Individual average SVV adjustment errors for both the control condition (no visual feedback, in grey) and the test condition (with visual feedback, in black) are plotted against head-roll orientation in all subjects.

<p>The dashed horizontal lines refer to perfect SVV adjustments. While subjects in the first two rows all show a clear decrease in adjustment errors in the visual feedback condition compared to the control condition, subjects in the bottom row had either no A-effect in the control condition or showed no improvement by providing visual feedback.