This is probably old news for neuroscientists and YouTube regulars, but it was news to me. I thought I would write a post about it, in case, like me, you are not one of the 4 million or so who have already seen the video of Snowball, the dancing Cockatoo, or heard about how he inspired neuroscientist Aniruddh Patel to investigate the basis of his unusual talent and discover a unique connection between human brains and bird brains.
In a NY times feature published last week (1), Dr. Patel describes how his curiosity was piqued when a friend showed him Snowball’s famous YouTube video. He was amazed because the bird was exhibiting a behavior thought to be unique to humans–the ability to move in time with a beat.
When you dance or tap your foot in time to a rhythm, you are displaying an ability known as beat perception and synchronization (BPS). This ability is thought to be associated with the capacity for vocal learning, which involves links between the auditory and motor systems in the basal ganglia and supplementary motor areas of the brain. This hypothesis predicts that only vocal learning species (such as humans, parrots, dolphins, and seals) who (presumably) have these neural connections, and not vocal nonlearners (like dogs, cats, and chimps) would be capable of BPS. But before Snowball, no instance of this behavior outside of humans had been verified.
Dr. Patel’s paper, published in Current Biology in 2009 (2), describes a detailed study of Snowball, the first observed case of beat perception and synchronization in a non-human species. To rule out the possibility that Snowball could just be imitating the movements of a human dancing off-camera, or randomly moving in a manner that occasionally coincided with the beat, the authors performed and in-depth study of his movements as he danced.
By adjusting the tempo of the music, they were able to analyze whether the bird’s movements were truly influenced by the changing beat. This involved a complex analysis of the timing and number of “head bobs” and subsequent comparison of their relationship to the changing tempo of the music. They found that Snowball’s head bobs were indeed closely aligned to the changing beat.
A second paper in the same issue of Current Biology (3) did an anaylsis of other YouTube videos for this type of behavior and found 15, all songbirds and mostly from the parrot family. These two papers provide support for the theory that BPS involves similar neural pathways to those involved in vocal learning. The paper concludes that there is a need for further study to find out whether BPS is indeed confined, as suggested by these findings, to vocal learners. Particularly, further study of non-human primates, to confirm that they lack this ability, and studies in seals and dolphins—to find out if they share this ability—would be fascinating.
I find the role of YouTube in this discovery interesting. The chance observation by Dr. Patel of the Snowball video, and his realization of the significance of what he was seeing, led to an advancement of scientific knowledge and the discovery of a previously unknown connection between the brain function in humans and songbirds. To me, this is reminiscent of other “chance” discoveries in the history of science, where a curious and open minded scientist was able to capitalize on an unexpected observation. For example, Fleming’s famous discovery after noticing the effect of Penicillium fungal contamination on his bacterial culture plates. The history of science is littered with these types of stories, but this may be the first one where YouTube played a part!
- Dreius, C. Exploring Music’s Hold on the Mind. New York Times June 10, 2010.
- Patel, A., Iversen, J., Bregman, M., & Schulz, I. (2009). Experimental Evidence for Synchronization to a Musical Beat in a Nonhuman Animal Current Biology, 19 (10), 827-830 DOI: 10.1016/j.cub.2009.03.038
- Schachner, A., et al. (2009) Spontaneous motor entrainment to music in multiple vocal mimicking species. Curr. Biol. 19, 831–836.