In contrast to pure mutism, they show frustration when unable to speak. Acute lesion of supplementary motor or Broca's areas of the frontal lobe produce this syndrome. This refers to a specific deficit of perception of spoken language. Other auditory perception is intact. Speech is intact but some garbled language may be present at the onset of illness.
Writing is normal.
Reading may be impaired. Lesion of the primary auditory cortex contiguous to Wernicke's area produces this syndrome. This disorder involves a disconnection of the language centers from visual perceptual areas. The patient cannot read but other language functions are intact. The patient must have a lesion of the left occipital lobe that also includes the pathways connecting the visual perceptual areas.