Use pictograms only when they reinforce the chart's message
For recall-oriented explanation of a single visualization, use pictorial shapes on the chart only when they reinforce the data or message to improve insight and address weak recognition for readers who need a visual hook.
- purpose:refine
- basis:empirical
- task:retrieve
- quality:insight
- lever:encoding
- channel:shape:use
- communication:resonance
advice
Add relevant pictograms, not decorative ones
Use pictograms only when they clearly reinforce the chart’s topic or message. For example, add a pictogram that matches the same concept named by the title or annotation, and remove pictograms that do not connect to the data or conclusion.
reason
Why relevant pictograms help
A relevant pictogram can act as a visual hook that helps the chart stand out and be retrieved from memory later. An unrelated pictogram can pull attention away from the data and lead readers toward the wrong interpretation.
Mechanism: When the pictogram matches the data or message, it creates a memorable visual association without reducing description quality; when it does not match, it can misdirect attention and confuse recall.
Evidence: Visualizations with pictograms had equal or better description quality than those without, and the paper reports that pictograms can improve recognition when used appropriately. It also notes that pictograms unrelated to the data or message can produce confusion and misdirect attention (Borkin et al., 2016).
context
Use when the chart needs a visual hook tied to the topic
- User Goal: Improve recognition and later recall of the visualization.
- Task: Explanation with later memory of the message.
- Chart Setting: The visualization includes or could include a human-recognizable object.
- Success Criterion: Viewers remember the chart and still recall the correct topic or message.
exceptions
Do not use this when the pictogram has no clear link to the data or message
Break it when: The pictogram is decorative and does not correspond to the chart’s topic, data, or conclusion. Why: The paper reports that such pictograms can confuse viewers and misdirect attention.
costs
Tradeoffs of pictograms
Sacrifice: You spend visual space and viewer attention on a non-textual cue.
Risk: An unrelated pictogram can become the most memorable part of the chart for the wrong reason.
Mitigation: Keep the pictogram tightly aligned with the same concept already expressed by the title, labels, or annotations.
mistakes
Common pictogram failure
Mistake: Adding a pictogram that is visually striking but semantically unrelated to the chart. Why it fails: Viewers may remember the object while misremembering the chart’s actual message.
check
Check whether the pictogram supports the message
Failure Sign: Reviewers mention the pictogram but misstate or miss the chart’s topic.
Quick Check: Ask whether the pictogram points to the same concept as the title or main annotation; if not, it is decorative noise.
Stronger Test: After a short viewing, ask a reviewer what the chart was about; if the pictogram is remembered but the message is not, revise or remove it.
fix
Fix pictogram use
- Replace decorative pictograms with ones that directly match the chart’s topic or conclusion.
- Remove pictograms whose connection to the data or message is unclear.
- Align the pictogram with the same concept already stated in the title or annotation.