Save
Winter 2024
PSYB64
final
Save
Share
Learn
Content
Leaderboard
Learn
Created by
jess kerzner
Visit profile
Cards (235)
Zeitgebers
: stimuli that help
establish
and
maintain
biorhythms
the
sun
is the most important
zeitgeber
larks
=
morning
people
night owls
= most
adolescents
larks
(stability) have
low
neuroticism,
high
agreeableness, and
high
conscientiousness
night owls
(plasticity) have more
openness
and
extraversion
the same differences in
serotonergic functioning
that are hypothesized to contribute to
personality stability
may be responsible for
morningness
teens reflect changes in melatonin release (pineal gland)
after teen years, people tend to stop being night owls
might indicate brain maturity
night shifts
interfere with circadian rhythm
5-10
% of night workers
jet lag
is worse when traveling
east
daylight savings
phase advance
in
fall 1 hour
(
west
)
phase delay
in
spring 1 hour
(
east
)
daylight savings
time correlates with more
heart attacks
since
sleep deprivation
leads to
inflammation
and
sympathetic activation
the body's
master clock
is the
suprachiasmatic nucleus
(SCN)
the SCN has
per
,
tim
, and
clock
proteins
the SCN is above the
optic chiasm
(
supra
)
SCN
receives information from special cells in the retina called
intrinsically photosensitive retinal ganglion cells
(ipRGC)
ipRGC
no visual image processing
contains
photopigment
called
melanopsin
contributes to
pupil light reflex
the
photopigment melanopsin
chemically changes in response to
light
SCN
is only
active
during the
day
and helps distinguish between day and
night
SCN
-->
SNS
-->
pineal gland
melatonin
does not keep you
asleep
, it only helps
initiate
it
low
SCN activity -->
low
sympathetic activity -->
pineal
activity rises, more
melatonin
SCN can generate and maintain rhythms
independently
isolated
SCN tissue shows cycle
SCN
transplantation
shows original cycle
peripheral clocks
exist but
SCN
is
quicker
SCN adjusted after
1-2
cycles, lungs
6
cycles, and liver
16
cycles in rats
peripheral clocks
are more strongly influenced by
daily feeding cycles
SCN
receives
light
from
retina
but still maintains own
timekeeping
mechanisms
per (
period
) gene, tim (
time
) gene,
clock
gene produce
proteins
if
high
tim and per,
low
clock
if
low
tim and per,
high
clock
clock protein
-
circadian locomotor output
cycles kaput
the
24 hour
production and
degradation
of specific
proteins
enables
SCN
to tell time
clock
increases
tim
and
per
pineal gland
dependent on
SCN
for
circadian rhythms
melatonin
diffuses into
CSF
of
3rd
ventricle
melatonin
suppressed by
light
, peaks at
4am
taking too much
melatonin
can lead to
sleepiness
during the day
pineal gland
can disrupt
hormones
(
testosterone
and
estrogen
) and can interact with other
medications
,
thinning
blood
cortisol
released by
adrenal
gland, promotes
arousal
cortisol
is highest in the
early morning
and remains in the blood for
3
hours
See all 235 cards