Division of Environmental Physiology, Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden.
Division of Environmental Physiology, Swedish Aerospace Physiology Center, KTH Royal Institute of Technology, Stockholm, Sweden.
J Neurophysiol. 2024 Nov 1;132(5):1571-1576. doi: 10.1152/jn.00311.2024. Epub 2024 Oct 9.
When entering a coordinated flight turn without visual references, the perception of roll-angular displacement is determined by vestibular cues, and/or probably by assessment of the gravitoinertial (G) load (G magnitude) and its translation into the corresponding bank angle. Herein, we examined whether repeated exposures to hypergravity (G training) in a centrifuge, would advance, not only the ability to accurately assess the G load but also the capacity to detect or estimate the corresponding roll inclination of the centrifuge gondola. To this end, in nine men without piloting experience, the subjective estimation of G load and roll tilt were assessed, in complete darkness, during 5-min coordinated turns in the centrifuge, performed at 1.1 G (25° roll-tilt angle) and 2.0 G (60° roll tilt angle). These trials were conducted before and after 5 wk of G training {3 × 40-min sessions·wk; protocol: 20 × 1 min at G levels close to the individual relaxed G-level tolerance [range: ∼2.6 G (∼67°)-3.6 G (74°)], separated by 1-min intervals at idle speed (1.4 G)}, whereas continual feedback to the subjects was limited to the G load. As expected, G training improved subjects' capacity to assess G load, especially at 2.0 G ( = 0.006). The perception of roll tilt, however, was consistently underestimated (by ∼70%-80%), and not enhanced by G training ( ≥ 0.51). The present findings demonstrate that prolonged repeated G-induced roll-tilts in a centrifuge gondola, while external feedback is restricted to graviception, enhance the capacity to perceive G load, but fail to advance the ability to detect or consciously estimate the magnitude of roll-angular displacement during a coordinated turn. During a coordinated flight turn without external visual references, the pilot typically underestimates the aircraft bank angle, because unreliable information of roll tilt is conveyed by the vestibular system. The present results demonstrate that prolonged repeated gravitoinertial (G)-induced roll-tilts in a centrifuge gondola, while external feedback is restricted to graviception, enhance the capacity to perceive G load, but fail to advance the ability to consciously estimate the magnitude of roll angular displacement.
当在没有视觉参考的情况下进入协调的飞行转弯时，滚转角位移的感知取决于前庭线索，和/或可能取决于对重加惯性（G）负荷（G 大小）的评估及其转化为相应的倾斜角度。在此，我们研究了在离心机中反复暴露于超重力（G 训练）是否不仅会提高准确评估 G 负荷的能力，而且还会提高检测或估计离心机吊舱相应滚转角的能力。为此，在没有飞行经验的 9 名男性中，在完全黑暗的情况下，在离心机中进行 5 分钟的协调转弯时，评估了主观的 G 负荷和滚转角估计，离心机以 1.1 G（25°滚转角）和 2.0 G（60°滚转角）运行。这些试验是在 5 周的 G 训练之前和之后进行的{3×40 分钟/周；方案：在接近个体放松的 G 水平耐受性（范围：2.6 G（67°）-3.6 G（74°））的 G 水平下进行 20×1 分钟，中间间隔 1 分钟，在空速（1.4 G）下休息}，而持续向受试者反馈仅限于 G 负荷。正如预期的那样，G 训练改善了受试者评估 G 负荷的能力，尤其是在 2.0 G（=0.006）时。然而，滚转角的感知始终被低估（约 70％-80％），并且不受 G 训练的影响（≥0.51）。本研究结果表明，在离心机吊舱中反复进行长时间的 G 诱导滚转角倾斜，而外部反馈仅限于重感时，会增强感知 G 负荷的能力，但无法提高在协调转弯过程中检测或有意识地估计滚转角位移的能力。在没有外部视觉参考的协调飞行转弯中，飞行员通常会低估飞机的倾斜角度，因为前庭系统传递的是不可靠的滚转角信息。本研究结果表明，在离心机吊舱中反复进行长时间的重加惯性（G）诱导滚转角倾斜，而外部反馈仅限于重感时，会增强感知 G 负荷的能力，但无法提高在协调转弯过程中检测或有意识地估计滚转角位移的能力。
