Processing Speed
Spiral Drawing Test
Also called: Archimedean spiral, spiral analysis, digitized spiral drawing, spiral tracing
Measure drawing accuracy and steadiness as participants trace a spiral with each hand, with every pointer sample timed and the drawing unraveled for analysis.
3-5 minUntimed
Free to start: 10 free participants per account, then $0.99 per participant for academic research, or any yearly plan. Preview any test free after you sign up.
- Papers, 2021 to 2025
- 170
- Evidence grade
- B
- Registered clinical studies
- 11
What it measures
A research measure of drawing accuracy and steadiness. Participants trace a five-loop spiral from the center outward, first with the hand they write with and then with the other hand. Every pointer sample is recorded with its time, and the main score is how far the writing hand's line strays from the spiral.
Constructs
- Fine motor control
- Visuomotor tracking
- Movement steadiness
Research uses
- Tremor and movement research
- Motor aging research
- Within-study group comparison
How the paradigm works
The spiral drawing test is a research measure of drawing accuracy and steadiness. A spiral of five loops is drawn in gray on a white square, with a green dot at its center and a red dot at its end. Participants trace its line from the center outward with a mouse, a finger or a stylus, at their usual pace, and press Done at the end. A two-loop practice spiral with the writing hand comes first, followed by feedback on where the drawing started, its direction, how far it went and how close it stayed to the line. The standard run then has 2 spirals with the hand the participant writes with and 2 with the other hand. A study can set 1 to 4 spirals per hand and set the writing hand instead of asking.
More about the paradigm
The template is an Archimedean spiral following Haubenberger and colleagues (2011): five loops turning clockwise from the inside out, with the space between loops one fifth of the largest radius. It is scaled to fill the drawing area, so every length is measured in loop spacings and needs no screen calibration. Participants trace the line itself, where Haubenberger and colleagues had patients draw between printed loops. Every pointer sample is saved with its time, from the browser's coalesced pointer events where available, with the pointer type, the sampling rate and every lift. A spiral keeps up to 250 samples per second, and very long drawings are thinned so that each spiral fits in one saved row.
Each drawing is unraveled into radius against angle around the center, as in the digitized spiral analyses of Elble, Sinha and Higgins (1990) and Pullman (1998). The main score is the writing hand's mean radial deviation: the distance of the line from the nearest loop, along the radius, as a share of the loop spacing. For each hand the scores also give the share of the spiral traced, drawing time and speed, speed variability, a smoothness index from the unraveled drawing, and the frequency and amplitude of the largest oscillation between 4 and 12 Hz in the drawing's velocity spectrum. The amplitude is measured within 1 Hz of that peak, as Haubenberger and colleagues did, and both tremor scores need at least 50 samples per second. The scores support research on movement and do not diagnose tremor or any other condition.
Scores
- Writing Hand Deviation%
- Mean distance of the line from the nearest loop of the spiral, along the radius and weighted by the length drawn, as a share of the space between loops.
- Lower means the line stayed closer to the spiral; 0.5 is halfway between two loops
- Other Hand Deviation%
- Mean radial deviation of the other hand's spirals, as a share of the space between loops.
- Lower means the line stayed closer to the spiral
- Writing Hand Coverage%
- Turns drawn clockwise around the center as a share of the spiral's turns outside its first quarter turn.
- 1 for a whole spiral; below 0.75 is flagged for review, and below 0 means drawn the other way round
- Other Hand Coverage%
- Share of the spiral traced by the other hand, as for the writing hand.
- 1 for a whole spiral; below 0.75 is flagged for review
- Writing Hand Drawing Timeseconds
- Mean time from the first to the last point of a spiral.
- Lower is faster; speed is not the aim of the task
- Other Hand Drawing Timeseconds
- Mean time from the first to the last point of the other hand's spirals.
- Lower is faster; speed is not the aim of the task
- Writing Hand Speedspacings/s
- Length drawn per second while the pointer was down, in spaces between loops.
- Higher is faster
- Other Hand Speedspacings/s
- Drawing speed of the other hand, in spaces between loops per second.
- Higher is faster
- Writing Hand Speed Variabilityscore
- Coefficient of variation of the drawing speed over 100 ms steps.
- Lower means a steadier speed
- Other Hand Speed Variabilityscore
- Coefficient of variation of the other hand's drawing speed over 100 ms steps.
- Lower means a steadier speed
- Writing Hand Smoothness Indexscore
- Coefficient of variation of the growth in radius over each 30 degrees of the unraveled drawing.
- 0 for an even spiral; higher means a more uneven line
- Other Hand Smoothness Indexscore
- Smoothness index of the other hand's spirals.
- 0 for an even spiral; higher means a more uneven line
- Writing Hand Tremor FrequencyHz
- Frequency of the largest peak in the drawing's velocity spectrum between 4 and 12 Hz. Empty below 50 samples per second or without 2.56 seconds of unbroken drawing.
- Informational; read it with the amplitude
- Other Hand Tremor FrequencyHz
- Largest 4 to 12 Hz peak of the other hand's velocity spectrum.
- Informational; read it with the amplitude
- Writing Hand Tremor Amplitude%
- Root mean square movement within 1 Hz of the tremor frequency, as a share of the space between loops.
- Lower means less oscillation between 4 and 12 Hz
- Other Hand Tremor Amplitude%
- Root mean square movement of the other hand within 1 Hz of its tremor frequency, in spaces between loops.
- Lower means less oscillation between 4 and 12 Hz
- Writing Hand Liftscount
- Mean times the pointer was lifted during a spiral.
- 0 when each spiral was drawn in one stroke
- Other Hand Liftscount
- Mean lifts per spiral with the other hand.
- 0 when each spiral was drawn in one stroke
- Spirals Scoredcount
- Test spirals with a drawn line.
- Twice the spirals per hand when every spiral was drawn
- Sampling RateHz
- Median pointer samples per second kept over the scored spirals.
- Below 50 the tremor scores are empty and the session is flagged for review
- Writes with Left Hand0/1
- 1 when the participant writes with the left hand, which then counts as the writing hand.
- Shows which hand the scores call the writing hand
- Pointer Types%
- Share of the pointer samples from a mouse, a pen or touch, keyed by type.
- More than one type is flagged for review
Use and evidence
170 papers from 2021 to 2025 name this task in their title or abstract, up 158% compared with 2016 to 2020. That ranks it 139 of 395 test families in our census. See the counts for every test.
Show the numbers
| Year | Papers |
|---|---|
| 2025 | 54 |
| 2024 | 39 |
| 2023 | 35 |
| 2022 | 24 |
| 2021 | 18 |
| 2020 | 15 |
| 2019 | 16 |
| 2018 | 11 |
| 2017 | 10 |
| 2016 | 14 |
| 2015 | 12 |
| 2014 | 11 |
| 2013 | 17 |
| 2012 | 9 |
| 2011 | 9 |
| 2010 | 8 |
| 2009 | 8 |
| 2008 | 4 |
| 2007 | 2 |
| 2006 | 10 |
| 2005 | 5 |
| 2004 | 2 |
| 2003 | 0 |
| 2002 | 0 |
| 2001 | 2 |
| 2000 | 3 |
Use grade C
100 to 299 papers from 2021 to 2025.
Evidence grade B
At least 8 test-retest papers, and either 5 registered clinical studies or 150 reliability or validity papers.
- Papers on test-retest reliability
- 14
- Papers on reliability or validity
- 69
- Registered clinical studies using it as an outcome
- 11
How the grades work
Use: A is 1,000 or more papers from 2021 to 2025, B 300 to 999, C 100 to 299, D 30 to 99 and E fewer than 30. Evidence: A means at least 25 papers report its test-retest reliability and at least 25 registered clinical studies use it as an outcome; B, at least 8 test-retest papers, and either 5 registered clinical studies or 150 reliability or validity papers; C, at least 2 test-retest papers, 30 reliability or validity papers or 3 registered clinical studies; D, little published measurement evidence found. The counts measure use. They include every paper that names the task in its title or abstract. Grades describe the published research on this task, not ConductCognition's version of it.
Source: ConductCognition test census 0.14.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
Task design
The trial sequence as the test runs in ConductCognition.
- Template
- An Archimedean spiral of 5 loops turning clockwise from the center, with the space between loops one fifth of the largest radius, scaled to the drawing area.
- Drawing
- Traced on the line from the green center dot to the red end dot with a mouse, a finger or a stylus, then Done. No time pressure; a spiral ends by itself after 120 seconds.
- Spirals
- 2 per hand (standard, 1 to 4), the writing hand first.
- Writing hand
- Asked before the practice, or set by the study.
- Data
- Every pointer sample with its time, from coalesced pointer events where available, up to 250 per second, with the pointer type, the sampling rate and every lift.
- Practice
- A 2-loop spiral with the writing hand, then feedback on the start, direction, coverage and closeness to the line.
- Scores
- Radial deviation from the nearest loop as a share of the loop spacing, coverage, speed, smoothness, and the largest 4 to 12 Hz oscillation with its amplitude within 1 Hz of the peak.
Mouse, finger and stylus drawings differ, so each result records the pointer used and no percentiles are given. The scores support research on movement and do not diagnose tremor.
Quality checks
Each session is marked valid, needs review or invalid, with the reason, before you see its scores.
Scored rows: spiral_drawing_test from the scored run, one per spiral. A drawing has no correct option, so accuracy is not judged against chance. A session with no drawing on any spiral is invalid. A hand whose spirals cover less than 75% of the template's turns on average, a spiral drawn the other way round, a trace stored at fewer than 50 samples per second, and drawing with more than one kind of pointer are flagged for review.
Why these rules
Every score comes from the drawn path, so a session with no path has nothing to score. An incomplete or reversed spiral was not traced as instructed, so its accuracy and speed do not compare with complete spirals. Below 50 samples per second the 4 to 12 Hz band cannot be measured, so the tremor scores stay empty. Mouse, finger and pen drawings differ, so a session that mixes them is flagged.
No percentile. Scores and quality flags only.
Running this test
Settings you can change
| Setting | Standard | Allowed |
|---|---|---|
| Spirals per hand | 2 | 1 to 4 |
| Writing hand | Ask the participant (standard) | Ask the participant (standard), Right, Left |
Yearly plans can change settings within these limits. Free and pay-as-you-go studies use the standard settings.
Need a setting this test does not have?
Devices and languages
- Untimed test: runs on desktops, laptops and tablets. Participant devices
- Languages: English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese.
- Available on: Every plan, including the free plan.
- No percentile. Scores and quality flags only. How norms work
- Recruiting online? See the setup guides for Prolific, Sona Systems, CloudResearch Connect and Qualtrics.
Cite and describe
Participants completed the Spiral Drawing Test in a web browser (ConductCognition task version 1.0.0, scoring version 1.0.0; Elble, Sinha & Higgins, 1990; Pullman, 1998; Haubenberger et al., 2011), with the standard settings (spirals per hand: 2; writing hand: Ask the participant). The main score was writing hand deviation (mean distance of the line from the nearest loop of the spiral, along the radius and weighted by the length drawn, as a share of the space between loops).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
- Elble, R. J., Sinha, R., & Higgins, C. (1990). Quantification of tremor with a digitizing tablet. Journal of Neuroscience Methods, 32(3), 193-198. https://doi.org/10.1016/0165-0270(90)90140-BTremor measured from drawings on a digitizing tablet.
- Pullman, S. L. (1998). Spiral analysis: A new technique for measuring tremor with a digitizing tablet. Movement Disorders, 13(S3), 85-89. https://doi.org/10.1002/mds.870131315The handwritten Archimedean spiral recorded on a tablet and unraveled for analysis.
- Haubenberger, D., Kalowitz, D., Nahab, F. B., Toro, C., Ippolito, D., Luckenbaugh, D. A., Wittevrongel, L., & Hallett, M. (2011). Validation of digital spiral analysis as outcome parameter for clinical trials in essential tremor. Movement Disorders, 26(11), 2073-2080. https://doi.org/10.1002/mds.23808Five clockwise loops drawn from the inside out, and tremor amplitude within 1 Hz of the peak.
Source papers
- Elble RJ, Sinha R, Higgins C (1990). Quantification of tremor with a digitizing tablet. Journal of Neuroscience Methods, 32(3):193-198.Paradigm source
- Pullman SL (1998). Spiral analysis: a new technique for measuring tremor with a digitizing tablet. Movement Disorders, 13(Suppl 3):85-89.Paradigm source
- Haubenberger D, Kalowitz D, Nahab FB, Toro C, Ippolito D, Luckenbaugh DA, Wittevrongel L, Hallett M (2011). Validation of digital spiral analysis as outcome parameter for clinical trials in essential tremor. Movement Disorders, 26(11):2073-2080.Paradigm source, Adults
Questions
How long does the Spiral Drawing Test take?
About 3 to 5 minutes, as listed in the test library.
What device does a participant need?
Untimed test: runs on desktops, laptops and tablets. The browser must be Chrome, Edge, Firefox or Safari.
What scores does it produce?
Writing Hand Deviation, Other Hand Deviation, Writing Hand Coverage, Other Hand Coverage, Writing Hand Drawing Time, Other Hand Drawing Time, Writing Hand Speed, Other Hand Speed, Writing Hand Speed Variability, Other Hand Speed Variability, Writing Hand Smoothness Index, Other Hand Smoothness Index, Writing Hand Tremor Frequency, Other Hand Tremor Frequency, Writing Hand Tremor Amplitude, Other Hand Tremor Amplitude, Writing Hand Lifts, Other Hand Lifts, Spirals Scored, Sampling Rate, Writes with Left Hand and Pointer Types. Each session is also marked valid, needs review or invalid, with the reason.
How widely is the Spiral Drawing Test used in research?
170 papers from 2021 to 2025 name it in their title or abstract, up 158% compared with 2016 to 2020. That ranks it 139 of 395 test families in the ConductCognition test census (use grade C). Source: ConductCognition test census 0.14.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
How much reliability evidence does the Spiral Drawing Test have?
In the published research, 14 papers report its test-retest reliability and 11 registered clinical studies use it as an outcome (evidence grade B in the ConductCognition test census).
Does it report a percentile?
No. Scores and quality flags only.
Which settings can a researcher change?
Spirals per hand (1 to 4) and writing hand (Ask the participant (standard), Right, Left). Settings can be changed on yearly plans; free and pay-as-you-go studies use the standard settings.
Which languages can participants use?
Participants can take this test in English, Spanish, French, German, Italian, Portuguese (Brazil), Chinese (Simplified) and Japanese. English is on every plan, and the other languages come with yearly plans. Have a native speaker read the machine-translated text before launch.
Is this a clinical test?
No. ConductCognition is for research use only. It runs, scores and exports the test; clinical interpretation is outside the platform.
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