The brain is incredibly good at recognizing familiar faces, even when they change dramatically. This happens in a split second. It can quickly figure out a person's age, gender, and who they are, even if the face is tilted, in different lighting, or has a different expression. But how does the brain do this so fast?  That's a mystery.

Scientists wanted to understand the brain's process. They used special tools to watch how the brain reacts to familiar faces. They showed people pictures of famous celebrities. These pictures changed in how the face was shown, the age of the person, and their gender. The participants had to do a simple task: notice if the face was the same as the one before. It was a race against time.

The brain starts recognizing a face in just 64 milliseconds. It begins with the specific view of the face. Then, at 75 milliseconds, it starts to see the face as a mirror image. Finally, at 89 milliseconds, the brain fully recognizes the face, no matter the angle. This is amazing because it happens so fast.

Age and gender information come in around the same time as the full face recognition. This means the brain processes these details together. It's like the brain is multitasking. The task given to the participants only affected the later stages of face processing. This suggests that the brain's initial face recognition is mostly automatic and doesn't need much thought.

The brain areas involved in this process are the occipital face area and the fusiform face area. These areas are more active for identity and age than for gender. This shows that the brain might prioritize recognizing who a person is and how old they are over their gender. This is important because it tells us how the brain works when it comes to faces.

The findings give new clues for building computer models of face recognition. These models could help in many areas, like security or helping people with face blindness. The brain's ability to recognize faces is a complex process. It involves many steps and brain areas working together. Understanding this process can help us appreciate the brain's amazing abilities.

How the Brain Recognizes Faces in a Flash

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