Drop a labelled diagram into Lexie and it finds every label, hides it, and turns the picture into image occlusion flashcards. Drop in a whole PDF and it does the same for every labelled figure in it. All that is left for you is the part that counts, which is typing each label from memory. It works in the browser and in the app, and you do not need Anki for any of it.
The slow part of image occlusion is drawing the boxes
Image occlusion is one of the best ways to learn a diagram. You cover the labels, try to recall each part, and then check yourself. Medical students have relied on it for years, mostly inside Anki.
There is nothing wrong with the method. What wears people down is making the cards. Every label needs its own box, drawn by hand, and a single anatomy figure can easily carry 15 or 20 of them. By the time you have done that for eight figures you have drawn more than a hundred boxes, and the evening you set aside for studying has gone into data entry.
That is the part that image occlusion in Lexie takes over. It reads the picture, works out where each label sits, and hides them for you.
From a picture to hidden labels in eight seconds. Nobody drew a box.
How to make image occlusion flashcards automatically
Getting from a picture to a finished set takes about a minute. You can follow along with your own diagram on the image occlusion page, where a live demo is waiting at the top.
Get the diagrams
One image of a diagram, a few images at once, or a whole PDF. The diagrams need text labels. Your own labelled sketch works too.
Drop them into Lexie
Lexie finds every labelled figure, cuts it away from the text around it, reads each label along with its position, and hides them all.
Check the labels
The pencil opens the label list, where you can correct a label that was read wrong or remove something that is not a label, like a title or a page number.
Type each label from memory
Hide one label at a time or all of them at once. Lexie checks what you type and keeps track of the labels you missed, so you can come back to those.
A whole PDF at once
Most diagrams do not come one at a time. They sit in a PDF, between pages of text. You can drop the whole file into Lexie in the browser. Lexie looks at every page, finds each labelled figure, and makes one card for each. A page of plain text is left out of the cards.
You get one study set, not one set for each figure. The figures are under Label the diagram, in the order they appear in the PDF, and a menu at the top lets you jump to any of them. The text of the PDF goes into the same set as flashcards and a quiz. If a PDF holds only diagrams, the set opens straight into the first one.
Now and then Lexie reads something as a figure that is not one, like a small picture with a title on it. Open the pencil on that card and remove it.
For Anki users who are tired of manual occlusion
If image occlusion in Anki works for you, there is no reason to leave it. This page is for the people who like the method but gave up somewhere around the fortieth box.
Lexie is a separate tool, not an add-on, so there is nothing to install and no deck to set up. You drop in the picture and the test starts. The cards stay in Lexie and cannot be exported to Anki, which is why many students keep Anki for their text cards and bring only their diagrams here. The diagrams are where the setup time goes, and a whole PDF of them takes Lexie about a minute.
The review feels different too. Anki shows you the answer and asks you to grade yourself, while Lexie asks you to type the label before it shows anything. That is a stricter test, and a more honest one, because if you can type it, you know it.
Why image occlusion beats plain flashcards for diagrams
A text card can ask what the mitral valve does, but it cannot ask where it is. In anatomy, cell biology, histology and geography the exam puts a picture in front of you, and knowing where a structure sits is half of the answer.
That is what an image occlusion card tests. Because the hidden label sits on the diagram itself, every time you recall the name you also tie it to the place. It helps to start with Hide one, so that the other labels give you some context, and to move to Hide all once most of them come easily, because that is what the exam will look like.
What you get
No boxes to draw
Lexie finds and hides every text label on the picture for you.
Typed recall
You type the label before you see it, which tests recall and not just recognition.
Hide one or hide all
Keep the other labels visible for context, or hide them all as the exam does.
Labels you can fix
Correct a label or remove a region before you start, in a few seconds.
Photos, images and PDFs
A photo, an image file or a hand-drawn sketch works. A PDF with ten diagrams gives one set with ten cards.
Browser and app
Start on lexielearn.com and carry on in the iOS or Android app.
What it does not do
A few limits are worth knowing before you start. A whole PDF works in the browser. In the app you still take one photo for each diagram. Lexie hides text labels, which means that a structure with no label on the picture cannot be hidden, and a figure without text labels does not become a card. A PDF can be up to 10 MB. And the cards cannot be exported to Anki.
They are flashcards made from a picture. The labels of a diagram are hidden, and each card asks you to recall what sits under one of them. It is the standard way to learn labelled figures in anatomy, biology and geography.
Lexie reads the text in the picture along with the position of each word, groups the words into labels, and hides them. Before you start you can correct a label or remove one.
No. Lexie is its own tool, and it runs in the browser and in the iOS and Android app with nothing to install.
No, the cards stay in Lexie. If you want everything in one Anki schedule, Anki is still the place to make them.
Yes, in the browser. Lexie finds every labelled figure in the PDF and makes one card for each, all in one study set. The text of the PDF becomes flashcards and a quiz in the same set. In the app you take one photo for each diagram.
Yes, as long as the labels are legible. A clean image file gives the best result, but a photo works too, and so does your own labelled sketch.
Three study sets are free, on the web or in the app, and an image occlusion set counts as one of them. A PDF with many diagrams is one set, not one set for each diagram.
