2 PSYCHOLOGY AND INFORMATION TECHNOLOGY? REALLY? Increasingly, professionals and the public recognize that human psychology is an integral part of IT environment. This is because the human mind is the main user and operator of IT systems, as well as all man-­‐machine interfaces in general. For example, the U.S. based Rensselaer Polytechnic Institute that offers education in architecture, engineering, IT and science, now offers an IT and Web Science Program with Concentration in Psychology as a 4 year Bachelor of Science Degree.1 The program requirements include studying general and cognitive psychology, IT and society, human computer interaction, and human factors in design. We believe that nominal knowledge of human cognitive processes is imperative for designing effective and efficient IT systems. Cognitive psychologists seem to agree. Just look at the vast amount of research on the interaction of human psychology and IT.2 The purpose of this paper is to introduce you to a sample of cognitive psychology findings that could play an important role in IT design. The following are examples of some peculiarities or regularities of human cognition that have been studied and documented scientifically. These may serve to improve the effectiveness of IT design if the designers are aware of them. However, if ignored, these regularities may create serious limitations for the effectiveness of IT design. THE SIMON EFFECT The Simon Effect, first studied by Simon (1969), refers to the fact that people are faster and more accurate when responding to an object that is in the same location as the response button that is associated with it.3 For example, imagine that you are asked to press a letter “M” (on the right side of your keyboard) when you see a Green square appear anywhere on a computer screen and press a letter “X” (on the left side of the keyboard) when a Red square appears instead. So, ideally, you should be pressing the “M” button every time you see a Green square, regardless of where the square itself is located on the screen. However, research shows that people tend to make systematic errors when the Green square is located on the opposite side of the screen from where the associated “M” button is located.4 Situation 1 You will be faster and more accurate when the Green square is in the same relative location as the “M” response button that is associated with it (i.e. both are on the right). “X” “M” Situation 2 You will be slower and make more errors (i.e. will press “X” instead of “M”) when the Green square is NOT in the same relative location as the associated button “M.” “X” “M” http://www.rpi.edu/IT/undergraduate/concentrations/fall10/psychology.html http://scholar.google.ca/scholar?q=information+technology+and+psychology&hl=en&as_sdt=0&as_vis=1&oi=scholart http://www.highbeam.com/doc/1G1-­‐16546992.html 3 Vanhorn, D. (2011). Coglab online manual. Belmont, CA: Wadsworth. (p.54) 4 Ibid
1
2
3 The Simon Effect is extremely strong, even when people are aware of it,5 and so it is important to take it into account when designing any man-­‐machine interface. For example, imagine that you are a pilot of a plane and you discover that the right engine has a problem. If the button for the right engine is located on the right and the button for the left engine is located on the left (as they are associated with the corresponding engines in your head), then you’ll be faster and more accurate at pressing the correct button. But if the buttons are located the other way around (i.e. the button for the right engine is located on the left), than you may respond incorrectly and adjust the wrong engine. This can potentially create a serious problem. The same mechanism applies to IT systems design. Take accounting software. As accountants, we are used to debiting amounts on the left side and crediting on the right side. If you design a new accounting software where the “Credit” button is located on the left and “Debit” on the right, than your accountants are doomed to be much slower and/or produce a higher amount of input errors. Intuitive? Yes. Have you ever thought about it? Probably not. PHONOLOGICAL SIMILARITY EFFECT What it means is that people are worse at remembering and distinguishing words when the words sound similarly.6 What is fascinating about the Phonological Similarity Effect is that it occurs even when the information comes through the visual rather that auditory channel, as when you are looking at information instead of hearing it.7 For example, it would seem logical to suppose that when you are reading, you are more likely to confuse items that look similarly (e.g. letters “O” and “Q”). But what really happens is that, when looking at information, you are likely to confuse items that sound the same (e.g. letters “G” and “J”). According to Baddeley (1986), this happens because visual information gets converted into phonological form. 8 What implications does this have for IT systems design? Say you design a new application and you decide to have the following two options for closing a document: Close To close the document without saving, and Shmose To save and close the document. Even though the two words look differently, Phonological Similarity Effect says that you will still be likely to confuse them (and consequently press the wrong button) because they sound similar. This will produce higher rates of error and data loss, and longer processing times, because your accountants will mistakenly be “closing” documents instead of “shmosing” them and the other way around. Therefore, it is strongly recommended that the names or labels that you choose for two different options are as far from each other phonologically as possible (as is most often done in practice already). Trivial? Yes. Unimportant? Never! Ibid Vanhorn, D. (2011). Coglab online manual. Belmont, CA: Wadsworth. (p.71) 7 Ibid 8 Ibid 5
6
4 METACONTRAST MASKING EFFECT Remember how annoying and distracting those internet pop-­‐ups, online advertisements, survey invitations and update reminders on your computer are? Cognitive psychology explains that these distractions have a Metacontrast Masking Effect. It has been scientifically proven that a presentation of one stimulus to your attention can impair your perception (and therefore subsequent processing) of another stimulus.9 What it means for you as a computer user is that these pop-­‐ups distract you from effectively perceiving and processing the important content you are working on, be it your assignment, an online reading, or your audit working papers. Thus, we think that all these distracters should be eliminated when designing IT systems, especially for such professionals as accountants, doctors, teachers, so that the likelihood of unintentional mistakes and errors is reduced. See http://www.angelfire.com/super/badwebs/ for a colorful example of how distracters work. THE STROOP EFFECT Take a look at the following words and name the color of the ink used to print each word really fast. Set 1: Green Red Blue Purple Blue Purple Set 2: Blue Purple Red Green Purple Green You might be surprised that naming the color of the first set of words is easier and quicker than the second. In psychology, this is referred to as the Stroop Effect, first discovered by Stroop (1935).10 This is believed to happen because reading has become highly practiced, especially among college and university graduates, and has become so automatic that it is difficult not to read.11 Color naming, on the other hand, is not so well practiced and automatic. It is more difficult for you to name the colors of the words in Set 2 because your highly practiced reading overrides, and you can’t help but read the words instead of just noting their colors. This has implications for IT systems design. For example, there is a common convention of using the green color for positive dollar balance (i.e. $1,000) and red for negative balance (i.e. (1,000)). This association may have become so automatized that a sudden switch of the colors in the design of a new system can make it prone to increased levels of unintentional errors. Therefore, when you design new software avoid playing with highly practiced functions and common conventions, or your new system may turn out to be less effective than the one you are replacing. Goldstein, E. B. (2011). Cognitive psychology: Connecting mind, research, and everyday experience (3nd Ed). Belmont, CA: Wadsworth (page 79) Vanhorn, D. (2011). Coglab online manual. Belmont, CA: Wadsworth. (p.44) 11 Goldstein, E. B. (2011). Cognitive psychology: Connecting mind, research, and everyday experience (3nd Ed). Belmont, CA: Wadsworth (page 89) 9
10
5 LOCATION-­BASED ATTENTION The concept of location-­‐based attention shows that information processing by humans is more effective at the place where attention is directed.12 This means that finding something situated within the familiar environment is faster. Consider an example of Mac and PC systems. In Windows OS the close red button is at the top right part of the screen, while Mac programs have it at the top left corner. For long-­‐time Windows users who need to transfer to Mac, it might take unnecessarily long to get used to this new layout, since their attention will be directed to the wrong corner of the screen and will slow down the reaction time. We believe that this should be considered when designing new IT systems, especially where accurateness and information processing speed are critical for success. AUTOMATICITY Automatic processing is another concept in cognitive psychology that is important to IT systems design. It is a type of processing that occurs without our intention and at a cost of only some of a person’s cognitive resources. Real-­‐life experiences are filled with examples of automatic processing, because there are many things that have been practiced for years. Most of us carry out such motor skills as typing or using a computer mouse automatically, without attention.13 This has serious implications for systems design. Consider Macs and PCs again. One major difference between two operating systems is that Macs have only one mouse button, instead of two on PCs. Additionally, Command key on Macs is the equivalent of Control key on a PC keyboard, while Macs’ Control key is used in different ways. Imagine how many mistakes may occur when a person transfers from PC to Mac and vice versa. Therefore, automatic processing should be also kept in mind when designing new systems and/or creating updates to existing ones. Functionality and interface should be kept the same, where possible, in order to avoid unintentional errors made automatically due to differences in the layout. CONCLUSION As you can see, these effects are pretty intuitive, common sense you may even say. No doubt. Our point, however, is that these effects have proven to be very robust, even when people are aware of their existence. It is very difficult or practically impossible to control how the human brain works, let alone trying to change it. The take home message for those of you who want to work in IT design: use the knowledge of these human cognition peculiarities to design systems that are easily adaptable, effective and well-­‐accepted by their users. Good luck! 12
Vanhorn, D. (2011). Coglab online manual. Belmont, CA: Wadsworth. (p.48)
13
Goldstein, E. B. (2011). Cognitive psychology: Connecting mind, research, and everyday experience (3nd Ed). Belmont, CA:
Wadsworth (page 92) 6 REFERENCES Goldstein, E. B. (2011). Cognitive psychology: Connecting mind, research, and everyday experience (3nd Ed). Belmont, CA: Wadsworth Vanhorn, D. (2011). Coglab online manual. Belmont, CA: Wadsworth Rensselaer Polytechnic Institute: http://www.rpi.edu/IT/undergraduate/concentrations/fall10/psychology.html Scholarly Articles: http://scholar.google.ca/scholar?q=information+technology+and+psychology&hl=en&as_sdt=0&as_vis=1
&oi=scholart http://www.highbeam.com/doc/1G1-­‐16546992.html