Effects of beta-amyloid accumulation on neural function during encoding across the adult lifespan.
Abstract
Limited functional imaging evidence suggests that increased beta-amyloid deposition is associated with alterations in brain function, even in healthy older adults. However, the majority of these findings report on resting-state activity or functional connectivity in adults over age 60. Much less is known about the impact of beta-amyloid on neural activations during cognitive task performance, or the impact of amyloid in young and middle-aged adults. The current study measured beta-amyloid burden from PET imaging using (18)Florbetapir, in a large continuous age sample of highly-screened, healthy adults (N=137; aged 30-89 years). The same participants also underwent fMRI scanning, performing a memory encoding task. Using both beta-amyloid burden and age as continuous predictors of encoding activity, we report a dose-response relationship of beta-amyloid load to neural function, beyond the effects of age. Specifically, individuals with greater amyloid burden evidence less neural activation in bilateral dorsolateral prefrontal cortex, a region important for memory encoding, as well as reduced neural modulation in areas associated with default network activity: bilateral superior/medial frontal and lateral temporal cortex. Important...Continue Reading
References
Episodic memory loss is related to hippocampal-mediated beta-amyloid deposition in elderly subjects.
Citations
Related Concepts
Related Feeds
Cajal Bodies & Gems
Cajal bodies or coiled bodies are dense foci of coilin protein. Gemini of Cajal bodies, or gems, are microscopically similar to Cajal bodies. It is believed that Cajal bodies play important roles in RNA processing while gems assist the Cajal bodies. Find the latest research on Cajal bodies and gems here.
Alzheimer's Disease: APP
Amyloid precursor protein (APP) proteolysis is critical for the development of Alzheimer's disease, a neurodegenerative disease associated with accumulation of amyloid plaques in the brain. Here is the latest research on APP and Alzheimer's disease.
Alzheimer's Disease: Amyloid Beta
Alzheimer's disease is a neurodegenerative disease associated with the accumulation of amyloid plaques in the brain; these plaques are comprised of amyloid beta deposits. Here is the latest research in this field.
Alzheimer's Disease: Neuroimaging
Neuroimaging can help identify pathological hallmarks of Alzheimer's disease (AD). Here is the latest research on neuroimaging modalities, including magnetic resonance imaging and positron emission tomography, in AD.