Interoception Primes Emotional Processing: Multimodal Evidence from Neurodegeneration.

Area of Science:

• Cognitive Neuroscience
• Behavioral Neurology
• Neuroimaging

Background:

• Interoceptive priors are recognized as key modulators of negative emotions.
• Experimental manipulation of emotion priming via interoception and its multimodal signatures in neurodegenerative diseases remain underexplored.

Purpose of the Study:

• To investigate the impact of interoceptive priming on emotion recognition across healthy controls and neurodegenerative disease models.
• To explore the neural correlates, including EEG and brain connectivity, associated with interoceptive-emotional processing.

Main Methods:

• Developed a novel task involving interoceptive and exteroceptive priming conditions.
• Recruited 114 participants: healthy controls (HCs), behavioral variant frontotemporal dementia (bvFTD), Parkinson's disease (PD), and Alzheimer's disease (AD).
• Measured online EEG heart-evoked potentials (HEP) and analyzed brain structural and functional connectivity.

Main Results:

• Healthy controls showed enhanced negative facial emotion recognition (FER) post-interoception; bvFTD and PD patients exhibited disruptions.
• bvFTD patients uniquely showed impaired interoceptive accuracy and disrupted salience network connectivity.
• Increased HEP modulations were observed in HCs and AD, correlating with insula/ACC volume and salience/executive network connectivity.

Conclusions:

• Interoception significantly modulates emotion processing, with distinct disruptions observed in neurodegenerative conditions.
• Findings reveal specific pathophysiological markers for bvFTD, involving interoceptive accuracy and network connectivity.
• The study highlights the multidimensional role of interoception in emotion and neurodegeneration, informing future research and clinical applications.