| | Dorlands Medical Dictionary |
 | | anatomical snuff-box, a triangular depression on the dorsum of the wrist at its radial border formed between the tendon of the extensor pollicis longus medially and the tendons of the extensor pollicis brevis and abductor pollicis longus laterally, formed when the thumb is abducted and extended. |
 | | Skinner box, an experimental enclosure for testing animal conditioning, in which the subject animal performs (e.g., presses a bar or lever) to obtain a reward. |
 | | Yerkes discrimination box, a maze with a series of doors, used in the laboratory in studies of visual discrimination in animals; opening of the proper door produces a reward, but opening of the wrong door produces an electric stimulus. |
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