Intentional and incidental odour-colour binding in working memory

The question of how features are bound together in working memory has become a topic of much research in recent years. However, this is typically focused on visual and/or auditory stimuli. The purpose of this study is to apply established feature binding procedures to investigate odour binding in working memory. Across three experiments, memory for intentionally and incidentally formed odour-colour pairings was tested. Experiment 1 showed that following explicit instruction to remember the odour-colour combinations, young adults can recall lists of 3-pairings at levels above that of chance and exhibit a recency advantage for the last pairing. In Experiment 2 participants were asked to prioritise the first pairing in the list or treat all pairings equally. We observed only limited evidence of prioritisation affecting the serial position function. Experiment 3 explored incidental odour-colour binding. Using a yes/no recognition procedure, accuracy did not differ for positive test probes presented in the same (bound) or different (unbound) colour to encoding. This study is one of the first to examine odour-colour binding in working memory and, taking the evidence together, suggests that odour-colour bindings can be formed in working memory; however, functionality may be limited compared to that of visual feature binding.