How could expert chess players play a chess with their eyes closed?
Most scientists attribute extraordinary memory performance to an enhanced ability to associate or organize the information to be memorized, rather than true photographic memory. For example, many expert chess players possess a remarkable capacity to recall the position of chess pieces at any point from a game. The ability to retain an accurate mental image of the chessboard permits these players to play multiple boards at a time ― even while they are blindfolded!

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I wonder why "even while they are blindfolded" appears in a logical aspect. How could expert chess players play a chess with their eyes closed? I don't understand it.

please help me!

Question

How could expert chess players play a chess with their eyes closed?
Most scientists attribute extraordinary memory performance to an enhanced ability to associate or organize the information to be memorized, rather than true photographic memory. For example, many expert chess players possess a remarkable capacity to recall the position of chess pieces at any point from a game. The ability to retain an accurate mental image of the chessboard permits these players to play multiple boards at a time ― even while they are blindfolded!

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I wonder why "even while they are blindfolded" appears in a logical aspect. How could expert chess players play a chess with their eyes closed? I don't understand it.

please help me!

Answer

Playing chess blindfolded and playing multiple chess games at once is well known in the chess world. I think the English is fine

Answer

Good players "see" the board in their mind when they plan a move or two ahead.  They may be able to recall all the moves of a game that they have played.

Top players are better.  They can play one or more games without looking at a physical board and pieces.  Of course, the quality of their play is reduced, but it is still impressive.

Answer

This passage requires more context, in my opinion. This is difficult for me to understand because "play multiple boards at a time" is unclear. Will gladly help further if you can provide more context (in essence: more of the passage...maybe a link to the webpage or article you're reading?)