# Instructions ### Stimuli The experimental stimuli were implemented in Matlab using Psychtoolbox to render graphics. The code requires Psychtoolbox to be installed and working (www.psychtoolbox.org). The code uses a custom experiment control toolbox (ptbCorgi: https://github.com/aleslab/psychtoolboxProjects). The archived code here is the code as it was used to collect the experiment data (Psychtoolbox 3.0.12, ptbCorgi v0.31.0). If you wish to change/extend the code, use the newest versions of both Psychtoolbox and ptbCorgi. **To run the experiment:** - Make sure Psychtoolbox is installed and working (www.psychtoolbox.org) - In the 'Files' section, select the GitHub component and click to download the 'experimentCode' as a zip - Extract the zip file. - Open matlab and navigate to the extracted code and run: - `setupPsychMasterPath()` - setupPsychMasterPath() will add all the required directories to the matlab path - Next in matlab run: - `psychMaster()` - A GUI will open and within the GUI, click 'Choose Paradigm'. This will allow you to choose a condition to run - Go to github-archive->psychMaster->paradigmFiles. Here there is a folder called 'Training_Conditions' containing the 5 screening condition files: - driftGrating_fast_feedback = training condition used for the speed change discrimination task with a drifting grating stimulus and audio feedback on responses - driftGrating_fast = training condition used for the speed change discrimination task with a drifting grating stimulus and no audio feedback on responses - MoveLine_CRS_lateral_Fast = training condition used for the speed change discrimination task with two lines moving from left to right at a constant retinal speed - Screening_SpeedDisc_fixed_distance = training condition used for the speed discrimination task using two looming lines with fixed distance (variable speed and duration) - Screening_SpeedDisc_fixed_duration = training condition used for the speed discrimination task using two looming lines with fixed duration (variable speed and distance) - There is another folder called 'Main_Experimental_Conditions' containing the 3 main experimental conditions: - SpeedDisc_fixed_distance = Duration speed discrimination condition - SpeedDisc_fixed_duration = Distance speed discrimination condition - MoveLine_accelerating_looming_midspeed = Speed only speed change discrimination condition - There are then also several other files for different conditions used in this experiment. These were used when attempting to compare preferred cue usage for speed change discrimination with motion in depth: - MoveLine_accelerating_depth_midspeed = A combined cue condition containing monocular and binocular cues to motion in depth. Used “fast” speeds. - MoveLine_accelerating_depth_slow = A combined cue condition containing monocular and binocular cues to motion in depth. Used “slow” speeds. - MoveLine_accelerating_cd_midspeed = A condition containing only binocular cues to motion in depth. Used “fast” speeds. - MoveLine_accelerating_cd_slow = A condition containing only binocular cues to motion in depth. Used “slow” speeds. - MoveLine_accelerating_looming_slow = A condition containing only monocular (looming) cues to motion in depth, like the Speed only condition. The Speed only condition used “fast” speeds, while this condition used “slow” speeds. - Choose one of the paradigm files to open. The GUI will then give a list of the levels in the condition - Click "Run Experiment" to run one block of your selected condition, or click "Test Condition" to run 1 single trial of the selected condition. If no response is given in the "Test Condition" mode, the selected condition will continue to run in a loop. - To indicate which interval changed speed, press 'f' for the first interval or 'j' for the second interval when a box appears around the fixation cross. Alternatively, the space bar can be pressed to pause the experiment, and 'esc' can be used to close the experiment early. Viewing distance is set as 97cm in the `moveLineDefaultSettings.m` file located in the paradigmFiles directory. Viewing distance and other settings can be modified there. ### Data and Analysis The original raw data is included in Speed_change_disc_data.zip (Speed only condition) and Speed_disc_data.zip (Distance and Duration conditions). Summary data is in Speed_change_psychometric_outputs.zip (Speed only condition) and Speed_disc_psychometric_outputs.zip (Distance and Duration conditions). Speed change discrimination data from participant Q was excluded from final analysis. The psychometric data analysis was done using the Palamedes toolbox (http://www.palamedestoolbox.org). **To run the analysis:** - Download and install the Palamedes toolbox (http://www.palamedestoolbox.org) - Download Speed_change_disc_data.zip and Speed_disc_data.zip and extract the data to a folder of your choice - The analysis code is in the 'Analysis' directory of the code. - Run: - `MoveLinePsychometricAnalysis` - Select the folder containing the raw data - The code will fit psychometric functions to the data and create plots of the data and psychometric fits. The raw data files contain 2 structures `sessionInfo` and `experimentData`. **sessionInfo** This contains information about the Matlab environment during a data collection session. **sessionDate**: Output of now() when session run. **psychMasterVer**: ptbCorgi version string. **ptbVersion**: Output of PsychtoolboxVersion(). **randomSeed**: Seed used for random number generation, gitHash: SHA1 hash uniquely identifying code version in git. **paradigmFile**: Filename used for paradigm settings **paradigmPath**: Directory paradigm file loaded from. **paradigmFun**: Function handled used to create paradigm settings. **participantID**: String for participant. **returnToGui**: Internal variable. **userCancelled**: Internal variable. **expInfo**: Structure containing various settings for rendering/calibrating the stimuli. **conditionInfo**: Structure (nConditionsx1) containing the parameters and specification for each condition shown to participant. **mfileBackup**: Backup of all custom code used at the time experiment was run. **diary**: Entire output of matlab command window during session. **experimentData** This is a structure containing data collected from the participant. There is 1 element per trial. In order of the trials shown to the participant. It contains the fields: **validTrial**: Boolean set to TRUE if the trial is valid (i.e. participant pressed allowed button within reasonable time). **chosenInterval**: Which interval did participant choose? **isResponseCorrect**: Boolean set to TRUE if particpant chose correctly. **condNumber**: Index into the conditionInfo structure identifying which condition was shown on this trial. **trialData**: Structure containing raw output of trial function