First, there may be a brief cessation or reduction of breathing when falling asleep as the sleeper waxes and wanes between sleep and wakefulness and their differing control mechanisms.

首先，睡眠者在半梦半醒及不同调节机制之间转换时进入睡眠状态，呼吸可能短暂地停止或减少。

youdao

In those terrible hours between sleep and wakefulness, I have visions.

在睡着和醒来之间的那些可怕的时间里，我常常出现幻觉。

youdao

A neurotransmitter associated with voluntary movement, sleep and wakefulness.

一种神经递质与自主运动、睡眠有关。

youdao

The team was looking for a natural clock in the body that controls sleep and wakefulness.

VOA: special.2009.08.26

And they will study whether it is involving in controlling sleep quantity alone, or also what scientists call the "wakefulness-behavioral drive."

VOA: special.2009.08.26

The hypocretin system is known to play a key role in controlling sleep and wakefulness.

BBC: NEWS | Health | Immune system link to narcolepsy

Rothoron, the gossamer bridge suspended between sleep and wakefulness.

NPR: 'Ancestor Stones:' Life and War in Sierra Leone

And when sleeping pills aren't enough to help patients stay alert, a wakefulness drug called Provigil is already approved for excessive daytime sleepiness caused by narcolepsy, sleep apnea and shift-work sleep disorder--the exhaustion brought on in some people by working the night shift.

FORBES: Sleep On Demand