[en] The isoscalar spin-spin interaction constant in the quasiparticle-phonon nuclear model (QPM) has been determined from the available experimental data on the isoscalar 1⁺ state (E_x=5.846 MeV) in ²⁰⁸Pb. The isoscalar spin-spin interaction turns out to be weaker than the isovector one by an order of magnitude. The cross sections of (e, e') and (p, p') reactions with the excitation of this 1⁺-state have been calculated. The QPM gives a good description of the behaviour of (e, e')-cross section at q_eff < 1.0 fm^-1 and reproduces absolute value of this cross section with the effective g_s-factors weaker than the g_s-factors for free nucleon by 20%. The description of the (p, p')-angular distribution of 201 MeV photon inelastic scattering is poorer. The absolute value of the calculated (p, p') cross section overestimates the experimental data by a factor of about 1.4. This is consistent with the quenching factor for (e, e') cross section. The interaction with two-phonon configurations influences very weakly the isoscalar 1⁺-level