Try mind over matter - or safe socks

By MARTIN JOHNSTON health reporter

"Oh please, darling, let me slip over to your side of the bed. My feet are so cold I can't get to sleep."

This night-time appeal has struck a chord with researchers investigating the physical and mental links between insomnia and cold feet.

Now they are going further and trying to coach people into thinking warm thoughts in a mind-over-matter bid to help them conquer sleepless nights.

Dr Kurt Lushington, of the University of South Australia, says cold hands and feet in bed have been a common complaint of insomniacs visiting his sleep research centre.

"One of the things that marked whether they were going to sleep or not was whether their hands and feet were cold."

Blood vessels in the hands, feet and face open shortly before sleep, warming up these body parts, he says. This radiates heat, allowing the body's core temperature to drop.

He says up to one in five people are afflicted by insomnia lasting more than six months. They take more than 30 minutes to nod off, or wake for at least that long on three or more nights a week. They sleep less than 6 1/2 hours a night on average and have a reduced daytime performance.

Dr Lushington told an Auckland sleep disorders conference of his team's experiment on 19 normal sleepers. Their hands were connected to monitors and they were taught to raise and lower their hand temperature mentally.

Dr Tony Fernando, an Auckland Medical School senior psychiatry lecturer, said it was promising research but had a long way to go. Bad sleepers had nothing to lose by warming up before bed - or pulling on socks.