Table 1.

Summary of subject group, postural test conditions, and threshold measures

Study	Subjects	Postural Measures	Threshold Measures
Study A	12 8 females 4 males Mean age 34 yr (SD = 9, range 21–50)	SOT 1: Normal vision, fixed support SOT 2: eyes closed, fixed support SOT 3: sway-referenced vision, fixed support SOT 4: normal vision, sway referenced support SOT 5: eyes closed, sway-referenced support SOT 6: sway-referenced vision, sway-referenced support	Lateral (Y) translation 1 Hz Vertical (Z) translation 1 Hz Yaw rotation 1 Hz Roll tilt 1 Hz Roll tilt 0.2 Hz
Study B	14 8 females 6 males Mean age 39 yr (SD = 12, range 23–61)	Condition 1: eyes open, fixed support Condition 2: eyes closed, fixed support Condition 3: eyes open, foam support Condition 4: eyes closed, foam support	Roll tilt 0.2 Hz Pitch tilt 0.2 Hz LARP tilt 0.2 Hz RALP tilt 0.2 Hz

LARP tilts result from an earth-horizontal head rotation that primarily activates left anterior and right posterior (LARP) canals (i.e., is between pitch and roll). Right anterior left posterior (RALP) tilts result from an earth-horizontal head rotation that primarily activates right anterior and left posterior (RALP) canals. SOT, sensory organization test.