Definition of groups I–V and presumed major input to the IO of each group
| Group | IO | Cerebellar cortex | Major input to the IO |
|---|---|---|---|
| I | Subnucleus a of the c-MAO, r-MAO, v-PO except for the caudomedial part, d-PO (lateral and rostral IO) | 1+//1+, 2+//3+, 4+//5+, 5+//6+, 6+//7+ (positive compartments that extend beyond the primary fissure to the anterior lobe) | Mesodiencephalic |
| IIa | Caudal subnucleus c of the c-MAO, β, DMCC, caudal DM, caudomedial v-PO (medial IO) | a+//2+ (VIa, VIII, IX), 2b+//4+ (positive compartments that do not extend beyond the primary fissure but are located in the posterior lobe) | Vestibular |
| IIb | Medial and lateral subnucleus c of the c-MAO (ventrocaudomedial IO) | a+//2+ (VIb–VII), c+//4b+, d+//5a+ (positive compartments that do not extend beyond the primary fissure but are located in the posterior lobe) | Collicular |
| III | Subnucleus b of the c-MAO (ventrocaudal IO) | 1−(med)//1−, 1−(lat)/a−//2−, 2a−//3−,2b−//4b−,c−//4b−,d−//5a−, 3b−//e2− (vermal and central negative compartments) | Somatosensory, vestibular, mesodiencephalic |
| IV | d-DAO, v-DAO, rostral and central DM (rostrodorsal IO) | 2−//4−, b+//f+, b−//f−, 3+//e1+, 3−//e1−, (3b+//e2+), 4−//5−, 5−//6− (negative and lightly positive compartments in the hemisphere and the rostral and caudal pars intermedia) | Somatosensory |
| V | DC and VLO (dorsocaudal IO) | flocculus and lobule X (aldolase C-positive) | Visual |
Refer to Sugihara and Shinoda (2004) for details. See the legend to Fig. 1 for abbreviations.