While teaching "Laboratory in Cognitive Psychology" at Indiana University, I developed several laboratory experiments to be used on Macintosh computers. I created the experiments out of dissatisfaction with the existing Macintosh demonstration and laboratory software. I have tried to design my packages with the following principles in mind:
· Flexibility. The student should be able to manipulate theoretically important variables in creating their experiment. The experiments are designed to open-ended enough so that genuinely novel experiments can be generated. Science involves creativity as much as methodological rigor, and students should get a chance to exercise creativity in designing their experiments. Thus, rather than being "canned labs," the current experiments allow substantial amounts of exploration.
· Ease of use. Students should not have to learn a programming language in order to design their experiments. Although the experiments have a fair amount of flexibility, this flexibility is usually achieved by simple menu choices and specifying options that appear on a screen. Because students never learn a genuine language for creating experiments, there are certainly constraints on what they can do. At times, these constraints are desireable, because they assure that students will be conducting experiments that are similar enough to each other so as to be relevant.
· Self-Experimentation. The experiments are designed so that students can run themselves as subjects in the experiments. In some of the experiments, the computer is able to randomly generate its own stimuli. In other experiments, the phenomena are sufficiently cognitively impenetetrable (resistant to conscious strategies) that it may not make too much difference whether the student knows what their hypothesis is as they test themselves.
· Generic Psychology Laboratory. This laboratory is designed to run many different kinds of experiments involving words, pictures, and sounds. The pictures and sounds that you want to use in an experiment are stored in one file that can be accessed using the freeware program "Resedit." A second file has a list of all of the trials that you want to expose to a subject. Each trial is made up of one or more displays, and each display describes what will appear, where it will appear, how long it will appear, what the correct response is to it.
· Feature Search. This laboratory allows students to design and run experiments in which subjects must search for target stimuli in a background of distractor elements, as exemplified by research by Triesman, Wolfe, Cohen, Cave, Duncan, among many others. The experiments allows students to test theories of pattern recognition, perceptual identification, memory, search strategies, and decision making. Students can specify the number of distinct target elements, the number of distractors, the color and shape of each element, the total number of elements in a display, and the number of trials.
o Download the manual for this laboratory (Microsoft Word file) This manual includes a description of a special font that was designed to be used with this laboratory.
· Memory. This laboratory runs experiments probing either implicit or explicit memory. Students can either have the computer generate lists of nonsense 3-letter syllables, or they can create their own lists of words. The computer then exposes students to the words and tests their memory for the words via recall, recognition, or perceptual identification testing procedures.
o Download a couple of word lists for use with this laboratory (Microsoft Word files)To download these word lists, you will need a program that can decompress files compressed by Stuffit.
· Concept Learning. This laboratory runs experiments related to concept learning. The visually presented concepts are either composed out of a set of dots or curves. The laboratory is based on concept learning research with dot pattern by Posner and Keele, Homa, Nosofsky, and many others. Students can have the computer generate random concepts, or they can create their own concepts. Students specify how distortions of concept prototypes are created, how many categories are presented, how many items within each category are presented, and how the items appear on the screen.
· Apparent Motion. An illusion of apparent motion is obtained when separate visual "frames" are presented in rapid succession. The laboratory allows students to explore phenomena related to apparent motion by creating their own frames (using Superpaint, or other drawing programs) and then alternating between them on the screen. Students can manipulate the timing of the frames, the blank interval between frames, the order in which frames are exposed, and can actively alter spatial displacements of the frames while they are being shown.
o Download a set of frames that were designed for use with this laboratory To download these pictures/frames, you will need a program that can decompress files compressed by Stuffit.
o If you are using a Powermacintosh or a more recent Macintosh, you should download the updated apparent motion laboratory located here.
· Complex Adaptive Systems. In addition to the above experiments directly related to cognitive psychology, I have also developed a number of simulations of complex adaptive systems. Several of these simulations are somewhat relevant to cognitive psychology, including neural network learning systems, demonstrations of chaotic population growth, motion perception, and genetic algorithms.