A transient ischemic attack (TIA) is sometimes called a mini-stroke. TIAs may last just a few minutes when a clot or other blockage temporarily decreases blood flow to your brain. Symptoms may occur only briefly during the TIA. A TIA is a warning that a stroke may happen soon. Getting early treatment for a TIA can help prevent a stroke. If several smaller strokes occur over time, you may have more gradual changes in walking, balance, thinking, or behavior. Doctors call these changes multi-infarct dementia.