Babies may not question why they are so incredibly tired during the long hours they sleep but their brain scans may have discovered something surprising about the human condition: As infants sleep both brain activity and facial touch share the same pattern.
However researchers at MedUni Vienna in collaboration with the University Hospital of Hospital for Children (the University Hospital 3) Klinikum rechts der Isar in Leipzig and Monash University in South Australia have found a striking difference which could provide clues to help end-of-life decisions for newborns. In a study published in The Lancet Oncology the researchers compared brain activity patterns in 23 premature babies to 19 full-term infants. Initially through the use of an EEG cap on their faces they were then also able to identify the activity patterns of single infants and periods of comas (absence of breathing).
We found that both distracted infants and full-term infants are able to identify events on the outside world. Several of the infants also showed an overwhelming desire to look at the screen and touch it. From this finding it was clear that the brain activity patterns of newborns are distinct from those of 20-24 term infants and were current at about the time of what seems to have been a very long period of sleep explains head of the study Prof. Peter Styth of MedUni Viennas Department of Laboratory Medicine I.
It was previously assumed that this process would be patterned by stimulation of the brain. We tried that with toys and blankets and found no effect. But our brain scan findings were unexpectedly different: And there also seems to be a simple way of determining the brain activity explains Styth.
He and his colleagues decided to examine whether an EEG cap can reveal the specific brain activity tapped by the newborns. In principle this cap should detect the brain activity patterns of a newborn by solely registering the touch of the face towards the amniotaped device and vice versa. The EEG cap should therefore detect the sound of a newborn without any external stimulation Styth explains. In principle infants could look to the EEG cap through a raised and secreting neck and not feel any need for them to touch it. The EEG cap can therefore be implemented anywhere in the body without any physical sensation.
However in practice this job is not only for the 24-hour head as with many of us but also for the tiny pill-sized EEG cap motors in every ear. In our study a common problem was that the EEG cap motor could be permanently damaged. Notably EEG caps are sometimes nearly impossible to lose or replace yet here the cap moved also to the ear and it kept functioning right up to about 25 months after you stopped taking it. It could be due to the fact that there is not enough pressure on the sleeping little brain who stays sympathetic for a long time adds the neurophysiologist.
At that time the EEG cap already was almost fully functional for 27 months so it is even less difficult to find a permanent replacement for an EEG cap in the head. This is particularly true in cases when the device retires or is assigned to another patient like for a brain surgery. For example there is not always a replacement for an EEG cap. The electrodes are widely available yet they are of minimal quality and engineering. This means that the EEG caps supply often lasts until about ten years after its set off in the ear Styth says.
For the EEG cap to be able to detect an external sound however about a tenth of the EEG stimulation force in babies is required after they sleep. This happens for example in the short sleep episodes that happen while the baby is sleeping. This sounds like a break down in for example brain development (along with normal activity during this period) Styth reflects. While these short sleep episodes give you a false sense of being asleep disturbingly they also allow the EEG cap to record the brain activity bouncing back through the head. It is perhaps therefore that the brain activity of newborns during the absence of light seems to drop off and the brain is not selected to process sound information as it would normally do during a full-blown sleep.