Battery guide
Working Memory Capacity Battery guide
Three tests of holding and reordering information, for working memory research: letter-number sequencing, size ordering and reading span.
- Guide version
- 1.2.0
- Battery version
- 1.0.0
What it measures
Who it is for: Working memory research.
It measures Reordering letters and numbers, Ordering pictures by size and Complex span with reading.
Working memory: Holding and updating information for a few seconds.
Scores describe how a person performs on these tasks. Research use only.
Tests in order
The tests run in this order. A study started from the battery keeps the order and the settings.
1. Letter-Number Sequencing Task. Measures working memory with mixed runs of numbers and letters. Participants see each run one item at a time, then enter the numbers in ascending order followed by the letters in alphabetical order.
2. Size Order Memory Test. Measures working memory with pictures of animals and foods. Participants see each list one picture at a time, then tap the pictures from smallest to largest in real life.
3. Reading Span Task. Measures working memory capacity with the automated reading span procedure. Participants judge whether sentences make sense while remembering letters, then recall the letters in order.
| Order | Test | Domain | Time |
|---|---|---|---|
| 1 | Letter-Number Sequencing Task | Working memory | 5 to 8 minutes |
| 2 | Size Order Memory Test | Working memory | 6 to 10 minutes |
| 3 | Reading Span Task | Working memory | 12 to 16 minutes |
Time and devices
Allow about 34 minutes for the whole battery. The table gives each test's time.
Participants can use a desktop or laptop, tablet or phone.
On a desktop or laptop the screen must be at least 1024 by 700 pixels.
A tablet or phone needs a screen of at least 360 by 640 pixels.
On phones and tablets, each test is compared only with sessions on the same kind of device. A test shows a percentile there once that reference group holds 50 valid sessions in the participant's age band; until then the report shows raw scores and says so.
Participants need Chrome, Edge, Firefox or Safari.
| Test | Timing | Devices |
|---|---|---|
| Letter-Number Sequencing Task | Untimed | Desktop or laptop, tablet or phone |
| Size Order Memory Test | Untimed | Desktop or laptop, tablet or phone |
| Reading Span Task | Untimed | Desktop or laptop, tablet or phone |
Languages
Runs in English only: Reading Span Task keeps its words and sentences in English.
How to give it
Start a study from the battery in the app. The tests, their order and their settings are already set and stay fixed. If you change, reorder or customize a test, the study becomes a custom study and no longer carries the battery.
Each test opens with its instructions. Participants see these:
Letter-Number Sequencing Task: Numbers and letters appear one at a time. Remember them, then enter the numbers from smallest to largest, followed by the letters in alphabetical order.
Size Order Memory Test: Pictures of animals and foods appear one at a time. Remember them, then tap them from smallest to largest in real life. In the second part, tap the foods first, then the animals.
Reading Span Task: Read each sentence, choose whether it makes sense, and remember the letter that follows. After each set, click the letters in the order they appeared.
| Step | Before you invite participants |
|---|---|
| 1 | Recruit participants who read English well. |
| 2 | Ask participants to take the battery in one quiet sitting, without help, and not to write anything down. |
| 3 | Pilot the battery yourself: the three tasks take about 34 minutes. |
How each test is scored
The server scores each test when the participant finishes it. The primary score is the one the app compares with a norm. The other scores are reported with it.
Every result records its scoring version. For this battery they are Letter-Number Sequencing Task 1.0.0, Size Order Memory Test 1.0.0 and Reading Span Task 1.0.0.
| Test | Score | What it is | Better |
|---|---|---|---|
| Letter-Number Sequencing Task | Runs Correct (primary) | Runs entered correctly: the digits in ascending order, then the letters in alphabetical order (0 to 21 at the standard settings). | Higher is better |
| Letter-Number Sequencing Task | Longest Span | The longest run length, in items, entered correctly at least once (0 when none was). | Higher is better |
| Letter-Number Sequencing Task | Proportion Correct (proportion) | Runs entered correctly out of the runs given. | Higher is better |
| Letter-Number Sequencing Task | Runs Given | Test runs given before the test ended (21 at the standard settings without the stop rule). | Informational |
| Letter-Number Sequencing Task | Wrong-Item Errors | Entries that do not hold exactly the items shown: an item missing, added or changed. | Lower is better |
| Letter-Number Sequencing Task | Letters-First Errors | Entries with the right items but a letter before a digit. | Lower is better |
| Letter-Number Sequencing Task | Order Errors | Entries with the right items, digits first, but the digits not ascending or the letters not in alphabetical order. | Lower is better |
| Letter-Number Sequencing Task | Median Entry Time (ms) | Median time from the entry screen to Submit, over all runs. | Informational |
| Letter-Number Sequencing Task | Median Entry Time, Correct Runs (ms) | Median time from the entry screen to Submit, over runs entered correctly. | Informational |
| Size Order Memory Test | Lists Correct (primary) | Lists given back in exactly the right order, over both parts (0 to 24 at the standard settings). | Higher is better |
| Size Order Memory Test | Lists Correct, Part 1 | Lists of one category given back in exactly the right order (0 to 12 at the standard settings). | Higher is better |
| Size Order Memory Test | Lists Correct, Part 2 | Mixed lists given back in exactly the right order (0 to 12 at the standard settings). Null when part 2 is turned off. | Higher is better |
| Size Order Memory Test | Longest List, Part 1 | The longest list, in pictures, given back correctly at least once in part 1 (0 when none was). | Higher is better |
| Size Order Memory Test | Longest List, Part 2 | The longest list, in pictures, given back correctly at least once in part 2 (0 when none was). Null when part 2 is turned off. | Higher is better |
| Size Order Memory Test | Pictures in Position | Pictures in a right position, over all lists. | Higher is better |
| Size Order Memory Test | Other Pictures Picked | Pictures left in an answer that were not in the list, over all lists. | Lower is better |
| Size Order Memory Test | Median Time per List (ms) | Median time on the answer screen per list, leaving out times under 100 ms. | Informational |
| Size Order Memory Test | Anticipations | Lists answered in under 100 ms. | Lower is better |
| Size Order Memory Test | Lists Given | Test lists given before the task ended (24 at the standard settings when no part stops early). | Informational |
| Size Order Memory Test | Practices Finished | Parts whose practice lists were all answered. Feeds the quality rule. | Informational |
| Size Order Memory Test | Parts Planned | Parts in the session's settings: 2 at the standard settings. | Informational |
| Size Order Memory Test | Parts Started | Parts whose two lists of 2 pictures were answered. Feeds the quality rule. | Informational |
| Size Order Memory Test | 2-Picture Lists Correct | Lists of 2 pictures given back correctly, over both parts. Feeds the quality rule. | Higher is better |
| Reading Span Task | Partial Span Score (primary) | Letters recalled in the correct position across all sets (0 to 75 at the standard settings). | Higher is better |
| Reading Span Task | Absolute Span Score | Sum of set sizes for sets recalled perfectly. | Higher is better |
| Reading Span Task | Partial-Credit Unit Score (proportion) | Mean proportion of letters recalled in the correct position per set. | Higher is better |
| Reading Span Task | Sentence Accuracy (proportion) | Sentences judged correctly within the time limit, out of all sentences shown. | Below 0.85 flags the session |
| Reading Span Task | Sentence Errors | Speed errors plus accuracy errors. | Lower is better |
| Reading Span Task | Speed Errors | Sentences not read within the participant's time limit. | Lower is better |
| Reading Span Task | Accuracy Errors | Sentences judged wrongly as making sense or not. | Lower is better |
| Reading Span Task | Low Sentence Accuracy | 1 when sentence accuracy is below 85%; review before analysis. | Informational |
| Reading Span Task | Recall, Sets of 3 (proportion) | Proportion of letters recalled in the correct position in sets of 3. | Higher is better |
| Reading Span Task | Recall, Sets of 4 (proportion) | Proportion of letters recalled in the correct position in sets of 4. | Higher is better |
| Reading Span Task | Recall, Sets of 5 (proportion) | Proportion of letters recalled in the correct position in sets of 5. | Higher is better |
| Reading Span Task | Recall, Sets of 6 (proportion) | Proportion of letters recalled in the correct position in sets of 6. | Higher is better |
| Reading Span Task | Recall, Sets of 7 (proportion) | Proportion of letters recalled in the correct position in sets of 7. | Higher is better |
| Reading Span Task | Median Reading Time (ms) | Median time to read a sentence and click Continue, for sentences read within the time limit. | Context for the time limit |
| Reading Span Task | Reading Time Limit (ms) | The participant's time limit per sentence: mean practice reading time plus 2.5 SD. | Informational |
Session quality rules
The app checks every session when it scores it and records one of four states.
An Invalid session stays in the study's results, labelled with its reason, and does not count toward norms.
A session can carry warnings and still be valid. The results list the warnings next to the scores.
| State | What it means |
|---|---|
| Norm-ready | The session passed every check and a norm exists for it, so the app can show a percentile. |
| Raw-only | The scores are usable, but the app shows no percentile. Typical reasons are no norm for the test, changed settings, or a warning that makes a comparison unfair, such as a restart or a screen too short for the display. |
| Invalid technical | The setup broke the timing or the task. Examples are leaving full screen, a browser tab that lost focus during a timed test, and long pauses. |
| Invalid behavioral | The responses suggest the task was not done as asked. Examples are a failed attention check, repeated switching away from the task, and accuracy at or below chance on a choice task. |
Published norms used
No published norm is used for any test in this battery.
ConductCognition also builds norms from its own participants. An age band of a test uses them once it holds at least 50 valid sessions on the same device and input type, run with standard settings and scored with the current scoring version. Sessions from paying customers' studies and from clinical or patient samples do not count.
A report shows a percentile only when the app has stored one for that session. Otherwise it shows the raw scores.
Every reference group covers ages 18 and over. No reference group covers a participant under 18, so their report shows raw scores only, and their sessions do not count toward norms.
How to cite
ConductScience, Inc. Working Memory Capacity Battery guide, version 1.2.0. ConductCognition. https://conductcognition.com/batteries/working-memory-capacity/guide
Cite the guide version you used. Name the battery version (1.0.0) and the scoring versions listed in this guide.