Response to Reviewers
We have included the text and references according to reviewers suggestions. Additionally, we have included classic and modified penfield maps to better illustrate the homunculus organization pre- and post-amputation of the hand.
I like this article and I think that it summarizes a phenomenon of broad interest. Whenever I talk about cortical reorganization, phantoms come up. I think that the level of discussion and the pints covered are appropriate for this level of article.
I made a few minor changes in the text, in particular I moved a paragraph from the body to the conclusion. I have some specific comments that I didn’t address.
Section on "Remapping"
1) When describing the organization and reorganization of S1 after amputation, I think that a schematic figure showing the normal Penfield homonculus and the reorganized homunculus would be extremely helpful to readers unfamiliar with S1. I would say insert it as Figure 1, referring to it before the current Figure 1.
2) Paragraph 5: The authors refer to axon sprouting and unmasking as possible mechanisms and cite a study by ramachadran and azouli as support for unmasking. I don’t understand how the experiment on cold caloric irrigation shows evidence for unmasking. Please better describe the experiment and its relevance. Also, there is considerable evidence from animal studies for both sprouting (e.g. Florence et al., 1998 ) and synaptic changes (nicely reviewed in Buonomano and Merzenich, 1998). It might be profitable to cite those here, as well.
3) paragraph 6: Define the abbreviation "STS"
References: 4) Provide the full references, including titles, for two abstracts: Ramachandran and Azoulai, 2007 and Ramachandran VS McGeoch D Brang ( 2008).
I liked this article and have only a few minor comments:
1. Intro, para 2: ambiguous citation to SM Anstis. This sounds like he might be the subject rather than the informant.
2. Remapping, para 2: explain who Penfield was, perhaps with ref
3. Remapping, para 2: explain results of MEG study
4. Remapping, para 5: show cellular evidence for axonal sprouting, or tone down e.g. use possibly rather than probably (have changed this)
5. Remapping, para 6: cite evidence for mirror neuron system for touch (Keysers et al 2004, Blakemore et al 2005). Latter half of this para is very speculative. Tone down? There is evidence that some people feel observed touch (Blakemore et al. 2005)