Research Article Writing with the Eyes: The Effect of Age on Eye-Tracking Performance in Non-Disabled Adults and a Comparison with Bimanual Typing Marco Caligari , 1 Marica Giardini , 2 Ilaria Arcolin , 2 Marco Godi , 2 Stefano Corna , 2 and Roberto Colombo 3 1 Istituti Clinici Scientifici Maugeri, IRCCS, Scientific Institute of Pavia, Integrated Laboratory of Assistive Solutions and Translational Research (LISART), Pavia, Italy 2 Istituti Clinici Scientifici Maugeri, IRCCS, Scientific Institute of Veruno, Division of Physical Medicine and Rehabilitation, Gattico-Veruno, Italy 3 Istituti Clinici Scientifici Maugeri, IRCCS, Scientific Institute of Veruno, Service of Bioengineering, Gattico-Veruno, Italy Correspondence should be addressed to Ilaria Arcolin; ilaria.arcolin@icsmaugeri.it Received 9 June 2021; Accepted 12 August 2021; Published 25 August 2021 Academic Editor: Ivan Volosyak Copyright © 2021 Marco Caligari et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Eye-tracking technology is advancing rapidly, becoming cheaper and easier to use and more robust. is has fueled an increase in its implementation for Augmentative and Alternative Communication (AAC). Nowadays, Eye-Tracking Communication Devices (ETCDs) can be an effective aid for people with disabilities and communication problems. However, it is not clear what level of performance is attainable with these devices or how to optimize them for AAC use. e objective of this observational study was to provide data on non-disabled adults’ performance with ETCD regarding (a) range of eye-typing ability in terms of speed and errors for different age groups and (b) relationship between ETCD performance and bimanual writing with a conventional PC keyboard and (c) to suggest a method for a correct implementation of ETCD for AAC. Sixty-seven healthy adult volunteers (aged 20–79 years) were asked to type a sample sentence using, first, a commercial ETCD and then a standard PC keyboard; we recorded the typing speed and error rate. We repeated the test 11 times in order to assess performance changes due to learning. Per- formances differed between young (20–39 years), middle-aged (40–59 years), and elderly (60–79 years) participants. Age had a negative impact on performance: as age increased, typing speed decreased and the error rate increased. ere was a clear learning effect, i.e., repetition of the exercise produced an improvement of performance in all subjects. Bimanual and ETCD typing speed showed a linear relationship, with a Pearson’s correlation coefficient of 0.73. e assessment of the effect of age on eye-typing performance can be useful to evaluate the effectiveness of man-machine interaction for use of ETCDs for AAC. Based on our findings, we outline a potential method (obviously requiring further verification) for the setup and tuning of ETCDs for AAC in people with disabilities and communication problems. 1.Introduction Eye-tracking technologies, i.e., technologies that automatically track the point of an individual’s gaze while that person views or interacts with a visual image, are widely used now in several research fields [1]. Since 1994, the field of language science has seen an exponential rise in the publication of eye-tracking research studies. With this technology, the position of the eyes is deter- mined based on light reflected from the curvature of the corneas and the position of the pupils. A low level of infrared light, which is invisible to humans, reflects off the eyes and a camera captures the images and computes the angle of reflection. A signal processing procedure matches the physical orientation of the eyes to specific x-y coordinates and maps them, through appropriate calibration, to the Hindawi Computational Intelligence and Neuroscience Volume 2021, Article ID 9365199, 9 pages https://doi.org/10.1155/2021/9365199