A severe injury to the head can throw victims into a coma if the neuronal discharge throughout the brain is severely disrupted.

"It’s like a massive power failure in a metropolis as a result of a natural disaster," said Professor Ivan Ng, senior consultant and head of the department of neurosurgery at the National Neuroscience Institute and the Singapore General Hospital.

Neurons are the cells that send and receive signals between the brain and nervous system. Without them, the body cannot function and the person remains unconscious.

As the swelling in the brain caused by the impact of the accident starts to go down, the neurons begin to regain their function and the patient wakes from the coma.

When Ruth regained her consciousness, she could not remember anything. She was also unable to recognise her husband and son.

Prof Ng said that this happens when the memory centres in the brain are damaged.

"In more extensive damage, the memory cells where long term memory is stored is destroyed leading to loss of long term memory," he added.

Ruth probably also suffered severe damage to the left hemisphere of the brain, which controls how she used language. She lost her ability to speak and had to relearn the different languages and dialects she used to know.

According to speech therapist Deirdre Tay from the department of speech therapy at the Singapore General Hospital, damage to different parts of the brain leads to different forms of language impairment.

Some may still have the ability to understand by hearing but not reading and others may have more difficulty speaking than writing.

Speech therapists use different approaches to help patients relearn names, grammar and form sentences.

"This helps the brain to reorganise and make new connections for the impaired language function," Ms Tay said, adding that sometimes patients learn to use another part of their brain that they don’t typically use for language.

When she began speaking again, Ruth’s friends imagined that she did so with an American accent. She watched CNN a lot and they thought she was imitating newsreaders’ accents. However Ms Tay gave another reason for this.

"Because of muscle weakness in the face, lips and tongue, patients have difficulty articulating their words, which may change their accent and make them sound a bit foreign," she said.

In addition to losing memory and speech, Ruth changed from being a friendly, sociable person to one who is afraid of strangers. This was due to the damage to the limbic system in the brain, leading to various personality changes, said Prof Ng. The limbic system supports the function of emotion, behaviour and long-term memory.

There are other factors. Psychologist Daniel Koh who conducts trauma counselling at Insights-tse, a private clinic, said a person may suffer from post-traumatic stress disorder (PTSD) after a bad accident. This includes a sense of helplessness, confusion, decreased self-esteem and excessive worrying, which may lead to anxiety or depression.

All this affects the person’s interaction with other people, which could lead to further withdrawal and self-distancing. The desire to avoid places which remind them of the accident also compounds the reclusion.

Emotional support from family and friends goes a long way in helping the patient recover from fear as well as memory loss. Gentle encouragement, motivation and just being there can help boost the person’s willpower to recover. However, he cautioned against being overly protective, which can make the patient too dependent.

"This will only add stress and put pressure on the patient, which may impede the recovery process, and even worsen the condition," he said.

Support groups such as the Singapore Brain and Spine Injury Foundation also bring together patients with head injuries and their family members to share their experiences at least once every two months.

Run by volunteer nurses, doctors and head injury survivors, the foundation conducts seminars and talks by psychologists and occupational therapists on how to manage their condition.

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