Scientists Wake Up Chicken Embryo Brains
Posted on May 14, 2012
Researchers managed to arouse a chicken embryo inside an egg by exposing it to a sound that would have meaning after its birth, such as the sound of a chicken warning others of danger. However, the study demonstrated that the animal does not have the same reaction when it is exposed to a sound that is similar, but that has no special meaning for the chick. The image above is an X-ray computed tomography scan of a chicken embryo skeleton inside its egg (in grayscale), together with the functional image of positrons representing, in color, the capture of glucose in the spinal cord, in the brain stem and in the embryo's brain.
This technique combining sub millimeter-resolution brain positron emission tomography (PET) and structural X-ray computed tomography (CT) was used to study the brains of chicken embryos. The scientists created a non-invasive technique that provides three-dimensional images of brain function in animal models, with sub-millimetric resolution.
At the youngest ages, the chicken embryos showed a lot of spontaneous behavioral movements, but their higher-brain regions were completely inactive. At about 80% of the way between conception and birth, activity in higher-brain regions appears, showing states resembling sleep. At this stage, the scientists say it becomes possible to "wake up" the chicken embryo brains by playing loud, meaningful sounds to them. The researchers say their work "shows embryo brains can function in a waking-like manner earlier than previously thought, and, like adult brains, have neural circuitry that monitors the environment to selectively wake the brain up during important events." Take a look:
Participants in the study included Evan Balaban (McGill University, Montreal), Manuel Desco (Gregorio Marampmn General University Hospital of Madrid and UC3M) and Juan Jose Vaquero (UC3M). The research was published here in Current Biology.