not sure to understand what you ask
the latest version of kernel in synaptic is 188.8.131.52
the kernel is not updated automatically because it doesn't offer conflicts to use a older kernel with newer apps
also, a newer kernel could offer you problems with some of your hardware, this is not the rule but can it happen sometimes
if you want to test a new kernel all you have to do is search for it in synaptic and add it, you can have multiple kernels if you want, i have installed simultaneously 4 but afik you can have more
the kernel you install can be the basic, bfs, pae, a64 and pae.bfs
if your cpu is a recent model from intel and you have more than 4 gbs of ram, pae or pae.bfs are good options
a64 is good for atom and amd 64bit capable cpus, just like yours!