Types of brain disorders
Stroke - Fact Sheet
A Stroke is an interruption of blood supply to
part of the brain. Nutrients and oxygen are passed to each cell
through the arteries. If these become blocked, bleed or break then
the brain tissue that was being nourished deteriorates.
When this lack of blood supply occurs to the heart it is called
a heart attack. When it occurs in the brain it is called a stroke.
In fact, in America a stroke is called a "brain attack".
According to the Australian Institute of Health and Welfare
report Heart, stroke and vascular diseases, Australian facts 2004,
stroke is Australia's second biggest killer after heart attack, and
90% of Australian adults have at least one modifiable (i.e. can be
improved) risk factor. Although stroke is rarely immediately fatal,
the Stroke Foundation report that One in five people having a
first-ever stroke die within one month and one in three die within
a year. Australians will suffer around 60,000 new and recurrent
strokes (that's one stroke every 10 minutes).
Types of stroke
Obstruction of a blood vessel
A Blood Clot can cause a blockage in an artery. These clots can
occur in other parts of the body then break up and travel to the
brain where they lodge in the smaller blood vessels. A blood clot
that forms in a blood vessel or within the heart and remains there
is called a Thrombus. A thrombus that travels to another location
in the body is called an Embolus. The disorder is called an
Embolism. For example, an embolus that occurs in the brain is
called a Cerebral embolism.
Fatty lipids called plaques may build up on the walls of blood
vessels and restrict blood flow. As a result symptoms usually
develop slowly but may be rapid in some cases.
An aneurysm is a localised swelling of a blood vessel. This can
be caused by disease, congenital weakness of the blood vessel, or
injury. If an aneurysm does not burst it can become blocked,
leading to a stroke through obstruction. If it does not block, it
does not usually produce any symptoms and may not be detected. If
an aneurysm bursts, however, the result is a haemorrhage.
A haemorrhage is loss of blood from a blood vessel. In other
words, bleeding. There are two kinds of haemorrhage that can cause
a stroke. An intracerebral haemorrhage is caused by a ruptured
artery leaking blood directly into the brain. A subarachnoid
haemorrhage occurs on the surface of the brain and the blood fills
the space around the brain and creates pressure.
As well as starving regions of the brain of blood, the increased
pressure created by blood pooling inside or outside the brain can
impact the function of Neurons and lead to them slowly dying.
Effects of stroke
The after effects of a stroke vary widely for each stroke victim
as different parts of the brain are responsible for thought
processes, comprehension, movement and our senses. The extent of
blood shortage also determines the effect of the stroke.
A stroke in the left hemisphere of the brain may result
- Some degree of paralysis on the body's right side
- Loss of feeling on body's right side
- Right field of vision deterioration
- Loss of speech or comprehension (Aphasia), and other speech
problems including Echolalia (exact repetition of a word or
sentence just spoken by another person), perseveration (continual
repetition of a word or phrase), inappropriate use of "yes" and
"no" and inability to discriminate between left and right.
- Inability to name objects that can be recognised and used.
- Inappropriate laughing or crying.
- Easily becoming frustrated.
A stroke in the right hemisphere of the brain may result
- Some paralysis on the body's left side
- Lost or disturbed (hot or cold, acute or diminished pain)
feeling on body's left side
- Left field of vision deterioration - may only eat from right
hand side of plate.
- Poor judgement, Impulsivity or a lack of awareness of personal
- Short attention span or difficulty following instructions.
- Difficulty expressing emotions, or inappropriate emotions.
- Inability to read facial expressions or voice tone in other
- Difficulty speaking, slurred speech or incessant and repetitive
- Difficulty with simple addition, subtraction, multiplication,
division or a simple thought problem.
- Difficulty using money, dialling a telephone or recognizing the
time on a clock.
- Spatiotemporal difficulty with a tendency to get lost if left
alone or if out of one's Environment
Brain Stem and Cerebellum
Although the left and right hemispheres of the brain are usually
affected, damage in the lower levels of the brain can also occur.
The brain stem and cerebellum are involved in maintaining vital
body systems, reflexes and balance. A stroke in the brain stem can
- Inability to speak
- Unstable pulse
- Blood pressure fluctuations
- Difficulty swallowing or breathing
- Difficulty with eyeball movement.
A stroke in the cerebellum can cause:
- Double vision
- Dizziness and loss of balance
- Lack of coordination in the hands
- Slurred speech.
How to recognise a stroke
A stroke is not necessarily a major event, and may not be
recognisable as a stroke - it may only result in someone stumbling
or having a moment of blankness akin to an absent Seizure. It is
vital to treat a stroke immediately call an ambulance.
The FAST test is an easy way to recognise and remember the signs
of stroke. Using the FAST test involves asking three simple
- Face - Check their face. Has their mouth drooped?
- Arms - Can they lift both arms?
- Speech - Is their speech slurred? Do they understand you?
- Time - Time is critical. If you see any of these signs call an
ambulance straight away.
Surgery, drugs, acute hospital care and rehabilitation are all
accepted stroke treatments depending on the type of stroke.
An example of surgery is a carotid endarterectomy to remove
plaque if a neck artery is blocked. Aspirin is a common drug used
for thinning the blood. Other medications aim to dissolve clots
that lead to stroke. New techniques continue to arise, such as
cerebral angioplasty where balloons, stents and coils are used to
dilate small intracranial arteries and maintain blood flow.
Generally speaking the brain does not regenerate if brain tissue
dies after an embolism or thrombosis. After a haemorrhage the brain
may regain some function after the pressure caused by bleeding has
Recovery after a stroke depends on a number of factors
- The type and severity of the stroke
- The part of the brain involved
- The extent and nature of the damage
- Existing medical problems
- Type of treatment and rehabilitation.
Recovery usually involves a lot of relearning of activities such
as walking and talking. This Learning can be complicated by the
fact that many people have trouble concentrating after a stroke.
Research funded by the Stroke Association of Queensland found that
attention was affected markedly by a stroke in the front right side
of the brain. This part of the brain is responsible for attention
and concentration and a stroke here was found to lead to slower
rehabilitation as learning was impaired.
Rehabilitation aims to:
- Help you understand and adapt to your difficulties
- Regain skills
- Prevent secondary complications
- Help you and your family to come to terms with the stroke.
The team involved can be quite confusing for some patients. A
physiotherapist may be involved in assessing and assisting with
muscle strength, balance and mobility. An occupational therapist
helps with relearning practical tasks of everyday life such as
dressing, washing and using cutlery. A speech language pathologist
works not only with communication difficulties but also with
problems of swallowing. A social worker may assist with counselling
and advice about community support, financial issues and other
services. A Neuropsychologist may assist with Cognitive changes and
problems controlling emotions. The rehabilitation doctor's role is
to integrate medical requirements and treatments with the other
Knowledge of rehabilitation following a stroke is growing
steadily, as neurologists and neuropsychologists experiment with
using mirrors or offset treadmills to retrain muscle groups and
nerve pathways. As with any other form of brain injury, the key is
understanding, persistence and a close relationship with the
How can the family help?
The family can play a huge part in the rehabilitation process.
Ideally they should be included in some team meetings and sessions
so that they can carry on the learning process of their loved one.
Families can provide the emotional support that is crucial to
recovery and also keep the person in touch with the outside world.
Families also need to look after themselves and may benefit from
attending a support group for carers. A support group can also be
invaluable for their loved one.
Emotions following a stroke
A person who has had a stroke can experience a wide range of
emotions which are 'normal' reactions to an abnormal experience,
including, shock, anger, denial, Depression, Frustration, guilt and
grief. The shock of the stroke can combine with the effects of the
stroke upon the brain to cause unstable, or labile, emotions that
are socially inappropriate and which may harm the chances of
It is important to share these feelings and ask for help.
Reassurance that these feelings are to be expected can be a great
For more information, see the Fact Sheet Emotional Stages
References and further information