You and I are quite genetically similar. Same green eyes, pale skin, deep eye sockets.
If you test your DNA on 23andme, you will find you are roughly 90th percentile Neanderthal DNA or higher.
Neanderthal genes are being heavily selected against since the advent of agriculture. The prevalence of the occipital bun, a key Neanderthal morphological trait, has declined drastically over the course of modern European anthropological history.
The Neanderthals were Ice Age hunters and ill-adapted to an agricultural grain-based diet. You would be well advised to test for 1 week the elimination of inflammatory agents such as refined sugar and wheat.
I have personally observed psychological correlates to deep eye sockets. Namely
1. Honesty, directness, truth compulsion, logic
2. Increased attention span
3. Night owl
4. Obsessive internal monologue
5. Ingenopathic social dysfunction – difficulty socializing with strangers, making small talk, susceptibility to depression, internalization of negative social feedback, especially from close relationships
6. Surface emotional toughness and disassociation
7. Courage stemming from 6, e.g. physical daring, social boldness if not crippled by 5.
Facial morphology develops from the same embryonic stem cells that become the frontal cortex – the “neural crest”. Therefore the face conveys general information about the seat of personality. Neanderthals had exaggerated socket depth, and were small tribe hominids. Neanderthal tribes were much smaller than Homo Sapiens tribes. This suggests that the deep eye socket trait is a marker of adaptation to a small tribe environment, and that people with this trait will have difficulty navigating more fluid, larger social contexts. They will prefer a few stable long-term bonds over shifting alliances and a large, wide, loose social network. E.g., the characteristic introvert who becomes depressed after losing his close circle of friends due to a move, versus the characteristic extrovert who thrives on going out to the bars in a new city and meeting lots of new people.
Of course both introvert and extrovert can become depressed due to a move; this is just one illustration of a difference in processing style. The difference becomes plain over any extended period of observation. Most people fit in the middle, somewhat/sometimes extroverted and somewhat/sometimes introverted. However those on the extremes exhibit a marked bias in one direction. The definition of an introvert need not include handicapped social skills if the general trend of preference/need for small tribe vs large tribe style interaction holds.