Memory Linked to Shrinking Frontal Lobe and Poor Sleep Quality

Sleep and Memory

Image UC Berkeley / National Institutes of Health

Researchers from the Sleep and Neuroimaging Laboratory at the University of California at Berkeley have confirmed that loss of memory as we get older is linked to poor sleep quality and atrophy of the brain’s prefrontal lobe.

While previous studies have confirmed the relationship between cognition and sleep quality, the Berkeley researchers, led by UC Berkeley associate professor of psychology and neuroscience Matthew Walker, Ph.D., compared memory, sleep quality and frontal lobe size among 18 healthy young adults and 15 healthy older adults.

The young adults were primarily in their 20s while the older adults were primarily in their 70s. Before they went to bed they were given 120 word sets to remember. They were tested for memorization of the word sets.

As they were sleeping, brainwave tests using electroencephalopathy (EEG) equipment were measured. This measures the brain’s waveforms, illustrating the extent and potential lack of slow wave activity associated with good quality sleep.

In the morning the subjects were then tested once again on the same word pairs, while being given MRI scans (magnetic resonance imaging).

(Note: This article does not attest to the long-term safety of repeated MRI scans – See Electromagnetic Health for more information on potential MRI scan risks).

In comparing the MRI scans with the EEG tests, the researchers found an association between the lack of slow wave activity during sleep and the deterioration of the middle frontal lobe of the prefrontal cortex.

On average the older adults had 75% less slow wave sleep. In other words, their sleep quality was 75% worse than the younger subjects. Their word recall was also 55% worse than the word recall of the younger subjects.

According to the researchers, this illustrated that the increased slow wave sleep allowed the younger subjects to likely more efficiently transfer memories from the hippocampus to the prefrontal cortex.

“What we have discovered is a dysfunctional pathway that helps explain the relationship between brain deterioration, sleep disruption and memory loss as we get older,” commented Dr. Walker. “When we are young, we have deep sleep that helps the brain store and retain new facts and information. But as we get older, the quality of our sleep deteriorates and prevents those memories from being saved by the brain at night.”

Learn hundreds of natural strategies to increase sleep quality.

This is not the first study that has connected frontal lobe function with sleep quality. In 2001, researchers from Liverpool’s John Moores University found a link between the two.

The fact that the frontal lobe decreases in size as a person ages has also been established in previous research. In 2009, University of Oslo researchers found that the prefrontal cortices deteriorated an average of 0.5% among healthy adults, and generally more among adults with mild Alzheimer’s disease.

By 2007, several studies had thoroughly linked sleep quality to poor lack of cognitive health, as summarized in a large review of research at Finland’s University of Turku.

And more recent research – such as a late 2012 study from Germany’s Max Planck Institute of Psychiatry – has confirmed that academic performance is linked with sleep quality. In this study, 144 medical students underwent sleep studies while before taking board exams. The research found that poor performance was connected to poor sleep quality among the students.

The association between the three – sleep quality, frontal lobe size and memory – was confirmed in this study.

REFERENCES:

Mander BA, Rao V, Lu B, Saletin JM, Lindquist JR, Ancoli-Israel S, Jagust W, Walker MP. Prefrontal atrophy, disrupted NREM slow waves and impaired hippocampal-dependent memory in aging. Nat Neurosci. 2013 Jan 27.

Jones K, Harrison Y. Frontal lobe function, sleep loss and fragmented sleep. Sleep Med Rev. 2001 Dec;5(6):463-475.

Ahrberg K, Dresler M, Niedermaier S, Steiger A, Genzel L. The interaction between sleep quality and academic performance. J Psychiatr Res. 2012 Dec;46(12):1618-22.

Alhola P, Polo-Kantola P. Sleep deprivation: Impact on cognitive performance. Neuropsychiatr Dis Treat. 2007;3(5):553-67.

Fjell AM, Walhovd KB, Fennema-Notestine C, McEvoy LK, Hagler DJ, Holland D, Brewer JB, Dale AM. One-year brain atrophy evident in healthy aging. J Neurosci. 2009 Dec 2;29(48):15223-31.

Case Adams is a California Naturopath with a PhD in Natural Health Sciences, and Board Certified Alternative Medicine Practitioner. He has authored 26 books on natural healing strategies. “My journey into writing about alternative medicine began about 9:30 one evening after I finished with a patient at the clinic I practiced at over a decade ago. I had just spent the last two hours explaining how diet, sleep and other lifestyle choices create health problems and how changes in these, along with certain herbal medicines and other natural strategies can radically yet safely turn ones health around. As I drove home that night, I realized I needed to get this knowledge out to more people. So I began writing about health with a mission to reach those who desperately need this information. The strategies in my books and articles are backed by scientific evidence along with wisdom handed down through traditional medicines for thousands of years.” Case connects with the elements by surfing, hiking and being a beach bum.

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