Altered empathy processing in frontotemporal dementia A task-based fMRI study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neurology

Background:

• Reduced empathy, particularly affective empathy, is a hallmark symptom of behavioural variant frontotemporal dementia (bvFTD).
• Empathy for pain (EFP) paradigms using functional magnetic resonance imaging (fMRI) reveal blood oxygen level dependent (BOLD) signal changes in brain regions affected by bvFTD, such as the anterior insula and cingulate cortex.

Approach:

• This study investigated empathy processing in 28 bvFTD patients and 28 controls using an established EFP fMRI paradigm.
• Participants underwent structural MRI, task-based fMRI, and resting-state fMRI, alongside the Interpersonal Reactivity Index (IRI) for empathic function assessment.
• Analyses included whole-brain and region-of-interest approaches, focusing on affective versus cognitive empathy networks.

Key Points:

• Healthy controls exhibited increased BOLD signal in EFP-related regions overlapping bvFTD atrophy areas (insula, anterior cingulate), along with the supramarginal gyrus and occipital cortex.
• bvFTD patients showed increased BOLD signal only in the supramarginal gyrus and occipital cortex, with significantly less activation than controls in affective empathy regions.
• Control empathic concern scores correlated with EFP-related BOLD signals, unlike bvFTD patients or other IRI subscales.

Conclusions:

• bvFTD is associated with reduced neural activity in key empathy processing regions, correlating with diminished affective empathy capacity.
• Resting-state fMRI revealed altered connectivity in empathy networks, particularly the ventral attention network, in bvFTD patients compared to controls.
• These findings highlight neural underpinnings of empathy deficits in bvFTD and their relationship to disease pathology.