Ex3 L15 The Aging Brain Flashcards
What becomes more difficult vs. stays easy with age?
become difficult:
- remembering names
- multi tasking
- focusing for long periods
retain ability to:
- learn new tasks
- create new memories
- improve vocabulary
What are the four big changes that happen to the brain with age?
- reduced brain volume (especially around the lateral ventricles)
- decreased neurons and speed of neurotransmission (result of ox stress, mito dysfunction, and altered metabolism)
- reduced blood flow
- increased inflammation
What are the phases of memory?
perceptual, short term/working, long term (which splits into semantic and remote)
Describe perceptual memory
- very short lasting (seconds)
- sensory memory, stored momentarily in sensory regions of the brain
- relies on primary sensory regions
- sensory areas that control perceptual memory have little change with age (however, senses can change due to changes in the receptors)
Describe short term/working memory
- info that is moved from perceptual to working stores
- slightly longer (15-45 seconds)
- relies on prefrontal cortex (important for concentration)
- aging leads to short term memory deficits as a result of cell loss and reduced speed of neurotransmission in the PFC
Older people are slower to —— but better able to ——
- slower reasoning through decisions
- better able to make gut decisions
Describe long term memory
- requires learning of information using strategies
- minutes to years
- relies on hippocampus
- requires storage AND retrieval
- aging leads to long term memory deficits as a result of less activity/cells/shrinkage of the hippocampus
- less cells = less area for storage = more overlap = interference and confusion
What are the main areas that shrink and lose activity with age?
hippocampus and prefrontal cortex
Describe semantic memory
- vocabulary and facts
- lose details regarding time and place of memory acquisition (lose context)
- relies on temporal lobe
- mostly preserved with age
Describe remote memory
- memory from the distant past
- important for story-telling, often includes the time and place that the event occurred
- relies on the temporal lobe
- typically preserved with age
Is semantic or remote memory better preserved with age?
remote - semantic loses some context, but both are generally retained pretty well
What changes do we see in aging neurons?
- degenerating dendritic tree with less/shorter branches
- more ROS, less calcium regulation, less activation
- mitochondrial dysfunction leads to more ROS
- ER makes misfolded proteins that lead to more ROS
- axons have disorganized myelin sheaths that impede conduction
- less NAD+ in the axons that cause dysfunctional nutrient sensing
- bad neurons lead to bad neuroglia
What glial cell changes do we see in the aging brain?
microglia:
- inflammatory, more M1, but less phagocytic activity
astrocytes:
- inflammatory, decreases processing of “trash”, and more susceptible to ROS
oligodendrocytes:
- get worn out, broken and incomplete myelin sheaths, and move slower causing slower remyelination rates
What is normal cognitive aging?
graduate, age related decline in memory, conceptual reasoning, and cognitive processing speed
What is the difficulty with diagnosing age-related cognitive diseases?
- they are difficult to distinguish from normal cognitive decline
- BUT they are easiest to treat/manage if they are caught early on - so we want to catch them early (which is hard)
