Sentence:  The authors set about answering this fundamental question through a detailed investigation of the patient 's ability , tactually , ( 1 ) to perceive <WSD>figure</WSD> and ( 2 ) to locate objects in space , with his eyes closed ( or turned away from the object concerned ) . 
Meaning of the word marked with <WSD> tags:  a combination of points and lines and planes that form a visible palpable shape