Run an Object Representation & Tracking (ORT) study in Matlab with minimal configuration. This is useful for developmental psychologists who want to examine infants' visual short term memory for objects and features.

Infants are familiarized to two objects hidden behind two occluders. After 5 familiarization trials, they receive 4 test trials: Baseline (BL), Surface Feature (SF), Spatiotemporal (ST), and Feature Binding (FB). These are adapted from Mareschel & Johnson (2003). In each test trial, the occluders are lifted to reveal two objects.

The sessions can be coded online using the keyboard, and all stimuli, timing options, and orders are easily configurable.

• Download ort.m and the example "commfeat" study folder
• Create a folder in your Matlab directory and place these files inside of it
• Add this folder to your list of Matlab paths

• Copy the example study folder, "commfeat", into a subfolder of your main ORT directory
• Modify config.txt with the configuration options for the new study using Excel. Save as a tab-delimited text file.
• Modify the stimuli in the stimuli sub-folder.

• Load Matlab
• Type ort in the command prompt
• Select your new study folder and click "Open"
• Follow on-screen prompts (e.g., enter the experimenter's name, infant's subject code, age, etc.)
• Code the infant's looking using the LeftArrow (for a right look), RightArrow (for a left look), and DownArrow (for a center look). Press the corresponding key when the infant is looking in that direction on the screen, and release the key when the baby stops looking.
• A log for the session will be created in the logs sub-folder
• A session file (with looking time results, participant details, and session metadata) will be created in the sessions sub-folder

All original code written by and copyright (2013), Brock Ferguson. I am a researcher at Northwestern University study infant conceptual development and language acquisition.

You can cite this software using:

Ferguson, B. (2013). Object Representation & Tracking (ORT) for Matlab. Retrieved from https://github.com/brockf/ORT.

This code is completely dependent on the PsychToolbox library for Matlab. You should absolutely cite them if you use this library:

Brainard, D. H. (1997) The Psychophysics Toolbox, Spatial Vision 10:433-436.

Pelli, D. G. (1997) The VideoToolbox software for visual psychophysics: Transforming numbers into movies, Spatial Vision 10:437-442.

Kleiner M, Brainard D, Pelli D, 2007, "What's new in Psychtoolbox-3?" Perception 36 ECVP Abstract Supplement.