The effect of coffee craving on memory and feeling-of-knowing judgement accuracy

Broadly, the aim of this study was to replicate the finding that craving‚ÄövÑvÆthat is, the intense desire for a substance‚ÄövÑvÆinhibits cognition, and to see whether this inhibition extends to metacognition. Specifically, this study sought to determine whether coffee craving inhibits memory and feeling-of-knowing (FOK) judgement accuracy. Sixty-seven participants were randomly allocated to a craving or control group. On the day of testing, the craving group abstained from coffee and completed a coffee exposure and imagery task during the experiment. The control group drank coffee as normal and completed a matched exposure and imagery task (jug of water and a holiday). Participants endeavoured to memorise 100 cue-target word pairs. Following an attempt to recall the target word, participants provided a FOK judgement regarding the likelihood of selecting the target in a four-alternative forced choice task (4AFC). Participants then completed the 4AFC task. The control group recalled significantly more target words and selected the correct target word in the 4AFC task significantly more than the craving group, but there was no difference between the two groups in FOK judgement accuracy. These results suggest that although craving inhibits memory, assessment of the quality of one's memory when information cannot be recalled remains intact.