Publications

Abstract

Individual differences in cognitive abilities are ubiquitous across the spectrum of proficient language users. Although speakers differ with regard to their memory capacity, ability for inhibiting distraction, and ability to shift between different processing levels, comprehension is generally successful. However, this does not mean it is identical across individuals; listeners and readers may rely on different processing strategies to exploit distributional information in the service of efficient understanding. In the following psycholinguistic reading experiment, we investigate potential sources of individual differences in the processing of co-occurring words. Participants read modifier-noun bigrams like absolute silence in a self-paced reading task. Backward transition probability (BTP) between the two lexemes was used to quantify the prominence of the bigram as a whole in comparison to the frequency of its parts. Of five individual difference measures (processing speed, verbal working memory, cognitive inhibition, global-local scope shifting, and personality), two proved to be significantly associated with the effect of BTP on reading times. Participants who could inhibit a distracting global environment in order to more efficiently retrieve a single part and those that preferred the local level in the shifting task showed greater effects of the co-occurrence probability of the parts. We conclude that some participants are more likely to retrieve bigrams via their parts and their co-occurrence statistics whereas others more readily retrieve the two words together as a single chunked unit.

Abstract

In the following self-paced reading study, we assess the cognitive realism of six widely used corpus-derived measures of association strength between words (collocated modifier–noun combinations like vast majority): MI, MI3, Dice coefficient, T-score, Z-score, and log-likelihood. The ability of these collocation metrics to predict reading times is tested against predictors of lexical processing cost that are widely established in the psycholinguistic and usage-based literature, respectively: forward/backward transition probability and bigram frequency. In addition, the experiment includes the treatment variable of task: it is split into two blocks which only differ in the format of interleaved comprehension questions (multiple choice vs. typed free response). Results show that the traditional corpus-linguistic metrics are outperformed by both backward transition probability and bigram frequency. Moreover, the multiple-choice condition elicits faster overall reading times than the typed condition, and the two winning metrics show stronger facilitation on the critical word (i.e. the noun in the bigrams) in the multiple-choice condition. In the typed condition, we find an effect that is weaker and, in the case of bigram frequency, longer lasting, continuing into the first spillover word. We argue that insufficient attention to task effects might have obscured the cognitive correlates of association scores in earlier research.