fig5

Figure 5. Summary of the cortico-brainstem-spinal cord system involved in bipedal posture-gait control. (A) The PFC is involved in the planning of goal-directed behaviors. The planning signals are issued via the where and how pathways to eye movement-related areas, such as the SEF and FEF, and PMC, including the PMd and SMA, respectively; (B) The PMC contributes to motor programming; (C). The parietotemporal cortex integrates sensory signals to generate “self-body and space perception.” This cognitive information is carried via the parietal-prefrontal (where) and parieto-premotor (how) pathways; (D) The SEF and FEF (eye movement-related areas) contribute to gaze alignment and postural orientation; (E) The corticofugal projections, such as the cortico-vestibular (Ea), cortico-reticular (Eb), and cortico-tectal projections, to the posture-gait-related areas in the brainstem, activate brainstem-spinal cord pathways (RST, TST, and VST) to achieve biped posture-gait control; (F and G) The primary motor cortex (M1) (F) issues motor commands to the brainstem and spinal cord via the lateral CST. Please look at the text for detailed explanations. PFC: Prefrontal cortex; SEF: supplementary eye field; FEF: frontal eye field; PMC: premotor cortices; PMd: dorsal premotor area; SMA: supplementary motor area; RST: reticulospinal tract; TST: tectospinal tract; VST: vestibulospinal tract; CST: corticospinal tract.