Click the target

Present several images as clickable response options and score the clicked target correctly even when display positions are shuffled.

When to use it

Use this for forced-choice tasks where the stimuli themselves are the answers: picture vocabulary tests, target detection among distractors, or match-to-sample displays. Mapping each picture to a keyboard key adds an arbitrary translation step and caps you at a few well-practised keys, while clicking the picture is direct and works on touch devices. If the options are texts rather than pictures, on-screen buttons are usually the cleaner choice.

Trial file

type	stimFormat	stim1	stim2	stim3	stimOptions	key
test	.jpg	dog	car	chair	random	stim1
test	.jpg	cat	lamp	shoe	random	stim1
test	.jpg	horse	table	phone	random	stim1
test	.jpg	bird	cup	book	random	stim1
test	.jpg	fish	clock	door	random	stim1
test	.jpg	cow	bottle	hat	random	stim1

How it works

Nothing in this file activates clicking explicitly, and that is the point: on a test or practice trial whose keyboard and button1 cells are both empty, and with no responseType set, the images become the clickable response options by default. Each row shows the target (always written in stim1, here the animal) alongside two distractors, and the trial ends when one image is clicked.

A click records the stimulus number as the response, and the clicked file’s name is saved separately in the responseText results column; scoring runs against the number, not the filename. That is why key is written as stim1: it means “the stimulus loaded into slot 1 is the correct answer”.

stimOptions set to random shuffles which display slot each stimulus lands in, so the target appears left, middle or right unpredictably. The stim1 key follows the stimulus through that shuffle, not the screen position, so the dog is scored correct wherever it lands. The order actually shown is saved per trial in the stimOrder_actual results column.

Two silent failure modes to avoid. Filling in keyboard or a button on these rows switches the trial away from click mode, and the images stop being clickable with no warning. And random is matched case-sensitively, so Random shuffles nothing; write it in lowercase exactly.

Variations

• Collect several clicks per trial with min:2;max:4 in responseOptions; a Confirm button appears once the minimum is reached (write the flags without spaces around the colon on click trials).
• Record where on an image the participant clicked by setting responseType to clicks with pixel in responseOptions, or bucket clicks into an invisible grid with grid(3x4).
• Add a confirmation step by combining responseType clicks with a button: the participant selects an image by clicking and commits with the button press.
• Word stimuli work the same way: with stimFormat word and no keyboard, buttons or responseType, the words themselves become the click targets.