In this paper we introduce a novel way of quantifying typing expertise according to the ability to type without visual guidance from the keyboard (i.e., in a blind typing task). We present results of two experiments showing that performance in blind typing allows dissociating two profiles of typists, touch and non-touch typists. In Experiment 1, analyzing more than 100 typists, we show that performance in blind typing correlates with faster typing speed of lexical and non-lexical material, but not with low-level motoric skills. In Experiment 2, we show that touch and non-touch typists present differences in both written and spoken language production, but not language perception. Our results demonstrate that the characterization of “everyday touch typists” not only discriminates typing skills but may also capture distinct cognitive abilities. Spanning the fields of sensorimotor and linguistic processing, this study stresses the importance of considering language processing to understand typing skills.

This paper uses the signal detection theory (SDT) to investigate the contribution of visual information to two monitoring-dependent functions, metacognitive awareness of errors and error corrections. Data from two experiments show that complete removal of visual outcome results in a mild decrease in error awareness and a much more significant decrease in correction rates. Partially restoring visual information by including positional information (as in masked password typing) causes a modest but statistically significant improvement in correction performance. Interestingly, participants treat the change to the quality of information differently across the tasks, with more conservative behavior (avoiding false alarms) in the correction task. These findings show the SDT’s ability to quantify, in a graded manner, the contribution of specific types of information to monitoring in complex tasks, while also providing additional information about how participants handle the change to the quality of information in a task-dependent manner.

Geminates (or double letters) are a feature of many languages, including English. Studies of the spelling errors produced by individuals with orthographic working memory deficits have provided evidence that geminates are not produced as two in- dependent instances of the same letter. Instead, there must be a special mechanism in the orthographic system that produces geminates. Several theories have attempted to model such mechanisms. However, in most cases, the predictions of such theories have been tested using data from single-case neuro- psychological studies. In the current study, we re-evaluate these theories using the largest corpus of geminate errors in typing collected to date, and show that no theory can explain all the findings. We then propose an enhanced model of gem- ination that can.