A team of researchers has managed for the first time to monitor the brain of a chicken embryo and has shown thathigher brain activity, which enables the execution of complex tasks, begins long before the egg hatches. In the study, which is published in the prestigious journalCurrent BiologyResearchers from the Carlos III University of Madrid (UC3M) participate.
In their experiments, the scientists obtainedthree-dimensional imaging with the aid of X-ray computed tomography (CT) and positron emission functional imaging (PET) techniquesto analyze how the chicken embryo reacted when exposed to a sound that will have a meaning when it is born (for example, that of a hen that alerts of a danger). And they observed that, in effect, the activity increased and the chicken brain “woke up”, that is, it went from a state of sleep to one of wakefulness, especially in the final phase of embryonic development (the final 20%). However, they have found that the same does not happen when the sound is a very similar noise but without meaning for the chicken.
These findings have implications for both advancing understanding of chicken brain development and that of human fetuses. Until now, pediatricians are still questioning the effects that external stimuli – such as music – may have on a brain still in training. The new proof thatthe brain of birds is able to recognize an external stimulus and wake up much earlier than previously thought, indicate that inthe embryo’s brain is already developing circuits capable of monitoring the environment in the same way that an adult brain does, the scientists conclude. “For the first time we have designed a procedure by which we can observe and measure the changes in brain activity of the embryo, oscillating between phases of sleep and wakefulness without interfering with its normal development,” says Juan José Vaquero, from the UC3M Department of Bioengineering.
