Characteristic changes in EEG spectral powers of patients with opioid-use disorder as compared with those with methamphetamine- and alcohol-use disorders

Christopher Minnerly; Ibrahim M. Shokry; William To; John J. Callanan; Rui Tao

doi:10.1371/journal.pone.0248794

Peer Review History

Original SubmissionFebruary 28, 2021
26 Apr 2021 Decision Letter - Wajid Mumtaz, Editor PONE-D-21-06684 Characteristic changes in EEG spectral powers of patients with opioid-use disorder as compared with those with methamphetamine- and alcohol-use disorders PLOS ONE Dear Dr. Rui Tao, 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. Please submit your revised manuscript by Jun 10 2021 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. 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Please do not edit.] 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 ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: No ****** 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: Yes Reviewer #2: No ****** 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: Yes Reviewer #2: Yes ****** 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: This is a well designed and intriguing study. I think the results would be even more relevant and valuable if there was an analysis done of the EEG spectra in wakefulness vs REM sleep vs NREM sleep. At least there should be a comparison between wakefulness and sleep as alcohol, opiates and stimulants can affect neurophysiological function in sleep differently than they do in wakefulness Reviewer #2: The topic of the paper is interesting. However, the statistical analysis should be improved. Comments are listed below. 1. Data availability: Data location has not been listed. As such, data is not available. 2. Data collection/preprocessing: Only 10-minutes of resting state EEG sampled at 256 Hz is analyzed. Were the data collected only once? Did the subjects return for multiple recordings? Were their tasks performed? A single recording at resting-state is better than no recording, but the conclusions may be limited by one-time recording due to non-stationary behavior of the brain signals. Were the powerline noise removed from the data? 3. Selection of Subjects: Out of 350 Opioid, 450 Alcohol and 100 Meth, selection of only about 20 subjects per group seems to be limited by the control group. This is the main weakness of the paper. The authors can divide the A, M and O groups to smaller groups of 20 subjects and see if an average of all subgroups match with the current conclusions of the paper. This may increase statistical significance of the results. 4. While absolute band powers have been analyzed, it may be useful to analyze relative band powers. These have played a role in discriminating two classes of EEG signals such as pre-ictal and inter-ictal in epilepsy. Relative band powers can be calcluated by dividing every subjects band power by the total power spectral density. See for example, Z. Zhang et al, "Low-Complexity Seizure Prediction From iEEG/sEEG using Spectral Power and Ratios of Spectral Power," 2016 5. While the statistical behavior is useful and should be published, the community has focused on binary classification. This could be considered as future work. As one example of such classification, the authors may refer to: B. Sen et al., "Sub-Graph Entropy based Network Approaches for Classifying Adolescent Obsessive-Compulsive Disorder from Resting-State Functional MRI," 2020 ****** 6. 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:** Hrayr Attarian Reviewer #2: No [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. https://doi.org/10.1371/journal.pone.0248794.r001
Revision 1
14 Jun 2021 Author Response Response to Dr. Hrayr Attarian Q5. ……. the results would be even more relevant and valuable if there was an analysis done of the EEG spectra in wakefulness vs REM sleep vs NREM sleep. At least there should be a comparison between wakefulness and sleep as alcohol, opiates and stimulants can affect neurophysiological function in sleep differently than they do in wakefulness Reply: We totally agree with the importance to show the difference between wakefulness and sleep in patients with opioid use disorder in contrast to those with alcohol or stimulant use disorders. However, there is no sleep data available for us. Therefore, we could not conduct the comparative study. The comments are very valuable for future direction. The retrospective EEG data used in the present studies refers only at the eye-closed (wakeful) state. ==================================================== Response to Reviewer #2: Q6. Data availability: Data location has not been listed. As such, data is not available. Reply: Thanks for the comment. In this revision, every raw data was attached to supplementary sections S1-S5. Q7. ……. Were the data collected only once? Did the subjects return for multiple recordings? Reply: Only one time of data prior to rehab treatment was approved to be used in the present study. Patients did return after rehab treatment. However, data after rehab treatment were not approved for disclosure. Q8. Were their tasks performed? Reply: No tasks performed. The eye closed, and subject seated calmly without any activity or movement. Q9……Were the powerline noise removed from the data? Reply: Yes, it was removed. Additionally, artifacts (non-EEG) were also removed from the data, as described on pg6 line 149-151 “…….. raw data was edited using the editing tool within the NeuroGuide software to remove physical artifacts (including eye movement, jaw movement, and gross movement)……” Q10. Out of 350 Opioid, 450 Alcohol and 100 Meth, selection of only about 20 subjects per group seems to be limited by the control group. This is the main weakness of the paper. Reply: We appreciate the reviewer’s concern. However, most patients in our database were found to be multi-drug users. Therefore, most of them should be excluded from the study. Patients with neurodegenerative diseases (e.g., PD and MD) should also be excluded. Only a few dozen patients met the criteria for meaningful retrospective data analysis. Our primary goal in this study was to characterize EEG in patients with opioid use disorder (OUD). For this reason, 20 OUD patients were compared with sex- and age-matched healthy control. We believe that readers might feel more interested in knowing the difference in EEG between OUD and stimulants (MUD) or alcohol (AUD). Therefore, we compared OUD with MUD or AUD. Although we could not get sex- and age-matched (stimulant/MUD or alcohol/AUD) data, we think the results were still valuable, even though, we had only 15 MUD patients. Q11. The authors can divide the A, M and O groups to smaller groups of 20 subjects and see if an average of all subgroups match with the current conclusions of the paper. This may increase statistical significance of the results. Reply: We conducted a statistical analysis with a smaller number of cases as suggested to see if statistical significance of the results would increase or not. Because we had only 15 MUD cases, we had to remove 5 cases out of the CTL (C4, C7, C14, C12, and C15), 5 from the opioids (O7, O15, O17, O18, and O34), and 7 out of the alcohol (A3, A8, A19, A25, A27, and A28) to have 15 cases per every group. All groups were analyzed. Please see the table below. CTL (N=15) OUD (N=15) MUD (N=15) AUD (N=15) Age (years) 29 (�8) 30 (�9) 29 (�8) 33 (�6) Sex (M/F) 8/7 8/7 11/4 10/5 Duration of substances used (years) 0 6 (�4) 5 (�3) 6 (�7) We started to re-examine delta/� powers presented in fig 3B. The ANOVA was used to analyze 4 groups of absolute delta/� values of the F3 electrode, revealing significant difference between 4 groups, showing F(3,56) =3.203, P =0.03. We also analyzed the percentage values and had the same results. We next conducted post-hoc test analysis revealing that changes in opioids/OUD, stimulants/MUD or alcohol/OUD were not different from CTL (see figure below). The statistical significance of the results decreased. Given that increases in numbers of cases would improve the significance of statistical analysis, we decided to keep the original analysis (i.e., 20 cases in CTL; 20/opioid, 15/stimulants, and 23/alcohol) showing F(3,74) =6.07, P). =0.0009. To clarify the question for readers, we added three new sentences on pg11 line251-254, stating that ‘The normalized data appear to have the same response pattern as……absolute value’ In addition to F3, all 19 electrodes were re-examined using smaller numbers as shown below. Similarly, figures C’-G’ displayed the same tendency as figure 3C-G in the manuscript although case numbers reduced. However, no electrode was found to have statistical significance. For this reason, we kept the case numbers in the manuscript as was. Q12. While absolute band powers have been analyzed, it may be useful to analyze relative band powers. These have played a role in discriminating two classes of EEG signals such as pre-ictal and inter-ictal in epilepsy. Relative band powers can be calculated by dividing every subjects band power by the total power spectral density. See for example, Z. Zhang et al, "Low-Complexity Seizure Prediction From iEEG/sEEG using Spectral Power and Ratios of Spectral Power," 2016. Reply: This is also a good point raised by the reviewer. Analysis of absolute values could be simple but potentially create data bias due to individual differences, which was correctly emphasized by Zhang et al 2016. To do this, EEG changes in seizure attack could be normalized to the pre-seizure EEG powers, which is a perfect approach for the seizure analysis. Regarding our patients with substance use disorders (SUD), pre-SUD data were not available in the database. Therefore, we could not calculate changes relative to pre-SUD levels when they were still mentally healthy. Fortunately, there were 20 healthy CTL included in the study. Those CTL data could be used as pre-SUD data. Specifically, in our manuscript, relative changes (% CTL) were determined with CTL EEG powers, displayed in fig 3A-G, and also supplementary S2-5. In other words, our data analysis in the manuscript considered both absolute and relative values. We found that statistical analyses over relative changes were the same as the absolute values, indicating no difference. Absolute values were used in figures 4-8 for a direct comparison of our results with other labs (see details on pg11 line251-254) Alternatively, relative powers of individual/group electrodes can be divided by the total powers of all 19 electrodes. Please note that the total powers presented in fig 8, showed significant difference in EEG between users. Although we haven’t divided individual/group electrodes by the total powers, we will include this idea in future analysis. Q13. While the statistical behavior is useful and should be published, the community has focused on binary classification. This could be considered as future work. As one example of such classification, the authors may refer to: B. Sen et al., "Sub-Graph Entropy based Network Approaches for Classifying Adolescent Obsessive-Compulsive Disorder from Resting-State Functional MRI," 2020. Reply: We appreciate this suggestion. Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0248794.r002
16 Jul 2021 Decision Letter - Wajid Mumtaz, Editor PONE-D-21-06684R1 Characteristic changes in EEG spectral powers of patients with opioid-use disorder as compared with those with methamphetamine- and alcohol-use disorders PLOS ONE Dear Dr. Rui Tao, 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. Please submit your revised manuscript by Aug 30 2021 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: http://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, Wajid Mumtaz 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. [Note: HTML markup is below. Please do not edit.] 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: All comments have been addressed Reviewer #2: (No Response) ******** 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 Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: N/A ****** 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 Reviewer #2: Yes ****** 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 Reviewer #2: 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: Thank you for thoroughly addressing all the reviewer concerns. I have no further comments about this paper Reviewer #2: Statements from the response should be included in main part of the paper. future directions with respect to features and classifiers should be pointed out. ****** 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:** Hrayr Attarian Reviewer #2: No [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. https://doi.org/10.1371/journal.pone.0248794.r003
Revision 2
11 Aug 2021 Author Response Response to editorial requirement Q1. 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. Reply: The references cited in the manuscript has been reviewed in a one to one manner. Specifically, the references were copy-pasted to the NIH PUBMED website. There was no information indicating retraction of references cited in the manuscript. Response to reviewer #2 Q2. …the response should be included in main part of the paper. Future study direction with respect features and classifiers should be pointed out Reply: the response has been included into the context of the manuscript. Details are as follows. Questions and concerns Pages, lines and response located in the manuscript Were the data collected only once? Did the subjects return for multiple recordings? on pg6 lines 150-151 “Only one time of data prior to rehab treatment was approved by the IRAs to be used in the present study” “Were their tasks performed?” on pg6 lines 135-136 “Eyes closed, and subject seated calmly without any activity or movement” “Were the powerline noise removed from the data? on pg6 line 152-154 “…….. raw data was edited using the editing tool within the NeuroGuide software to remove physical artifacts (including eye movement, jaw movement, and gross movement)… The authors can divide the A, M and O groups to smaller groups of 20 subjects and see if an average of all subgroups match with the current conclusions of the paper. This may increase statistical significance of the results On pg15-16 ……(see details in fig 3, and also supplementary S1-S4). One explanation for such failure could be that the retrospective analysis was not designed as a one-to-one matched case control study. It was likely to be that the statistical power would be increased if the subgroups were matched. To test such possibility, subjects were reduced to 15 cases/subgroup for the age- and sex-matched design. Delta/� powers presented in fig 3B were re-examined with the ANOVA, revealing significant difference between 4 groups, F(3,56) =3.203, P =0.03. However, the post-hoc analysis revealed that changes in OUD, MUD or AUD were not different from CTL, suggesting the one-to-one matched design could not fully explain the failure at statistical analysis. Alternatively, a single electrode covered only small brain areas in terms of EEG spatial sizes and thus relatively small numbers of neurons affected…. While absolute band powers have been analyzed, it may be useful to analyze relative band powers. These have played a role in discriminating two classes of EEG signals such as pre-ictal and inter-ictal in epilepsy. Relative band powers can be calculated by dividing every subjects band power by the total power spectral density. See for example, Z. Zhang et al, "Low-Complexity Seizure Prediction From iEEG/sEEG using Spectral Power and Ratios of Spectral Power," 2016. On pg 10 line247-pg11 line 253 Next, the EEG waves were transformed into amplitude powers expressed as µV2, as shown in the left panel of Fig 3B. The difference in delta/� amplitude powers was statistically significant [F(3, 74) =6.07, P =0.0009]. However, post-hoc analysis indicates that only OUD, but not MUD or AUD, reached statistical significance difference from the CTL. Analysis of absolute values could be simple but potentially create data bias due to individual differences. To minimize such possibility, data were normalized into %CTL. While the statistical behavior is useful and should be published, the community has focused on binary classification. This could be considered as future work. As one example of such classification, the authors may refer to: B. Sen et al., "Sub-Graph Entropy based Network Approaches for Classifying Adolescent Obsessive-Compulsive Disorder from Resting-State Functional MRI," 2020. On pg19, line 496-498 ….Despite such importance, it cannot exclude the possibility of bias, so other biomarkers and binary classification are needed to be included in the future study by which the conclusion can be alternatively corroborated… Attachments Attachment Submitted filename: Reponse to Reviewers.docx https://doi.org/10.1371/journal.pone.0248794.r004
26 Aug 2021 Decision Letter - Wajid Mumtaz, Editor Characteristic changes in EEG spectral powers of patients with opioid-use disorder as compared with those with methamphetamine- and alcohol-use disorders PONE-D-21-06684R2 Dear Dr. Rui Tao, 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 for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, 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, Wajid Mumtaz Academic Editor PLOS ONE Additional Editor Comments (optional): 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 #2: All comments have been addressed ******** 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 #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #2: Yes ****** 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 #2: Yes ****** 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 #2: 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 #2: Paper is acceptable. I would still suggest to cite the references suggested in the initial review as directions for future work. ****** 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 #2: No https://doi.org/10.1371/journal.pone.0248794.r005
Formally Accepted
31 Aug 2021 Acceptance Letter - Wajid Mumtaz, Editor PONE-D-21-06684R2 Characteristic changes in EEG spectral powers of patients with opioid-use disorder as compared with those with methamphetamine- and alcohol-use disorders Dear Dr. Tao: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. 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. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Wajid Mumtaz Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0248794.r006

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