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Addiction? |
Sleep Deprivation ·
Antidepressant Effects,
Dopamine Antidepressant
Effects, Dopamine "So why is sleep deprivation
making a comeback now? Because use of newer antidepressant drugs together
with sleep deprivation treatment is proving effective for helping to prevent
return of depressive symptoms after sleep deprivation and for
improving depressed patients' response to their medication." WebMD: Doctors Waking Up to Benefits of Sleep
Deprivation Treatment for Depression "The hypothesis has been put forward that the antidepressant
effect of sleep deprivation (SD) is mediated by an enhanced dopamine release
resulting in an amphetamine like action of SD." "A series of studies demonstrated a possible correlation
between eye-blink rate and central dopamine activity." "Therefore, the blink rates of ·
12 drug-naive [not previously exposed to therapy or
treatment] patients with major depression and ·
12 healthy controls were compared ·
before and after SD
[sleep deprivation]
and ·
before and after 2.5
mg bromocriptine [a
medication that mimics the activity of dopamine] as a dopaminergic
[dopamine producing] challenge [a chemical substance that is administered to
a patient to see whether a normal response occurs]. The main result of the study was that ·
The depressed patients
had a significantly higher increase of blinking after SD [sleep
deprivation] both with and without a dopaminergic challenge. ·
Basal eye-blink rate was
not different in nonretarded major depression patients [individual is not
lethargic and not slow to initiate action] compared to controls. ·
Sleep deprivation
·
Bromocriptine did not
increase blink rate 1 hour after application. This result is consistent with the hypothesis that antidepressant
SD [sleep deprivation] acts through dopamine release, although it is not
conclusive, because other neurotransmitters like acetylcholine may be
involved in the regulation of blinking." "Lack of a night's sleep is paid
for the next day in impaired function of the frontal cortex, as
measured by electroencephalograph (EEG) potentials." SFN:
Losing Sleep Impairs Frontal Cortex Function "'When you are sleep-deprived,
you are recruiting more parietal resources [because the frontal lobes are
impaired],' said Dr. Godbout. 'The parietal lobe counterbalances for lack
of frontal function,' Dr. Godbout stated. The frontal cortex is thought
to govern so-called executive function, such as decision making, which
matures only at the end of adolescence." SFN:
Losing Sleep Impairs Frontal Cortex Function "Six studies on sleep/wake
patterns and circadian rhythms were carried out. In summary: (1) Adrenaline excretion, self-rated
activation, and body temperature rhythms ·
Persisted during sleep
deprivation, ·
Resisted adjustment to
rotating shift work, but ·
Adjusted rather well to
permanent night work. Noradrenaline ·
Adjusted to most
schedules and lost its rhythm during sleep deprivation. ·
When night sleep
was reintroduced the noradrenaline rhythm reappeared while the
existing adrenaline rhythm was accentuated. (2) Exposure to a performance stressor
at the trough raised adrenaline to daytime levels. An equally
large response was seen at the peak. (3) Interindividual [occurring between two
and four individuals] day-to-day consistency of 3 and 24 hour levels was high
for both catecholamines [neurotransmitters that activate--examples are
dopamine, epinephrine and norepinephrine]. Intraindividual [being or
occurring within the individual] consistency of the 24-hour pattern
was high for adrenaline but low for noradrenaline. Cosine
estimates of adrenaline phase showed a considerable intraindividual
consistency while interindividual consistency was poor. Noradrenaline had
poor cosine fit. (4) Sleep deprivation did not change
catecholamine excretion
either during the vigil or during recovery sleep. (5) It was concluded that adrenaline
excretion, rated alertness, and body temperature exhibited self-sustained
circadian rhythms which made adjustment to new sleep/wake patterns
very difficult, and that the noradrenaline excretion rhythm depended on
exogenous [outside the body] factors." ·
Stedman's Online Medical Dictionary, 27th Edition:
Noradrenaline |