Can’t sleep? Blame your ageing brain

We all know the feeling. You flop into bed exhausted with the hope that you’ll be fast asleep within minutes. But two hours later you’re still wide awake. You’re stressed and anxious about the diminishing hours before the alarm drags you into another busy day. And because you’re stressed and anxious you’re even less likely to nod off.

Researchers at the University of California, Berkeley, believe our sleep patterns are a function of the way our brains pick up and react to signals about how tired we are. As we age, the way our brains interpret sleep signals changes dramatically.

Older people seem to struggle more with sleep. However, it’s a common misconception that the elderly need less sleep. Studies have consistently shown that sleep needs are similar in adults in different stages of life. In recent years, lack of sleep has also been linked to health conditions such as heart disease, diabetes and obesity; it also heavily influences our mental well-being. Generally, 1 in 4 people feel sleepy during the day because of a lack of sleep, and men suffer more from disrupted sleep later in life than women.

New research suggests that as we age, we start losing the neuronal connections that pick up on sleepiness cues. Researchers from Berkeley published a paper in the journal Neuron, saying that we are less able to get the sleep we need because of changes in our brains. The lead author of the study, Matthew Walker, told Popular Science: “It’s almost like a radio antenna that’s weak. The signal is there, but the antenna just can’t pick it up.”

Another misconception is that “sleepiness receptors” only decline in middle age. “Sleep architecture” as neurologists call it starts changing when people enter their 20s. In their 40s, overall, they go to bed earlier and wake up earlier. They also find falling asleep more difficult and complain of broken sleep and of waking up feeling tired. When a person hits 50, they are only getting half of the deep sleep they got in their youth. By 70, sleep is really not restful and waking up several times during the night is the norm. It’s also a cliché, but the frequency of naps during the day increases by 25% in people over 75 years old. Half of those naps are unintended.

From an evolutionary perspective, sleep doesn’t make any sense. It create a vulnerabilty to predators and wastes precious time when you could be doing other things. Sleep is still something of a mystery to scientists, but they know it’s vital for brain cells. So, what can we do about the effects of ageing on our ability to sleep? For now, not much. The findings on “sleepiness connectors” in the brain may open new pathways for more effective sleeping medications. The Californian team will also look into the possibilities of creating therapies with electric brain stimulation

In the meantime, the advice for insomnia remains unchanged: avoid caffeine, sleep in a cool room, and try to relax before bedtime.