Alien crystal growth

Please read these instructions carefully. You will be quizzed on their content before the experiment begins.

In this HIT, you will complete a series of 13 trials. Each trial introduces a new type of "alien crystal" that has infected a surface. The crystal has been growing for some time, and your task is to demonstrate what it will look like as it continues to grow. An example crystal is shown below.

You can roll your mouse over an image to "zoom" (Please try it now!). This is necessary for certain crystals with intricate detail.

Before infection

→

After infection

What do you think the crystal will look like if you let it grow longer?
Please use the interactive display below to demonstrate how the crystal will grow.

How to use the interface (please try each function):

Roll over a line segment to highlight it.
If green, the segment will sprout a growth when clicked (it becomes activated).
If red, the segment will return to its deactivated state when clicked.
As a short cut, click the "All" button to activate every segment.
As a short cut, click the "None" button to deactivate every segment.

You can choose as many segments as you see appropriate. The order in which you activate/deactivate segments does not matter, only the finished product matters.

You will not receive any feedback after each trial. The task may feel difficult but please try to choose the best answer.

Instructions