New research from the University of Tubingen suggests that brain activity in baby girls may be more intricate than in baby boys. Using magnetoencephalography (MEG), researchers found that the complexity of brain signals decreases faster in males as their nervous systems develop compared to females.
As per New Scientist, researchers employed MEG in 43 third-trimester fetuses and 20 babies aged 13 to 59 days old. Sound stimuli, comprising different beep arrangements, were used. For instance, one sequence included four beeps, each lasting 200 milliseconds and separated by 400-millisecond intervals. These sounds were transmitted to the fetuses through a "sound balloon" placed between the pregnant person's abdomen and the MEG sensors.
Subsequently, the team monitored their magnetic brain activity in response to the sound stimuli. They computed several metrics reflecting the complexity of the MEG signal, employing algorithms to gauge processing difficulty. The researchers clarified that in healthy adults, elevated neural complexity correlates with enhanced performance and swifter reaction times in executive functions like planning and decision-making. Conversely, reduced levels are linked with states wherein information processing capacity is diminished, such as during general anesthesia or non-rapid eye movement sleep.
Hence, the researchers hypothesized that MEG signal complexity would increase as gestation progressed in fetuses and as babies aged. Nonetheless, they were startled to discover that the decrease occurred notably quicker among male fetuses and babies compared to females.
The reason for this decrease is unclear, but experts believe that one possible explanation is that neural complexity measures different processes as the brain develops. "The developing brain eliminates cells and connections that are unnecessary, constraining the number of ways in which the brain can respond to a stimulus, said Frohlich.
The process of brain maturation entails the transition towards organized patterns of neural connections, instructing the brain on how to react to stimuli like the beeps in our study. A more mature brain exhibits fewer response options to the stimulus, resulting in lower complexity. However, if we were to examine spontaneous activity, the findings might differ, he elaborated.