Progressive defective recognition of familiar people

This paper describes a right-handed patient (Maria), with a mild cognitive deterioration, who demonstrated the neuropsychological deficits of progressive bi-temporal atrophy. Temporal atrophy was ascertained by repeated MRI scanning. The patient was first assessed 5 1/2 years from clinical onset. The first 2 years were hallmarked by a worsening impairment of recognizing and identifying familiar people, which at our last assessment (13 months after the first) were very severe. Extra-facial information provided via conversation, gestures or clothes failed to counter the recognition defect. When given the names of the unrecognized familiar people, she had no difficulty retrieving the relevant biographical information. By contrast, hearing the name did not appear to help her to retrieve the corresponding visuo-perceptual characteristics. Two years post-onset, a milder, multisensorial defect of object recognition began to develop. During the last 6 months of observation, increasing lexico-semantic and aphasic defects became apparent. Psychometric assessment revealed that the patient's face recognition deficits were mainly 'associative'. Nevertheless, the patient was also impaired in some basic (i.e. 'apperceptive') visual skills. Her knowledge of colours and her spatial and reading skills were preserved. There were no signs of simultanagnosia. The patient's familiar people recognition defects were traced back to the malfunctioning of 'person identity nodes', and were considered to follow the more pronounced and earlier arising right temporal atrophy. The patient's multisensorial impaired recognition and naming of a still small number of common objects suggests the presence of semantic dementia arising from the concomitant less pronounced left temporal lobe atrophy. Clinically, this case may be viewed as an example of fronto-temporal dementia, consequent to a degenerative process of unknown histopathological nature.