Today, one of the our attendings gave a solid overview of the major families of dementias. With the skills of a talented and effective instructor, he queried the audience of residents and students to help him fill out the content of a table designed to help differentiate between the presentations, test findings, and treatments for the different types of diseases. He was able to keep the audience actively engaged and participating, but at one point he asked a question that was met with silence. I volunteered the answer, and he turned to me, somewhat surprised that anyone knew the answer. I explained (that he shouldn’t be so impressed): he had mentioned the answer in a previous talk given several months ago, and I just happened to have a set of notes from that discussion open on my iPad which I was annotating and expanding with the lessons learned from today’s talk.
While it’s not so impressive that I was able to ascertain the answer, impressing someone was not the point for me: the fact is that I had that information and was able to quickly access it, even if it wasn’t readily accessible in my own brain’s memory bank without the assistance of my notes. This raises a major question for lifelong students of medicine: Is it better to try and store as much information in one’s memory as possible knowing that there will be limitations on the amount of information that can be remembered, or is it better to store some (perhaps a large proportion) of that information somewhere it can be easily and quickly referenced? If secondary storage of information is worthwhile, then should clinical information be trusted to a few easily-accessible resources (e.g. a pocketbook, online medical search database) or should it be digested and recorded into a personal notekeeping device (i.e. a notebook)? To approach these questions, we must first understand the nature of knowledge and how it is gained.
The Student’s Dilemma
While we would like to think of knowledge learned as being the truth and that truth is an absolute, for better or worse the learning of medical knowledge is not this simple. Since medicine is based on scientific principles, there is a constant effort to strive for refinement of knowledge towards the best approximation of the truth, but in the mind of a humble scientist there is also the necessary acknowledgment that a better or more truthful explanation may arise to refute his or her prior claim. Simply stated, medical knowledge changes, evolves, and hopefully improves with the advance of medical science. Nonetheless, there is also the knowledge derived from practical experience (or story or wisdom) that enters the learner’s mind in the form of a “gospel” taught by more senior physicians. In many ways, this information is equally important and perhaps carries equal weight because this information is based on direct encounters with individual people that have the full force of a clinician’s mind reviewing the entirety of their unique cases. Nonetheless, something that is gospel must be preached (with strong language, without wavering, and lacking an acknowledgment of uncertainty), and one only has to preach when there are those who do not believe what is being said. In other words, truth does not need to be questioned, but this does not fit the description of anything in medicine. As such, physicians and patients alike must live and function with great uncertainty regarding what is known, what is not known, and whether or not what is “known” is actually meaningful (or “truthful” as charted against a constantly changing measure of what is true).
I will give an example here: I remember either a Neurology attending or fellow once explaining to me that the mild weakness found on ipsilateral limbs in a patient with a unilateral stroke could be explained by involvement of the fibers descending in the anterior corticospinal tract (which travels ipsilaterally and does not cross in the medulla). This descending fiber tract contains somewhere between 10-20% of the corticospinal tract fibers, varies in size between individuals, ends in the thoracic cord, and likely provides innervation to muscles of the neck and upper limbs. Anatomically, this explanation seems to make some sense. I asked another senior Neurology attending this question in a different patient with a similar presentation, and he stated definitively, “It never happens.” In perusing various Neurology textbooks, I cannot find any information corroborating the first explanation. The traditional textbook that most clearly addresses this question, Neurology: A Queen Square Textbook”, states “Of corticospinal fibers, 10% remain uncrossed, their neurones of origin outlining an ipsilateral somatotopic map, a point of little apparent clinical significance.” Why then, does this fiber tract even exist? There are some studies that suggest that the presence of this “accessory” pathway may aid motor recovery from lateral corticospinal tract damage as in stroke  or spinal cord injury .
A common response among learners to these conflicting messages is to give up. The tendency is to lose faith in attempting to achieve the ability to “know.” Accordingly, many choose to defer to those who do “know,” or at least believe they do. The appeal of following guidelines stems from this tendency: in theory, a panel of “experts” have pooled together their knowledge and provided recommendations to follow. In this climate of uncertainty, most people choose to follow. But what makes the experts “experts” in their fields? Often they are the physicians, scientists, or physician-scientists who are pursuing active research or have extensive experience with a particular clinical issue. At best, they are driven in their desire to know by the awareness of the incompleteness and changing nature of knowledge and also by the idealistic hope that it is possible to improve knowledge and thus improve the practice of medicine. Ideally, they additionally generate new evidence to contribute to the current knowledge of disease and treatment in the form of clinical trials, updated reviews, case series, and more. At worst, they may be the ones who are simply preaching the loudest and most forcibly.
I, and many others, would argue that this method of learning and practicing medicine is too passive and not sufficiently adaptive. Consulting (to the exclusion of other sources) searchable databases such as UpToDate potentially leaves one’s mind at the mercy of a few opinionated authors. It is not enough to practice medicine as directed by the Cochrane reviews alone. It is no longer enough to practice medicine based only on the anecdotal and experiential wisdom passed down by prior generations of physicians. And it is largely impractical for any individual physician to stay abreast of the latest developments in every field of medicine, let alone in his or her own field with regards to the numerous studies being published every week. Not surprisingly, it is important, then, to find a balance between all of these sources and types of information and information acquisition.
In my opinion, a notebook is the most essential piece of a physician’s armamentarium. It is more important than the stethoscope, scalpel, or any other tool. Why? The notebook represents a projection of the physician’s mind, and no matter the specialty, the physician’s mind is still his or her greatest asset and most effective tool in treating patients. The notebook serves a number of important roles for the physician:
 Facilitation of memory encoding
A lot of educational theory and research is based on the many ways different individuals learn, particularly with regards to methods emphasizing visual, auditory, and tactile sensation. Incorporating multiple modalities, such as writing notes while listening to a lecture and watching a slide presentation, is thought to improve memory retention. Accordingly, it helps to write down what is learned, whether on the wards, at the white board, during morning report or noon conferences, or at grand rounds or conventions, as this should help you more firmly implant the knowledge into your hippocampi.
 A database of references and the knowledge “family tree” (e.g. lineage)
Because of its origins and the way knowledge works within medicine, the lineage of knowledge remains an important distinction that marks one’s identity as a physician. Since much of medical teaching is based on the experiences of physicians whose careers may last half a dozen or more decades, one’s teachers inspire considerable reverence from the trainees who follow them. However, physicians may encounter several “schools of thought” throughout different stages of training and may find that their own minds are battlegrounds between competing ideologies. Accordingly, I find that it is very important to chart and document from whom one learns a new tenet of medicine (be it a resident, fellow, senior attending, clinical trial, visiting lecturer, clinical trial, review article, textbook, etc.). In the aforementioned example, I cannot remember who asserted to me the notion that damage to the anterior corticospinal tract can result in ipsilateral weakness. As such, I cannot ask him or her how that knowledge was obtained, and it thus holds little water against the assertion of the other attending or my current review of the available literature. If you keep track of your learning and keep references to your sources (e.g. the name of a physician who gave a lecture), it is possible to track how your thinking and understanding of the field evolves over time, particularly when new data is incorporated from new studies or encounters with physicians trained in another school of thought.
 A launchpad for inquiry
Sometimes the hardest thing to remember is a question. And yet, as physicians, questions arise in our minds constantly: much of our role as clinicians mimics the modus operandi of the detective. Furthermore, the ingrained abundance of intellectual curiosity is one of the distinguishing features that differentiates physicians from other health care providers. Nonetheless, our attention is also constantly bombarded by numerous competing interests (pages, e-mail messages, patients and families, other care providers, etc.). There are countless times that I had a question I wanted to ask someone giving a talk which vaporized prior to the talk ending and also numerous occasions when I identified something I wanted to look up which I later forgot about. In order to help further develop your own knowledge base, improve the care of your patients, and perhaps even generate questions that might advance the field as a whole, it helps to write down the questions that come to mind as soon as they arise. This can help identify knowledge areas that you can expand and enrichen, detect problems in your clinical practice that might be useful to address (e.g. Why isn’t there a standardized protocol for (blank) here?), and develop potential ideas for research.
 A map of the mind
Last but not least, the notebook can serve as a measure and organizational tool for the knowledge one has already acquired. Keeping one’s thoughts and memories organized is a very important precursor to developing an easily and quickly accessible knowledge bank. The primary objective is to make your brain an efficient and effective database of knowledge and to use that knowledge to guide actions (e.g. the practice of medicine) in a meaningful way. The notebook should not serve as a replacement for the mind’s memory stores, but rather, it should serve as a visual aid (to trigger memories of learning from direct visualization and also to help guide a mind-only “memory palace”-style search if the notebook is absent) and as a hierarchical “site map” or “table of contents” that helps you keep track of what you know so far and what you don’t know.
I hope I have at least begun to convince you that the notebook and the active engaging and recording of lessons learned are essential for physicians at all levels of training. In my next installment of this series (The Battle for Your Mind), I will discuss different methods modern physcians can use to keep notebooks.
1. Shelton, F, and Reding, MJ. “Effect of Lesion Location on Upper Limb Motor Recovery After Stroke.” Stroke. 2001; 32: 107-112.
2. Priestly, JV. “Promoting anatomical plasticity and recovery of function after traumatic injury to the central or peripheral nervous system.” Brain (2007) 130 (4): 895-897.