Mixed Signals and Interspecies Variation in the Plasticity of Adult Mammal Brains
, Marco Ghibaudi 1,2,†,‡, Alessandro Zanone 1, Valentina Cerrato 1,3, Chet C. Sherwood 4 and Luca Bonfanti 1,2,*
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsI enjoyed reading this review, which takes a comparative approach to neurogenesis across species. I found the strengths to be an exhaustive coverage of the literature and good detail in explaining important concepts and highlighting areas for future study and clarification. I would have liked to see a few more usual species included (I believe bats are another controversial example) and perhaps consideration of the extensive ongoing neurogenesis in non-mammalian vertebrates (particularly in relation to evolutionary significance and trade-offs as I mention below).
The main weakness was that the evolutionary aspect was mentioned but never fully explained: there is mention of "trade-offs" but these trade offs are not actually identified or discussed in any meaningful way. This (anticipated) content was my main reason for accepting to review the article as I was very interested in finding out more about the tradeoffs that are thought to be involved in the transition/balance between conventional neurogenesis and maturation of dormant precursors. Unfortunately I had to turn to other articles to be educated in these concepts as the coverage here was superficial.
I encourage the authors either to develop this aspect of their review (potentially tightening up the language to reduce the word count overall) or to change the title to make it more reflective of the focus of this review, which is currently identifying the molecular and cellular signals/markers that can help identify different forms of neurogenesis across species.
Comments on the Quality of English LanguageThe language is fluent and understandable but contains grammatical errors that should be corrected
Author Response
Reviewer 1
- I enjoyed reading this review, which takes a comparative approach to neurogenesis across species. I found the strengths to be an exhaustive coverage of the literature and good detail in explaining important concepts and highlighting areas for future study and clarification.
ANSWER: We thank the Reviewer for appreciating our work.
- I would have liked to see a few more usual species included (I believe bats are another controversial example) and perhaps consideration of the extensive ongoing neurogenesis in non-mammalian vertebrates (particularly in relation to evolutionary significance and trade-offs as I mention below).
ANSWER: We were intended to restrict the topic to mammals (and we have now specified it in the Title).
Bats were not considered because the available data are mostly focused on hippocampus and sparse among different species.
- The main weakness was that the evolutionary aspect was mentioned but never fully explained: there is mention of "trade-offs" but these trade offs are not actually identified or discussed in any meaningful way. This (anticipated) content was my main reason for accepting to review the article as I was very interested in finding out more about the tradeoffs that are thought to be involved in the transition/balance between conventional neurogenesis and maturation of dormant precursors. Unfortunately I had to turn to other articles to be educated in these concepts as the coverage here was superficial.
I encourage the authors either to develop this aspect of their review (potentially tightening up the language to reduce the word count overall) or to change the title to make it more reflective of the focus of this review, which is currently identifying the molecular and cellular signals/markers that can help identify different forms of neurogenesis across species.
ANSWER: We understand the point and indeed the problem was in the Title. The topic of the review article is on the elements of confusion that bring complexity in the field of mammalian brain plasticity, focusing on two main points: i) the rather unspecific markers, and ii) the marked interspecies variations.
Hence, we followed the Reviewer’s advice to change the Title (by replacing “trade-off” with “interspecies variations”).
Again, the main goal of the review article is not to go deeper in the evolutionary aspects (the readers are referred to previous review articles (e.g. [Ref. 9 and 123] and reviews from other authors), but to underline the elements causing confusion in the field and sometimes controversies (some of them being linked to evolutionary aspects).
Anyway, we took advantage of the Reviewer’s comment to expand a little and clarify the concept of trade-off applied to brain plasticity. Some parts dealing with evolution were further refined during the English editing, hoping to be clearer.
Reviewer 2 Report
Comments and Suggestions for AuthorsThis is an extremely comprehensive review regarding the differences in neurogenesis and plasticity between a large number of species. It is exceptionally well written, easy to follow and brings together a wealth of knowledge from a large number of sources. The figures are well presented, easy to follow and add to the text. The authors should be congratulated for an excellent and interesting review.
I have only very minor suggestions that do not detract from the excellent review.
Figure 1A: Stem cell to neuroblast and no mention of progenitor cells which is then discussed in subsequent text. Not essential to include but it could be added.
It is not clear what the "NON CANONICAL" text belongs to in Fig 1B.
Perhaps a key for the different cell types in Figure 3 would improve readability. for example the grey cells, red cells and the blue dotted cells.
In Figure 7 perhaps the numbers for body weight and gyrification index could be different colours to make it easier to distinguish.
Figure 8: In "trade-off hypothesis" Hypothesis is mis-spelt. The first sentence in Fig.8 caption could have the grammar improved.
Author Response
Reviewer 2
This is an extremely comprehensive review regarding the differences in neurogenesis and plasticity between a large number of species. It is exceptionally well written, easy to follow and brings together a wealth of knowledge from a large number of sources. The figures are well presented, easy to follow and add to the text. The authors should be congratulated for an excellent and interesting review.
ANSWER: We thank the Reviewer for appreciating our work.
I have only very minor suggestions that do not detract from the excellent review.
- Figure 1A: Stem cell to neuroblast and no mention of progenitor cells which is then discussed in subsequent text. Not essential to include but it could be added.
ANSWER: Yes. We added the progenitor stage.
- It is not clear what the "NON CANONICAL" text belongs to in Fig 1B.
ANSWER: Yes, It was NON-CANONICAL NEUROGENESIS. We added it.
- Perhaps a key for the different cell types in Figure 3 would improve readability. for example the grey cells, red cells and the blue dotted cells.
ANSWER: A legend was created at the bottom of the Figure.
- In Figure 7 perhaps the numbers for body weight and gyrification index could be different colours to make it easier to distinguish.
ANSWER: Done.
- Figure 8: In "trade-off hypothesis" Hypothesis is mis-spelt. The first sentence in Fig.8 caption could have the grammar improved.
ANSWER: Both requests have been done.
Overall, a new version of Figures 1, 3, 7, 8, was provided (already inserted in the manuscript text).
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThank you - these small changes made the review much clearer and helped me understand the goals of the authors.
Please complete an English check to correct grammatical errors and clumsy expression
Comments on the Quality of English LanguageThe language is fluent and understandable but contains grammatical errors that should be corrected
Author Response
The English of the entire manuscript has been revised through the MDPI service
