
Certain elements of the 'inner monologue' could have a visible or otherwise perceivable component. It depends on how the monologue is phrased and how each player decides to interpret it.
There are other components, however, that cannot and should not be perceived by others. These components only exist for flavor or character stablishment or for humor, as some have pointed out.
As a rule of thumb, I do not take inner monologues into account when roleplaying unless it has a direct action attached to it. For example, someone wondering if my character is mad and then frowning. My character can then react to the frowning and she can also interpret, based on the situation, why the frowning happened. If it matches or not what the monologue stablished is a completely different matter.
There are other components, however, that cannot and should not be perceived by others. These components only exist for flavor or character stablishment or for humor, as some have pointed out.
As a rule of thumb, I do not take inner monologues into account when roleplaying unless it has a direct action attached to it. For example, someone wondering if my character is mad and then frowning. My character can then react to the frowning and she can also interpret, based on the situation, why the frowning happened. If it matches or not what the monologue stablished is a completely different matter.