Boots WebMD Partners in Health
Return To Boots

Picture of the brain

Picture of Human Brain

The brain is one of the largest and most complex organs in the human body. It is made up of more than 100 billion nerves that communicate in trillions of connections called synapses.

The brain is made up of many specialised areas that work together.

  • The cortex is the outermost layer of brain cells. Thinking and voluntary movements begin in the cortex.
  • The brain stem is located between the spinal cord and the rest of the brain. Basic functions such as breathing and sleep are controlled here.
  • The basal ganglia are a cluster of structures in the centre of the brain. The basal ganglia coordinate messages between multiple other brain areas.
  • The cerebellum is at the base and the back of the brain. The cerebellum is responsible for coordination and balance.

    The brain is also divided into several lobes.
  • The frontal lobes are responsible for problem solving and judgment and motor function.
  • The parietal lobes manage sensation, handwriting and body position.
  • The temporal lobes are involved with memory and hearing.
  • The occipital lobes contain the brain's visual processing system.

The brain is surrounded by a layer of tissue called the meninges. The skull (cranium) helps protect the brain from injury.

Brain conditions

  • Headache. There are many types of headaches; some can be serious but most are not and are generally treated with analgesics/ painkillers.
  • Stroke (brain infarction). Blood flow and oxygen are suddenly interrupted to an area of brain tissue, which then dies. A blood clot or bleeding in the brain are the cause of most strokes.
  • Brain aneurysm. An artery in the brain develops a weak area that swells, balloon-like. A brain aneurysm rupture can cause a stroke.
  • Subdural haematoma. Bleeding within or under the dura, the lining inside of the skull. A subdural haematoma may exert pressure on the brain, causing neurological problems.
  • Epidural (Extradural) haematoma. Bleeding between the tough tissue (dura) lining the inside of the skull and the skull itself, usually shortly after a head injury. Initial mild symptoms can progress rapidly to unconsciousness and death if untreated.
  • Intracerebral haemorrhage. Any bleeding inside the brain.
  • Concussion. A brain injury that causes a temporary disturbance in brain function. Traumatic head injuries cause the most concussions.
  • Cerebral oedema. Swelling of the brain tissue in response to injury or electrolyte imbalances.
  • Brain tumour. Any abnormal tissue growth inside the brain. Whether malignant ( cancer) or benign, brain tumours usually cause problems by the pressure they exert on the normal brain.
  • Glioblastoma. An aggressive, malignant brain tumour ( cancer). Brain glioblastomas progress rapidly and are very difficult to cure.
  • Hydrocephalus. An abnormally increased amount of cerebrospinal (brain) fluid inside the skull. Usually this is because the fluid is not circulating properly.
  • Normal pressure hydrocephalus. A form of hydrocephalus that often causes problems walking, along with dementia and urinary incontinence. Pressures inside the brain remain normal, despite the increased fluid.
  • Meningitis. Inflammation of the lining around the brain or spinal cord, usually from infection. Stiff neck, neck pain, headache, fever and sleepiness are common symptoms.
  • Encephalitis. Inflammation of the brain tissue, usually from infection. Fever, headache and confusion are common symptoms.
  • Traumatic brain injury. Permanent brain damage from a traumatic head injury. Obvious mental impairment or more subtle personality and mood changes can occur.
  • Parkinson’s disease. Nerves in a central area of the brain degenerate slowly, causing problems with movement and coordination. A tremor of the hands is a common early sign.
  • Huntington’s disease. An inherited nerve disorder that affects the brain. Dementia and difficulty controlling movements (chorea) are its symptoms.
  • Epilepsy. The tendency to have seizures. Head injuries and strokes may cause epilepsy, but usually no cause is identified.
  • Dementia. A decline in cognitive function resulting from death or malfunction of nerve cells in the brain. Conditions in which nerves in the brain degenerate, as well as alcohol abuse and strokes, can cause dementia.
  • Alzheimer’s disease. For unclear reasons nerves in certain brain areas degenerate, causing progressive dementia. Alzheimer’s disease is the most common form of dementia.
  • Brain abscess. A pocket of infection in the brain, usually caused by bacteria. Antibiotics and surgical drainage of the area are often necessary.


WebMD Medical Reference

Popular slideshows & tools on BootsWebMD

How to help headache pain
rash on skin
Top eczema triggers to avoid
Causes of fatigue & how to fight it
Tips to support digestive health
woman looking at pregnancy test
Is your body ready for pregnancy?
woman sleeping
Sleep better tonight
Treating your child's cold or fever
fifth disease
Illnesses every parent should know
spoonfull of sugar
Surprising things that harm your liver
woman holding stomach
Understand this common condition
What your nails say about your health