I'm not sure I buy this. According to their definition I'm a polyglot, but I do not experience this difference in mental effort when speaking or listening. I of

I'm not sure I buy this. According to their definition I'm a polyglot, but I do not experience this difference in mental effort when speaking or listening. I often make jokes crossing two or three different languages, it feels completely natural. My proficiency, however, isn't the same in all of them but that's mainly tied to frequency of use and not lack of knowledge. I think when languages are learnt plays a critical factor in the measurements. If one learns three languages as a young child at the same time, chances are the level of effort is roughly equivalent when speaking or conversing, and the results will be quite distinct from someone else learning different languages at different points in their life.