We present a ﬁrst investigation about the non-linear ﬂow properties and transient orientational-order ﬂuctuations observed in the shear-thinning lecithin–water–cyclohexanewormlike micellar system at a concentration near to the zero-shear isotropic–nematic phase transition. From rheological measurements the stress plateau was found shifted to very low values of the applied shear rate g_ , compared to most of the concentrated living polymer systemsreported in the literature. Rheo-small angle neutron scattering (Rheo-SANS) experiments performed in the ﬂow-vorticity plane revealed periodical ﬂuctuations of both the order parameter P2 and the angular phi from the vorticity axis as determined from the scattering peaks The periods of the oscillations were not found to depend on imposed g_. A theoretical model was also developed to explain the oscillatory dynamics of the shear-induced nematic order parameter in terms of the presence of standing waves of the director orientation proﬁle along the circumference of the Couette cell. The experimental results of the periodic order parameter ﬂuctuations together with their theoretical modelling shed signiﬁcant new insights on the shear banding phenomenon, particularly its microscopic mechanism.