Cognitive Load and the Emergency Physician
Author: James O’Shea, MD (Assistant Professor of EM, Emory University / Grady Hospital) // Edited by: Alex Koyfman, MD (@EMHighAK, EM Attending Physician, UT Southwestern Medical Center / Parkland Memorial Hospital) & Justin Bright, MD (@JBright2021)
“The greatest weapon against stress is our ability to choose one thought over another.” William James.
This article aims to review cognitive load theory (CLT) as it applies to clinical work in Emergency Medicine (EM). It will introduce key concepts in cognitive load theory, discuss the measurement of cognitive load, and will outline sixteen simple strategies that the working emergency physician can start using today to reduce their cognitive load on shift. These practical strategies will help to free up some of your latent cognitive processing power, allowing you to work more efficiently and with less stress.
You may not know what cognitive load is, but if you work in an Emergency Department (ED) you are probably carrying a ton of it. Cognitive load refers to the total amount of mental effort burdening your working memory at any given time. Working in an ED can involve extremely high cognitive load, and learning to understand and manage it can make you more efficient and less stressed on shift. In the field of ED management, the ED bed is often described as the ‘Million Dollar resource’. If that is true, then the cognitive machinery of the Emergency Physician has to be the ‘Billion Dollar resource’. Ventilators have some complexity and your EMR can hold and manipulate a generous amount of data (when it works) but by far and away the most complex and valuable piece of equipment in the department is resting between your ears. Intuitively you are probably aware of the individualized capacities and limitations of the caffeine-powered intracerebral supercomputer that you expertly operate during your shifts. However, it is important for the working ED physician to understand the cognitive science behind how that well-trained and maintained machinery deals with (or not) the demands of the work that we do.
The mind of the ED physician at work relies heavily on memory. You may already be familiar with the basic Atkinson and Shiffrin (1) model of memory that includes three primary sub-systems (sensory, working, and long-term memory). Sensory information is stored in sensory memory just long enough to be transferred to short-term memory allowing us to retain impressions of sensory information after the original stimulus has ceased. Long-term memory is a nearly unlimited store where retrievability and accessibility constrain use rather than shear capacity. Working memory is different from the other two in that it is severely constrained by a small storage capacity, and yet it is absolutely vital to learning and performing tasks. It is a single limited cognitive resource that we rely on in a work environment with seemingly unlimited demands.
Excessive cognitive load can lead to psychological stress, which may be defined as the state that occurs when the demands of a situation outstrip our perceived ability to cope with it (2). The nature of ED work can often place a cognitive load on physicians that is beyond our innate ability to process, which can result in errors and stress. There has been a growing interest in Emergency Medicine in recent years on personal organizational efficiency, and these strategies often have the effect of reducing the cognitive load on working physicians. We also learn by hard-won experience to ameliorate the excessive demands of our work by employing learned strategies that temporally distributes that load, but it’s hard not to get overburdened sometimes on shift.
In Miller’s (1956) seminal ‘Magic Number’ paper (3) he found that most people can only hold 7 +/- 2 units of information in their working memory at any given time. In contrast to a limited working memory, there is an almost unlimited long-term memory holding cognitive schemas constructed during the learning process and these are the schemas that give rise to expertise. You could think of these schemas as files in your memory holding nodes of learned information such as ‘EKG findings in pericarditis’. In reality, memories are probably distributed in interconnected neural networks but thinking of them as files in a filing cabinet is a helpful image.
In building on Miller’s work, John Sweller developed cognitive load theory (CLT) (4) in the 1980s. CLT was designed to help optimize learning by considering the effect of how information is presented to learners and it’s resulting effect on intellectual performance. As with Miller’s work, it emphasizes the inherent limitations that working memory load places on your ability to process information.
Sweller’s theory goes on to break cognitive load into three subcategories: intrinsic, extraneous and germane cognitive load.
1) Intrinsic cognitive load is the inherent level of difficulty associated with a specific problem and cannot easily be altered. Adding 239.1 + 67.56 is just intrinsically harder than adding 2+2, although it is possible to reduce the cognitive burden of the first equation by breaking it up into steps. Similarly, the dizzy old lady with multiple co-morbidities is just intrinsically more challenging for an Emergency Physician than a young healthy male with bronchitis. That assumes, of course, that the assumption of diagnostic simplicity is not itself the beginning of a cognitive error!
2) Extraneous cognitive load is vital to understand as an Emergency Physician. This load is made up of distractions and unnecessary processing requirements that take up room in your precious, limited and heavily taxed working memory. The goal for the EP is to keep this precious resource clear and available for the type of high-end processing that makes us valuable, such as the initial assessment of a complex patient, the making of clinical decisions and the ability to maintain situational awareness. These situations should not have to compete in real time for processing capacity with thoughts about your house repairs, the latest cat video you watched on YouTube, or even thoughts about non-emergent work items.
3) Germane cognitive load is that load devoted to the processing, construction, and automation of schemas. We construct new schemas in working memory so they can be integrated into existing knowledge in long-term memory. These schemas represent successful learning; they can be retrieved, added to, and used for further problem solving. As our medical expertise expands through clinical experience and training, schemas change so that relevant tasks can be handled more efficiently by working memory. Being an active learner and investing in your knowledge therefore increases your efficiency on shift. CLT as a learning theory is ultimately about diverting cognitive processing power towards this germane cognitive load by reducing the other two.
MEASURING COGNITIVE LOAD
Now for some board prep. Which one of the following is the best way to detect an emergency physician’s cognitive load during a shift?
- An assessment of skin translucency over the MCPs during coffee cup grip.
- When today’s total number of new job searches (completed on shift) is equal to your raw score on the Maslach Burnout Inventory.
- Task-invoked pupillary response.
- Number of complaints currently being filed against you by patients and nurses.
If you have no idea of the answer, circumvent the intrinsic cognitive load of the problem and just pick C! It would be surprising if muscular tension, interpersonal problems and burnout did not correlate with a chronically high level of cognitive load, particularly if it causes psychological stress. However, the evidence shows that greater pupil dilation is associated with high cognitive load and pupil constriction occurs when there is low cognitive load (5,6), implicating stress physiology in our response to demands on working memory. It is also possible to measure cognitive load by examining ‘relative condition efficiency’, which combines subjective ratings of your mental effort and objective performance scores on a given task (7). A third ‘ergonomic’ approach uses the product of your heart rate and blood pressure as an estimate of load (8), which again reminds us that our physiology changes with load, and that there is a physical cost to carrying the cognitive burden of our work.
These measurement tools are helpful for researchers but are not accessible moment to moment on shift. There might be comedy value in having a staring match with yourself holding a make-up mirror at the bedside while trying to take your blood pressure with your free hand, but I think the efforts at measurement would themselves represent unacceptable levels of cognitive load. Therefore, we will focus on management rather than measurement, and hope that increased knowledge of cognitive load theory will bring with it greater self-awareness of its effects.
According to Clark et al (2006) the goal with CLT is to reduce the extraneous load, maximize the germane load, and manage the intrinsic load (9). So how do we convert this knowledge of cognitive load into workable solutions on shift? While the theory was originally developed for educationalists, I believe that it is directly applicable to our work in the ED whether we are teaching, learning ourselves, or just trying to get through the day. In the next section, I will outline 16 simple strategies that the working emergency physician can use to help reduce and manage the cognitive load of our unique work environment.
16 Strategies for Dealing with Cognitive Load
- Take advantage of external memory – use written or typed lists as an extension of your working memory. Patient lists can allow you to track multiple bits of information without the stress of having to hold them in memory. They can be used to track care to disposition and ensure your paperwork is done. Smart EMR design can help here and designers of EMRs could improve systems for EPs by being focused on reducing extraneous load. Frequently EMR programming uses computational steps that make sense from a software design point of view, but may actually involve a shift of processing demand from the software onto the physician’s cognitive processing load. EP’s should be actively involved in EMR design to ensure the software is smart enough to help reduce our cognitive load.
- Minimize interruptions – Be a gatekeeper for your working memory. Just as you triage patients; you must triage the competing extraneous demands on your limited resource. One way is to try to minimize interruptions. Chisholm et al (2000) noted that we are interrupted every 6 minutes and have a ‘break in task’ every nine minutes, with a correlation between these events and number of active patients (10). This can lead to clinical error. Interruptions will inevitably occur, but if necessary politely defer unimportant ones, delegate to a junior or keep a list of started but uncompleted tasks to unload your memory.
- Use simple algorithms on shift – if you can’t write it on the back of a postage stamp, don’t bother, you won’t remember it when it matters. Complexity = increased intrinsic cognitive load.
- Use aids without guilt – An example is the need to remember formulae that you use infrequently, it’s harmful to try. Use an online tool on your phone without guilt because you, my friend, are not looking it up because you can’t remember, you are looking it up because your working memory works in America and loves freedom. Another perfect example of this is the use of the Broselow tape. In children, cognitive load is increased by the unique component of variability of pediatric age and size (11). Remove the load; roll out the tape, turn on the app, or use MDCalc.
- Front load to unload – be an active life-long learner and do your thinking and learning before you need to act or make a decision in the heat of battle. If you work hard off-shift to build schemas into your long-term memory, and pregame difficult decision scenarios, you will use up less processing power when it matters, when your fight or flight physiology is trying to rob you of your ability to use your working memory. Incremental increases in your expertise will help you manage intrinsic load and work more efficiently. This will in turn divert cognitive power towards increasing germane load, helping you to learn from your work.
- Channel your supercomputer – listen to your intuition and answer the questions that it raises, this is the mark of an expert. Most processing is done without your conscious awareness in the interest of mental economy, we just evolved that way (12). That is why we can form impressions within seconds of seeing a patient. Also be aware, that this mental economy leaves us open to error, if things aren’t turning out the way your gut told you they would, reexamine your thinking carefully for common cognitive errors such as anchoring or early closure.
- Reboot before starting – you need an unburdened mind at the start of your shift to prepare for the inevitable torrent. Working in the ED is the cognitive equivalent of taking a drink from a fire hydrant. If you arrive wound up about your taxes or a difficult interpersonal interaction you had an hour before your shift, you are likely to carry that extraneous load into your first patient encounter, and the second… In order to clear my mind, I meditate for at least 5 minutes before every shift (often in my car) and find that it prepares me mentally for the work ahead. http://marc.ucla.edu/mpeg/01_Breathing_Meditation.mp3
- Use ‘When-Then’ and ‘If-Then’ thinking – where possible learn to use decision points in management as triggers, not opportunities for philosophical argument. An example would be Dr. Levitan’s call to use ‘when I can’t intubate or ventilate, then I will cric’. A simpler example would be, ‘if my patient is young and female with abdominal pain, then I will order a urine pregnancy test’. In behavioral psychology this is called ‘The Granny Rule’…’when you pick up all your toys, then you can go and play in the park’.
- Control your patient volume – hard to do I know, but sometimes pushing yourself to take that extra patient when you are stretched can lead to excessive cognitive load, and you, your new patient and your active ones are open to the effects of cognitive error. Eat what’s on your plate before serving yourself more.
- Tune up your equipment – Faith Fitzgerald, a renowned internist was smoking a cigarette in a meeting one day when she reportedly said ‘Frankly guys, wellness bores me’. Many professional athletes report that having to constantly look after their diet and physical training can become tedious. However, they do it so they can perform at a high level. Be an ED athlete; give the job, yourself and your patients the respect you all deserve. Your cognitive equipment relies on a healthy well-perfused body. Turn up well fed, well hydrated, well rested, and having exercised and your mind and shifts will run smoother.
Please see the following source for more info on this aspect: http://health.usnews.com/best-diet/mind-diet
- Use checklists where possible – for the same reason that you use online or physical aids, they free up your mind to think, reduce cognitive load, ensure high standards across changing clinical scenarios and improve patient care (13). A great example is Scott Weingart’s Intubation Checklist (14), (I have no financial interest in Dr. Weingart’s website, and it seems to his great credit neither does he, so we’re all good!).
- Turn up your speakers – it can be helpful to talk and think aloud because group processing is powerful. Do this with your assembled resus team or one-on-one with a trusted colleague. It generates team cohesion, allows for closed-loop communication and avoids error. The decisions are always yours to make, but it’s ok to check your thinking. Learners also appreciate access to how you think, which is often more useful to their educational progression than simple information.
- Learn to breathe – the emotions generated by the intensity and nature of our work are not vapors in the wind, they create physiology, cognition, and influence action. If you are anxious, angry, or trembling like a gun dog then your working memory and motor skills are taken over and unavailable to you. Even in a crowded resuscitation room, you can still discretely take a few tactical breaths, center yourself, connect to your body to anchor yourself in the present moment, broaden your awareness to include the room, and the situation you are in. Then act. Please see the following for more information: http://www.livestrong.com/article/74944-box-breathing-technique
- Close the loop – dispositions free processing capacity and reduce cognitive load, push yourself to close out cases in order to free your mind for the next challenge. Work hard to definitively finish with issues before moving on. As you move around the ED with tasks being fired in your direction you are like an elephant being shot at by little spears. You can keep crashing through the trees with a certain number of spears in your back but eventually if you don’t brush some off you will be brought to your knees.
- Touch it once – If you are working on a chart or any other task, do whatever you can to complete it ideally in one go. This is a well-known efficiency principle that also reduces cognitive load. When I was growing up in Ireland my father and I would repair the stone walls on our farm and he taught me that once you pick up a stone, despite its shape, you should never put it back on the ground, find a spot on the wall for it, otherwise you’ll be picking up the same stone all day and, well…stones are bloody heavy.
- Accept your limits – Unfortunately ‘Subitis Department Hominis’ is not a separate tougher species of human first discovered in a hospital basement 40 years ago, we are just a variant on plain old ‘Homo sapiens’. If you need to alter one of your own schemas due to a hard and surprising clinical experience, give yourself the time and honor to do so, before running headlong into your next patient. The physiological consequences of a stressful clinical encounter are significant and can last for days. This directly affects the working of your cognitive machinery.
BEYOND YOUR OWN COGNITIVE LOAD
We are all unique, and as such, we differ in our cognitive processing capacity. This difference also occurs within ourselves across time as we move from novices to experts. The experience and knowledge that helps us work intuitively from heuristics significantly reduces our cognitive load as we train, and marks out a key difference between the experienced attending and the junior trainee.
Many of us will work directly with residents, medical students or other learners, and they will experience a much higher cognitive load when dealing with problems that you as an expert can complete with hardly a thought. This type of intrinsic load is best dealt with by simple-to-complex ordering of learning tasks and working from a low-to high fidelity environment where possible (15). Interestingly CLT would recommend instruction that de-emphasizes traditional problem-solving, preferring worked examples that provoke the learner to actively explain the problem to themselves. This unburdens the novice learner so that processing can focus on building schemas in long-term memory. The idea is that the learner has to sweat too much to close the gap between the problem and the solution, and much of that load in traditional problem-solving is not devoted to building a retrievable piece of knowledge in long-term memory. The benefit of using more worked examples decreases with increasing expertise, and so the strategies that benefit your intern may be inappropriate for the senior resident.
This reminds us that learners are still constructing the memory schemas that you have already built with hard work and experience during your training. Allow time and support to recognize this reality for them, and for yourself. It is interesting to note that these learned strategies, so vital to our work, find no place in our current model of EM education, and are left to the variable abilities of physicians to put together themselves, which seems to be an important omission in our training.
Communication with ancillary staff and nursing colleagues needs to be clear, collegial, and patient-centered. Clear plans with defined end-points require very little additional cognitive processing. Regular paper or screen rounds with the charge RN can allow problems to be identified and resources to be distributed in ways that avoid sudden surges in demand on your cognitive capacity. Be aware that ED work is a true team sport, and there is a shared team cognitive load that needs careful distribution across members whose cognitive capacity varies, both between individuals and across time.
It is also important to consider the role of cognitive load in our patients. Princeton psychologist Eldar Shafir studies the brain on scarcity and his research group has shown that poverty significantly impedes cognitive function (16). It places a load on our limited cognitive resource that produces what Shafir has termed, ‘bandwidth poverty’. The constant need to focus on what you have a scarcity of, such as money or time, saps your attention and reduces effort. This reduces your ability to make decisions and may be detrimental in the long run.
This is an important fact to remember when providing effective and compassionate care to our patients who struggle with poverty. The demands of being financially stretched, disabled or homeless on a cognitive resource perhaps already limited by drug addiction, physical or mental illness and social isolation is very significant. It also directly affects our personal interactions with patients as we try to process complex social problems. Research has shown that the more cognitive load physicians carry, the more likely they are to allow preformed stereotypes about a patient’s race to influence their opiate prescribing and general medical decision-making (17,18). In addition, the bandwidth poverty described by Shafir’s team could impact our patient’s ability to follow-up with specialists, their primary doctor, or to comply with the advice and medication that we prescribe for them.
COGNITIVE LOAD AND BURNOUT
Many studies have shown that lack of sleep, stress and anxiety negatively affect our cognitive processing capacity and deplete our working memory. Studies of healthcare providers have found that higher levels of acute and chronic stress, fatigue, psychological distress, depression, and burnout are associated with a greater likelihood of making medical errors and providing suboptimal or poorer patient care (18,19,20,21,22,23,24,25).
Each shift can produce ‘bandwidth poverty’ as a consequence of the cognitive load placed on us. The science of scarcity tells us that we may be prone to thinking excessively about what we don’t have, such as adequate personal time, rest from work demands, time to process the things that impact us on shift, or just time to intentionally plan and develop our careers. This response to scarcity then negatively affects our ability to plan and make positive decisions.
The problems our cognitive machinery deals with on shift are often complex and this complexity won’t change. However, the expert deals with complexity quicker and with efficiency because time has been spent training to deal with them. According to Sweller, this intrinsic load can “only be altered by changing the nature of what is learned or by the act of learning itself”(26). In order to reduce intrinsic cognitive load on shift the EP must continually improve their experience, knowledge and skills, so that a difficulty today can be translated into a greater ease tomorrow. Part of this process is incremental and built-in to our training, but a large part of it is also the individual dedication we bring to bear on our reading, thinking and active processing of clinical experience. Work hard today, and you will be unburdened going forward. This is particularly high-yield in our field because of our exposure to repeated cardinal presentations that allow the active learner to build deep complexity over time into their knowledge schema’s of, for example ‘chest pain’, or ‘dizzy elderly female’.
A knowledge of cognitive load theory can help the overburdened emergency physician reduce their cognitive load, free up space in their working memory, and become more effective and less stressed. In this article, I have introduced the concepts of intrinsic, extraneous and germane cognitive load, discussed them in the context of emergency medicine, and outlined sixteen simple strategies that emergency physicians can start using today. The work we do is uniquely challenging, and learning the knowledge and procedural skills to be an emergency physician is only the beginning of understanding how to do our job well. We should routinely seek out and apply knowledge and strategies from other branches of science to aid us in our work, and I believe that these strategies should be incorporated into our practice and the training of emergency medicine residents.
References / Further Reading
- Atkinson RC, Shiffrin RM. (1968). Human Memory: a proposed system and its control processes. In: Kenneth WS, Janet Taylor S, editors. Psychology of Learning and Motivation. New York: Academic Press; pp. 89–195.
- Segerstrom, S. C., & Miller, G. E. (2004). Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry. Psychological Bulletin, 130(4), 601–630.
- Miller, G.A. (1956). “The magic number seven plus or minus two: some limits on our capacity to process information”. Psychological Review 63 (2): 81–97.
- Sweller, J (June 1988). “Cognitive load during problem solving: Effects on learning”. Cognitive Science 12 (2): 257–285.
- Buettner, Ricardo (2013). Cognitive Workload of Humans Using Artificial Intelligence Systems: Towards Objective Measurement Applying Eye-Tracking Technology. KI 2013: 36th German Conference on Artificial Intelligence, September 16-20, 2013, Vol. 8077 of Lecture Notes in Artificial Intelligence (LNAI). Koblenz, Germany: Springer. pp. 37–48.
- Granholm, E. et al (1996). “Pupillary responses index cognitive resource limitations”. Psychophysiology 33 (4): 457–461.
- Paas, F.G.W.C., and Van Merriënboer, J.J.G. (1993). “The efficiency of instructional conditions: An approach to combine mental-effort and performance measures”. Human Factors 35 (4): 737–743.
- Fredericks T.K., Choi S.D., Hart J., Butt S.E., and Mital A. (2005). “An investigation of myocardial aerobic capacity as a measure of both physical and cognitive workloads”. International Journal of Industrial Ergonomics 35 (12): 1097–1107.
- Clark, R. C., Nguyen, F., & Sweller, J. (2006). Efficiency in learning: Evidence-based guidelines to manage cognitive load. San Francisco: Pfeiffer.
- Chisholm, CD, Collison EK, Nelson DR, Cordell WH. (2000). Emergency department workplace interruptions: are emergency physicians “interrupt-driven” and “multitasking”? Acad Emerg Med. Nov;7(11):1239-43.
- Luten R1, Wears RL, Broselow J, Croskerry P, Joseph MM, Frush K. Managing the unique size-related issues of pediatric resuscitation: reducing cognitive load with resuscitation aids. Acad Emerg Med. 2002 Aug;9(8):840-7.
- Gladwell, M. (2005). Blink, The Power of Thinking without Thinking. New York, NY: Little, Brown and Company.
- Gawande, A. (2011) The Checklist Manifesto: How to Get Things Right. Henry Holt and Company.
- Weingart, S. & Hua, A. (2014). An Intubation Checklist for Emergency Department Physicians. ACEP NOW. March ED: Vol 34 – No 3.
- Young, J. & Sewell, J (2015) Applying cognitive load theory to medical education: construct and measurement challenges. Perspect Med Educ. Jun; 4(3): 107–109
- Mani, A, Mullainathan, S., Eldar Shafir, E, Zhao, J. (2013). Poverty Impedes Cognitive Function. Science. 30 Aug 2013: Vol. 341, Issue 6149, pp. 976-980
- Burgess, D. (2010). Are Providers More Likely to Contribute to Healthcare Disparities Under High Levels of Cognitive Load? How Features of the Healthcare Setting May Lead to Biases in Medical Decision Making. Med Decis Making March/April 2010 30: 246-257.
- Burgess et al (2014). The effect of cognitive load and patient race on physicians’ decisions to prescribe opioids for chronic low back pain: a randomized trial. Pain Med. 2014 Jun;15(6):965-74.
- Landrigan CP, Rothschild JM, Cronin JW, et al. (2004).Effect of reducing interns’ work hours on serious medical errors in intensive care units. N Engl J Med; 351:1838–1848.
- West CP, Huschka MM, Novotny PJ, et al. (2006). Association of perceived medical errors with resident distress and empathy: a prospective longitudinal study. JAMA;296:1071–1078.
- Williams ES, Manwell LB, Konrad TR, Linzer M. (2007). The relationship of organizational culture, stress, satisfaction, and burnout with physician-reported error and suboptimal patient care: results from the MEMO study. Health Care Manage Rev;32:203–212.
- Shanafelt T, Bradley K, Wipf J, Back A (2002). Burnout and self-reported patient care in an internal medicine residency program. Ann Intern Med;136:358–367.
- Firth-Cozens J, Greenhalgh J (1997). Doctors’ perceptions of the links between stress and lowered clinical care. Soc Sci Med;44:1017–1022.
- Dugan J, Lauer E, Bouquot Z, Dutro BK, Smith M, Widmeyer G (1996). Stressful nurses: the effect on patient outcomes. J Nurs Care Qual;10:46–58.
- Shirom A, Nirel N, Vinokur AD (2006). Overload, autonomy, and burnout as predictors of physicians’ quality of care. J Occup Health Psychol;11:328–342.
- LeBlanc VR, MacDonald RD, McArthur B, King K, Lepine T. (2005). Paramedic performance in calculating drug dosages following stressful scenarios in a human patient simulator. Prehosp Emerg Care; 9:439–444.
- Van Merriënboer JJ, Sweller J. (2010) Cognitive load theory in health professional education: design principles and strategies. Med Educ. 2010 Jan;44(1):85-93.