A answered. Atrial fibrillation can be caused by a number of different things that predispose the heart to arrhythmias. Most commonly, longstanding high blood pressure is the cause. Other causes include heart disease such as blockage in the coronary vessels or diseases such as pneumonia or COPD.
Definition: When an artist deliberately restricts the number of colors they use in a painting, they're said to be using a limited palette. (A palette being what paints are squeezed out onto, ready for use.). Also Known As: Restricted palette.
What is outsider art? It's a question that bedevils collectors and critics, who also worry about related terms such as folk art, self-taught art, vernacular art, naive art and primitive art -- words on which there is little consensus about appropriateness or even meaning. Roughly, though, a working definition of outsider art could go like this: