Table 4.
Change in VRAM performance measures according to child activity factors*
| N | Latency, seconds (95% CI) | Distance, maze units (95% CI) | Working Memory Count Ratio† (95% CI) | Reference Memory Count Ratio† (95% CI) | |
|---|---|---|---|---|---|
| Books Read per Month | |||||
| Doesn’t read/Rarely | 53 | Ref | Ref | Ref | Ref |
| 1 | 143 | −1 (−14, 11) | 0.1 (−2.0, 2.3) | 0.91 (0.57, 1.45) | 0.92 (0.72, 1.19) |
| 2 | 17 | 1 (−7, 9) | 0.6 (−0.8, 1.9) | 1.07 (0.80, 1.42) | 1.12 (0.96, 1.30) |
| 3+ | 41 | −1 (−11, 8.4) | 0.2 (−1.5, 1.8) | 0.94 (0.66, 1.33) | 1.14 (0.94, 1.37) |
| Duration of Daily Video Game Use | |||||
| Doesn’t play | 28 | Ref | Ref | Ref | Ref |
| Rarely plays | 69 | −8 (−18, 1) | −1.5 (−3.1, 0.2) | 0.76 (0.53, 1.08) | 0.91 (0.76, 1.10) |
| 1 hour/day | 98 | −11 (−20, −2) | −1.7 (−3.3, −0.1) | 0.77 (0.54, 1.08) | 0.84 (0.70, 1.00) |
| 2+ hours/day | 57 | −16 (−25, −6) | −2.4 (−4.1, −0.7) | 0.66 (0.46, 0.95) | 0.79 (0.65, 0.96) |
| Duration of Daily Internet Use | |||||
| Doesn’t surf | 38 | Ref | Ref | Ref | Ref |
| <1 hour/day | 148 | −9 (−16, −1) | −0.8 (−2.1, 0.6) | 0.79 (0.60, 1.06) | 0.89 (0.76, 1.03) |
| 1–2 hours/day | 46 | −7 (−16, 3) | −0.1 (−1.7, 1.5) | 0.89 (0.63, 1.26) | 0.88 (0.73, 1.07) |
| 2+ hours/day | 22 | −12 (−23, 0) | −0.8 (−2.9, 1.2) | 0.93 (0.60, 1.45) | 0.82 (0.64, 1.04) |
| Duration of Daily TV Viewing | |||||
| Rarely | 29 | Ref | Ref | Ref | Ref |
| <1 hour/day | 84 | −4 (−14, 5) | −0.2 (−1.8, 1.5) | 0.95 (0.67, 1.35) | 1.00 (0.83, 1.20) |
| 1–2 hours/day | 87 | −4 (−13, 5) | −0.5 (−2.1, 1.2) | 0.93 (0.66, 1.32) | 0.94 (0.78, 1.14) |
| 2+ hours/day | 54 | −8 (−18, 2) | −0.8 (−2.6, 1.0) | 0.86 (0.59, 1.25) | 0.95 (0.78, 1.16) |
| Frequency of Playing Sports | |||||
| ≤ 2 times/week | 130 | Ref | Ref | Ref | Ref |
| ≥ 3 times/week | 124 | −2 (−8, 3) | −0.2 (−1.2, 0.7) | 0.96 (0.78, 1.17) | 0.98 (0.88, 1.09) |
| Competitive Sports | |||||
| No | 100 | Ref | Ref | Ref | Ref |
| Yes | 112 | −3 (−9, 3) | −0.5 (−1.5, 0.6) | 0.88 (0.70, 1.10) | 0.96 (0.85, 1.09) |
| Previously | 42 | 0 (−8, 8) | 0.1 (−1.3, 1.4) | 0.95 (0.70, 1.27) | 0.94 (0.80, 1.10) |
*
-All models are adjusted for trial (continuous), child age (continuous in years), child sex (males and females), and motion sickness during the test (yes and no).
†
-Count ratios represent the fold-difference in the number of working or reference memory errors relative to the reference group. Ratios >1 indicate more errors, while ratios <1 indicate less errors.
‡
-Bolded estimates are statistically significant (p<0.05). Null values for latency and distance are 0 and 1.0 for working memory and reference memory errors.