Attention
Dichotic Listening Task
Also called: dichotic listening paradigm, consonant-vowel dichotic listening, CV syllable dichotic listening, forced-attention dichotic listening, right-ear advantage, ear advantage task
Measure the ear advantage for speech: a different syllable in each ear through headphones, the one heard best chosen, then attending to each ear in turn.
8-11 minUntimed
Free to start: 10 free participants per account, then $0.99 per participant for academic research, or any yearly plan. Try it here first, with no account.
- Papers, 2021 to 2025
- 280
- Evidence grade
- B
- Registered clinical studies
- 15
What it measures
Measures the ear advantage for speech sounds. Through headphones, a different syllable such as ba or ka plays in each ear at the same moment, and participants choose the one they heard, first with no instruction and then attending to the right or the left ear. The main score is the laterality index: how much more often the right ear's syllable was reported than the left's.
Constructs
- Hemispheric asymmetry for speech
- Auditory selective attention
- Cognitive control of attention
Research uses
- Language lateralization research
- Auditory attention and cognitive control research
- Development and aging research, at the group level
How the paradigm works
The Dichotic Listening Task measures the ear advantage for speech: when two different speech sounds reach the two ears at the same moment, most people report the right ear's sound more often, a sign of the left hemisphere's part in speech perception (Kimura, 1961; Studdert-Kennedy and Shankweiler, 1970). This version uses the six stop consonants with the vowel a, ba, da, ga, pa, ta and ka, paired in every combination for the left and the right ear (Hugdahl and colleagues, 2009). It needs headphones and normal hearing. The test starts with the sound setup: the syllables load, the participant turns the device's volume until a steady tone is comfortable, and a six-trial headphone check (Woods, Siegel, Traer and McDermott, 2017) confirms that headphones are in use. A left-right check then plays a short tone in one ear at a time and asks which side it came from, because the score depends on each ear getting its own syllable; after an error the participant checks the earphones and hears a second round. By default a failed check ends the test, and both checks' results are saved either way.
More about the paradigm
On each trial the participant presses Play, hears a pair, and chooses one of six syllable buttons, with no time limit. A block plays all 36 pairs once, 30 with a different syllable in each ear and 6 with one syllable in both, in an order drawn from the session's seed. The standard design follows the forced-attention paradigm (Hugdahl and Andersson, 1986): a block with no instruction (choose the sound heard best) comes first, then a block attending to the right ear and one attending to the left, in an order drawn from the seed. The non-forced design runs three blocks with no instruction instead. Six practice trials, each syllable once in both ears, show the sound that played; the test gives no feedback. The syllables are synthetic speech, made by formant synthesis in the platform's own code, not recordings of a person: one vowel, pitch and length in all six, prevoiced b, d and g and aspirated p, t and k, every file aligned at the start of the vowel so the two ears' vowels start on the same sample. Each plays at a fixed level, 12 dB below the volume-setting tone.
The main score is the laterality index over the trials with no instruction: 100 times the right-ear reports minus the left-ear reports, over their sum, so +100 means only right-ear reports and -100 only left-ear ones. Published samples show a right-ear advantage on average, larger in some languages and samples than others (Bless and colleagues, 2013). The attention blocks give the same index and the attended ear's share, which shows how far attending to one ear moves the reports (Hugdahl and colleagues, 2009). One block of about 40 trials gives a less reliable index than three: test-retest intraclass correlations were .64 and .65 for 40 trials and .91 and .93 for 120 trials in Westerhausen and Samuelsen (2020), and .78 for 36 trials on a smartphone in Bless and colleagues (2013); the non-forced design pools its three blocks. Handedness and a difference in hearing between the ears also move the ear advantage, so studies usually record handedness and compare groups. The test does not measure or screen hearing: scores are research measures and do not diagnose.
Scores
- Laterality Indexscore
- 100 x (right-ear reports - left-ear reports) / (right + left), over the trials with no instruction and a different syllable in each ear.
- Positive means a right-ear advantage; neither direction is better
- Right Ear Reports%
- Share of the trials with no instruction whose answer named the right ear's syllable.
- Informational
- Left Ear Reports%
- Share of the trials with no instruction whose answer named the left ear's syllable.
- Informational
- Errors%
- Share of the trials with no instruction whose answer named neither syllable.
- Lower means the syllables were heard more clearly
- Laterality Index, Attend Rightscore
- The laterality index in the block attending to the right ear.
- Usually higher than with no instruction
- Laterality Index, Attend Leftscore
- The laterality index in the block attending to the left ear.
- Usually lower than with no instruction
- Right Ear Reports, Attend Right%
- Share of the right ear's syllable in the block attending to the right ear.
- Informational
- Left Ear Reports, Attend Left%
- Share of the left ear's syllable in the block attending to the left ear.
- Informational
- Gain from Attending Rightscore
- Right-ear reports attending to the right ear minus with no instruction, in percentage points.
- Positive means attending moved the reports to the right ear
- Gain from Attending Leftscore
- Left-ear reports attending to the left ear minus with no instruction, in percentage points.
- Positive means attending moved the reports to the left ear
- Same-Syllable Accuracy%
- Share of the trials with one syllable in both ears answered with that syllable.
- Under 0.5 is flagged for review
- Median Answer Timems
- Median time from when the answers opened, after the pair, to the answer.
- Informational; the answer has no time limit
- Anticipationscount
- Answers within 100 ms of the answers opening, which leave the scores.
- Half or more of the answers makes the session invalid
- Completed Trialstrials
- Trials answered in the scored run.
- Fewer than planned is flagged for review
- Planned Trialstrials
- Trials the run set out to play.
- Informational
- Left-Right Check Passed0/1
- 1 when every tone of a round of the left-right check was placed on its side, 0 when the second round had an error too.
- 0 stops the test unless the study set it to continue
- Left-Right Check Roundscount
- Rounds of the left-right check played: 1, or 2 after an error.
- Informational
- Headphone Check Passed0/1
- 1 when the headphone check passed (at least 5 of 6 right), 0 when it did not.
- 0 stops the test unless the study set it to continue
- Headphone Check Correctcount
- Headphone check trials answered right, of 6.
- 5 or 6 passes
- Reported Output Delayms
- Output delay the device reported to the browser; empty when the browser does not report it.
- Informational
Use and evidence
280 papers from 2021 to 2025 name this task in their title or abstract, down 18% compared with 2016 to 2020. That ranks it 97 of 495 test families in our census. See the counts for every test.
Show the numbers
| Year | Papers |
|---|---|
| 2025 | 64 |
| 2024 | 58 |
| 2023 | 48 |
| 2022 | 55 |
| 2021 | 55 |
| 2020 | 77 |
| 2019 | 69 |
| 2018 | 72 |
| 2017 | 69 |
| 2016 | 56 |
| 2015 | 72 |
| 2014 | 78 |
| 2013 | 72 |
| 2012 | 73 |
| 2011 | 93 |
| 2010 | 55 |
| 2009 | 72 |
| 2008 | 73 |
| 2007 | 41 |
| 2006 | 54 |
| 2005 | 52 |
| 2004 | 51 |
| 2003 | 68 |
| 2002 | 52 |
| 2001 | 47 |
| 2000 | 59 |
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
- 48
- Papers on reliability or validity
- 189
- Registered clinical studies using it as an outcome
- 15
Published reliability
- A smartphone version retested at ICC .78 and showed the expected right-ear advantage. (Bless et al. 2013) https://doi.org/10.3389/fpsyg.2013.00042
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 0.22.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
Task design
The trial sequence as the test runs in ConductCognition.
- Sound setup
- The syllables load, the participant turns the device's volume until a steady 1 kHz tone is comfortable, then takes a 6-trial headphone check (Woods and colleagues, 2017). A left-right check follows: a 1,000 Hz tone in one ear, 4 times, and after an error a second round of 4. By default a failed check ends the test; both results are saved either way.
- Syllables
- Six synthetic syllables, ba, da, ga, pa, ta and ka, made by formant synthesis in our own code, not recorded from a person. One vowel, pitch and length in all six; only the consonant differs, with prevoiced b, d and g and aspirated p, t and k. Every file's vowel starts 150 ms in, so a pair's vowels start on the same sample in both ears.
- Trial
- Press Play to hear one syllable in each ear at the same moment, then choose one of six buttons, three to a row, with no time limit.
- Blocks
- Three blocks of the 36 pairs, each pair once per block in an order drawn from the session's seed: 30 pairs with a different syllable in each ear and 6 with one in both, 108 trials. Forced attention (standard): no instruction first, then attending to the right ear and to the left in a seeded order. Non-forced: three blocks with no instruction.
- Practice
- 6 trials, each syllable once in both ears, showing the sound that played for 1,000 ms.
- Level
- Every syllable 12 dB below the volume-setting tone, a level relative to the volume the participant set.
- Score
- The laterality index over the pairs with a different syllable in each ear, in the blocks with no instruction: 100 x (right-ear reports - left-ear reports) / (right + left), with each ear's share. The attention blocks give the same index and the attended ear's share. Answers under 100 ms leave the scores.
The syllables are synthetic speech, not the recorded syllables of published versions, and the level is relative to the volume the participant set, so compare results within studies run the same way. Handedness and a difference in hearing between the ears move the ear advantage, so studies usually record handedness and compare groups. The test needs normal hearing and headphones, and it does not measure or screen hearing. The scores support research and do not diagnose.
Quality checks
Each session is marked valid, needs review or invalid, with the reason, before you see its scores.
Scored rows: dichotic_listening_test from the scored run, one of six syllable buttons after the pair has played, with no time limit, graded from the saved button and the two syllables played. An answer is right when it names a syllable that played (chance 1 in 3 with two different syllables, 1 in 6 with one in both ears). Below chance invalidates and not above chance is flagged; one button on 90% of answers invalidates when accuracy is not above chance; answers under 100 ms invalidate when they are at least half. A headphone check or left-right check that stopped the test invalidates; a failed check with the test run anyway, fewer than half the one-syllable trials answered with that syllable, or a run short of its planned trials is flagged for review.
Why these rules
Accuracy significantly below chance (one-sided exact test, p < .05) cannot come from guessing; it means the response mapping was reversed or the task was not followed (Slick, Sherman and Iverson 1999 treat below-chance forced-choice performance as definite response bias). Chance-level accuracy can be a real result in impaired participants, so it is only flagged. One option on at least 90% of answered trials, when the correct options are balanced and accuracy is not above chance, means the answers did not depend on the items (the task counterpart of long-string responding in surveys; Curran 2016). The answers open once the pair has played and have no time limit, so an answer under 100 ms was pressed before they opened, and only a session made mostly of such answers is invalid. Woods, Siegel, Traer and McDermott (2017) let only listeners who passed the headphone check go on, because a listener on loudspeakers hears the sounds differently; a session that ran after a failed check keeps its scores but not its percentile. The ear advantage needs each ear's syllable in that ear, so a left-right check stands beside the headphone check. Bless and colleagues (2013) left out sessions with more than three errors on the six one-syllable pairs.
No percentile. Scores and quality flags only.
Running this test
Settings you can change
| Setting | Standard | Allowed |
|---|---|---|
| Blocks | Forced attention: no instruction, then right and left | Forced attention: no instruction, then right and left, Non-forced: three blocks with no instruction |
| When the headphone check fails | Stop the test | Stop the test, Continue the test |
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, tablets and phones. Needs headphones. 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 Dichotic Listening Task in a web browser (ConductCognition task version 1.0.0, scoring version 1.0.0; Kimura, 1961; Hugdahl and Andersson, 1986), with the standard settings (blocks: Forced attention: no instruction, then right and left; when the headphone check fails: Stop the test). The main score was laterality index (100 x (right-ear reports - left-ear reports) / (right + left), over the trials with no instruction and a different syllable in each ear).
ConductCognition versions: task version 1.0.0, scoring version 1.0.0. Every export records the versions each session used, for a methods section.
- Kimura, D. (1961). Cerebral dominance and the perception of verbal stimuli. Canadian Journal of Psychology, 15(3), 166-171. https://doi.org/10.1037/h0083219Dichotic listening and the right-ear advantage for speech.
- Studdert-Kennedy, M., & Shankweiler, D. (1970). Hemispheric specialization for speech perception. The Journal of the Acoustical Society of America, 48(2B), 579-594. https://doi.org/10.1121/1.1912174Right-ear advantages for stop consonants in dichotic syllable pairs.
- Hugdahl, K., & Andersson, L. (1986). The "forced-attention paradigm" in dichotic listening to CV-syllables: A comparison between adults and children. Cortex, 22(3), 417-432. https://doi.org/10.1016/S0010-9452(86)80005-3The six stop consonants with a, and the blocks with no instruction and attending to each ear.
- Hugdahl, K., Westerhausen, R., Alho, K., Medvedev, S., Laine, M., & Hämäläinen, H. (2009). Attention and cognitive control: Unfolding the dichotic listening story. Scandinavian Journal of Psychology, 50(1), 11-22. https://doi.org/10.1111/j.1467-9450.2008.00676.xThe forced-attention paradigm as a measure of attention and cognitive control.
- Bless, J. J., Westerhausen, R., Arciuli, J., Kompus, K., Gudmundsen, M., & Hugdahl, K. (2013). "Right on all occasions?" On the feasibility of laterality research using a smartphone dichotic listening application. Frontiers in Psychology, 4, 42. https://doi.org/10.3389/fpsyg.2013.00042The 36 pairs on a smartphone with six answer buttons, the laterality index, and its test-retest reliability.
- Westerhausen, R., & Samuelsen, F. (2020). An optimal dichotic-listening paradigm for the assessment of hemispheric dominance for speech processing. PLOS ONE, 15(6), e0234665. https://doi.org/10.1371/journal.pone.0234665Reliability rising with the number of trials, from 40 to 120.
- Karlsson, E. M., Hugdahl, K., Hirnstein, M., & Carey, D. P. (2023). Analysis of distributions reveals real differences on dichotic listening scores between left- and right-handers. Cerebral Cortex Communications, 4(2), tgad009. https://doi.org/10.1093/texcom/tgad009The 36 pairs, six with one syllable in both ears, in three blocks, and handedness and the ear advantage.
- Klatt, D. H. (1980). Software for a cascade/parallel formant synthesizer. The Journal of the Acoustical Society of America, 67(3), 971-995. https://doi.org/10.1121/1.383940The formant synthesis behind the syllables.
- Woods, K. J. P., Siegel, M. H., Traer, J., & McDermott, J. H. (2017). Headphone screening to facilitate web-based auditory experiments. Attention, Perception, & Psychophysics, 79(7), 2064-2072. https://doi.org/10.3758/s13414-017-1361-2The headphone check before the test.
Source papers
- Bless JJ, Westerhausen R, Arciuli J, Kompus K, Gudmundsen M, Hugdahl K (2013). "Right on all occasions?" On the feasibility of laterality research using a smartphone dichotic listening application. Frontiers in Psychology, 4:42.N 76, Adults
- Westerhausen R, Samuelsen F (2020). An optimal dichotic-listening paradigm for the assessment of hemispheric dominance for speech processing. PLOS ONE, 15(6):e0234665.N 50, 19-39
Questions
How long does the Dichotic Listening Task take?
About 8 to 11 minutes, as listed in the test library.
What device does a participant need?
Untimed test: runs on desktops, laptops, tablets and phones. Needs headphones. The browser must be Chrome, Edge, Firefox or Safari.
What scores does it produce?
Laterality Index, Right Ear Reports, Left Ear Reports, Errors, Laterality Index, Attend Right, Laterality Index, Attend Left, Right Ear Reports, Attend Right, Left Ear Reports, Attend Left, Gain from Attending Right, Gain from Attending Left, Same-Syllable Accuracy, Median Answer Time, Anticipations, Completed Trials, Planned Trials, Left-Right Check Passed, Left-Right Check Rounds, Headphone Check Passed, Headphone Check Correct and Reported Output Delay. Each session is also marked valid, needs review or invalid, with the reason.
How widely is the Dichotic Listening Task used in research?
280 papers from 2021 to 2025 name it in their title or abstract, down 18% compared with 2016 to 2020. That ranks it 97 of 495 test families in the ConductCognition test census (use grade C). Source: ConductCognition test census 0.22.0, counted 31 October 2026 from OpenAlex and ClinicalTrials.gov.
How much reliability evidence does the Dichotic Listening Task have?
In the published research, 48 papers report its test-retest reliability and 15 registered clinical studies use it as an outcome (evidence grade B in the ConductCognition test census). A smartphone version retested at ICC .78 and showed the expected right-ear advantage. (Bless et al. 2013)
Does it report a percentile?
No. Scores and quality flags only.
Which settings can a researcher change?
Blocks (Forced attention: no instruction, then right and left, Non-forced: three blocks with no instruction) and when the headphone check fails (Stop the test, Continue the test). 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.
Every test: the full test list.
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