There are two types of catch trials: false positive and false negative. […] False-negative catch trials are meant to determine if a subject has fallen asleep or has an otherwise reduced ability to respond during a test. If a subject misses a brighter stimulus than has previously been seen, it is assumed that this represents a bona fide false-negative catch trial.

The biennial also includes a sprawling cityscape by Chris Burden incorporating thousands of model buildings, cranes and automobiles, a maximalist vision where Mr. Ashkin's is minimalist.

2004, Simon Popple; Joe Kember, Early Cinema: From Factory Gate to Dream Factory, page 92:

Beijing’s reshuffle of officials in Xingjiang might herald a hardening of repression against Uighurs, an academic at the Institute for National Defense and Security Research said.