Number of presynaptic inputs per cell in primary visual cortex I have been digging in the literature lately, but I haven't found a nice answer  with clear cut numbers (avg +- std) to this question:

How many presynaptic inputs receives a pyramidal cell in primary visual cortex (preferably in cat)?

To be a bit more precise here I also would like to know the following details:

Number of inputs in terms of synapses as well as number of presynaptic cells


Depending on the layer the postsynaptic cell resides in
Depending from where the inputs originate (afferent, horizontally recurrent, vertically recurrent etc.)
How many total synapses vs from how many presynaptic cells these originate, i.e. average number of synapses per pre/post cell pair
Depending on distance of presynaptic cells to the postsynaptic one
Depending on type of input, excitatory vs. inhibitory


I highly appreciate if you can direct me to literature listing actual numbers :-)
Very detailed estimates for almost all of your points, for cat, can be found in Binzegger, T., Douglas, R. J., &amp; Martin, K. A. C. (2004). A quantitative map of the circuit of cat primary cortex. Journal of Neuroscience, 24(39), 8441-8453.