According to a study by two UCL researchers, 4 to 6-month-old babies are able to spot pictures of faces and of objects such as tools, animals or plants presented in natural scenes, with extraordinary speed. The study was recently published in the scientific journal eLife. Researchers Adélaïde de Heering and Bruno Rossion recorded the electrical activity in the brains of first fifteen, then a dozen, babies using 32 electroencephalogram (EEG) sensors (electrodes). Every second, six pictures of visual objects were shown to the babies, in sequences lasting 20 seconds, i.e. 120 images per 20-second sequence. Science had already established that young children are able to spot faces in pictures from an early age, but previous tests had shown it took them several seconds to spot the faces.
In this new study, a face (in many different forms) appeared every 5 pictures, resulting in two frequencies the researchers found interesting: 6 hertz (for all pictures containing visual objects but no faces) and 1.2 Hz (corresponding to a specific response to a pictures containing a face).
The 1.2 Hz response to faces was observed in 4 to 6-month-old babies, in the right hemisphere, the hemisphere that is responsible for face recognition in the adult brain.