A Twenty-Year Follow-up Case Study of an Office Worker Who Returned to Work despite Serious Memory Disorder Caused by Herpes Encephalitis

摘要

This study followed a 52-year-old male patient, who had suffered from severe impairment in recent memory due to se- quelae of herpes encephalitis, for 20 years. He returned to his highly intellectual work and performed well despite his doctor’s prediction. While the patient showed consistently poor results on various neuropsychological memory tests, he demonstrated incredible performance at work. This case exemplifies an extreme case that declarative memory is formed with the support of semantic memory, procedural memory, and his strong interests. Additionally, it offers lessons that results on memory tests do not necessarily correspond to the actual level of competence. The focal sites were found on both sides of the medial temporal lobe, predominantly on the left side. The T2-weighted magnetic resonance images (MRI) obtained 9 years after the onset confirmed widespread damage to the left brain including parahippocampal gyrus, hippocampus, spindle gyrus, and amygdaloid complex, with microlesions extending from the right parahippocampal gyrus to its antero-interior rim. However, the damage to hippocampus was presumed to be minor.