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Video transcript

so dementia is this general term we use when someone starts having trouble remembering communicating and understanding and Alzheimer's disease is a specific type of dementia that accounts for about sixty to eighty percent of all dementia cases but what about the other twenty to forty percent well the second most common type accounting for about 20 to 30 percent of dementia cases is called vascular dementia so what do all the cells in your body regardless of what they do need to survive oxygen they all need oxygen your brain cells are definitely no different actually they're probably the biggest oxygen hogs in the body every time our heart beats we pump about 20 to 25 percent of that blood straight to our brain cells since there are so many brain cells or neurons that need so much oxygen you can imagine that the brain is especially vulnerable and sensitive to a lack in blood flow so when they don't get that oxygen or get less of it they can be damaged or even start to die off so if for example your cells in your temporal lobe don't get enough oxygen and start to die off it's going to be more difficult to remember things and form new memories because that's the area of your brain that controls those things and so this is why we call it vascular dementia where the vascular part refers to the blood supply in the blood vessels supplying the brain if there's any lack in blood flow to the brain as a result of a lowered blood supply then loss of brain cells can follow and loss of certain mental functions with vascular dementia changes in thinking skills can happen suddenly following some sort of sudden damage from a major stroke maybe which is an interruption in the blood supply to the brain also though changes in thinking skills can come about gradually due to minor strokes or as small vessels supplying the brain become blocked leading to a more progressive damage so because it's related to your blood supply and your cardiovascular system risk factors are very similar to the ones that could also raise your risk for heart diseases blood vessel problems and stroke some of these are things like smoking high blood pressure lack of exercise obesity and an unhealthy diet all right so that's the second most common type of dementia the third most common type is called dementia with Lewy bodies and this accounts for about ten to twenty five percent of all dementia cases and this type is caused by abnormal protein structures forming inside your neurons called Lewy bodies which are named after dr. Frederick Louie who discovered them in the early 1900s now these Lewy bodies are actually accumulated bits of a protein called alpha synuclein and you can find these guys hanging out in your brain cells or your neurons these alpha synuclein proteins are found widely throughout the brain but their exact function isn't fully understood yet one thing we do know is that when your cells can't properly process these proteins they start to accumulate and sort of build up forming these Lewy bodies and ultimately end up damaging the cell symptoms of Lewy body dementia include problems with thinking and memory movements in trembling hallucinations and even physically acting out dreams like sleepwalking talking or sleep kicking similarly to Alzheimer's scientists have yet to figure out what the direct and specific costs for this buildup of Lewy bodies is and research remains ongoing one thing they do know though is that these Lewy bodies can also be found in patients with Alzheimer's disease and Parkinson's disease suggesting that there might be some similarities and how the brain has trouble breaking down these types of proteins with that said patients with Parkinson's disease can develop dementia later on and if this happens we call it Parkinson's disease dementia and Parkinson's disease alone usually affects your motor control right with this type of dementia the Parkinson's disease has progressed to a point where it started affecting mental functions in addition to your motor functions now another type of dementia is frontotemporal dementia which used to be called picks disease and this type involves damage to the neurons that are specifically located in the frontal and temporal lobes of the brain and when these neurons are damaged things specific to those regions become affected right like spatial or Riaan in the frontal lobe or problems with speech from damage to the temporal lobe now dementia in general can also be caused or brought about by other factors that result in some kind of cumulative damage to your brain for example the toxic effects of alcohol and brain cells through alcohol misuse can damage brain tissue or repeated head injuries like those sustained by professional boxers or football players and we're talking both American football and soccer can seriously damaged brain tissue over time and it's also not uncommon for there to be more than one type of dementia present for example you could have Alzheimer's disease but also have vascular dementia as well