The role of stimulus material in determining release from proactive inhibition

The release from proactive inhibition (PI) paradigm has been widely used as a technique for exploring the encoding dimensions of short-term memory for verbal items. PI release data have been used not only to infer particular memory codes but also to index their relative salience. In the present study, the effects of manipulating the colour (red or black) in which the stimulus material is printed were investigated in two separate experiments. No release effect was obtained in the first, where common two-syllable words were presented. In the second, where consonant trigrams were presented, a large effect was found. Since the same colour feature was manipulated in each experiment, it is argued that this pattern of results has serious implications for the use of PI release data as a technique for mapping the encoding dimensions of short-term memory.