Home » Disorders » Alzheimers » Memory Loss in Alzheimer’s

Memory Loss in Alzheimer’s

Brain ScanResearchers may have discovered how the protein Amyloid-beta(AB) impairs memory in Alzheimer’s patients.

AB, which is known to accumulate in the brains of Alzheimer patients, has long been a focus of research into the causes and treatment of the disease.

In a study published in the journal Neuron, scientists found that A-beta triggers abnormal overexcitation of the very brain networks that are responsible for learning and memory.

“Such abnormal network activity in Alzheimer’s patients was thought to be a collateral or secondary event caused by the degeneration of nerve cells,” said Jorge J Palop, PhD, a Gladstone Institute research scientist and lead author of the study.

“But our study suggests that this activity may actually be a primary effect of A-beta and an early determinant of cognitive failure.”

The Gladstone team used several genetically engineered mouse models of AD in which memory deficits are triggered by a human gene that causes high levels of A-beta.

They discovered that high levels of A-beta induce an insidious type of seizure activity in learning and memory centers that is not accompanied by the usual twitching and jerking movements seen in many forms of epilepsy.

In fact, it took sophisticated brain wave recordings in freely behaving mice by electroencephalography (EEG) and telemetry to detect the seizure activity.

“We were really surprised by these findings because A-beta had previously been suspected to primarily suppress neuronal activity,” said Lennart Mucke, MD, GIND director and professor of neurology and neuroscience at the University of California, San Francisco (UCSF), and senior author of the study.

“This abnormal brain activity could play an important role in the development of Alzheimer-related cognitive impairments.”

Physicians have long recognized that Alzheimer patients have a higher incidence of convulsive seizures than reference populations.

The new study indicates that A-beta is to blame for this problem and raises the disconcerting possibility that these patients may also have non-convulsive seizures that could easily escape detection by standard clinical exams. The investigators are eager to test this hypothesis in a planned follow-up study of human subjects.

“Our results have important therapeutic implications, because the prevention and reversal of non-convulsive seizure activity has not yet been a major focus of clinical trials in Alzheimer’s disease. Our results suggest that the suppression of this activity might prevent and possibly even reverse cognitive impairments induced by high levels of A-beta,” said Dr. Mucke.

Source: Gladstone Institutes

Memory Loss in Alzheimer’s

Rick Nauert PhD

Rick Nauert, PhDDr. Rick Nauert has over 25 years experience in clinical, administrative and academic healthcare. He is currently an associate professor for Rocky Mountain University of Health Professionals doctoral program in health promotion and wellness. Dr. Nauert began his career as a clinical physical therapist and served as a regional manager for a publicly traded multidisciplinary rehabilitation agency for 12 years. He has masters degrees in health-fitness management and healthcare administration and a doctoral degree from The University of Texas at Austin focused on health care informatics, health administration, health education and health policy. His research efforts included the area of telehealth with a specialty in disease management.

APA Reference
Nauert PhD, R. (2015). Memory Loss in Alzheimer’s. Psych Central. Retrieved on May 23, 2018, from https://psychcentral.com/news/2007/09/07/memory-loss-in-alzheimers/1245.html

 

Scientifically Reviewed
Last updated: 6 Oct 2015
Last reviewed: By John M. Grohol, Psy.D. on 6 Oct 2015
Published on PsychCentral.com. All rights reserved.