Article Figures & Data
Figures
- Figure 1.
Box plots depicting the behavior of the subjects for each group. Left, Scores achieved by the subjects in the four statistically significant neuropsychological tests. Right, Connectivity values for the subjects in the five statistically significant links. *p < 0.05, **p < 0.001.
- Figure 2.
Cortical areas implied in the five connectivity links that showed significant differences between groups. A, Different views of the brain based on the MNI template and Harvard–Oxford cortical areas involved in those links. B, Relation of areas, numbers, and colors. C, Significant connectivity links established between those areas.
Tables
sMCI patients (n = 30) pMCI patients (n = 19) p values Age (years) 74.0 ± 5.3 76.7 ± 5.3 0.104 Gender (males/females) 14/16 8/11 0.777 Educational level 2.8 ± 1.3 2.7 ± 1.0 0.934 MMSE score 27.9 ± 1.9 27.4 ± 2.0 0.455 GDS 3.0 ± 0.0 3.0 ± 0.0 1.000 FAQ 1.9 ± 1.8 1.8 ± 2.8 0.501 GDS-SF 3.8 ± 3.1 3.5 ± 3.8 0.647 Immediate recall 20.7 ± 8.2 10.0 ± 5.0 3.26 × 10−6* Delayed recall 8.6 ± 7.4 1.8 ± 2.2 7.18 × 10−5* Rule shift cards 2.4 ± 1.3 1.6 ± 1.2 0.028* Semantic fluency 13.0 ± 2.8 11.6 ± 4.4 0.041* Phonemic fluency 10.8 ± 4.2 8.8 ± 4.1 0.119 BNT 50.4 ± 10.7 46.3 ± 9.4 0.510 Clock drawing test (copy) 7.6 ± 2.6 8.0 ± 4.2 0.600 Clock drawing test (order) 6.4 ± 2.6 7.4 ± 3.6 0.615 Direct digit spam 6.7 ± 1.6 6.4 ± 1.5 0.413 Inverse digit spam 4.7 ± 1.3 4.0 ± 1.4 0.103 VOSP 6.7 ± 3.5 7.2 ± 3.1 0.593 TMTA (time) 78.7 ± 36.0 82.8 ± 33.6 0.580 TMTA (accuracy) 24.0 ± 0.6 23.8 ± 1.8 0.401 TMTB (time) 223.2 ± 107.8 258.4 ± 121.7 0.329 TMTB (accuracy) 20.1 ± 4.8 15.2 ± 8.6 0.050 Ideomotor praxis 7.3 ± 1.7 7.2 ± 1.1 0.374 Left hippocampal volume 0.002217 ± 0.000508 0.001992 ± 0.000254 0.056 Right hippocampal volume 0.002197 ± 0.000466 0.001965 ± 0.000388 0.063 Left entorhinal volume 0.000527 ± 0.000100 0.000452 ± 0.000106 0.038* Right entorhinal volume 0.000481 ± 0.000072 0.000452 ± 0.000155 0.954 Left parahippocampal volume 0.000663 ± 0.000072 0.000596 ± 0.000169 0.153 Right parahippocampal volume 0.000645 ± 0.000113 0.000604 ± 0.000175 0.864 ↵Mean ± SD values of the demographic and clinical characteristics of the sMCI and pMCI patients. MMSE, Mini Mental State Examination; GDS, Global Deterioration Scale; FAQ, Functional Activity Questionnaire; GDS-SF, Geriatric Depression Scale-Short Form; BNT, Boston Naming Test; VOSP, Visual Object and Space Perception Battery; TMTA, Trail-Making Test part A; TMTB, Trail-Making Test part B. Educational level was grouped into five levels: 1, illiterate; 2, primary studies; 3, elemental studies; 4, high school studies; 5, university studies. p values for between-groups differences were introduced, and *p < 0.05. Wilcoxon–Mann–Whitney test was used for continuous variables (age, educational level, MMSE, or immediate and delayed recall) and Fisher's exact test for gender differences.
- Table 2.
The five significant links in the alpha band between sMCI and pMCI patients were obtained with a Mann–Whitney U test after the FDR
sMCI patients (n = 30) pMCI patients (n = 19) p values Classification statistics (%) ACC (95% CI) SEN SPE PPV NPV Link 1 0.11 ± 0.03 0.14 ± 0.02 2.04 × 10−4 77.6 (63.4–88.2) 78.9 76.7 68.2 85.2 Link 2 0.10 ± 0.03 0.14 ± 0.03 3.40 × 10−5 81.6 (68.0–91.2) 84.2 80.0 72.7 88.9 Link 3 0.10 ± 0.02 0.13 ± 0.03 1.73 × 10−4 77.6 (63.4–88.2) 73.7 80.0 70.0 82.8 Link 4 0.14 ± 0.03 0.18 ± 0.03 1.35 × 10−4 77.6 (63.4–88.2) 78.9 76.7 68.2 85.2 Link 5 0.10 ± 0.03 0.14 ± 0.03 2.81 × 10−4 69.4 (54.6–81.7) 68.4 70.0 59.1 77.8 Link 1, right cingulate gyrus, anterior division, with right middle temporal gyrus, temporo-occipital part; Link 2, right cingulate gyrus, anterior division, with right lateral occipital cortex, inferior division; Link 3, right cingulate gyrus, anterior division, with right occipital pole; Link 4, right cingulate gyrus, anterior division, with left supracalcarine cortex; Link 5, right cingulate gyrus, anterior division, with left lateral occipital cortex, inferior division; ACC, accuracy; SEN, sensitivity; SPE, specificity; PPV, positive predictive value; NPV, negative predictive value; 95% CI, 95% confidence interval.
- Table 3.
Spearman's correlation analyses of the five significant links obtained in the alpha band with neuropsychological test scores and hippocampal volumes in the whole sample
Link 1 Link 2 Link 3 Link 4 Link 5 MMSE r = −0.195 r = −0.300 r = −0.207 r = −0.143 r = −0.097 n.s. p = 0.047 n.s. n.s. n.s. Immediate recall r = −0.268 r = −0.394 r = −0.366 r = −0.300 r = −0.350 n.s. p = 0.005 p = 0.010 p = 0.036 p = 0.014 Semantic fluency r = −0.172 r = −0.286 r = −0.264 r = −0.145 r = −0.135 n.s. p = 0.047 n.s. n.s. n.s. Left hippocampal volume r = −0.322 r = −0.370 r = −0.170 r = −0.336 r = −0.213 p = 0.046 p = 0.020 n.s. p = 0.036 n.s. Right hippocampal volume r = −0.223 r = −0.302 r = −0.342 r = −0.368 r = −0.431 n.s. n.s. p = 0.033 p = 0.021 p = 0.006 Left entorhinal volume r = −0.374 r = −0.411 r = −0.209 r = −0.475 r = −0.318 p = 0.021 p = 0.010 n.s. p = 0.003 n.s. Shown are the r (correlation index) and p values that were significant (p < 0.05). MMSE, Mini Mental State Examination.
