-->PONE-D-25-14950-->-->Establishing standardized conditions for clinically available sound-localization tests: A multicenter approach-->-->PLOS ONE

Dear Dr. Yoshida,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Your manuscript has been reviewed by two experts in the topic. As you will see below, both reviewers found your study relevant and well-motivated, but they also had a number of concerns, including missing methodological details that would be required to replicate this study, and an insufficient contextualization of this work in the literature on spatial hearing. Both reviewers make very clear and detailed recommendations which I invite you to address in a revision of the paper. At this stage, I cannot guarantee publication, and the quality of your revisions would need to be assessed again, if possible by the same reviewers.

Please submit your revised manuscript by Jun 20 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:-->

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If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Patrick Bruns

Academic Editor

PLOS ONE

Journal requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

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2. Thank you for stating the following in the Competing Interests section:

[I have read the journal's policy and the authors of this manuscript have the following competing interests: This was a joint research project with RION Co., Ltd., which assisted purely in measuring the reflected sound. RION Co., Ltd. was not involved in any other aspect of this research, including the planning and implementation, data collection, analysis and interpretation, decision to publish, preparation, review, or approval of the paper.].

Please confirm that this does not alter your adherence to all PLOS ONE policies on sharing data and materials, by including the following statement: "This does not alter our adherence to  PLOS ONE policies on sharing data and materials.” (as detailed online in our guide for authors http://journals.plos.org/plosone/s/competing-interests).  If there are restrictions on sharing of data and/or materials, please state these. Please note that we cannot proceed with consideration of your article until this information has been declared.

Please include your updated Competing Interests statement in your cover letter; we will change the online submission form on your behalf.

3. In the online submission form, you indicated that [The data underlying the results presented in the study are available from Tadao Yoshida.].

All PLOS journals now require all data underlying the findings described in their manuscript to be freely available to other researchers, either 1. In a public repository, 2. Within the manuscript itself, or 3. Uploaded as supplementary information.

This policy applies to all data except where public deposition would breach compliance with the protocol approved by your research ethics board. If your data cannot be made publicly available for ethical or legal reasons (e.g., public availability would compromise patient privacy), please explain your reasons on resubmission and your exemption request will be escalated for approval.

4. Your ethics statement should only appear in the Methods section of your manuscript. If your ethics statement is written in any section besides the Methods, please move it to the Methods section and delete it from any other section. Please ensure that your ethics statement is included in your manuscript, as the ethics statement entered into the online submission form will not be published alongside your manuscript.

Additional Editor Comments (if provided):

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Reviewers' comments:

Reviewer's Responses to Questions

-->Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. -->

Reviewer #1: Yes

Reviewer #2: Partly

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-->2. Has the statistical analysis been performed appropriately and rigorously? -->

Reviewer #1: Yes

Reviewer #2: Yes

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-->3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.-->

Reviewer #1: No

Reviewer #2: No

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-->4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.-->

Reviewer #1: No

Reviewer #2: No

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-->5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)-->

Reviewer #1: The study explored localization abilities of sounds in the azimuthal dimension in order to establish standardized acoustic conditions for sound localization assessments in unilateral hearing loss and control individuals.

The multicenter approach is a plus-value. The method is clear. Establishing standardized tests is a key objective. I think the Results section could be improved, as well as the discussion. I think there is a lack of references in the introduction (eg. my comment 5).

I noticed some mistakes (eg. sentences written twice). The details are reported below in my comments.

It seems that the data availability statement does not fit with the requirements of Plos ONE. They state “No – some restrictions will apply” without explaining the exceptional situation as asked in the guidelines. I do not think this is a reason to reject the paper but I think it is necessary to explain why data is available only upon request to the author Tadao Yoshida.

General comments:

1) It is unclear whether the study was financially supported. In the Financial Disclosure you mention that “the author(s) received no specific funding for this work” but in the Acknowledgment section you mention “This research was supported by AMED under Grant Number JP24dk0310128.”. Could you clarify this please?

2) In the figure, I think it would be clearer if you also mention the azimuth position of the loudspeakers 1CH/2CH […]/ 9CH.

3) Please clarify the data availability statement to fit with the requirements of the journal.

Specific comments :

1) Lines 101-105 : You mention ILD and ITD as acoustic cues for spatial hearing. Please mention Interaural Phase Difference (IPD) which is an important cue when ITD and ILD are not sufficiently reliable.

2) Line 110 : If I have well understood what you mean by “frequency intensity”, you refer to the energy in a frequency band. I think it would be clearer if you use the term “energy” or “spectral component” instead of “frequency intensity”.

3) Lines 114- 115: you write “Thus, since these three elements (ITD, ILD, spectral cues), and changes in sound pressure due to the head-shadow effects are important in directional perception […]”. Can you explain why you mention separately ILD and the changes in sound pressure du to the head-shadow effects?

4) Lines 118-120 : You state “In general, sound-localization test results are worse in patients with unilateral hearing loss (UHL) than in healthy participants, and cognition on the side of the hearing-impaired ear is worse than that on the side of the normal-hearing ear. “ . I think there is a lack of references. Please mention references for sound-localization performance lower in patients with UHL than non-impaired. Also I think you could specify what you are referring to when you say “cognition” (for instance, give examples of tasks and references).

5) Lines 131 and 136: The ages of UHL patients and control individuals are different. Did you test the effect of age on performance? Auditory perception capabilities (comprising auditory localization) tend to decrease with age. I think you could mention it in the discussion.

6) Lines 275-276: It seems something is wrong with the sentence “A positive correlation of the envelope area with the differences between the number of correct responses between the left and right sides”. Is there a verb missing ? Please check this

7) Lines 318-379: the following sentence is already written line 299 : “In cases of UHL, the side of the worse-hearing ear was considered to be ch 9, and if the left ear was the worse-hearing ear side, the results were analyzed symmetrically.” Please check this

8) In the Result section, I think it is not enough clear whether the first results concern control individuals and UHL patients or just control individuals. Could you clarify this please? Also, I think it is not enough clear whether you tested the same predictors for the control group and the UHL patients. You mention effects for the control group but it is not clear if you this effects are also present in the UHL group. Is there interactions with the group (patients versus controls)?

9) Line 332: Do you have explanations for the non-effect of the noise type on performance ? I think it could be clearer if you mention again the low-pass filter (1500 Hz).

10) Line 339. In the discussion you mention “channels 1, 2, 8 and 9”. I think the discussion would be improved if you mention also the azimuth position in degree. Therefore the reader can easily linked the positions of your loudspeakers with the positions mentioned in the discussion (line 366 for instance).

11) Line 359-360: In the sentence “Some facilities demonstrated more than 10 discrepancies in the number of correct responses for loudspeakers in symmetrical positions”, please mention the total number of responses (eg 10 on how many?).

12) Lines 411-413: I think the readers could be interested in practical examples mentioned here on how to reduce the initial reflections (eg, absorbing materials..).

Reviewer #2: This paper describes a multi-center study to evaluate the effect of room reverberation on sound source localization for adults with vs. without unilateral hearing loss. Broadband and lowpass filtered noise was used. Results replicate two well-known findings: better localization accuracy at midline as compared to off midline, and deficits of localization for patients with unilateral hearing loss. Overall, similar results were obtained with the full-band and low-pass filtered noise. Of greatest interest here, performance differed between test sites. Acoustic analysis of sound recorded at each site indicate that performance is detrimentally affected by early reflections. Modifications of the test environments to reduce those reflections could presumably increase consistency of data cross sites.

The ultimate goal of this work, to configure and implement protocols for clinical assessment of localization, is valuable and motivated well. The research described here seems to be a reasonable first step towards this goal, with the caveat that some parameters are underspecified or non-standard. My primary comments have to do with the presentation of this work. There are some details missing that would be required to replicate this study, and the text does not provide enough information to understand the greater context of this work in the literature on spatial hearing.

I can guess why the stimulus parameters tested here were chosen – e.g., level rove to avoid reliance on a loudness cue and filtering to evaluate the relative roles of ITD and ILD – but I think readers would benefit from an explicit discussion of those parameters, including references to published work documenting those effects in other populations.

If I am following correctly, the full bandwidth and lowpass filtered stimuli were interleaved within a block of trials. If that is the case, then pre-trial uncertainty regarding spectral content could theoretically have interfered with the use of spectral shape as a cue to location. That seems like a point for discussion.

Detailed comments follow.

Line 108: These factors would introduce frequency-specific attenuation, but they wouldn’t increase or decrease the frequency of a sound. This paragraph was challenging for me to understand because the phrase “frequency intensity changes” was initially confusing. I would have found this easier to read if it had instead used the phrase “spectral shaping”.

Line 119: It is not clear how cognition relates here. Should this be “recognition”?

Line 121: Unilateral hearing loss does not always eliminate access to sound in the affected ear. Sometimes it just reduces access to sound or degrades the quality of that sound.

Page 6, middle: It is not clear what units are used for defining pure-tone thresholds. If those values are in dB HL, then the normal-hearing controls don’t really have normal hearing in the traditional sense. Demographic information should also be provided for the NH group.

Page 7, bottom: The position and selection of loudspeakers is not clear at this point in the text. Why was the speaker with the “smallest noise out of the three” the one that was selected?

Line 170: It is not clear what the “reflex within its envelope” means.

Page 8, middle: I got very confused about the various patterns – how they were characterized or used.

Line 214: The causal structure of this sentence does not make sense to me. Unless I am missing something, the number of presentations does not affect the number of different stimuli.

Line 251: Is this right -- the maximum number correct for each speaker and center is 21? I understood that there were 2 repetitions at each of 3 levels for each of 7 listeners (2*3*7 = 42).

Line 253-254: This sentence is difficult to parse. I think you mean that performance was best at 0° and decreased as the stimulus deviated from midline.

Line 287: Consider putting information about the normal control group in a separate paragraph, for clarity.

Line 318-319: It wasn’t clear to me how this numbering scheme affected analysis of results, which were evaluated in degrees (I think).

Line 359: The number of discrepancies is only informative in the context of the total number of trials. Consider reporting the percent.

Line 369-370: I don’t understand how this topic sentence relates to the remainder of the paragraph.

Line 383: It does not seem accurate to say that early reflections compromise the precedence effect. It might be more accurate to say that the precedence effect is stronger for longer delays.

Line 397: I may have missed it, but I don’t think this was discussed in the results.

Line 422: This is likely to be true, but I don’t think it is accurate to say that this study showed effects of using sound-absorbing materials.

Figure 1: This figure is not needed and potentially confusing, since there isn’t really an intervention in the conventional sense.

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If you choose “no”, your identity will remain anonymous but your review may still be made public.

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Reviewer #1: Yes:  Camille Bordeau

Reviewer #2: No

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<div>PONE-D-25-14950R1-->-->Establishing standardized conditions for clinically available sound-localization tests: A multicenter approach-->-->PLOS ONE

Dear Dr. Yoshida,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Your revised manuscript has been reviewed by original Reviewer #1 and myself, as Reviewer #2 was unavailable at this time. I agree with Reviewer #1 that the review comments have been largely addressed. However, as you will see below, Reviewer #1 pointed out a few remaining minor issues which I invite you to address.

Please submit your revised manuscript by Jul 18 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:-->

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

-->If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Patrick Bruns

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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Reviewers' comments:

Reviewer's Responses to Questions

-->Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.-->

Reviewer #1: (No Response)

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-->2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. -->

Reviewer #1: Yes

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-->3. Has the statistical analysis been performed appropriately and rigorously? -->

Reviewer #1: Yes

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-->4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.-->

Reviewer #1: Yes

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-->5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.-->

Reviewer #1: Yes

**********

-->6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)-->

Reviewer #1: Dear authors,

Thank you for having carefully adressed my comments. I have revised your new submission. I think the manuscript clarity has been improved and the methodology is clearer.

I still would like you to adress two points, linked to my previous 1) and 4) comments.

1) The correction of data availability does not appear in the new submitted manuscript (“the author(s) received no specific funding for this work “ is still mentioned).

4) lines 97-102 : Thank you for the references on poorer localization performance in individuals with UHL, and for the correction of “cognition” into “recognition”. I still do not think there is enough clarity regarding the recognition performance. It would be clearer if you mention the task you are referring to. For instance, if you are referring to speech recognition in noise, please mention a reference for that.

Thank you.

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-->7. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy .-->

Reviewer #1: Yes:  Camille Bordeau

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[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/ . PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org . Please note that Supporting Information files do not need this step.-->

Establishing standardized conditions for clinically available sound-localization tests: A multicenter approach

PONE-D-25-14950R2

Dear Dr. Yoshida,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager®  and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Patrick Bruns

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Thank you for addressing the remaining reviewer comments, I am now happy to accept the manuscript for publication.

Reviewers' comments: