[Outcome of "well-differentiated jargon" and related lesions].

We introduce "well-differentiated jargon" as a new type of jargon with two relevant cases. To give a simple and clear framework to a classification of jargon, we define three types of jargon as follows: Under the condition that utterance does not decrease remarkably, (1) If approximately 90% of whole utterance consists of real words and clear syntactic structure though incomprehensible, it is "well-differentiated jargon". (2) If approximately 90% of whole utterance consists of unclear phonemes or phonemes that are not able to divide into words, it is "undifferentiated jargon". (3) If in-comprehensible utterance does not belong to any type of jargon above, it is "moderately-differentiated jargon". In this line of definition, "well-differentiated jargon" is the most highly differentiated jargon. The following cases are the examples of "well-differentiated jargon": Case 1 was a 67-year-old woman with head injury of the left orbital cortex, prefrontal cortex, and temporal pole; Case 2 was a 64-year-old man with brain atrophy in bilateral frontal cortex and bilateral (right dominant) anteroinferior temporal cortex after meningoencephalitis. Within six months after onset, they showed characteristic verbal aspects as follows; transcortical sensory aphasia; utterance with a lot of perseverative error, irrelevant words, unnecessary qualifiers during the naming task; well-preserved syntactic structure in a sentence with a few neologism. One year after the first verbal assessment, the performance of Case 1 improved almost entirely, whereas characteristic utterance was still observed in Case 2. These results suggest that "well-differentiated jargon" can be caused by lesions in anteroinferior temporal cortex and prefrontal cortex with preserved language area, where involve more anterior region than that of classical jargon. These two cases cannot belong to any classical jargon, and then we insist the adoption of new type of jargon, "well-differentiated jargon".