The Cause of Internet and TV Addiction?
"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."
"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
· 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."
"'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."
"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.
· 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."