Brain Cell Density Remains Constant Even as Brain Shrinks With Age

Posted on June 15, 2015

A new study on the human brain has found that brain cell density remains constant even as the brain shrinks with age. The study was conducted by researchers at the University of Illinois at Chicago using magnetic resonance images (MRI) of the brains of cognitively normal young and old adults. A 9.4-Tesla MRI machine was used which has a magnetic field three times stronger than current MRI machines found in doctor's offices.

The UIC researchers say their study is the first to show that cell density is preserved throughout the brain during normal aging. The scientists also say the study suggests the maintenance of brain cell density may protect against cognitive impairment.

Dr. Keith Thulborn, director of MRI research in the UIC College of Medicine and lead author of the report, says in a statement, "The information provided by these 9.4-Tesla scans may be very useful in helping us to detect tiny losses of brain cells and the reduction in cell density that characterizes the early stages of neurodegenerative diseases that can take decades to develop before symptoms appear, like Alzheimer's disease. If we can identify when Alzheimer's pathology starts, the efficacy of new drugs or other interventions to slow or prevent Alzheimer's disease can be tested and monitored when the disease starts, instead of after it's developed for 20 or 30 years and becomes clinically apparent."

The brains of 49 cognitively normal adults ranging in age from 21 to 80 were observed using the 9.4 Tesla MRI for the study. The advanced MRI measures sodium ions. Sodiums ions are present throughout the human body and are pumped in and out of neurons to generate the electric potentials needed to spark nerve impulses. Concentrations of sodium in the brain reflect neuron density. Areas of lower sodium concentrations reflect high neuron density whereas higher concentrations may indicate the loss of cells.

A research paper on the study was published in the journal, NMR in Biomedicine.



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