I am embarking on an innovative online psychology experiment using JavaScript to explore the human ability to swiftly recognize images. This study utilizes the RSVP (Rapid Serial Visual Presentation) paradigm, a prevalent method in psychophysics that isolates the feedforward, pre-attentive stages of visual processing. The goal is to display a series of images for short durations such as 30 ms, 50 ms, 70 ms, and so forth. Precision in presentation times is crucial for obtaining valid results. While traditional methods involve specialized software or equipment in a laboratory setting, I am exploring alternative options due to constraints. Although some level of error is expected when conducting this experiment in a browser, my aim is to minimize it to the greatest extent possible and assess the degree of imprecision that may occur.
Currently, the approach involves image preloading and utilizing setTimeout() to manage stimulus duration. Given that participants may be using different monitors with varying refresh rates and browsers, there are inherent challenges in maintaining consistent timing across platforms.
A visual inspection reveals inconsistencies in the timing of images with the existing methodology, suggesting significant variability. This aligns with existing literature indicating high levels of variation in brief presentation times.
Exploring potential tools to enhance timing precision in JavaScript becomes essential. Additionally, tools capable of measuring or estimating the actual screen display time of images would be invaluable. Exploring alternatives like compiling the sequence of images into a video or gif format could also offer improved control over timing aspects.