Letter by Galileo to Leonardo Donato, 1609
Some very short notes about the history of the arrow as a graphic sign (there are four previous posts on this topic in italian: 1, 2, 3, 4).
The discussion started from the article “Mapping symbols to response modalities: Interference effects on Stroop-like tasks”(pdf) presenting a Stroop-like experiment on the interference between a word and an “arrow”.
In a few words, from the abstract: “The subjects were required to respond to one stimulus — an arrow (e.g., →) or a word (e.g., left) — and ignore the other”.
The most important result of the experiment, in brief, is that when the subjects have to act (pressing a key), arrow is stronger than letters, while when the subject have to vocalize the arrow is weaker than letters.
.
Sinsemia 