Single actomyosin motor interactions in skeletal muscle

► Intensity fluctuations in two polarization selective detection channels. ► The ability to interact using different orientations of the reporter dipole on actin. ► During contraction, bimodal Gaussian photon distributions were observed above rigor noise. ► Clusters of polarized photons indicated an anisotropy decay of 9 s during contraction. ► The slow relaxation dynamics revealed molecular memory.