You can recognize a person almost as well by their breath as by their voice

Breathing patterns also reflect sleep, body mass index, anxiety and depression.

This was revealed when Israeli researchers Timna Sorokan led to monitor the breathing of about a hundred test subjects for a day. The study was published Current Biology in the journal.

Respiratory is, according to researchers, a subtle window into the functioning of the brain.

It is regulated by an extensive network of nerves, the pacemaker of which is located in the brain stem. The system receives a huge amount of sensory information from different parts of the body and, based on it, regulates the speed and depth of each inhalation and exhalation.

The study focused on nasal breathing, because the nose conveys continuous feedback to the brain. Sensitive pressure sensors measured airflow in both nostrils, six times per second.

Researchers found that individuals could be identified with 96.8 percent accuracy based on 20–100 traits. Among them were the amount of air inhaled, the length of pauses and asymmetry between the nostrils. Recognizability was maintained for at least two years.

Breathing patterns were also linked to the sleep-wake state, body mass index and even psychological traits, which had been mapped through questionnaires.

The researchers were able to predict, for example, the depression questionnaire score from the breathing data. According to them, breathing could become a new metric for monitoring the brain and mental health.