Results of the multiple spatial regression analysis conducted to identify synesthesia-relevant ICNs to be included in the FNC analysis
| ICN number | Label of ICNs | Betas | Multiple regression value | ||
|---|---|---|---|---|---|
| Auditory mask | Intraparietal mask | Visual mask | |||
| 1 | Medial visual network | −0.12433 | −0.00555 | 1.81960 | 0.30953 |
| 18 | Auditory network | 3.53987 | 0.01085 | −0.18998 | 0.13207 |
| 12 | Lateral visual network | −0.11789 | −0.01240 | 1.02344 | 0.09962 |
| 16 | Left frontoparietal network | −0.06476 | 1.70691 | −0.05126 | 0.05326 |
| 25 | Lateral parietal network | −0.01792 | 1.06765 | −0.02037 | 0.02193 |
| 19 | Medial parietal network | −0.02189 | 1.07975 | 0.08141 | 0.02109 |
| 21 | Right frontoparietal network | −0.03788 | 1.01988 | −0.03213 | 0.01828 |
| 3 | 0.01709 | 0.03890 | −0.24333 | 0.00560 | |
| — | — | — | — | — | |
| — | — | — | — | — | |
| — | — | — | — | — | |
| 11 | −0.00122 | −0.02028 | −0.01598 | 0.00003 | |
Only components with a beta >1 (bold) on at least one of the three spatial variables were subjected to the FNC analysis to ensure that only ICNs that covered at least one of the synesthesia-relevant brain regions (visual cortex, auditory cortex, and intraparietal cortex) were included. This threshold is represented in the table by the line. Note that already the betas of the next ICN in the table (arbitrarily numbered “3”) are far from the critical value 1, indicating that this and all the other ICNs (with even lower betas) do not contain significant parts of the synesthesia-relevant brain regions.