There have been similar experiments with images and even dreams. But it's not clear to what extent what is learnt from one individual can be used to "decode" someone else's visualizations:
https://www.huffpost.com/entry/reading-dreams-scans_n_3016895
Yes and no.
There are features common to all languages. And there are features that are unique to pretty much every language (or language family). For example all languages have words that are functionally equivalent to verbs, nouns and adjectives. So that probably represents something about the way the brain organises information. But which things are verbs, nouns and adjectives varies enormously between languages. So "hungry" is an adjective in English, a noun in Italian and a verb in Japanese (actually, there isn't a word for it in Japanese but...)
There is something called the Sapir-Whorf(*) hypothesis which suggested that the language people speak controls or limits the things they can think about. But it is not, in general true. So, for example, some languages have fewer words for colours than others but that doesn't mean that, for example, a Japanese person can't tell the difference between blue and green; they just happen to use the same word for both.
However, having words for concepts does make a very slight difference to how the brain processes things. So a common method in psychological tests is to time how long people take for a particular task. And it turns out that in a language that has more words for colours, people are fractionally faster to match the colour of objects. Or in languages where the grammar categorise objects by their shape, then people are fractionally faster to identify shapes. But this is milliseconds and there is probably more variation within a language group than there is between any two people from different language groups.
(*) No, not the Klingon