The first part of my capstone research began with a lit review. I looked for literature in three main areas: the psychology of flow experiences, ergonomics and healthy computing, and task interruption/disruption. I don’t really expect people to read this stuff, and I’m going to be a bad academic and not cite things properly (I will include my bibliography at the end though), mainly I’m writing this as practice for summarizing things for my presentation. Skip to the end of the post for the relevant conclusions I’ve drawn.
The main difficulty I was looking to engage with in my project was the phenomenon of people who know the importance of taking physical breaks and moving frequently during computer use, and have a desire to take better care of themselves and develop better computing habits, but who easily get caught up in their work and fail to take breaks anyway. So I did some preliminary research on flow, that mental state of engagement when one’s skills are well-matched to the difficulty of one’s task. The trouble with flow is that flow is common during work, it’s important to well-being, and deep flow states are quite important to creative work. So flow is a good thing, and I don’t want to create something intrusive that will pull people out of those important deep-flow phases, or be so distracting that they have difficulty reaching a sense of engagement with their work.
In that meeting with Erik Stolterman long ago, (september, I think? A lifetime ago) after we’d settled on encouraging physical breaks from computer work as my problem space, he asked me if I knew what my next steps were. I talked about looking at literature on computer use and ergonomics, and his reaction was “oh, ergonomics, I think that’s a super-boring field.” And let me tell you, he was right.
I looked at ergonomics research anyway, because I wanted research to support my argument that this is an important problem that affects lots of people, and also to understand what kinds of habits are most important to healthy computing.
The most important things I learned from that literature was that while many RSI risks can be reduced through posture and equipment, prolonged static posture alone (in 8+ hours of computer work per day in men, 6+ hours per day in women) is also a risk, regardless of how good your posture is. So, you really do need to get up and move every so often. Along with that, short, frequent breaks are more effective than infrequent, long breaks. Getting up and stretching for a few seconds every 20 minutes or so is important.
I also looked at various sources for RSI prevention tips and collected examples of RSI prevention software. From these I learned that ergonomic specialists recommend a hierarchy of breaks: micropauses, stretch/exercise breaks, and rest breaks. Micropauses should happen once every few minutes and consist of briefly shifting attention and releasing tension. Looking away from the screen every few minutes helps prevent eyestrain. The next is the stretch break, the frequent 20 minute breaks that are so important but difficult to actually do. Many of the RSI prevention programs offer suggestions for quick stretches and exercises during these breaks. Then there are rest breaks, which are longer breaks that give you an opportunity to relax and really get away from your work. This is the activity closest to a traditional conception of a “break.”
This research gave me a framework for understanding what kinds of “breaks” I might try to encourage, and what kinds of activities people should do during them.
Interruption and Disruption
As I said, I want to support computer users’ flow experiences rather than disrupting or preventing them. This led me to some research about workplace interruptions and how people cope with them. The literature on what exactly makes an interruption disruptive (aka, what slows down completion of interrupted task compared to people who were not interrupted) is ambiguous, but interrupting one task to perform a task which requires processing similar material tends to be disruptive, as do complex tasks that require a lot of working memory.
Another thing that happens is that people who are interrupted at their computers tend to go through a “cycle of diversion” once they’ve dealt with the interruption - for example someone working on an Excel file who gets interrupted by an instant message may stop to respond to the message, then cycle through the rest of their open windows, check for other messages, take the opportunity to respond to emails, etc. Some people seem to lose the thread of the original task entirely and work on other things until the process repeats itself. But it turns out that leaving the original task window mostly visible reduces the time people spend on these diversions, compared to situations when dealing with the interruption results in the original task window becoming obscured.
This phase of my research gave me some basis for “don’ts,” things my ultimate design should avoid, in order to minimize its disruptive impact.
So to recap the major insights from this lit review:
- Flow experiences are important to successful and enjoyable work, and deep flow can be so engaging that people lose bodily awareness. I don't want to completely prevent such deep engagement, only minimize the risk that lack of physical activity poses. One of my major design goals is to support users' developing habits that fit into their own working style and don't interfere with their flow experiences.
- Prolonged static posture is a major risk for repetitive stress injuries, and short but frequent movements are the best way to combat this risk. But it mainly becomes a risk after at least 6 hours of largely immobile computer use. So, for example, if you are generally in the habit of getting up and moving regularly, glancing away from your computer screen, and otherwise have a good ergonomic setup, slipping into a deep flow and static posture for a few hours every day is not going to be nearly as risky as spending 6-8 hours a day mostly sitting still.
- Interrupting work to do short, simple things that are unrelated to the interrupted task does not seem to be significantly cognitively disruptive. In a real-world work environment however, moving away from one task can lead to a chain of distractions. An interruption that doesn't change one's working display seems less likely to cause lengthy distractions, having the main task window visible helps people focus
That was not as concise as it should be. Design principle one-liners:
- Uninterrupted deep flow is valuable, don't prevent all deep-flow experiences
- Promote a hierarchical system of breaks, the shorter the break the more frequently it occurs. Someone who successfully follows such a system most of the time is not at risk from infrequent long periods of inactivity.
- To minimize loss of productivity, avoid complex cognitive tasks during breaks and if possible avoid changing the visible workspace.
This is the bulk of the secondary research I did first semester, I’ve done more this semester but have yet to consolidate my notes on individual papers into general overviews, so in the interest of actually finishing this post I’ll stop here.
Blatter, B. M. & Bongers, P. M. (2002). Duration of Computer Use and Mouse Use in Relation to Musculoskeletal Disorders of Neck or Upper Limb. International Journal of Industrial Ergonomics, 30, 295-306.
Carayon, P. & Smith, M. J. (2000). Work Organization and Ergonomics. Applied Ergonomics, 31, 649-662.
Csikszentmihalyi, M. (1990). Flow: The Psychology of Optimal Experience. New York: Harper Perennial.
Csikszentmihalyi, M. (1996). Creativity : Flow and the Psychology of Discovery and
Invention.</em> New York: Harper Perennial.
Gillie, T & Broadbent, D. (1989). What Makes Interruptions Disruptive? A Study of Length, Similarity, and Complexity. Psychological Research, 50, 243-250.
Iqbal, S. T., & Horvitz, E. (2007). Disruption and recovery of computing tasks: field study, analysis, and directions. In Proceedings of the SIGCHI conference on Human factors in computing systems (pp. 677-686). San Jose, California, USA: ACM. doi: 10.1145/1240624.1240730.
Jensen, C. (2003). Development of Neck and Hand-Wrist Symptoms in Relation to Duration of Computer Use at Work. Scandinavian Journal of Work, Environment and Health, 29, 192-205
Jett, Q. R., & George, J. M. (2003). Work Interrupted: A Closer Look at the Role of Interruptions in Organizational Life. The Academy of Management Review, 28(3), 494-507.