word usage - The meaning of 'where' in "Your secondary mode is external, where you deal with things rationally and logically"

This is a paragraph generally describing the characteristics of an ISTJ person:

As an ISTJ, your primary mode of living is focused internally, where you take things in via your five senses in a literal, concrete fashion. Your secondary mode is external, where you deal with things rationally and logically.

Source: http://www.personalitypage.com/ISTJ.html

I've checked the meaning of the word 'where' in many dictionaries but I couldn't find the correct meaning of that word in this context. For me, I guess 'where' in the paragraph means 'which means', or I can rewrite these sentences like:

As an ISTJ, your primary mode of living is focused internally, which means you take things in via your five senses in a literal, concrete fashion. Your secondary mode is external, which means you deal with things rationally and logically.

Is my guess correct? Could you explain more and give some examples like this?

Answer

Your sentences,

As an ISTJ, your primary mode of living is focused internally, where you take things in via your five senses in a literal, concrete fashion. Your secondary mode is external, where you deal with things rationally and logically.

though still convey a roughly similar idea when those where's being rephrased as which means, the meaning would change. It might be easier to understand your sentences like this:

As an ISTJ, your primary mode of living is focused internally. It's the mode where you take things in via your five senses in a literal, concrete fashion. Your secondary mode is external. It's the mode where you deal with things rationally and logically.

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The word where's in your sentence are used as relative pronouns (also known as subordinate conjunctions). Most grammar books discuss only that, who, whom, which, when it comes to relative pronouns. However, Collins COBUILD English Grammar mentions that when and where can be used as relative pronouns in non-defining relative clauses:

8.104 'When' and 'where' are used in non-defining clauses.

I want to see you at 12 o'clock, when you go to your lunch.
Dan's fondest memory is of last year, when the club gave a tea party for the Queen Mother.
He came from Herne Bay, where Lally had once spent a holiday.
She carried them up the stairs to the art room, where the brushes and paints had been set out.

To make the term "non-defining relative clause" clear, here is how the term is defined in the book, under entry 8.85:

Non-defining relative clauses give further information which is not needed to identify the person, thing, or group you are talking about. For example, if you say 'I saw Kylie Minogue', it is clear who you mean. But you might want to add more information about Kylie Minogue, so you might say, for example, 'I saw Kylie Minogue, who was staying at the hotel opposite'. In this sentence, 'who was staying at the hotel opposite' is a non-defining relative clause.

He was walking to the girl, who was running along the platform.
He walked down to Broadway, the main street of the town, which ran parallel to the river.