The unreliability of egocentric bias across self–other and memory–belief distinctions in the Sandbox Task

Humans are often considered egocentric creatures, particularly (and ironically) when we are supposed to take another person's perspective over our own (i.e. when we use our theory of mind). We investigated the underlying causes of this phenomenon. We gave young adult participants a false belief task (Sandbox Task) in which objects were first hidden at one location by a protagonist and then moved to a second location within the same space but in the protagonist's absence. Participants were asked to indicate either where the protagonist remembered the item to be (reasoning about another's memory), believed it to be (reasoning about another's false belief), or where the protagonist would look for it (action prediction of another based on false belief). The distance away from Location A (the original one) towards Location B (the new location) was our measure of egocentric bias. We found no evidence that egocentric bias varied according to reasoning type, and no evidence that participants actually were more biased when reasoning about another person than when simply recalling the first location from memory. We conclude that the Sandbox Task paradigm may not be sensitive enough to draw out consistent effects related to mental state reasoning in young adults.


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o Yes (1) o No (2) Q48 Now please click right in the centre of this left cross and right in the centre of this right cross. Try to be as accurate as possible, and again if the mouse cannot fall exactly in the centre please ensure you do the same for each click. You can try as many times as you Q28 Now try to find as many words as you can in the puzzle below and type them in the field at the bottom of the page. You (3) Q38 Now try to find as many words as you can in the puzzle below and type them in the field at the bottom of the page. You (3) Q48 Now try to find as many words as you can in the puzzle below and type them in the field at the bottom of the page. You (2) Q105 I understand that all personal information will remain confidential and that all efforts will be made to ensure that I cannot be identified (except as might be required by law).
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o Yes (1) o No (2) Q117 I agree that data gathered in this study may be stored anonymously and securely, and may be used for future research. First you will be asked to click on various locations on your screen (this helps us with calibration).
Second (the main part of the study) you will read some short stories about objects being hidden. Please pay careful attention to the story and the accompanying visual information. After each story you will have 20 seconds to find words in a wordsearch. After each wordsearch you will be asked a question about the story that you have just read. Total experiment time is approximately 10 minutes.
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Q48 Now please click right in the centre of this left cross and right in the centre of this right cross. Try to be as accurate as possible, and again if the mouse cannot fall exactly in the centre please ensure you do the same for each click. You can try as many times as you like.

Q3
Now try to find as many words as you can in the puzzle below and type them in the field at the bottom of the page. You (2) Q105 I understand that all personal information will remain confidential and that all efforts will be made to ensure that I c annot be identified (except as might be required by law).
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Second (the main part of the study) you will read some short stories about objects being hidden. Please pay careful attention to the story and the accompanying visual information. After each story you will have 20 seconds to find words in a wordsearch. After each wordsearch you will be asked a question about the story that you have just read. Total experiment time is approximately 10 minutes.
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Q62 Participant Debriefing Sheet:
Thank you for taking part in our study.

What was the study about?
The experiment you took part in is part of a larger study designed to test how people use their own knowledge when having to take into account what others remember or believe. We know that adults tend to expect that other adults know what they themselves know. The critical component of this study was to see whether you were influenced by where you knew an object to be when you had to imagine where someone else remembered or believed it to be. Q54 Before you decide to take part in this study it is important for you to understand why the research is being done and what it will involve. Please take time to read the following information carefully and discuss it with others if you wish. A member of the team can be contacted if there is anything that is not clear or if you would like more information. Take time to decide whether or not you wish to take part.  (2) Q105 I understand that all personal information will remain confidential and that all efforts will be made to ensure that I c annot be identified (except as might be required by law).

End of Block: Participant Info
o Yes (1) o No (2) Q117 I agree that data gathered in this study may be stored anonymously and securely, and may be used for future research. First you will be asked to click on various locations on your screen (this helps us with calibration).
Second (the main part of the study) you will read some short stories about objects being hidden. Please pay careful attention to the story and the accompanying visual information. After each story you will have 20 seconds to find words in a wordsearch. After each wordsearch you will be asked a question about the story that you have just read. Total experiment time is approxim ately 10 minutes.
The calibration process is next...

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Q48 Now please click right in the centre of this left cross and right in the centre of this right cross. Try to be as accurate as possible, and again if the mouse cannot fall exactly in the centre please ensure you do the same for each click. You can try as many times as you like.

Q3
Now try to find as many words as you can in the puzzle below and type them in the field at the bottom of the page. You (2) Q105 I understand that all personal information will remain confidential and that all efforts will be made to ensure that I c annot be identified (except as might be required by law).
o Yes (1) o No (2) Q117 I agree that data gathered in this study may be stored anonymously and securely, and may be used for future research. First you will be asked to click on various locations on your screen (this helps us with calibration).
Second (the main part of the study) you will read some short stories about objects being hidden. Please pay careful attention to the story and the accompanying visual information. After each story you will have 20 seconds to find words in a wordsearch. After each wordsearch you will be asked a question about the story that you have just read. Total experiment time is approxim ately 10 minutes.
The calibration process is next...

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Q48 Now please click right in the centre of this left cross and right in the centre of this right cross. Try to be as accurate as possible, and again if the mouse cannot fall exactly in the centre please ensure you do the same for each click. You can try as many times as you like.

Q3
Now try to find as many words as you can in the puzzle below and type them in the field at the bottom of the page. You (2) Q105 I understand that all personal information will remain confidential and that all efforts will be made to ensure that I c annot be identified (except as might be required by law).
o Yes (1) o No (2) Q117 I agree that data gathered in this study may be stored anonymously and securely, and may be used for future research. First you will be asked to click on various locations on your screen (this helps us with calibration).
Second (the main part of the study) you will read some short stories about objects being hidden. Please pay careful attention to the story and the accompanying visual information. After each story you will have 20 seconds to find words in a wordsearch. After each wordsearch you will be asked a question about the story that you have just read. Total experiment time is approximately 10 minutes.
The calibration process is next...  (2) Q105 I understand that all personal information will remain confidential and that all efforts will be made to ensure that I c annot be identified (except as might be required by law).

End of
o Yes (1) o No (2) Q117 I agree that data gathered in this study may be stored anonymously and securely, and may be used for future research. First you will be asked to click on various locations on your screen (this helps us with calibration).
Second (the main part of the study) you will read some short stories about objects being hidden. Please pay careful attention to the story and the accompanying visual information. After each story you will have 20 seconds to find words in a wordsearch. After each wordsearch you will be asked a question about the story that you have just read. Total experiment time is approximately 10 minutes.
The calibration process is next... Thank you for taking part in our study.

What was the study about?
The experiment you took part in is part of a larger study designed to test how people use their own knowledge when having to take into account what others remember or believe. We know that adults tend to expect that other adults know what they themselves know. The critical component of this study was to see whether you were influenced by where you knew an object to be when you had