Retrogrades in the Natal Horoscope
When Mercury is retrograde, the thought processes are introspective, deliberate and internalized. Before any personal matter can be discussed, it must be processed internally.
This means that, if you want to discuss a personal matter with a Mercury Retrograde friend, you must tell them what you want to discuss and set up an appointment to discuss it. If you want an immediate answer, you will not get an honest or well though out answer. They need time to brood and ponder.
Because these people need to digest and process first, they are slow to defend themselves and slow to respond to queries of a personal nature unless they are prepared ahead of time.
• They appreciate a slow reaction in another.
• They can easily discuss non-personal subjects, their own interests and expertise, without introspection. This has already been done in the past.
On personal subjects, they may not know immediately how they feel about something – they need that brood and ponder time.
Perception is quite good because they are sensitive to how they feel about things; the perceptions are highly individualized.
They prefer a Reflective Analysis. In intellectual matters, they are rarely superficial but they tend to analyze, re-analyze, reflect and then apply internally.
There is a perfectionistic side so they can talk in absolutes – using terms such as “always” and “never.”
Many Mercury retrograde people feel that they had no one to talk to as a child.
The thoughts and mental activity became internalized and highly subjective.
They may be prone to day dream.
Some may be so absorbed in their own internalized thoughts that they seem absent-minded and unaware of external activities. This is especially true if Mercury is retrograde in the cadent (3, 6, 9, 12) Houses. And, especially if aspecting Neptune, a planet that can go off into its own world and lose track of time.
(not my content) source: http://www.lynnkoiner.com/astrology-articles/retrogrades-in-the-natal-horoscope