Learning to Look: Why do some of us Learn to Look at and Understand Visual Information quickly and accurately and Others do not?
Alvin Telser, PhD and Smadar Kedar, PhD
Northwestern University Medical School, Chicago, IL, USA
ABSTRACT
A Web-based online learning program has been developed as a pedagogical tool to assist medical students learn histology. We call this project Digital Analytical Histology (DAH); it is based on a collection of high quality digital images of histology slides, some of which have archival value. It is almost entirely visually based; the interface was conceived as a metaphor for a microscope and mimics the way in which a student uses a microscope. Fields of interest are identified by transparent colored overlays which indicate basic tissue types, organ regions or layers, and notable structures in the field of view. It was developed at Northwestern University, as a collaborative effort between the Medical School and the Academic Technologies division of Information Technology at the University. Version 1 was completed in the fall of 2000, and used successfully by about 170 medical first year students in a core course of the Medical School. This tool aids not only in learning and teaching histology, but also improves learning by focusing on expert analysis rather than simply viewing, examining, or memorizing images. In addition, even without access to a physical microscope, students can view high quality digital images of a collection of histology slides many of which are rare and/or irreplaceable.
1. Statement of the problem:
There are many disciplines in which
students need to learn material that is largely visual in content
(e. g., archeology, art history, various disciplines of medicine). A basic underlying
premise of DAH is the notion that essentially all scientific and clinical knowledge begins
with the observer’s ability to see and interpret something relevant to the subject
under study. There are many challenges to enhancing such learning. Some of the ones we
have addressed are:
2. Description of project:
Digital Analytical Histology is an online archive and Web-based pedagogical tool that provides novel solutions to the above issues. DAH is intended primarily for medical or dental students learning histology. DAH uses a collection of high quality digital images of histology slides many of which are of high archival value.
The concept for the project was developed by Alvin Telser, Ph.D. Initial development was done by Rich Barone and more recently, Smadar Kedar, Ph.D., both members of IT Academic Technologies at Northwestern University, with the aid of student programmers.
The images are based on a collection of microscope slides used in teaching histology to first year medical students at Northwestern. Many of the slides in the collection have assumed an archival value for several reasons: 1) they are made from normal human tissue or from primate tissue which are very difficult to obtain today; 2) they were prepared 50-75 years ago in an era when histology was an active area of biological research, and there was considerable faculty and technical interest and expertise in this area of scholarship; 3) over the years many of these slides have been lost and broken so this rare resource will become unavailable to future generations of medical students.
The images are captured with a high quality light microscope and digital camera. The initial 8 MB images are subjected to minor enhancements in Adobe Photoshop; the many overlays and labels are also done in Photoshop. The images are compressed for the Web with the use of Image Ready; the final size of each image is about 20-30k and is 500 x 372 pixels. This massive reduction in image size does not significantly diminish the quality of the images for the Web at 72 dpi, which enables this collection to be viewed rapidly and at very high image quality by today’s typically very narrow-bandwidth Internet connections.
The interface displaying the images is organized in the same general manner as a histology textbook, where material is organized into chapters that reflect the way histology has been conceptualized for the past century or so. Each image is annotated with transparent overlays that illustrate important histological features. In addition, images may have associated labels, highlighting specific tissues, organ regions, or other notable features. Each physical slide is organized into a set of images, leading from the lowest magnification to higher magnifications through a set of "hotspots". These hotspot areas are selected by the expert histologist as important, so students learn to view the images through expert "eyes". The tool is dynamic, getting its data from an Access 2000 Database, using Cold Fusion 4.5.1. Images can be viewed chapter by chapter, or searched for using a search engine.
In order to populate the database, we built a histology-specific asset management tool. The tool is designed as a collection of "wizards" that walk the user through the addition, modification, or deletion of images and their annotations. This tool allows the instructor, without assistance, to easily and quickly populate a large database of such images and their annotations.
3. Outcome:
This tool aids not only in learning and teaching histology, but also in improving the learning, by focusing on expert analysis rather than simple memorization of images. It does this by drawing the student’s attention to a few key areas of a histological image, and providing higher magnification images of just these relevant areas. The initial reaction from those students who commented on the interface has been very positive; during the main period of introducing the interface to our students (October to December, 2000), the DAH site was in the "Top 10" sites on the Galter Health Sciences Library server.
In addition, even without access to a physical microscope, or the actual collection of archival histology slides, students can view high quality digital images from any location connected to the Internet by using their Web browser. Our Web interface delivers very high quality images compared to the majority of other sites that have attempted to provide similar educational support tools. Furthermore, our interface minimizes the use of text in any format but does provide key descriptive information to the learner. We feel this helps concentrate the attention of the learner on the visual material.
Can we provide an answer to the question posed in the title? Probably not at present, but learners seem to fall into three groups. One group acquires the ability to see and interpret information rather quickly and with considerable ability and accuracy. A second group needs a longer time to acquire this ability and appears to have a lower success rate in demonstrating it. The third and smallest group demonstrates no mastery of the material even at the end of the course. Nonetheless, based on student response, DAH appears to have helped people in the first two groups develop their skill in learning histology. At present, it is not clear that the small number of persons in the third group actually used DAH.
BENEFIT TO PARTICIPANTS ATTENDING SESSION:
The web-based histology learning program I have been developing will be of interest to the SOL/CHES audience because it it is focused on the task facing the beginning learner. It exploits the power of the computer as a learning tool in ways that other media cannot do as well as using the power of the computer to deliver high quality color images over the Internet. It emphasizes an analytical approach to a visual subject matter in contrast to an image recognition/memorization mode of learning. It relies on expert judgement and analysis in guiding the learner to understanding histology.
Alvin Telser, PhD
Cell & Molecular Biology-W 129
Northwestern University Medical School
303 e. Chicago Ave.
Chicago, IL 60611
Phone: 312-503-8276
Fax: 312-503-7912
Email: agt@northwestern.edu
CO-AUTHORS:
Smadar Kedar, PhD
Learning Technologies Group
1935 Sheridan Rd.
Northwestern University Library -2EAST
Evanston, IL 60208-2323
Phone: 847-467-6493
Fax: 847-491-3824
Email: kedar@northwestern.edu