Birds Share Mammalian Sleep Patterns
It has always been thought that only mammals enjoy the somewhat varied sleep patterns that we are all so familiar with, but now it seems that birds are capable of REM, slow-wave sleep, transition stages and quick spikes too. Recent research conducted on the zebra finch has resulted in some alarming findings.
Research conducted by Philip Steven Low and his colleagues at the Salk Institute for Biological Studies in San Diego, California, shows that songbirds have very similar sleep patterns to humans and other mammals. The findings, which were reported on in The Proceedings of the National Academy of Sciences, came from electroencephalograms which were conducted on the birds. The discovery comes quite unexpectedly since previously it was thought that a neocortex was needed in order for an animal to have these varied sleep patterns. Birds do not have a neocortex – a fact which up until now has made it very difficult to even attempt to study the sleep patterns in birds. Scientists have actually been wanting to conduct studies on sleeping birds because of evidence that supports the idea that sleep plays a role in song learning. However the lack of a neocortex has made it difficult or impossible to pick up proper electrical signals from the test subjects.
However, according to Dr. Low, it was all about “Location, location, location.” The team of researchers experimented with moving the EEG electrodes to various parts of the brain until they found the most suitable spot. Once the signals were coming through loud and strong, he devised an algorithm to analyze them with. These algorithms created a multidimensional grid – a sort of mathematical map – that revealed the structure of the bird’s sleep. By mapping out the results in this way it was much easier to find and interpret the different sleep patterns the bird was experiencing.
The results of the research show that a cortex is not necessary for a creature to experience structure sleep patterns. The algorithms created to understand the brain activity of the sleeping bird can also be used as a basis to help find structural changes in the sleep of humans who are struggling with neurological disorders. This may prove to be of much benefit in future medical advances in the years to come.