Simply put, the science is still out on brain games. When put to rigorous, short-term scientific trials, brain games sometimes show an effect on cognitive ability and sometimes do not. The rise in popularity of brain games is also too new for any long-term studies of the method to have shown results one way or another. Anecdotally, many people do feel as though brain games have helped with cognition, so here is an example of an increasingly demanding brain game you can try if you choose. Begin by opening a large, clear version of this image. Starting at the top, move from left to right and top to bottom while calling out the direction the eyes are looking, e.g. ”down, left, up, right…” Time yourself as you go through the faces, and try to do it without any errors first within thirty seconds, then within fifteen seconds. Once you’ve gotten quick at calling the directions, try calling the directions from the face’s perspective instead—as if you were the face looking out from the page, e.g. ”down, right, up, left…" This approach is more difficult because it requires one additional processing step to correct for the face’s perspective. As with the first trial, time yourself and try to complete the picture without error at different milestones—thirty seconds, then fifteen seconds. Return to the exercise from step 2, but this time point your finger in the opposite direction of the one you’re saying aloud for each face, e.g. ”down [point up], left [point right], up [point down]…" This one will be even more difficult because you’ve added a motor skill component to the verbal component.  Similar to the idea behind why musical training can improve processing speed, this exercise requires the coordination of multiple brain modalities—visual to interpret the information in the picture, verbal to say the direction aloud, and motor to point in coordination with the rest. You can continue adding even more components to the exercises as well, calling out the face’s perspective direction only when you reach green faces or on...

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Write a summary of the previous text in Vietnamese:
Phóng to bức hình này bằng cách mở nó ở cửa sổ mới. Đọc to các hướng mà mắt trên bức hình đang nhìn về. Bắt đầu tập thực hành với chính khuôn mặt của bạn. Dùng bức vẽ đầu tiên để thực hành, nhưng bạn nên kèm theo hành động chỉ trỏ bằng ngón tay. Mở rộng vốn tiết mục trò chơi trí tuệ.