Extroverted and Introverted functions are functions that can easily be described as “Outer world” and “Inner world” functions respectively. However, their functionality is a bit more complex than to be so specific. It would be more accurate to say Extroversion correlates with Objectivity, and Introversion correlates with Subjectivity. Extroverted functions focus on something Objective, that is to say: something that is apart from the subject. They are impersonal and reference and objective (sometime external) source. Extroverted functions do not necessarily engage only the “external world”, it is possible for an extroverted function to be abstracted inward while used in tandem with an introverted function. This is actually how introvert usually use their auxiliary extroverted function. For example, Ne perceives objective patterns, and these patterns could possibly be seen within a person’s internal thoughts and feelings. Ne can view the internal analysis or point of view that the person is using, objectively; and thus perceive patterns within one’s own internal thinking or feeling process. Introverted Functions stem from the internal and subjective world. These are all functions that are personal to the person who uses them; it could be their personal logic, convictions, or worldview. They are functions that exist only for the benefit of the person who is using them, and cannot be seen or understood by anyone else, unless translated into something objective by an extroverted function.
The Extroverted type:
Despite popular belief, being an extrovert has nothing to do with how much you talk. Any personality type at all is going to be stimulated by their dominant function, and if their dominant function is an extroverted function, then they are considered an extroverted type. The extroverted type is a personality type that is stimulated (gains energy) by interfacing with a certain element of the external world. This can come in the form of social engagement; however it is not exclusive to this. For instance, Fe is stimulated by the social connection made with other people through social interaction, but Se is stimulated by the sensations of the external world, thus their stimulation could be gained outside of social interaction. The act of extroversion is simply engaging with the external world, this could be in the form of listening to a person speak, being aware of your senses, being aware of the present patterns, or even drawing a picture.
The Introverted type:
A personality type that has an introverted function as a dominant function is an introvert. In other words, it is a personality type that is stimulated by interfacing with the dominant element of their internal world. This however does not mean that an introverted type cannot interface with the external world, it is just draining task for them. This is also not suggesting that an introvert cannot be “talkative”, as the amount a person is talking is not an indicator that they are being stimulated by it, but rather that they are well versed in the activity. It is also possible to use external engagement as a catalyst to stimulate the internal world, if this engagement is allowing the introvert to go back into their internal world, and gain moment come back out for more engagement. For instance, an INTP is a Ti dominant, meaning the social engagement and articulation required to use Fe will be the most draining activity for them. However, if this engagement is in the form of a debate for example, they can use this engagement to go back into their Ti, analyze the information taken from the other person which allows them to be stimulated by its use, and then use this energy gained to articulate their answers; making an overall very stimulating experience for the INTP.