L14 Flashcards
When rosenthal et al. initially studied SAD, they recruited ___ patients from a local community with a history of ___ and who had experienced for at least __ consecutive years, depression that developed during the ___ or ____ and remitted during the following spring or summer.
29, MDD, 2, fall, winter
Symptoms of SAD included sadness, ___, and irritability, decreased __ ____, changes in appetite and a craving for _____, increased total ____ time, and daytime ____.
anxiety, physical activity, carbohydrates, sleep, drowsiness
Rosenthal discovered that the percentage of subjects experiencing depression in ____ was 100%, when the daily ____ and _____ for the town was the lowest of all months.
january, photoperiod, temperature
Subjects in rosenthal’s experiment got 2 weeks of ____ ____ 3 hours before dawn or 3 hours after dusk. They either received a ____ light (daytime sunlight mimic) or a dim ____ light (mimics sunrise / ____ light). There was a decrease in symptoms with the light mimicking ______ light, but not the dim yellow light.
light therapy, blue, yellow, sunset, daytime
type of recurrent major depression, wherein depression begins and ends during a specific season each year
seasonal affective disorder
mild symptoms of SAD can be considered the ___ ___, or ____ ____. Severe symptoms of SAD are often debilitating symptoms seen in non-seasonal ____.
winter blues, subsyndromal SAD, MDD
Hypotheses on SAD pathophysiology include ____ ___, ____ function, and ____
circadian rhythms, neurotransmitter, genetics
Circadian rhythmicity is maintained by the central pacemaker in the ____, the ____, which entrains internal circadian rhythms to external time cues (____). Circadian ____ occurs when there is asynchrony between the SCN rhythm and ____.
hypothalamus, SCN, zeitgeber, misalignment, behaviour
______ displays robust circadian rhythm and plays a critical role in synchronizing the sleep-wake cycle with the ____ cycle. It peaks a little after ____, and ___ in the morning.
melatonin, light-dark, midnight, decreases
Circadian rhythm phase of melatonin can be described by the ___ ___ ______ _____, or the temporal onset of melatonin rise. Light exposure in the evening results in a ____ ____ of melatonin rhythm. If the wake-up time remains constant, but light exposure is still given in the evening, the phase-delayed melatonin rhythms results in a smaller __ ____ with the sleep wake cycle (has shorter rise and fall). Light exposure in the ___ can correct a phase-delayed rhythm by causing a ______
dim light melatonin onset, phase delay, phase angle, morning, phase-advance
melatonin is a small, _____, ______ ____ derived hormone that is primarily synthesized and secreted on demand by ____ in the pineal gland. It is metabolized quickly, with a half life of ___ minutes, and production is tightly regulated by ________ _____ release.
non polar, amino acid, pinealocytes, 30, sympathetic norepinephrine
when there is light, the light reaches the ___ ____ ____, then travels to the ___ which inhibits the ____.
retinal hypothalamic tract, SCN, PVN
In the darkness, the RHT has ___ ____, leading to no activation in the SCN, and ___ of the PVN. This PVN activity travels to the _____ ___ ____, which release ____ onto alpha-1 or ____ receptors on the ______. This then leads to the activation of ___ and subsequently ____, which activates ____ directly or indirectly by _____. ____ returned to the cell by monoamine transporters is converted to ______. This product is then converted to ___ by a protein ____ by PKA. Then melatonin diffuses into the bloodstream
no activation, disinhibition, sympathetic nervous system, NE, beta-1, pinealocyte, DAG/IP3, PKC, PKA, cAMP, serotonin, N-acetylserotonin, melatonin, phosphorylated
Exposure to a ____ light induces a reduction in melatonin release, while this is not seen in a ___ shifted light.
white/blue, green
a ____ light perception is not necessary for photoregulation of melatonin release. This is shown in patients with ___ ____, who have a damaged _____ ______. In these people, light does ___ affect melatonin release, and they lack a typical ___ hour circadian rhythm. However, patients with ___ ___ ____, where the retinal-hypothalamic tract is preserved, light induced a ___ of melatonin release, even though the patient had no ____ awareness of the light
conscious, congenital glaucoma, retinal-hypothalamic tract, not, 24, congenital retinal dystrophy, suppression, conscious
Photosensitivity ___ with age. Older people wake up ___ in the morning and have ___ during the day
decrease, earlier, naps