Alzheimer's disease is a progressive brain disorder that destroys memory and thinking skills. It accounts for 60-80% of dementia cases and usually starts slowly and gets worse over time, becoming severe enough to interfere with daily life. The main risk factor is age, though genetic and lifestyle factors may also play a role. Symptoms include memory loss and difficulties with problem-solving, planning, and language. Currently, there is no cure, but treatments can help with cognitive and behavioral symptoms.

1. Alzheimer’s :
a general term for memory loss and other intellectual abilities serious enough to
interfere with daily life. Alzheimer's disease accounts for 60 to 80 percent of
dementia cases.
lzheimer Type (SDAT) terminal diseasealso known as Senile Dementia of the A
was first described by a German psychiatrist and neuropathologist Alois
Alzheimer in 1906 and was named after him.
Many scientists believe that Alzheimer's disease results from an increase in the
production or accumulation of a specific protein (beta-amyloid protein) in the
brain that leads to nerve cell death.
, although the greatest known risk factorAlzheimer's is not a normal part of aging
and older.is increasing age, and the majority of people with Alzheimer's are 65
But Alzheimer's is not just a disease of old age. Up to 5 percent of people with
onset), which-the disease have early onset Alzheimer's (also known as younger
often appears when someone is in their 40s or 50s.
Symptoms of Alzheimer's:
Just like the rest of our bodies, our brains change as we age . Most of us
eventually notice some slowed thinking and occasional problems with
remembering certain things. However, serious memory loss, confusion and other
major changes in the way our minds work may be a sign that brain cells are
failing.
The most common early symptom of Alzheimer's is difficulty remembering
newly learned information because Alzheimer's changes typically begin in the
part of the brain that affects learning. As Alzheimer's advances through the brain
it leads to increasingly severe symptoms, including disorientation, mood and
behavior changes; deepening confusion about events, time and place; unfounded
suspicions about family, friends and professional caregivers; more serious
memory loss and behavior changes; and difficulty speaking, swallowing and
walking
Causes of Alzheimer’s Disease:
Scientists don’t yet fully understand what causes AD, but it is clear that it
develops because of a complex series of events that take place in the brain

2. over a long period of time. It is likely that the causes include genetic,
environmental, and lifestyle factors.
Some drug therapies propose that AD is caused by reduced synthesis of the
neurotransmitter acetylcholine.
Other cholinergic effects have also been proposed, for example, initiation
of large-scale aggregation of amyloid leading to generalized
neuroinflammation.
Alzheimer's disease is characterized by a build-up of proteins in the brain.
Though this cannot be measured in a living person, extensive autopsy
studies have revealed this phenomenon. The build-up manifests in two
ways:
Plaques– deposits of the protein beta-amyloid that accumulate in the spaces
between nerve cells
Tangles – deposits of the protein tau that accumulate inside of nerve cells
Risk factors :
Some things are more commonly associated with Alzheimer's disease - not seen
so often in people without the disorder. These factors may therefore have some
direct connection. Some are preventable or modifiable factors (for example,
ofmay in turn cut the riskdiseaseheartordiabetesreducing the risk of
dementia).
If researchers gain more understanding of the risk factors, or scientifically prove
any "cause" relationships for Alzheimer's, this could help to find ways to prevent
it or develop treatments.
How Alzheimer effect on brain :
In Alzheimer's disease, there is an overall shrinkage of brain tissue. The
grooves or furrows in the brain, called sulci (plural of sulcus), are noticeably
widened and there is shrinkage of the gyri (plural of gyrus), the well-
developed folds of the brain's outer layer. In addition,the ventricles, or
chambers within the brain that contain cerebrospinal fluid, are noticeably
enlarged. In the early stages of Alzheimer's disease, short-term memory
begins to fade (see box labeled 'memory') when the cells in the hippocampus,
which is part of the limbic system, degenerate.
Ths brain :

3. The brain is made of three main parts: the forebrain, midbrain, and hindbrain.
The forebrain consists of the cerebrum, thalamus, and hypothalamus (part of
the limbic system). The midbrain consists of the tectum and tegmentum. The
hindbrain is made of the cerebellum, pons and medulla. Often the midbrain,
pons, and medulla are referred to together as the brainstem.
Treatment :
Currently, there is no cure for Alzheimer's. But drug and non-drug treatments
may help with both cognitive and behavioral symptoms.
Researchers are looking for new treatments to alter the course of the disease and
improve the quality of life for people with dementia.