Types of brain disorders
Introduction to brain disorders
Almost everything we do, say and think is
controlled by our brain, so when our brain is injured it has the
potential to affect every aspect of life.
Brain disorders are often called the hidden disability because
there can be serious problems with our behaviour and ability to
think, and yet there is often no visible physical change with many
brain disorders - so problems can be easily ignored or
misunderstood. Even a traumatic brain injury may leave no visible
scars to indicate an injury too, place.
Sometimes a person will find even their family members see them
as being lazy or hard to get along with, when these are caused by
the brain disorder itself.
Over two million Australians are affected with some form of
brain disorder - that's over one in 12 according to statistics from
the World Health Organization.
WHAT IS A BRAIN DISORDER?
A brain disorder is not an intellectual disability. Intelligence
is usually not affected, although there are usually cognitive
changes such as problems with memory, concentration and attention.
It is also not a mental illness, although it can increase the
chances of mental disorders such as depression and anxiety.
A brain disorder occurs when there is damage or disruption to
the brain after birth, such as:
- Falls, accidents, assault,
concussion and other trauma
- Stroke and other vascular
- lack of oxygen (e.g. near
- Alzheimer's disease and
- Degenerative diseases
(e.g. dementia, Parkinson's disease)
- Parkinson's disease
- Alcohol and other
- Brain tumours
- Infections and diseases
A brain disorder can affect anyone, but unfortunately it is
often the most vulnerable people in the community affected, such as
Indigenous Australians, homeless people and survivors of domestic
EFFECTS OF A BRAIN DISORDER
Long-term effects will be different for each person, and will
also vary depending on the type of brain disorder. For example,
disorders such as Parkinson's disease and multiple sclerosis will
leave our cognition (e.g. our ability to think) intact, but have
dramatic impacts on the body's ability to control movement.
Other disorders will result in more cognitive effects such
- Fatigue and poor concentration
- Lack of initiative and motivation
- Irritability, anger and easily stressed
- Inappropriate behaviour
- Self-centredness, dependency and lack of insight
- Slowed responses and poor social skills
- Poor problem-solving
- Depression and lack of emotional control
- Impulsive behaviour.
Physical effects can vary widely between the disorders, with
some of the more common ones including:
- Movement disorders and paralysis
- Loss of taste and smell
- Dizziness and balance problems
- Epilepsy and seizures
- Eyesight and hearing problems
- Chronic pain.
TYPES OF BRAIN DISORDER
Traumatic Brain Injury
Traumatic brain injury (TBI) is caused by either a blow to the
head or by the head being forced to move rapidly forward or
backward. Brain tissue may be torn, stretched, penetrated, bruised
or become swollen. Oxygen may not be able to get through to the
brain cells and there may be bleeding.
Common causes include motor vehicle accidents, assault, falls,
sport accidents, domestic violence, and young babies being shaken.
Its effects can be temporary or permanent, and range from mild
injury, such as being momentarily stunned while playing football,
to a very severe injury that may cause prolonged loss of
Apart from the injury to the brain caused by the initial trauma,
there are secondary effects that can arise from bleeding, bruising,
lack of oxygen and increased pressure within the skull.
Hypoxic injury (lack of oxygen)
Common causes of hypoxia include near drowning and failed
suicide attempts such as hanging or carbon monoxide poisoning. This
usually leads to a diffuse brain injury, in that large areas of the
brain are affected instead of very specific areas.
Brain tumours can restrict blood supply to other cells or may,
through exerting physical pressure upon cells, squash them.
Infectious substances may cause cell death through exerting
pressure if the brain swells (encephalitis) or the tissue
surrounding the brain swells (meningitis), or may kill cells
through direct infection. Viral infections may result in diffuse
injury which can manifest as fatigue disorders such as chronic
There are several mechanisms which may be at work with
degenerative conditions, with the more commonly known ones
including multiple sclerosis, Parkinson's disease and Alzheimer's
In multiple sclerosis, nerve cells die when the
myelin is removed - myelin is a fatty coating that acts in a
similar way to the plastic insulation on electrical wiring. The
exact cause is unknown, and there is no cure although treatments
exist that can reduce the symptoms.
Parkinson's disease results from the loss of
cells in various parts of the brain, including an area that creates
dopamine. Loss of dopamine causes neurons to fire without normal
control, leaving people less able to direct or control their
movement. The exact cause of Parkinson's disease is unknown, and
the single biggest risk factor is advancing age. The effects
include slowness of movement, rigidity, tremors and balance
Alzheimer's disease accounts for roughly two in
three cases of dementia. The causes are poorly understood, but
genes play a major role, and there is no cure. Plaques and
tangles in the brain usually develop later in life and lead to
problems with short-term memory, disorientation, mood swings and
behavioural issues. The average life expectancy is three to nine
years after diagnosis.
Stroke & other vascular diseases
A stroke occurs when blood supply within the brain is disrupted.
Arteries with the brain are either blocked, broken or begin
bleeding which prevents oxygen and nutrients getting to the brain
cells. When this lack of blood supply occurs to the heart it is
called a heart attack - in the brain it is called a stroke. The
effects vary widely 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
Infections can injure the brain and even lead to death very
quickly, so urgent medical attention is always critical.
Meningitis is an inflammation of the protective
membranes that cover the brain and spinal cord, which leads to high
fever, headaches, sensitivity to light, confusion, and occasionally
seizures. Vaccination of young children is strongly recommended as
a preventative measure. The most common causes of meningitis are
viruses, bacteria, fungi, and protozoa.
Encephalitis is a swelling of the brain
caused by viruses or bacteria. This can occur through insect bites,
contaminated food, or other existing infections and diseases.
Symptoms include an unsteady walk, sleepiness, confusion, fever,
headache, light sensitivity, seizures, paralysis and impaired
Epilepsy involves recurring brief episodes of abnormal
electrical activity in the brain leading to uncontrolled
convulsions and unconsciousness, or just a momentary loss of
awareness. The exact cause is unknown, but the majority of
recurring seizures can be prevented by medications. While epilepsy
is a brain disorder itself, it can also be caused by other
disorders such as a Traumatic brain Injury.