Social Cognition Deficits Are Pervasive across Both Classical and Overlap Frontotemporal Dementia Syndromes

Abstract

<b><i>Objectives:</i></b> Frontotemporal dementia (FTD) syndromes are a complex group of disorders characterised by profound changes in behaviour and cognition. Many of the observed behavioural abnormalities are now recognised to be due to impaired social cognition. While deficits in emotion recognition and empathy are well-recognised in behavioural-variant (Bv)FTD, limited information exists about the nature of social cognitive impairment in the language variant primary progressive aphasia (PPA) that includes progressive non-fluent aphasia (PNFA) and semantic dementia (SD), and in the motor variants FTD amyotrophic lateral sclerosis (FTD-ALS) and FTD progressive supranuclear palsy (FTD-PSP). This prospective study sought to explore the nature and profile of social cognition deficits across the spectrum of FTD. <b><i>Methods:</i></b> Sixty patients on the FTD spectrum, i.e., classical (16 with BvFTD and 20 with PPA) and overlap FTD syndromes (13 with FTD-ALS and 11 with FTD-PSP) were evaluated by means of the social cognition tasks, the Interpersonal Reactivity Index (IRI) for empathy, and pictures of facial affect (POFA) for emotion recognition. General cognition and behaviour were also assessed. <b><i>Results:</i></b> A significant impairment in emotion recognition and empathy was detected in both the classical and overlap FTD syndromes. The recognition of positive emotions was relatively preserved compared to that of negative emotions. Among the FTD subtypes, maximal impairment of empathy was demonstrated in FTD-PSP. <b><i>Conclusion:</i></b> Social cognition impairment is pervasive across the spectrum of FTD disorders, and tests of emotion recognition and empathy are clinically useful to identify the nature of behavioural problems in both classical and overlap FTD. Our findings also have implications for understanding the neural basis of social cognition in FTD.

The contribution of behavioral features to caregiver burden in FTLD spectrum disorders

“…The association of apathy and disinhibition to caregiver burden is consistent with the past literature 3,8,12 . Both are common across FTLD spectrum disorders 12,14,52 . Apathy is most prevalent, 12,53 characterized by a lack of motivation and interest in activities, and often occurs alongside emotional withdrawal 53 .…”

“…3,8,12 Both are common across FTLD spectrum disorders. 12,14,52 Apathy is most prevalent, 12,53 characterized by a lack of motivation and interest in activities, and often occurs alongside emotional withdrawal. 53 Apathy can be uniquely distressing to family members who feel that patients are no longer themselves 8,53 and may be particularly challenging in adults who retain job and family responsibilities.…”

Impaired recognition of disgust in amyotrophic lateral sclerosis is related to basal ganglia involvement

“…Changes in emotional processing in ALS have been described in an early report by Lulè and colleagues (Lule et al, 2005), who demonstrated that patients judged socio-emotional stimuli as more positive than controls and exhibited reduced subjective arousal. Caregivers of ALS patients meeting also criteria for FTD described a significant reduction of their empathic concern and perspective-taking abilities after disease onset (Arshad et al, 2020).…”

Impaired recognition of disgust in amyotrophic lateral sclerosis is related to basal ganglia involvement

“…Changes in emotional processing in ALS have been described in an early report by Lulè and colleagues ( Lule et al, 2005 ), who demonstrated that patients judged socio-emotional stimuli as more positive than controls and exhibited reduced subjective arousal. Caregivers of ALS patients meeting also criteria for FTD described a significant reduction of their empathic concern and perspective-taking abilities after disease onset ( Arshad et al, 2020 ). From the current literature, we know that impairment in empathy, emotion recognition, fluency and executive functions are present also in non-demented ALS, sharing similarities with behavioral changes and cognitive decline in bvFTD ( Beeldman et al., 2018 ).…”