Research Uncovers Brain’s Ability to Generate Emotions Independent of Sensory Input

What role do our senses play in shaping our emotions? Do our brain and body react similarly when confronted with a terrifying scream, a mysterious shadow, or an unpleasant odor? And does experiencing lively music or witnessing a beautiful landscape evoke comparable feelings of joy?

In a groundbreaking study published in Science Advances, researchers have unveiled fresh insights into the complex relationship between emotion and perception.

Led by a team of Italian neuroscientists from the IMT School for Advanced Studies Lucca, in collaboration with the University of Turin, the study delves into whether the brain employs sensory-specific or abstract codes to construct emotional experiences.

“Emotion and perception are deeply intertwined, yet the precise mechanisms by which the brain processes emotional stimuli have remained elusive,” explains Giada Lettieri, a psychology researcher at the IMT School and the study’s lead author. “Our research tackles this fundamental question, offering crucial insights into how the brain organizes and interprets emotional information across various sensory modalities and based on past sensory experiences.”

To conduct the study, researchers screened the movie 101 Dalmatians for a group of 50 volunteers while monitoring their brain activity using functional magnetic resonance imaging (fMRI). The participants included individuals with typical sensory development, as well as congenitally blind and deaf volunteers, who experienced the movie through auditory or visual means, respectively. Additionally, a separate group of 124 participants were asked to express and rate their emotions while watching the movie, allowing researchers to anticipate the brain responses of individuals with and without sensory deprivation across emotions such as amusement, fear, and sadness.

“Incorporating individuals with congenital sensory deprivation—such as blind and deaf individuals—into the experiment enables us to dissect and decipher the influence of sensory experience on the neural mechanisms underlying emotions,” explains Luca Cecchetti, a researcher at the IMT School and the study’s senior author and supervisor. “Our findings demonstrate that emotional categories are represented in the brain irrespective of sensory experience and modalities. Specifically, a distributed network encompassing sensory, prefrontal, and temporal brain regions collectively encode emotional stimuli. Notably, the ventromedial prefrontal cortex emerges as a crucial site for encoding an abstract representation of emotions, independent of prior sensory experience or modality.”

The existence of an abstract coding of emotions in the brain suggests that while we may perceive emotions as being directly influenced by external stimuli, it is our brain’s intrinsic wiring that generates emotional significance regardless of sensory capabilities.

“In a world where individuals with sensory deprivation are often overlooked, it is imperative to comprehend how mental faculties and their corresponding neural representations can develop and refine in the absence of sensory input, thereby advancing our understanding of emotions and the human brain,” concludes Lettieri.