Table 3.
Hypothesis II: Head, intracranial, brain volumes, and GMand WM changes.
| Measurement | Nationality | Age | Nationality × Age | Gender | |
|---|---|---|---|---|---|
| Figures 3A,B | MRI head volume | F(1) = 9.21** | F(8) = 4.00* | F(8) = 3.92*** | F(1) = 9.21** |
| Overall US > CN but depends on age | Overall increase as age | US develops more dramatically than CN; CN >US before 11, US> CN after 11. | Overall Male >Female | ||
| Figures 3C,D | Intracranial volume | F(1) = 12.26*** | F(8) = 3.73*** | F(1) = 9.05** | |
| Overall CN>US between 9 and 15 | CN: inverted U peaking by 10 US: did not reveal a specific pattern. | Overall Male > Female | |||
| Figures 4A,B | Total brain volume | F(1) = 29.49*** | F(8) = 2.52* | F(1) = 8.88** | |
| CN > US who finally caught up by 16 | Inverted U for CN and US, but peaking earlier for CN. | Male > Female, especially for US | |||
| Figures 4C,D | Total GM volume | F(1) = 6.67** | F(8) = 9.24*** | F(8) = 2.98** | |
| Overall CN > US | Overall decrease for CN and US | Inverted U for CN and US, but peaking earlier for US. US > CN before 10, CN > US after 10 | |||
| Figures 4E,F | Total WM volume | F(8) = 5.36*** | F(8) = 3.97*** | F(1) = 5.18* | |
| Overall increase for both CN and US | CN>US before 10, US>CN after 10 | Male > Female for CN after 10 | |||
| Figures 5A,B | Cortex GM | F(1) = 42.79*** | F(8) = 7.57*** | F(8) = 2.06* | |
| CN > US | Overall decrease for both CN and US | Inverted U for CN and US, but peaking earlier for US. | |||
| Figures 5C,D | Cortex WM | F(1) = 25.06*** | F(8) = 6.20*** | F(8) = 6.10*** | |
| US > CN after 13 | Overall increase for both CN and US | US > CN after 13, and develops more dramatically |
Significant level:
*
p < 0.05;
**
p < 0.01;
***
p < 0.001;
empty cell refers to non-significant results.