Are masked-stimuli-discrimination-tests in masked priming studies measures of intelligence?—An alternative task for measuring inspection time

Traditional inspection time tasks involve the masked presentation of simple stimuli (usually two lines) which have to be categorized in a forced-choice discrimination task. There is now broad evidence, that this measure captures some aspect of low-level cognitive ability. In this paper, we suggest an alternative paradigm for measuring the mechanism underlying IT which originates from the field of masked priming studies. In masked priming studies, typically participants’ awareness of the masked primes is accessed by a masked-stimuli-discrimination-test at the end of the experimental session. In contrast to traditional inspection time procedures, masked-stimuli-discrimination-tests involve usually the presentation of more complex stimuli (e.g., words) and more complex decisions (e.g., about the valence of stimuli). In two studies presented here involving independent samples the performance in masked-stimuli-discrimination-tests has been shown to correlate substantially with psychometric intelligence measures. We argue that this test can be seen as a ‘conceptual replication’ of traditional IT tests. This bears several implications for masked priming studies but also for studies on the elementary cognitive correlates of human intelligence.