Although the main causes are not specifically known, many researchers have found factors contributing to anomic aphasia. It is known that people with damage to the left hemisphere of the brain are more likely to have anomic aphasia. Broca's area, the speech production center in the brain, was linked to being the source for speech execution problems, with the use of functional magnetic resonance imaging (fMRI), now commonly used to study anomic patients.[8] Other experts believe that damage to Wernicke's area, which is the speech comprehension area of the brain, is connected to anomia because the patients cannot comprehend the words that they are hearing.[9]