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The He I 1 micron line is a high excitation line which allows us to probe theinnermost regions of protostellar disks, and to trace both accreting andoutflowing material. We use X-Shooter observations of a sample of 107 youngstars in the Lupus (1-3 Myr) and Upper Scorpius (5-10 Myr) star-forming regionsto search for correlations between the line properties, as well as the diskinclination and accretion luminosity. We identified eight distinct profiletypes in the sample. We fitted Gaussian curves to the line features to measurethe maximum velocities traced in absorption, the full-width half-maximum (FWHM)of the line features, and the Gaussian area of the features. We compare theproportion of each profile type in our sample to previous studies in Taurus. Wefind significant variations between Taurus and Lupus in the proportion of PCygni and inverse P Cygni profiles, and between Lupus and Upper Scorpius in thenumber of emission-only and combination profile types. We find that theblue-shifted absorption features appear less blue-shifted at disk inclinationsclose to edge-on, but no such trend with inclination is observed in sourceswith only red-shifted features. Higher accretion rates were observed in sourceswith strong blue-shifted features which, along with the changes in theproportions of each profile type observed in the two regions, indicates thatyounger sources may drive stronger jets or winds. Overall, we observevariations in the proportion of each profile type and in the line propertieswhich indicates and evolution of accretion and ejection signatures over time,and with source properties. These results confirm past works and models of theHe I line, but for a larger sample and for multiple star-forming regions. Thework highlights the power of the He I line as a probe of the gas in theinnermost regions of the disk.

The He I $\lambda$10830 $\AA$ line as a probe of winds and accretion in young stars in Lupus and Upper Scorpius