Perinatal fluoxetine exposure disrupts the circadian response to a phase-shifting challenge in female rats.

Rationale: Selective serotonin reuptake inhibitor (SSRI) antidepressants are increasingly prescribed during pregnancy. Changes in serotonergic signaling during human fetal development have been associated with changes in brain development and with changes in affective behavior in adulthood. The suprachiasmatic nucleus (SCN) is known to be modulated by serotonin and it is therefore assumed that SSRIs may affect circadian rhythms.

Alzheimer's disease pathogenesis: The role of disturbed sleep in attenuated brain plasticity and neurodegenerative processes.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive impairments. The classical symptoms of the disease include gradual deterioration of memory and language. Epidemiological studies indicate that around 25-40% of AD patients have sleep-wake cycle disturbances.

The reverse translation of a quantitative neuropsychiatric framework into preclinical studies: Focus on social interaction and behavior.

Following the Research Domain Criteria (RDoC) concept, major brain circuits are conserved in evolution and malfunctioning of a brain circuit will lead to specific behavioral symptoms. Reverse translation of patient-based findings from Alzheimer's disease (AD), schizophrenia (SZ) and major depression (MD) patients to preclinical models accordingly can be a starting point for developing a deeper understanding of the functional circuit biology and contribute to the validation of new hypotheses for therapeutic intervention in patients. In the context of the EU funded PRISM project, a preclinical test battery of tasks has been selected and aligned with the clinical test battery.

Melanopsin- and L-cone-induced pupil constriction is inhibited by S- and M-cones in humans.

The human retina contains five photoreceptor types: rods; short (S)-, mid (M)-, and long (L)-wavelength-sensitive cones; and melanopsin-expressing ganglion cells. Recently, it has been shown that selective increments in M-cone activation are paradoxically perceived as brightness decrements, as opposed to L-cone increments. Here we show that similar effects are also observed in the pupillary light response, whereby M-cone or S-cone increments lead to pupil dilation whereas L-cone or melanopic illuminance increments resulted in pupil constriction.

Linking Light Exposure and Subsequent Sleep: A Field Polysomnography Study in Humans.

Study Objectives: To determine the effect of light exposure on subsequent sleep characteristics under ambulatory field conditions.

Methods: Twenty healthy participants were fitted with ambulatory polysomnography (PSG) and wrist-actigraphs to assess light exposure, rest-activity, sleep quality, timing, and architecture. Laboratory salivary dim-light melatonin onset was analyzed to determine endogenous circadian phase.

Sleep-Wake Patterns and Cognition of Older Adults with Amnestic Mild Cognitive Impairment (aMCI): A Comparison with Cognitively Healthy Adults and Moderate Alzheimer's Disease Patients.

Objective: Age-related cognitive impairment and the prevalence of neurodegenerative disease contribute to decreasing quality of life in affected individuals and their families as well as demand considerable societal responsibility. Sleep supports overall brain activity and contributes to both physical and mental health. As a result, sleep is an attractive target for exploring ways to promote health in accelerated cognitive aging.

Daily Light Exposure Patterns Reveal Phase and Period of the Human Circadian Clock.

Light is the most potent time cue that synchronizes (entrains) the circadian pacemaker to the 24-h solar cycle. This entrainment process is an interplay between an individual's daily light perception and intrinsic pacemaker period under free-running conditions. Establishing individual estimates of circadian phase and period can be time-consuming.