Abstract :
[en] Short-term memory (STM) precision has been defined as the resolution with which items are maintained in STM (Joseph et al., 2015). It has to be distinguished from STM capacity, which refers to the number of items that are recalled in STM (Miller, 1956; Cowan, 2010). So far, this concept has received little interest in the verbal STM domain. In two studies, we assessed the sensitivity to different degrees of phonological similarity between memory and probe items as a potential index of verbal STM precision. In Study 1, we assessed STM precision in 60 monolingual, French-speaking young adults. In Study 2, we aimed at taking advantage from the potential differences in STM precision stemming from differing language representations in 35 speakers of German, French, and English. In both studies, participants were presented auditory lists of 6 words. After a delay, a probe was presented, and participants had to decide whether it had been in the list or not. Negative probes showed different degrees of phonological proximity with the target word in the memory list. In Study 1, the lists were presented only in French, while in Study 2, the participants carried out the task in German, French and English. We also assessed comprehension and production of these three languages. Using Bayesian repeated measures ANOVA, we observed in both studies decisive evidence for an influence of phonological proximity on STM probe recognition performance: the more similar the negative probes to the target word, the higher the rate of false recognition. Study 2 revealed additionally that this effect was maintained across languages and that performance correlated positively with language proficiency, the best scores being reached in L1. Finally, we observed significant inter-individual variability in the sensitivity to phonological proximity. These studies suggest that memory-probe phonological similarity is an important variable for the development of measures of STM precision in the verbal domain and is stable across the languages spoken at different levels of mastery.
