In most cases, the health risks from sleep loss only become serious after years.

And some people seem to be more tolerant of short-term sleep loss.

But the causes of sleep loss aren't always so clear.

As a cause of sleep loss, this is often a surprise to people.

This would make sense if the consequences of sleep loss were more benign.

But the penalties for what might be called catastrophic sleep loss are well known.

Has sleep loss taken a toll on your emotional health?

Both fast and slow responses were slower after sleep loss.

Worse still, they say, the effects of sleep loss are cumulative.

Here are 10 surprising - and serious - effects of sleep loss.