Neuroplasticity – The Brain's Repairing Mechanism

 Injuries to the head can result in long term damage to areas of the brain, varying depending on where on the head the injury was sustained. While a variety of therapeutic services can be employed to regain a certain level of functionality the brain also has a unique response to regional damage – neuroplasticity.

Neuroplasticity is the brain's ability to reorganize itself through lifetime creation of new neuron pathways. From birth developmental plasticity begins, as neuron branches and synapses form to process new sensory information. At the age of two or three, a child's brain has around 15,000 synapses per neuron. This is around twice as many as in the adult brain as neurons strengthen, weaken, and are eliminated with age. While this process slows down, the brain retains the ability to grow new neurons throughout life in response to new stimuli. One such circumstance under which the brain may begin to regenerate in this way is when a certain area of it is damaged.

Known as functional plasticity, in response to an area of the brain loosing functionality, often the surrounding healthy areas will take over those processes, restoring former abilities. Neurons which remain undamaged will grow new nerve endings to create new connections where the original links were broken due to injury. As well as restoring connections, undamaged neuron axons can create entirely new pathways, developing nerve endings that connect with other undamaged neurons, to carry out necessary functions. Especially in children, when damage is sustained in one hemisphere of the brain, the corresponding area in the other half of the brain may take on functions traditionally performed in the initial hemisphere.

One example of when natural adult neurogenesis (formation of new neuron endings) can occur is following a stroke. Strokes are caused either when a blood clot prevents sufficient oxygen flow to the brain or when a blood vessel bursts leading to internal bleeding in the head. If left untreated, a stroke can cause certain areas of the brain to cease to function. Strokes can cause long-lasting physical and psychological problems, however, the brain may attempt to compensate for permanent localized damage by re-routing function pathways.

Head injuries can cause debilitating damage that leave the patient with reduced functionality. Therapeutic rehabilitation, such as physiotherapy, occupational therapy, and speech therapy can go some way to recovering a patient's abilities, however, the body's natural propensity to repair itself, many also contribute to patient recovery following a localized head injury.