Researchers have identified average levels of biological and anatomical brain changes associated with Alzheimer's disease over thirty years before symptoms appear. In those with genetic risk factors for Alzheimer's, researchers found changes in cognitive performance up to 15 years before becoming symptomatic. Changes in Tau levels in the cerebral spinal fluid appeared up to 34 years before dementia symptoms occurred, and physical changes to the medial temporal lobe were apparent up to 9 years before cognitive impairment was apparent.
LATE, a form of dementia that appears in the oldest-old is often mistaken for Alzheimer's disease, but the brain pathology is very different. The protein TDP-43 appears to play a significant role in the development of LATE. The neurodegenerative disease may progress more gradually than Alzheimer's, but when combined with Alzheimer's disease (a common combination), appears to cause a more rapid decline than either would alone.
Study reports declarative memory depends upon conscious knowledge of what has been previously learned. Researchers discovered conscious knowledge is compromised in those with damage to the hippocampus. The findings shed new light on how the hippocampus controls the process of memory.
A new study reports older adults exhibit greater eye movements, but this does not correlate with an increase in brain activity patterns. Researchers say, while the eyes and brain are taking in environmental information, the link to creating memories of what is seen weakens over a life time.
A new EEG and fMRI study of epilepsy patients may reveal clues about the origins of consciousness. Researchers report activity in the frontal lobe changes 2 seconds before patients report an alteration in perception, and activity in the medial temporal lobe changes one second prior to them reporting.
Stimulating specific regions of the brain can help to improve memory and word recall in those with severe epilepsy, a new Nature Communications study reports.