NeuroTask Scripting

My 7th Script: Advanced Images Demo Experiment Run Experiment

My 7th Script: Advanced Images

howto_user

This is a more complex image task, wherein subjects are shown multiple images at once and click on their favorite.

My 7th Script shows four pairs of images, one pair at a time. For each pair, the subject has to click (or, if using a touchscreen, press) on the image they like more. The subject isn’t told what the common difference between the photos is, but in each pair, one image uses mostly warm colors (e.g., reds, oranges) and the other uses mostly cool colors (e.g., blues, greens). In this example, the experimenter is actually testing whether subjects tend to prefer warm or cool colors. After each click, the subject’s answer is logged as either “warm” or “cool” in the script’s data section. “Block”s are created and used in order to show images in different locations on the screen at the same time (i.e., to manage screen layout.

Topics introduced: blocks, waitfor...or

My First Eight Scripts

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/*Blocks must be created within a box, in this case "main", which is the default
square box that experiments are automatically displayed inside. The first number 
says how far in from the main's left edge to start the block. The second number 
says how far down from main's top edge to start the block. The third number
says how wide to make the block. The fourth says how long to make the block.*/

var n;
var leftblock = main.addblock(5,30,40,40); // Top-left: 5 in, 30 down. 40x40 big.
var rightblock = main.addblock(55,30,40,40); // Top-left: 55 in, 30 down. 40x40 big.

// This time, we preload images inside the block we want to show them in:
leftblock.preload("catcool.png");
rightblock.preload("catwarm.png");
leftblock.preload("officecool.png");
rightblock.preload("officewarm.png");
leftblock.preload("bicyclewarm.png");
rightblock.preload("bicyclecool.png");
leftblock.preload("applewarm.png");
rightblock.preload("applecool.png");
image.await("preloading_completed");

instruction("You will be shown pairs of images. Click the image you prefer.");

/* The "waitfor ... or ..." construct allows more than one thing ("event") to
be an acceptable response that will make the computer move to the next line.
Only the first event to occur will be processed; the rest will be ignored since
the script will have already moved on. This way, once one block (i.e., image)
has been clicked, the other is no longer awaited. Ignore the "i" errors in the 
margin; They only appear because "waitfor" isn't part of normal Javascript.*/

// Pair 1: Cat
leftblock.setimage("catcool.png"); 
rightblock.setimage("catwarm.png");
waitfor
{
    leftblock.await('click');
    n = "cool"; // If this image was clicked, n's value is updated to "cool"
}
or
{
    rightblock.await('click');
    n = "warm"; // If this image was clicked, n's value is updated to "warm"
} 
log(n,"cat"); // Logs current value of n (i.e., "warm" or "cool") as a new line 

// Pair 2: Office
leftblock.setimage("officecool.png");
rightblock.setimage("officewarm.png");
waitfor
{
    leftblock.await('click');
    n = "cool";
}
or
{
    rightblock.await('click');
    n = "warm";
} 
log(n,"office");

// Pair 3: Bicycle
leftblock.setimage("bicyclewarm.png"); 
rightblock.setimage("bicyclecool.png");
waitfor 
{
    leftblock.await('click');
    n = "warm";
}
or
{
    rightblock.await('click');
    n = "cool";
} 
log(n,"office");

// Pair 4: Apple
leftblock.setimage("applewarm.png");
rightblock.setimage("applecool.png");
waitfor
{
    leftblock.await('click');
    n = "warm";
}
or
{
    rightblock.await('click');
    n = "cool";
} 
log(n,"apple");

main.removeblock(leftblock);
main.removeblock(rightblock);

text("Thank you!");
await(2000);
clear();

You can download the files as follows: Click on the file (link) and then right-click and choose Save as... from the menu. Some media files (e.g., sound) will have a download button for this purpose.