Unresponsive trackpad and keyboard MBP 13" I7 Core Chip 2011

I once thought that my MBP 13" with I7 Core chip (2009) edition, was somewhat without sufficient memory, due to some spinning beach balls etc...witht the 4GB ram it came with. I took it to TekServe in NYC and asked about this. The technician said that the memory was not sufficient by what I was asking the computer to do....Multiple open windows, multiple documents etc... I bought 12 GB of extra memory and plugged it in.

While the spinning balls have halted somewhat, the issue I have been having with the Lion OSX and now, even worse, with a Mountain Lion update is what I call an unresponsible keyboard and trackpad. It takes more than a couple of keystrokes and taps on the trackpad in order to get the system to react. I turned off any sort of energy management software etc.... and still does this.

Even when I am browsing, when I stop using the keyboard for a couple of seconds, it goes back to its unreactive state.

So, I am wondering what might be the culprit.

A defective keyboard and trackpad?

A defective connection between the keyboard and the motherboard?

A faulty hard drive that simply goes to sleep?

A faulty motherboard?

The worst part of the entire ordeal is that even my 2009 15" MBP with 8 GB Ram and slower chip is more flawless and smoother than the MBP 13" I7. I wonder what might be the problem.