This study investigated whether the modality effect of content presentation modes on students’ cognitive load and listening comprehension depends on the moderating effect of the learners’ language proficiencies in a mobile learning context. One hundred and sixty-two students majoring in English in a technology university used personal digital assistants (PDAs) as the learning tool for a mobile listening comprehension activity. Participants were randomly assigned to one of two presentation modes: (1) a single mode in which students were engaged in auditory materials only and (2) a dual mode in which they were exposed to audio and textual inputs simultaneously. Hierarchical regression was employed to examine the moderating effect of the learners’ proficiencies. The results confirmed the moderator role of English proficiency on cognitive load: students with lower proficiency appeared to be more perceptive of the text aid. However, the moderating effect was not obtained on the task performance in that students provided with the dual mode outperformed their single mode counterpart across the proficiency level. This study recommends that written text be displayed when students are engaged in a mobile English listening comprehension task to reduce learners’ cognitive load. The study also provides pedagogical implications for mobile language learning.
The effect of cognitive load (CL) on speech recognition has received little attention despite the prevalence of CL in everyday life, e.g., dual-tasking. To assess the effect of CL on the interaction between lexically-mediated and acoustically-mediated processes, we measured the magnitude of the “Ganong effect” (i.e., lexical bias on phoneme identification) under CL and no CL. CL consisted of a concurrent visual search task. Experiment 1 showed an increased Ganong effect under CL. A time-course analysis of this pattern (Experiments 2 and 3) revealed that the Ganong effect decreased over time under optimal conditions, but it did not under CL. Thus, CL appears to be delaying (and perhaps preventing) listeners’ ability to rely on fine phonetic detail to perform the sub-lexical task. This finding, along with an absence of measurable effects at the post-lexical level (Experiment 4) or at the lexical level (Experiment 5) and a clear negative effect of CL on perceptual discrimination (Experiment 6), suggests that the increased reliance on lexically-mediated processes under CL is the cascaded effect of impoverished encoding of the sensory input. Ways of implementing a link between CL and sensory analysis into existing models of speech recognition are proposed.
from the Journal of Memory and Language
On the flexibility of grammatical advance planning during sentence production: Effects of cognitive load on multiple lexical access.
Three picture–word interference experiments addressed the question of whether the scope of grammatical advance planning in sentence production corresponds to some fixed unit or rather is flexible. Subjects produced sentences of different formats under varying amounts of cognitive load. When speakers described 2-object displays with simple sentences of the form “the frog is next to the mug,” the 2 nouns were found to be lexically–semantically activated to similar degrees at speech onset, as indexed by similarly sized interference effects from semantic distractors related to either the first or the second noun. When speakers used more complex sentences (including prenominal color adjectives; e.g., “the blue frog is next to the blue mug”) much larger interference effects were observed for the first than the second noun, suggesting that the second noun was lexically–semantically activated before speech onset on only a subset of trials. With increased cognitive load, introduced by an additional conceptual decision task and variable utterance formats, the interference effect for the first noun was increased and the interference effect for second noun disappeared, suggesting that the scope of advance planning had been narrowed. By contrast, if cognitive load was induced by a secondary working memory task to be performed during speech planning, the interference effect for both nouns was increased, suggesting that the scope of advance planning had not been affected. In all, the data suggest that the scope of advance planning during grammatical encoding in sentence production is flexible, rather than structurally fixed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)