PONE-D-19-31125

Serotonin improves behavioral contrast sensitivity of freely moving rats

PLOS ONE

Dear Dr. Shimegi,

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PLOS ONE

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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: Partly

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

Reviewer #1: Yes

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Reviewer #1: Yes

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

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Reviewer #1: Yes

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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 author tested the contract sensitivity of rats before and after intraperitoneal injection of serotonin re-uptake inhibitor in 2AFC-VDT behavior task. Contrast sensitivity was first found to be higher in rats after intraperitoneal injection of fluoxetine (FLX) than before in the condition on optimal special frequency of 0.1. The authors therefore concluded that endogenous 5-HT release in the brain can improve visual detectability. However, the function of FLX to inhibit 5-HTT is not directly related to the release of 5-HT, and FLX directly acts on the 5-HT receptor (Liang Peng et al Current Neuropharmacology 2014). It is better to improve the accuracy of conclusion in this study. Overall, this study suggests that FLX improves CS in rats which will provide more reference evidence for studying the relationship between 5-HT and visual information processing.

Some important points provided below might improve the accuracy of the conclusions.

1. Discuss the relationship between FLX, 5-HT and 5-HT receptors (Liang Peng et al. Current Neuropharmacology. 2014), which will help to clarify the relationship between 5-HT and visual information processing.

2. The conclusion in line 208 states that " serotonin endogenously released from the dorsal raphe nucleus...". There is no direct evidence in this article providing that 5-HT derived from DR functioning in CS , besides the major serotonergic neurons also exist in MR area (Iskra Pollak Dorocic et al. Neuron. 2014). Discussion of the serotonergic neurons projecting areas might help to improve the accuracy of the conclusion.

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Reviewer #1: No

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Serotonin improves behavioral contrast sensitivity of freely moving rats

PONE-D-19-31125R1

Dear Dr. Shimegi,

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

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Judith Homberg

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 #1: All comments have been addressed

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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: Partly

**********

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

Reviewer #1: 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 #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: (No Response)

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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: Chao Guo