You are entering the South American rainforest, following the lively call of a bird. Its song resonates among the trees during the day, but when night falls it dissolves into the silence of sleep. Or not? Thanks to a revolutionary discovery by researchers atUniversity of Buenos Aires now we can answer this question. Armed with electrodes, mathematical models and an insatiable curiosity, Argentine researchers have managed to crack the code of Kaskadi's singing dreams, giving us an unprecedented nocturnal symphony.
From waking to dreaming: a song without borders
The protagonist of this extraordinary research is the Sulphured pitango (Pitangus sulphuratus), also known as “Kaskadi” for the sound of its unmistakable call. This lively little bird, widespread throughout much of Central and South America, is famous for its territorial nature and the tripartite song with which it defends its space. During the day, the Kaskadi produces a characteristic vocalization, a sort of "trill" composed of short syllables, accompanied by the raising of the feathers on the head. It is a signal of defiance towards intruders.
But what happens when the Kaskadi falls asleep? His brain, particularly the area dedicated to daytime singing, remains active, showing patterns strikingly similar to those produced during wakefulness. Previous research has already shown that these brain patterns activate the bird's vocal muscles, allowing it to silently “play” a song during sleep. However, until now, no one had been able to decipher the content of these singing dreams.
Listening to the dreams of the Kaskadi
To unravel this mystery, researchers have implanted special electromyography (EMG) electrodes in the Kaskadi, capable of measuring the muscular response and electrical activity in the obliquus ventralis, the most important muscle for the production of song. By simultaneously recording EMG and song audio while the birds were awake and asleep, the scientists amassed a valuable database.
But how do you translate these muscle signals into audible singing? Here we enter the field of mathematical modeling. The researchers used a pre-existing dynamic model of the Kaskadi's sound-production mechanism, which breaks down what happens in the syrinx (the vocal organ of birds) into a series of equations.
For the last 20 years I have been working on the physics of birdsong and how to translate muscle information into song. In this way, we can use muscle activity patterns as parameters of a song production model, and synthesize the corresponding song.
Gabriel Mindlin, senior author of the study.
A window into the animal mind
By analyzing muscle activity during sleep, the researchers discovered consistent patterns corresponding to the trills produced by Kaskadi during daytime territorial disputes. Curiously, these “dream trills” were associated with the raising of the head feathers, just as during the day. Using the data collected, scientists managed to create the synthetic version of one of these trills. Poetry and science, in short: we have a taste of the melodies that populate the dreams of birds. Do you want to hear?
“I felt great empathy imagining that lone bird recreating a territorial dispute in his dream,” confesses Mindlin. “We have more in common with other species than we usually recognize.” This discovery not only brings us closer to understanding the bird mind, but also opens fascinating new perspectives for the study of the avian brain, animal dreams, and of their language. This methodology could be extended to other species, paving the way for a new era in the exploration of the animal mind. Who knows what other dreamlike melodies we might discover, from whales to elephants, from dolphins to primates. Each species could have its own “nocturnal soundtrack”, a symphony of dreams just waiting to be heard.
From Kaskadi onwards
The discovery of the Argentine researchers, as mentioned, fascinates me for its poetic value. But he also has profound scientific implications. Dreams have always been there one of the great mysteries of biology, an unexplored territory that hides the deepest secrets of the mind. Understanding how animals dream could help us shed light on the evolutionary and neurobiological mechanisms that govern this fascinating brain activity. And then this research reminds us how thin the boundary is between us and other species. Knowing that we share the experience of dreaming with creatures seemingly so distant from us is a thought that is both shocking and comforting. It reminds us that, beyond superficial differences, we are all part of the same great adventure of life on Earth.
While the Kaskadi doze (so to speak) on the branches, lulled by their nocturnal melodies, we can imagine what adventures they are having in their small, large dream worlds thanks to the pioneering work of researchers at the University of Buenos Aires. Perhaps one day we will understand the language of dreams enough to be able to converse with our feathered companions, in a duet that crosses the barrier between species and unites us in the wonder of conscious life.
