Prosopagnosia, Other Specific Cognitive Deficits, and Behavioral Symptoms: Comparison between Right Temporal and Behavioral Variant of Frontotemporal Dementia

Abstract

Right temporal variant of frontotemporal dementia (rtv-FTD) represents an uncommon and recently described frontotemporal dementia (FTD) entity presenting with symptoms in many ways comparable to those of the frontal or behavioral variant of FTD (bv-FTD). The aims of this study were to explore the timing of cognitive and behavioral symptoms of rtv-FTD, and to compare the distinct cognitive deficits including prosopagnosia and behavioral symptoms of rtv-FTD patients with those observed in bv-FTD patients. We reviewed the records of 105 patients clinically diagnosed with FTD. A total of 7 patients (5 men/2 women) with FTD and marked right temporal atrophy in magnetic resonance imaging (MRI) were detected. Clinical features were compared with those observed in a group of 22 age-matched patients (16 men/6 women) with FTD and predominant frontal lobe atrophy. The main presenting symptoms of rtv-FTD were prosopagnosia, apathy, and episodic memory impairment. In contrast, social awkwardness and compulsive behaviors were dominant in later stages of the disease together with disinhibition and loss of insight with a marked personality change. Although the cognitive and behavioral profiles of patients with right temporal or frontal lobes atrophy present substantial similarities, each subtype has a number of distinct characteristics. It appears that prosopagnosia, obsessive behaviors, and psychotic symptoms are more prominent in rtv-FTD patients.

Clinical and neuroanatomical characterization of the semantic behavioral variant of frontotemporal dementia in a multicenter Italian cohort

“…Furthermore, prosopagnosia was not consistently tested in the bvFTD and svPPA groups, possibly limiting its detection [ 25 ]. Previous studies have reported prosopagnosia in both bvFTD and svPPA cases, but at consistently reduced rates compared to what we have observed in our sbvFTD cohort [ 36 , 37 ].…”

Hemispheric asymmetries in hippocampal volume related to memory in left and right temporal variants of frontotemporal degeneration

“…Deficits in socioemotional functioning are prominent ( 6 , 11 ), as are difficulties with visual object recognition ( 20 ). In particular, inability to recognize faces (prosopagnosia) is a frequently reported symptom in rtvFTD ( 19 , 21 – 25 ). There are fewer studies of rtvFTD compared to svPPA, but in one report Chan and colleagues ( 17 ) found that anterior temporal atrophy in rtvFTD extended to the hippocampus, resulting in greater volume loss in the right hemisphere.…”