Implicit learning refers to people’s tendency to acquire complex regularities or patterns without intention or awareness (Reber, 1989). Given regularities are acquired without intention, and largely unconsciousness, implicit learning is often considered to occur without attention. The processes responsible for such learning were once contrasted with a selective intentional “system” (Guo et al., 2013; Jiang & Leung, 2005). However, more recent researches show that actually implicit learning processes are highly selective (Eitam, schul, & Hassin, 2009; Eitam et al., 2013; Tanaka, Kiyokawa, Yamada, Dienes, & Shigemasu, 2008; Weiermann & Meier, 2012). Therefore it is necessary to do more exploration about the roles of attention in implicit learning. So far, all previous Artificial Grammar Learning (AGL) studies used visual stimuli. Thus, it remains unclear whether AGL may be due to the presence of a visual regularity. To investigate the generality of effect of selective attention on AGL, we extend the experimental materials to auditory stimuli.
90 college students were recruited in two experiments. Sequences of letters and sequences of digits with different grammar rules were presented simultaneously through Dichotic listening technology. In Experiment 1, one group of participants were instructed to memorize the sequences of letters; another, the sequences of digits. In Experiment 2, all participants were instructed to memorize the above two types of sequences.
Results showed that: (1) when only one of the two stimulus dimensions was selected to attend (Experiment 1), participants learned the structure underlying the selected, but not that one of the ignored dimension; (2) when both stimulus dimensions were selected to attend, both structures were learned by participants (Experiment 2). These findings revealed that participants learned only the grammar for the dimensions to which they are attended.
The results of two studies strongly suggest that AGL occurs with auditory stimuli and visual perceptual learning is not necessary. The effect of selective attention on AGL is applicable across modalities, it is not only suitable for visual stimulus, but also applies to the auditory stimulus.