Table 2.
Demographic statistics.
| Neuropsychological test sample | MRI subsample | |||||
|---|---|---|---|---|---|---|
| n = 125 | n = 65 | |||||
| Women n = 74 | Men n = 51 | Women n = 40 | Men n = 25 | |||
| Mean (SD) | Mean (SD) | t | Mean (SD) | Mean (SD) | t | |
| Age | 71.45 (7.1) | 72.57 (5.8) | −0.97 | 71.20 (6.7) | 72.52 (6.02) | −0.82 |
| Education | 4.65 (3.36) | 8.71 (3.59) | −6.37** | 4.60 (2.9) | 9.00 (3.65) | −5.14** |
| Depressive symptoms | 12.03 (6.19) | 11.75 (6.51) | 0.24 | 12.00 (6.3) | 11.84 (6.18) | 0.10 |
| EVLT index | ||||||
| LTM Recall | 1.66 (0.43) | 1.54 (0.44) | 1.53 | 1.69 (0.44) | 1.64 (0.48) | 0.42 |
| LTM Recognition | 2.35 (0.33) | 2.35 (0.27) | −0.02 | 2.37 (0.29) | 2.38 (0.26) | −0.16 |
| Social network characteristics | ||||||
| Brokerage | 0.57 (0.29) | 0.52 (0.31) | 0.82 | 0.57 (0.29) | 0.48 (0.31) | 1.13 |
| Social network size | 2.24 (1.42) | 2.67 (1.96) | −1.32 | 2.08 (1.23) | 2.64 (1.93) | −1.31 |
| Brain volume | ||||||
| Left hippocampus volume | — | — | 3574.57 (438.85) | 3677.67 (435.88) | −0.93 | |
| Right hippocampus volume | — | — | 3775.54 (454.29) | 3823.036 (478.55) | −0.40 | |
| Intracranial Volume | — | — | 1.23 (0.14) | 1.39 (0.14) | 4.60** | |
Education: years of formal education; Depressive Symptoms: Geriatric Depression Scale total score; EVLT index: Elderly Verbal Learning Test index; LTM: Long-Term Memory; Brokerage: Social network structural constraint (range 0–1), a smaller value indicates a larger opportunity for brokerage; Social Network Size: number of social ties in the global network; Intracranial Volume: Estimated total intracranial volume (/1,000,000 mm3). t = paired sample t-test result indicating a gender difference in variables. **p < 0.001, 2-tailed.