Blind people have acute awareness of their own heartbeat: ScienceAlert

Blind people are better than sighted people at feeling their own heartbeats, according to a new study – suggesting that not being able to see as much from the outside leads to a heightened awareness of what what happens inside.

The researchers hooked up a pulse oximeter to 36 blind people and 36 people of the same age and sex with full sight. Although each participant’s heartbeat was scientifically measured, they were also asked to count their own heartbeats without checking their pulse or touching their own body in any way.

With 1.0 representing a perfect score, blind people scored an average accuracy of 0.78, while sighted people recorded an average of 0.63. It’s more of a proof of how other senses can be improved in visually impaired people.

“This suggests that brain plasticity after blindness leads to a superior ability to detect signals from the heart, which has implications for the study of body awareness and emotional processing in blind people.” to write the researchers in their published article.

Technically, this is called interoception, the sensitivity to stimuli inside the body. Until now, it was unclear how neuroplasticity in blind people – the way the nervous system moves to compensate for a lack of vision – might also affect interoception.

Although this is a relatively small study, it indicates a notable link. Interoception levels have also been associated with emotional processing – the extent to which we are able to perceive emotions in ourselves and others.

The question that this study does not answer is why interoception is enhanced in blind people, but this is something that can be addressed in future research. It could also be that the blind are picking up heartbeat signals from other areas of the body besides the heart, the team suggests.

“We know that heart signals and emotions are closely linked,” said neuroscientist Dominika Radziun of the Karolinska Institute in Sweden.

“For example, our heart beats faster when we feel fear. It is possible that blind people’s heightened sensitivity to signals from their own heart also impacts their emotional experiences.”

Interestingly, the two groups showed no major differences in actual heart rate or how they perceived they were monitoring it. This suggests that the gap between groups of participants is indeed related to interoception.

Different parts of the body related to the processing of heart signals, such as the anterior insula of the brain – a region of the insular cortexinvolved in the regulation of subjective feelings – could be analyzed specifically to further this research, suggest the authors of the new study.

Like many studies in blindnessthe results not only tell us more about what it’s like to live without sight and how the brain and body adapt, but also about the capabilities and versatility of the brain in general.

“This gives us important insights into the plasticity of the brain and how losing one sense can enhance others, in this case the ability to sense what’s going on inside your own body.” , said Radziun.

The research was published in the Journal of Experimental Psychology: General.