May 19, 2011 13:42 GMT  ·  By
Sleep is essential to promoting memory formation and stopping cognitive decline
   Sleep is essential to promoting memory formation and stopping cognitive decline

For centuries, scientists have observed that depriving people of sleep can result in memory and cognitive impairments. However, the reason why that happened remained unclear. Now, researchers provide a new explanation for this peculiar phenomenon.

One of the things that experts noticed in all species of animals that need to sleep is that depriving them of this necessity results in increased levels of the nucleoside adenosine in their brains. The team, therefore thought that this would be a great place to start.

In humans, elevated concentrations of adenosine are usually found in the hippocampus, an area of the brain that previous studies have associated with memory function. In the new study, experts carried out research on animal models, so that they could better control the parameters of the experiment.

“For a long time, researchers have known that sleep deprivation results in increased levels of adenosine in the brain, and has this effect from fruit flies to mice to humans,” explains Dr. Ted Abel.

“There is accumulating evidence that this adenosine is really the source of a number of the deficits and impact of sleep deprivation, including memory loss and attention deficits,” the expert goes on to say.

“One thing that underscores that evidence is that caffeine is a drug that blocks the effects of adenosine, so we sometimes refer to this as ‘the Starbucks experiment',” says the scientist, who is a professor of biology at the University of Pennsylvania.

He is also the leader of the UP research team that carried out the investigation. Details of the work were published in the latest issue of the esteemed medical Journal of Neuroscience. For this study, two groups of mice were deprived of sleep, but the effects this had were analyzed in different ways.

“To be able to reverse a particular aspect of sleep-deprivation, such as its effect on memory storage, we really want to understand the molecular pathways and targets,” Abel explains. This is precisely what the team managed to do in these experiments.

“Here, we’ve identified the molecule, the cellular circuit and the brain region by which sleep deprivation affects memory storage. Our sleep deprivation experiments are the equivalent of losing half of a night’s sleep for a single night,” the researcher explains.

“Most of us would think that’s pretty minor, but it shows just how critical the need for sleep is for things like cognition,” he explains, quoted by PsychCentral. These findings again underline the necessity of people getting enough sleep every night.