Effects of task complexity and working memory capacity on L2 reading comprehension

The present study investigated whether cognitive task complexity affects second language reading comprehension and whether working memory capacity moderates the influence of task complexity. Fifty-two Korean undergraduate students were randomly assigned to either simple or complex condition and read two TOEFL passages while answering multiple-choice reading comprehension questions. Unlike simple versions that included coherent texts, complex versions contained texts whose paragraphs were disarranged and additionally required participants to order them coherently. A forward digit span test and a nonword repetition test were used to measure the participants' phonological short-term memory, and a backward digit span test and an operation span test were employed to assess their complex working memory. The results revealed that task complexity did not affect reading comprehension scores, although participants perceived the complex tasks significantly more demanding. Also, under the complex condition, participants benefited from higher nonword span scores when answering reading comprehension questions.