Fig. (2) Schematic representation of the model of SCs. Section I includes the SC with external radius R, internal radius a and longitude L. Section IIa and b present the two variants of the cupular structure: the cupula as an elastic piston in the form of a cylinder of width 2δ and diameter 2b (shown in IIa), and the cupula as an elastic diaphragm of width 2δ and diameter 2b (shown in IIb). In both cases, the canal rotates with angular velocity ω. P₁ - P₂ represents the pressure difference which develops between the sides of the cupula.