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visual-spatial assessment:

	put on stereo-glasses
	hold 3-button wand
		
	1) Reaction Time Test
		focus on X in middle (flash between task blocks)
		push button when stimulus appears
			stimulus at 6 degrees left or right
			stimulus at 0.5 degrees width
			random intervals from 0.5 to 2.0 sec
			200 trials
				alternate left/right hand
				{ 10, 10, 10, 8*20, 10 }
	
	2) Depth Perception Test
		A) identical object depth alignment with tracker and thumb-button
			placement: fixed-XY
			0 - 5 feet
			10 trials
			
		B) dissimilar object depth alignment with tracker and thumb-button
			placement: fixed-X, head-Y - rand()
			0 - 5 feet
			10 trials
			
		C) vertical bar depth alignment with tracker and thumb-button
			placement: head-X (moves horizontally with head)
			0 - 5 feet
			10 trials
			
	3) Rod and Frame Test

		Orient white bar by rotating wand
		Click LEFT wand button when bar is vertical
			10 trials
			
	4) Eye-Hand Tracking Test

		A) linear task
			nudge ball along line by 'touching' ball with wand.
			reduce size of ball according to distance
				back and forth
				up and down
				repeat x 2
				
		B) circular task
			follow target in 3 axial circles
			
		C) random task
			follow target along meandering path
				increasing speed and unpredictability
			try predictive tracking with highest speed.