These responses are very helpful. Thank you.

@Polarbear: You are right, my son may have an uneven profile and that's precisely why I posted here. My son is so different from any other child I know and I find it difficult to figure out if his various eccentricities are part of being gifted or a sign that he's struggling with something else. This board is so helpful for trying to figure out what looks like normal for kids like ours.

FWIW, my son's WPPSI scores were uneven. The psychologist who administered the exam (for entry into a gifted school) said that my son refused to cooperate with parts of the test, refused to guess and acted silly (blinking excessively and talking in a high pitched voice). She wasn't particularly concerned about the gap in scores but she was concerned about the behavior. She told me that if we didn't see that behavior at school or in everyday life, we should just assume he was anxious and that the scores may not be accurate. A psychologist who has been working with my son for over a year on social skills thinks the test wasn't accurate and that my son was anxious. My son confirmed that he was scared and that the tester seemed angry when he didn't know answers so he stopped cooperating and focused on "cheering her up." I am aware that this anxiety and lack of ability to read the tester and situation may be a sign of some challenge. Or it could be related to the fact that he was a few months shy of five and wasn't ready to sit down and take a test.

I will keep a journal and see if there is a pattern so we can be proactive if there does seem to be a problem. My son spends time with a psychologist every week for social skills. She knows him and doesn't see any cause for concern (she has ruled autism, for example) but she has cautioned that evidence of many learning disabilities only emerge once a child starts school. I imagine it's too early to tell but IF there is some other challenge we aren't aware of, does anything here provide a clue?