As to be expected from a well known expert of the amygdale, this paper provides a very condensed but yet easily accessible account of our current insights in what the amygdale is all about. The evident problem of different terminologies is introduced and appropriate references are provided for those who want more detailed information. I have only a few suggestions to further improve the already high quality of this entry. When mentioning the proposed subdivision into a stratial versus a cortical component in the amygdala, it may be of use to relate that to the remark that “The scheme of inputs and connections just described applies to the neurons of the basolateral complex moreso than to neurons within the corticomedial group and the subsequent sentence on the projections of the central nucleus being inhibitory, which is similar to those of the basal ganglia. Cortical connectivity in general is excitatory. May be a reference to entries on basal ganglia and cortex can be added under the heading “See Also”. May I suggest to provide a little more detail on the role of the amygdale in the regulation or modulation of a variety of cognitive functions. The example of amygdale activation leading to release or hormones and the specific example of glucocorticoid release may give the wrong impression that there is no role for the widespread direct projections of the amygdale to the cortex. There is ample evidence that motivational components of for example attentional processing or memory do not critically depend on the release of hormones but may be the result of such direct connections and that there might be two different time domains, a fast amygdale influence mediated by neuronal connectivity and a slower, hormonal mediated effect (see for example Richter-Levin 2004, Neuroscientist 10, 31 for a review). Also the possible relevance of cortical processes onto amygdale processing might be mentioned. An obvious question that may come up when people access this entry is whether anything is known about left and right differences and sex differences with respect to amygdala functions. A short paragraph should be sufficient to point readers into the right direction and I am sure that the author has all the relevant information to add this.
Minor suggestions: • The phrase: “The scheme of inputs and conections” might be better phrased “The scheme of connections” since inputs are part of the connections. • The sentence following the statement about the inhibitory nature of the central nucleus output is unclear. Suggest to change; for example: Excitation of neurons in the central nucleus leads to inhibition of target cells, while inhibition of these projection neurons gives rise to an increased output of the target neurons. • Clarify that the instrumental components of fear conditioning are the newly acquired behaviors to avoid the shock.
This is a well written, accessible and comprehensive introduction to the amygdala. The only criticism I have is in regard the inclusion of the molecular figure. The figure is not well explained, and the article does not really benefit from its inclusion given that the focus of the article is more on a historical and systems level approach.
Author Comment: Dear Reviewer 2. Thanks for the comments. I would like to keep the molecular figure because it is in the Functions part of the article, and it is important for readers to realize that the functions of the amygdala have been related to molecular mechanissms. I will try to add a few sentences in the text to make it more acceptable.