The brain region called the hippocampus is the center of learning and memory in the brain, and the brain cells in this region are often the first to be damaged. That's why memory loss is often one of the earliest symptoms of Alzheimer's.
Dementia is caused by damage to or loss of nerve cells and their connections in the brain. Depending on the area of the brain that's damaged, dementia can affect people differently and cause different symptoms.
With Alzheimer's disease, memory-related areas in the lower and back parts of the brain tend to be affected first. Other types of dementia can affect regions that control movement. “The treatment for all of these disorders is slightly different,” Miller says. That's why it's important to get an accurate diagnosis.
At first, Alzheimer's disease typically destroys neurons and their connections in parts of the brain involved in memory, including the entorhinal cortex and hippocampus. It later affects areas in the cerebral cortex responsible for language, reasoning, and social behavior.
In Alzheimer's disease, clumps of a protein called amyloid form around nerve cells in the brain. Amyloid also builds up inside the walls of brain blood vessels. This amyloid damages blood vessels and may interfere with blood flow in the brain.
Besides the typical cognitive decline, patients with Alzheimer's disease (AD) develop disorders of the respiratory system, such as sleep apnea, shortness of breath, and arrhythmias. These symptoms are aggravated with the progression of the disease.
Two of the most alarming physical symptoms associated with dementia are muscle weakness and in severe cases, paralysis – both of which can become an unpleasant reality for people in the mid to late stages of the illness.
The incidence of acute organ dysfunction (≥1 system) was approximately twice higher in patients with dementia than in control subjects (Table 2).
Peripheral Sensory Nerve Conduction and Cognitive Function
A clinical study found a lower degree and frequency of pain in patients with AD than in cognitively healthy elderly,42 suggesting that there may be changes in peripheral nerve sensory function in patients with AD.
Functions that are particularly affected in dementia include executive function (the ability to plan, organise and complete tasks), vision, language, emotion and behaviour, and memory.
Alzheimer's disease accounts for 60-80% of cases. Vascular dementia, which occurs because of microscopic bleeding and blood vessel blockage in the brain, is the second most common cause of dementia. Those who experience the brain changes of multiple types of dementia simultaneously have mixed dementia.
For most people with Alzheimer's — those who have the late-onset variety — symptoms first appear in their mid-60s or later. When the disease develops before age 65, it's considered early-onset Alzheimer's, which can begin as early as a person's 30s, although this is rare.
The hippocampus is affected by Alzheimer's disease.
The damaged nerve cells in the hippocampus mean this part of the brain can't function properly, which can lead to the early symptoms of Alzheimer's – memory loss and disorientation. The temporal lobe is affected by frontotemporal dementia, a rare type of dementia.
New researches indicate that gastrointestinal tract microbiota are directly linked to dementia pathogenesis through triggering metabolic diseases and low-grade inflammation progress.
What is Alzheimer disease? Alzheimer disease is a disease that affects the brain and nervous system. It happens when nerve cells in the brain die. The disease gets worse over time.
The immune cell balance changes were informative, suggesting that dementia was exacerbating the normal age-related changes in the immune balance – more innate granulocytes and fewer adaptive immune cells.
There are different personal risk factors that cause people to fall, however, people with dementia are at greater risk because they: are more likely to experience problems with mobility, balance and muscle weakness.
Bone health is an important issue in AD given a higher risk of falls and increased incidence of fractures in individuals with AD compared to cognitively healthy older adults. Additionally, individuals with AD have poorer recovery[6–8] and higher mortality rates[9] after suffering a hip fracture.
As Alzheimer's disease progresses to its last stages, brain changes begin to affect physical functions, such as swallowing, balance, and bowel and bladder control. These effects can increase vulnerability to additional health problems such as: Inhaling food or liquid into the lungs (aspiration)
Data from a 10-year follow-up study showed declining kidney function is significantly associated with dementia risk among older adults.
Amyloid protein made in the liver can cause neurodegeneration in the brain, according to a new study. Since the protein is thought to be a key contributor to development of Alzheimer's disease (AD), the results suggest that the liver may play an important role in the onset or progression of the disease.
A series of experiments presented today (Wednesday 2 March) at the Alzheimer's Research UK 2022 Conference at the Brighton Centre, has implicated the health of the gut in the development of Alzheimer's disease.
Low gait speed was also found in the early stage of AD and progressed with advancing dementia. Our results suggest that decreased muscle strength without loss of muscle mass in the upper or lower extremities and low gait speed are early non-cognitive features of elderly patients with AD.
The progression of dementia, which impairs motor skills and cognitive function, is a warning of greater disability. The present study investigated the association between hand fine motor skills, assessed according to the Functioning Disability Evaluation Scale - Adult Version (FUNDES-Adult), and dementia severity.
When your loved one with Alzheimer's disease has breathing problems, they feel like they have to work harder than usual to get air. They might also feel like they can't take a deep breath or get enough air. The problem can start suddenly or come on slowly over weeks or months.