Insomnia disorder is characterized by chronic dissatisfaction with sleep quantity or quality
that is associated with difficulty falling asleep, frequent nighttime awakenings with difficulty …

Functional neuroimaging studies have started unravelling unexpected functional attributes
for the posteromedial portion of the parietal lobe, the precuneus. This cortical area has …

Background: Of all the psychiatric disorders associated with insomnia, depression is the
most common. It has been estimated that 90% of patients with depression complain about …

Sleep researchers in different disciplines disagree about how fully dreaming can be
explained in terms of brain physiology. Debate has focused on whether REM sleep …

The negative effects of sleep deprivation on alertness and cognitive performance suggest
decreases in brain activity and function, primarily in the thalamus, a subcortical structure …

Several theories claim that dreaming is a random by-product of REM sleep physiology and
that it does not serve any natural function. Phenomenal dream content, however, is not as …

No current hypothesis can explain why animals need to sleep. Yet, sleep is universal, tightly
regulated, and cannot be deprived without deleterious consequences. This suggests that …

Sleep can be addressed across the entire hierarchy of biological organization. We discuss
neuronal-network and regional forebrain activity during sleep, and its consequences for …

Recent blood oxygenation level dependent functional MRI (BOLD fMRI) studies of the
human brain have shown that in the absence of external stimuli, activity persists in the form …

Functional neuroimaging using positron emission tomography has recently yielded original
data on the functional neuroanatomy of human sleep. This paper attempts to describe the …