Brain cell changes may cause sleep troubles in aging

April 24, 2012

Older animals show cellular changes in the brain "clock" that sets sleep and wakeful periods, according to new research in the April 25 issue of The Journal of Neuroscience. The findings may help explain why elderly people often experience trouble sleeping at night and are drowsy during the day.

Like humans, mice experience shifts in daily activities and as they age. To find out why, researchers directed by Johanna Meijer, PhD, at the Leiden University Medical Center in the Netherlands studied the electrical activity of cells in the (SCN), an area of the brain responsible for setting sleep-wake cycles.

Consistent with previous studies, the researchers found aged mice showed disrupted sleep behavior and weakened brain network activity in the SCN. But Meijer and colleagues also found changes occurring in individual SCN cells, not just in their networks.

"In fact, the changes at the single-cell level were more severe than the changes at the network level," said Meijer. This represents a shift in understanding of aging's effects on the brain.

The researchers made electrophysiological recordings from isolated SCN neurons, a difficult experiment given the advanced age of the animals and the small size of this type of neuron. They found aged SCN neurons lack day-night rhythms in some membrane properties. In addition, the team identified age-related reductions of certain potassium currents that are important to the neurons' rhythmic firing.

Because potassium and other can be manipulated with drugs, "This work provides a new target for potential therapeutic interventions that can mitigate the age-related decline in the sleep-wake cycle," said Christopher Colwell, PhD, an expert in circadian clock function at the University of California, Los Angeles, who was not involved in the study.

Explore further: Study shows new evidence of age-related decline in the brain's master circadian clock

Related Stories

Recommended for you

Chatter in the deep brain spurs empathy in rats

June 23, 2017

It's a classic conundrum: while rushing to get to an important meeting or appointment on time, you spot a stranger in distress. How do you decide whether to stop and help, or continue on your way?

The neural relationship between light and sleep

June 23, 2017

Humans are diurnal animals, meaning that we usually sleep at night and are awake during the day, due at least in part to light or the lack thereof. Light is known to affect sleep indirectly by entraining—modifying the length ...

How pheromones trigger female sexual behavior

June 22, 2017

A study by a group of Japanese scientists showed how a male pheromone in mice enhances sexual behaviors in females—and how it may enhance a different behavior, aggression, in males—by identifying distinct neural circuits ...

Coupling of movement and vision

June 22, 2017

In a study published in Cell, Georg Keller and his group shed light on neural circuits in the cortex that underlie the integration of movement and visual feedback. They identified a mechanism in the visual cortex responsible ...

Forgetting can make you smarter

June 21, 2017

For most people having a good memory means being able to remember more information clearly for long periods of time. For neuroscientists too, the inability to remember was long believed to represent a failure of the brain's ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.