Directions:  Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.

As infants, we can recognize our mothers within hours of birth. In fact, we can recognize the1 of our mother's face well before we can recognize her body shape. It's2how the brain can carry out such a function at such a young age, especially since we don't learn to walk and talk until we are over a year old. By the time we are adults, we have the ability to distinguish around 100,000 faces. How can we remember so many faces when many of us find it difficult to3 such a simple thing as a phone number? The exact process is not yet fully understood, but research around the world has begun to define the specific areas of the brain and processes4for facial recognition.
Researchers at the Massachusetts Institute of Technology believe that they have succeeded in5 a specific area of the brain called the fusiform face area (FFA), which is used only for facial recognition. This means that recognition of familiar objects such as our clothes or cars, is from6in the brain. Researchers also have found that the brain needs to see the whole face for recognition to take place. It had been7  thought that we only needed to see certain facial features. Meanwhile, research at University College London has found that facial recognition is not a single process, but8 involves three steps. The first step appears to be an analysis of the physical features of a person's face, which is similar to how we scan the bar codes of our groceries. In the next step, the brain decides whether the face we are looking at is already known or unknown to us. And finally, the brain furnishes the information we have collected about the person whose face we are looking at. This complex9is done in a split second so that we can behave quickly when reacting to certain situations.