What is Dementia?

Dementia is the progressive deterioration in cognitive function – the ability to process thought (intelligence).


  • The causes of dementia include various diseases and infections, strokes, head injuries, drugs, and nutritional deficiencies. 
  • All dementias reflect dysfunction in the cerebral cortex, or brain tissue. Some disease processes damage the cortex directly; others disrupt subcortical areas that normally regulate the function of the cortex.
  • When the underlying process does not permanently damage the cortical tissue, the dementia may sometimes be stopped or reversed.
  • In classifying dementias, medical professionals may either separate cortical or subcortical dementias or divide reversible and irreversible dementias.


  • Memory loss – the patient may forget his way back home from the shops. He may forget names and places. He may find it hard to remember what happened earlier on during the day.
  • Moodiness – the patient may become more and more moody as parts of the brain that control emotion become damaged. Moods may also be affected by fear and anxiety – the patient is frightened about what is happening to him.
  • Communicative difficulties – the affected person finds it harder to talk read and/or write.