Around two thirds of people in Wales could be putting their lives at risk because they would not recognise the symptoms of TIAs, or mini strokes as they are known, which are caused by a temporay lack of blood to the brain.
They can be a sign that a person is about to suffer a major stroke with life threatening results .
But too few people in Wales are taking notice of the warning signs, as our health correspondent Mariclare Carey-Jones has been finding out.
Eleven thousand people a year in Wales suffer a stroke according to the Stroke Association.
Many of these strokes are classed as mini strokes, also known as Transient Ischaemic Attack (TIA).
The Stroke Association are keen that people recognise the symptoms of a mini stroke, which are no different to a full blown stroke, and treat it as a medical emergency.
The signs of a mini stroke are no different to signs of a full blown stroke and the only difference is the symptoms last for a shorter period.
Weakness down one side of the body
Pins and needles
Loss of speech or slurred speech
The Stroke Association urge people to treat signs of a stroke as a medical emergency and say figure show that one in ten people who suffer a mini stroke (TIA) that do not seek medical treatment will go on to have a full blown stroke.
Almost two thirds of people in Wales wouldn't recognise the symptoms of a mini stroke, warns the Stroke Association.
It also says eleven thousand people have a stroke every year in Wales
"The signs of a mini stroke are no different to the signs of a full-blown stroke" says the charity's spokesperson Ana Palazon.
"The difference is that they will only last for a few minutes - for example facial weakness, weakness on the side of the body, or pins and needles."