The individual will show mild signs of the disease such as memory lapses where the person affected will forget names, recent events, familiar words and the location of everyday objects such as pens, wrist watches and keys for example. This stage of Alzheimer's isn't usually detected during a medical examination and by friends and loved ones, or indeed the person affected by these 'changes'.

Alzheimer's Stage 3: Mild cognitive decline

This is the stage where some individuals (but not all) can be diagnosed with Alzheimer's as certain symptoms become telling to others such as family and friends or work colleagues for example.

Symptoms to look out for:

Word or name finding problems.

Inability to remember the names of people when introduced to these new people.

Inability to remember passages of text the individual has recently read.

Inability to plan and organize functionally.

Inability to perform in social or work environments to usual standards.

Misplacing a valuable object or item and forgetting where that object is.

Inability to write coherently with unusual words appearing throughout.

Alzheimer's Stage 4: Moderate cognitive decline

This is the stage where under careful medical examination, the individual shows clear deficiencies or signs of deterioration in some or all of the following:

Impaired memory of recent occasions or current events.

Impaired ability to perform abstract mental tasks such as counting backwards from 100 in 7s.

Impaired ability to perform tasks that require planning such as a meal or managing finances.

Decreased memory of personal experiences or history.

A subdued or withdrawn state of mind in social or mentally challenging situations.

Alzheimer's Stage 5: Moderately severe cognitive decline

This is the stage where individuals start to show major gaps in memory function and a decline in cognitive thinking. At this stage everyday assistance is often essential to the individual.

Symptoms to look out for:

Inability to recall personal address, date of birth, their own telephone number or where they went to school or college.

Inability to determine time, date of day, what week or year it is and even what season the calendar is in such as summer or winter for example.

Impaired ability to perform less challenging abstract tasks such as counting backwards from 20 in 2s.

Require assistance in choosing correct clothing for the calendar season such as summer or winter. Often sufferers will choose winter clothing for the summer and vice versa for the winter.

Can recall their own name, names of children or loved ones with a high degree of knowledge.

Don't require assistance when eating or using the toilet for example.

Alzheimer's Stage 6: Severe cognitive decline

This is the stage where impaired memory function begins to worsen further, affecting the individual's personality and again, sufferers will require extensive daily care.

Symptoms to look out for:

A loss of awareness of recent events, experiences and surroundings.

Impaired ability to recollect personal history although most can generally remember their own name.

Impaired ability to remember their spouse's name or caregiver, although most can generally recognize familiar faces from non-familiar faces.

Require assistance in getting dressed. Some sufferers will for example, put their shoes on the wrong feet or wear their pajamas over their clothing.

Experience disruption to sleep/walking cycles. Some sufferers will wander in the night and become lost, even in their own homes.

Require assistance in using the toilet.

Suffers increasing episodes of urinary or fecal incontinence.

Experiences personality and behavioral changes such as paranoia, delusions, hallucinations and compulsive or repetitive behavior like tissue shredding for example.

Alzheimer's Stage 7: Very severe cognitive decline

This is the final stage of Alzheimer's where the individual concerned will lose the ability to speak, respond to their environment and lose the ability to control body movement.

Symptoms to look out for:

Frequent inability to recognize speech and therefore talking becomes impaired.

Assistance required for eating and using the toile and frequent incontinence issues.

Inability to walk or sit without assistance or support, to smile and to support their own head. Movement also becomes rigid as muscles seize and reflexes slow and swallowing becomes impaired too.