jspsych-vislexdec

Visual Lexical Decision Experiment (template)

Generic documentation

Please read the generic documentation for some context and scope.

Task Description

The participant first sees a fixation cross, then a word or a non word is presented. Participants are instructed to respond as quickly as possible to make the decision wether the string is a word or not, using the keyboard.

The 'test stimulus' (called 'word') is a string of letters and can be a real word or a nonword.

Crucial trial phases (sub trial phases):

Fixation cross
Visual item (decision phase)

Reference:

      Rubenstein, H., Garfield, L., & Millikan, J.A. (1970). 
      Homographic entries in the internal lexicon. 
      Journal of Verbal Learning and Verbal Behavior, 9, 487≠494.

Output

The data of all (sub) trial phases are logged in the data, but the output data can be filtered after data collection in many ways.
Please read the general primer on jsPsych's data if you are new to jsPsych data output.

Essential output for the 'true experimental' purpose in this template are:

Reaction Time (RT) of the keyboard response in the decision phase
Correctness of the keyboard response in the decision phase

The crucial trial/sub-trial phase (decision phase) output may look similar to this:

	{
		"rt": 700.0000000000073,
		"stimulus": "<p class='stimulus'>thwurp</p>",
		"key_press": 65,
		"condition": "NON_WORD",
		"word": "thwurp",
		"id": 3,
		"trial_phase": "present_word",
		"useful_data_flag": true,
		"correct_response": 0,
		"trial_type": "html-keyboard-response",
		"trial_index": 27,
		"time_elapsed": 45062,
		"internal_node_id": "0.0-11.0-1.4",
		"subject": "8oo722dq",
		"list": "my_one_and_only_list",
		"correct": false,
		"integer_correct": 0,
		"key_chosen_ascii": 65,
		"key_chosen_char": "A",
		"yes_key": "A",
		"no_key": "L"
	},
	//(...)

Variable name (key)	Description	Unit	Type	Comments	jsPsych default	Template default	Plugin name
"rt"	Reaction Time	ms.	float	Reaction time in milliseconds	yes
stimulus"	stimulus (html)		string/html		yes
"key_press"	Keyboard response		string/object?	https://en.wikipedia.org/wiki/ASCII	yes		html-keyboard-response
"condition"	Condition		string	See `stimuli.js`	no	yes
"word"	Decision phase item		string/html	See ```stimuli.js, index.html	no	yes
"id"	ID/code			(...)	yes
"trial_phase"	Trial phase			(...)	no	yes.
"useful_data_flag"	Filter flag		boolean		no	yes
"expected_answer"	TODO change!		todo	Now (still) named "correct_response"	no	no/yes/willbe.
"trial_type"	What plugin was used				yes		"html-keyboard-response"
"trial_index"	jsPsych index				yes
"time_elapsed".	jsPsych time object	ms?	int (/float?)	For instance: 45062	yes
"internal_node_id.	jsPsych node object			For instance:"0.0-11.0-1.4"	yes
"subject"	Subject ID			For instance: "8oo722dq"		yes
"list"	Stimulus list name.		string	For instance: "my_one_and_only_list"	no	yes
"correct"	Scoring result		Boolean	'true or false' score of response		yes
"integer_correct"	Scoring result		integer	1 or 0 for correct or incorrect		yes
"key_chosen_ascii"				For instance: 65	no	yes
"key_chosen_char"				For instance: "A"	no	yes
"yes_key"				For instance: "A"	no	yes
"no_key"				For instance: "L"	no	yes

Getting started

People affiliated with our lab can use the information from our lab webiste and expand the "Online experiments using jsPsych" section for details. Please follow this how-to.

Make your experiment ready for use with the data server

Update access key

In the file globals.js is a variable:

const ACCESS_KEY = '00000000-0000-0000-0000-000000000000';

Before uploading your experimentto the UiL-OTS data server, you will need to change this to the access_key that you obtained when your experiment was approved. For elaborate info see globals.js.

Adapting stimuli

Open the file stimuli.js in your plain text editor.
There is a list, called LIST_1:

const LIST_1 = [ // stimuli and timeline variables

This list can be adapted to your own needs, i.e, you can replace values, make the list longer (don't forget to increment the 'id' values for new items!).
If you need to implement a more complex design, you should read the stimuli.js file (and its comment sections) a little better.
For an example of a Latin square design, please have a look here.

bbonf/jspsych-vislexdec