warning.
Strongly Agree
25% 25% 25% 25%
Agree
Disagree
Strongly Disagree
10
http://www.youtube.com/watch?v=tOAvWbspeSQ&feature=related
Narcolepsy
• cataplexy
– A symptom of narcolepsy; complete paralysis that occurs during
waking.
• sleep paralysis
– A symptom of narcolepsy; paralysis occurring just before a
person falls asleep.
• hypnagogic hallucination
– A symptom of narcolepsy; vivid dreams that occur just before a
person falls asleep; accompanied by sleep paralysis.
• hypocretin
– A peptide, also known as orexin, produced by neurons whose cell
bodies are located in the hypothalamus; their destruction causes
narcolepsy.
Disorders of Sleep
• REM sleep behavior disorder
– A neurological disorder in which the person does not
become paralyzed during REM sleep and thus acts out
dreams.
•
•
•
•
•
Night terrors vs nightmares
Somnambulism
Somniloquy
Enuresis
Bruxism
Why do we sleep?
1. For restoration
2. To consolidate
memory
3. To remain safe from
predators
4. To learn to relax
re
la
x
...
ar
n
to
fro
m
le
To
m
ai
n
re
To
To
co
ns
Fo
ol
id
sa
fe
at
e
rr
es
to
ra
tio
n
m
em
or
y
25% 25% 25% 25%
10
Why Do We Sleep?
• sleep-related eating disorder
– A disorder in which the person leaves his or her bed and seeks
out and eats food while sleepwalking, usually without a memory
for the episode the next day.
• fatal familial insomnia
– A fatal inherited disorder characterized by progressive insomnia.
• rebound phenomenon
– The increased frequency or intensity of a phenomenon after it
has been temporarily suppressed; for example, the increase in
REM sleep seen after a period of REM sleep deprivation.
• adaptive response to danger
Physiological Mechanisms
of Sleep and Waking
• locus coeruleus
– A dark-colored group of noradrenergic cell bodies located in the pons near
the rostral end of the floor of the fourth ventricle; involved in arousal and
vigilance.
• raphe nucleus
– A group of nuclei located in the reticular formation of the medulla, pons, and
midbrain, situated along the midline, contains serotonergic neurons.
• tuberomammillary nucleus (TMN)
– A nucleus in the ventral posterior hypothalamus, just rostral to the mammillary
bodies; contains histaminergic neurons involved in cortical activation and
behavioral arousal.
• ventrolateral proptic area (VLPA)
– A group of GABAergic neurons in the preoptic area whose activity suppresses
alertness and behavioral arousal and promotes sleep.
Physiological Mechanisms
of Sleep and Waking
• PGO wave
– Bursts of phasic electrical activity in the pons, followed
by activity in the lateral geniculate nucleus and visual
cortex, a characteristic of REM sleep.
• medial pontine reticular formation (MPRF)
– A region that contains neurons involved in the initiation
of REM sleep; activated by acetylcholinergic neurons of
the peribrachial area.
Physiological
Mechanisms of Sleep and
Waking
• magnocellular nucleus
– A nucleus in the medulla; involved in the muscular
paralysis that accompanies REM sleep.
Biological Clocks
• circadian rhythm
– A daily rhythmical change in behavior or physiological process.
• zeitgebers
– A stimulus (usually the light of dawn) that resets the biological
clock that is responsible for circadian rhythms.
• suprachiasmatic nucleus (SCN)
– A nucleus situated atop the optic chiasm. It contains a biological
clock that is responsible for organizing many of the body’s
circadian rhythms.
• melanopsin
– A photopigment present in ganglion cells in the retina whose
axons transmit information to the SCN, the thalamus, and the
olivary pretectal nucleus.
Biological Clocks
• pineal gland
– A gland attached to the dorsal tectum; produces
melatonin and plats a role in circadian and seasonal
rhythms.
• melatonin
– A hormone secreted during the night by the pineal
body; plays a role in circadian and seasonal rhythms.
Sexual Development
• sry
– The gene on the Y chromosome that instructs the
undifferentiated fetal gonads to become testes.
• organizational effect (of hormone)
– The permanent effect of a hormone on tissue differentiation and
development.
• activational effect (of hormone)
– The effect of a hormone that occurs in the fully developed
organism; may depend on the organism’s prior exposure to the
organizational effects of hormones.
Sexual Development
• defeminizing effect
– An effect of a hormone present early in development that reduces or prevents
the later development of anatomical or behavioral characteristics typical of
females.
• androgen
– A male sex steroid hormone; stimulates the development of the Wolffian
system. Testosterone is the principal mammalian androgen.
• masculinizing effect
– An effect of a hormone present early in development that promotes the later
development of anatomical or behavioral characteristics of males.
• testosterone
– The principal androgen found in males.
AIS
• androgen insensitivity
syndrome
– A condition caused by a
congenital lack of
functioning androgen
receptors; in a person with
XY sex chromosomes,
causes the development of a
female with testes but no
internal sex organs.
Sexual Development
• Turner’s syndrome
– The presence of only one sex chromosome (an X
chromosome); characterized by lack of ovaries but
otherwise normal female sex organs and genitalia.
Sexual Development
• follicule-stimulating hormone (FSH)
– The hormone of the anterior pituitary gland that causes development of an
ovarian follicle and the maturation of an ovum.
• luteinizing hormone (LH)
– A hormone of the anterior pituitary gland that causes ovulation and
development of the ovarian into a corpus luteum.
• estradiol
– The principal estrogen of many mammals, including humans.
• estrogen
– A class of sex hormones that cause maturation of the female genitalia, growth
of breast tissue, and development of other physical features characteristic of
females.
Copyright © Allyn & Bacon 2007
Hormonal Control of
Sexual Behavior
• oxytocin: The big “O”
– A hormone secreted by the posterior pituitary gland; causes
contraction of the smooth muscle of the milk ducts, the uterus,
and the male ejaculatory system; also serves as a neurotransmitter
in the brain.
• prolactin
– A hormone of the anterior pituitary gland, necessary for
production of milk; has an inhibitory effect on male sexual
behavior.
• lordosis
– A spinal reflex seen in many four-legged animals; arching of the
back in response to approach of a male or to touching the flanks,
which elevates the hindquarters.
Hormonal Control of
Sexual Behavior
• pheromone
– A chemical released by one animal that affects the behavior or
physiology of another animal; usually smelled or tasted.
• Lee-Boot effect
– The slowing and eventual cessation of estrous cycles in groups
of female animals that are housed together; caused by a
pheromone in the animals’ urine; first observed in mice.
• Whitten effect
– The synchronization of the menstrual or estrous cycles of a
group of females, which occurs in the presence of a pheromone
in a male’s urine.
Hormonal Control of
Sexual Behavior
• Vandenbergh effect
– The early onset of puberty seen in female animals that are housed with males;
caused by a pheromone in the male’s urine; first observed in mice.
• Bruce effect
– Termination of pregnancy caused by the odor of a pheromone in the urine of
a male other than the one that impregnated the female; first identified in mice.
• vomeronasal organ (VNO)
– A sensory organ that detects the presence of certain chemicals, especially
when a liquid is actively sniffed; mediates the effects of some pheromones.
• accessory olfactory bulb
– A neural structure located in the main olfactory bulb that receives information
from the vomeronasal organ.
Hormonal Control of
Sexual Behavior
• medial nucleus of the amygdala
– A nucleus that receives olfactory information from the
olfactory bulb and accessory olfactory bulb; involved in
the effects of odors and pheromones on reproductive
behavior.
• congenital adrenal hyperplasia (CAH)
– A condition characterized by hypersecretion of
androgens by the adrenal cortex; in females, causes
masculinization of the external genitalia.
Copyright © Allyn & Bacon 2007
Copyright © Allyn & Bacon 2007
Copyright © Allyn & Bacon 2007
Neural Control of Sexual
Behavior
• medial preoptic area (MPA)
– An area of cell bodies just rostral to the hypothalamus; plays an
essential role in male sexual behavior.
• sexually dimorphic nucleus
– A nucleus in the preoptic area that is much larger in males than in
females; first observed in rats; plays a role in male sexual
behavior.
• periaqueductal gray matter (PAG)
– The region of the midbrain that surrounds the cerebral aqueduct;
plays an essential role in various species-typical behaviors,
including female sexual behaviors.
Neural Control of Sexual
Behavior
• ventromedial nucleus of the hypothalamus (MH)
– A large nucleus of the hypothalamus located near the
wall of the third ventricle; plays an essential role in
female sexual behaviors.
The neural structure most
involved in female reproductive
behavior is:
1. Gone after the
honeymoon
2. The Medial Preoptic
Area (MPA)
3. The Ventromedial
Hypothalamus
(VMH)
4. The Hippocampus
(HPC)
Th
(..
pu
s
oc
am
ip
p
e
H
Ve
e
Th
.
...
H
nt
ro
m
ed
ia
l
pt
ic
al
ed
i
M
e
Th
G
on
e
af
te
r
th
e
Pr
eo
ho
n.
..
...
25% 25% 25% 25%
10
10
ol
in
e
in
e
ty
lc
h
A
ce
op
D
in
e
or
ep
N
am
e
ph
rin
in
ro
to
n
Se
1.
2.
3.
4.
During paradoxical sleep, you will
expect an increase in the
neurotransmitter:
Serotonin
25% 25% 25% 25%
Norepinephrine
Dopamine
Acetylcholine