Testees are shown images of ambiguous pictures, and asked to describe what they see. Responses are analyzed to discover the testee's hidden thoughts.

研究者会给参与测验的人观看一些意义不明的图片，并让他们描述其所见，通过这些就可以分析出测验者的潜在想法。

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"I saw from my examination that if I had any hidden agendas or any bad thoughts or anything like that, that it would have come out, " he said.

CNN: Police in Tennessee town must take polygraphs

Her words helped me to discover that there was a hidden place in her mind which housed deeper thoughts.

CNN: ASIANOW - TIME Asia | Young China | The Pen is Nastier Than the Sword--Page 2