Brain injury - How the brain works

  • The brain is made up of different parts including the cerebrum, the cerebellum and the brain stem. The effects of a brain injury will depend on which part of the brain has been damaged, the severity of the injury and the age and stage of development of the child. 

    Parts of the brain

    Nerve cells in the brain send and receive electrical impulses to and from the body. If you take a close look at the human brain, you'll find it has three main parts.

    The largest is the cerebrum on top. The surface of the cerebrum is called the cerebral cortex. Although less than 0.5cm thick, the cerebral cortex is critical to your child's ability to move, to understand what they see and hear and to think - a complex process of making decisions, learning, remembering and planning.

    The cerebrum is divided into two halves called hemispheres. The corpus callosum is an 'electric highway' of nerve fibres which connects the two hemispheres and allows information to pass between. The hemispheres are divided into smaller parts: the frontal, temporal, parietal and occipital lobes.

    At the back of your brain and beneath the cerebral cortex is the cerebellum. The cerebellum coordinates skilled movement, giving your child the ability to walk without stumbling and to use their hands smoothly and precisely.

    Located at the base of the brain is the brain stem, a stalk-like structure that connects the brain to the spinal cord. The brain stem takes care of basic and involuntary functions such as breathing, blinking and bowel regulation.

    How the brain works RCH KHI

    Figure 1 The Brain Areas

    What are the effects of injury to the different areas of the brain?

    In focal brain injury, just one lobe in one hemisphere may be affected. In diffuse injury, all lobes of both hemispheres may be affected. There are connections between the different areas of the brain, and damage to one area may result in dysfunction associated with other parts of the brain.

    Frontal lobes

    The frontal system controls many complex functions, which are referred to as executive functions. These include planning, control of impulses, initiation, attention and emotion. The back of the frontal lobe also controls movement of the opposite side of the body. Damage to the frontal system (that is, damage to the frontal lobes directly or to the connections to the frontal lobe) may cause changes in behaviour, attention, emotions and also weakness to the opposite side of the body.

    Parietal lobes

    The parietal lobes provide sensory information to the brain including touch, pain and temperature. Damage may cause the child to lose sensation down the opposite side of the body. This may result in the child being less aware of parts of their body.  This is known as sensory neglect.

    Temporal lobes

    The functions of the temporal lobes include hearing, memory and learning. Damage may cause difficulties with organising what to say, and finding and using the correct words. It may also result in difficulties with short-term memory.

    Occipital lobes

    The occipital lobes help us understand what we see. They interpret the colour, shape and distance away of what we look at. Damage may result in a distortion of what is seen and difficulty recognising or interpreting familiar objects.


    Damage to this area may result in movement becoming jerky or uncoordinated and is known as cerebellar ataxia. The child's speech may also become slurred and difficult to understand. The cerebellum has rich connections to the cerebrum. Therefore, damage to the cerebellum can result in disruption to some of the functions controlled by other parts of the brain.

    Key points to remember

    • The central nervous system is made up of the brain, the brain stem, the cerebellum and spinal cord.
    • There are different areas of the brain including the frontal, parietal, temporal and occipital lobes.
    • The effects of brain injury will depend on what part of the brain, and/or which connections to an area within the brain are damaged.
    • Functions that are controlled by one part of the brain can be disrupted when connections to it are damaged due to brain injury.

    For more information

    Developed by The Royal Children's Hospital Paediatric Rehabilitation Service based on information from the Brain Injury Service at Westmead Children’s Hospital. We acknowledge the input of RCH consumers and carers.

    Reviewed September 2020.

    Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit


This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.