pretty much my experience too. I never got that good at dual n-back (4 I think, and only if I was well-rested) and my IQ didn't improve, but I did find an incre

pretty much my experience too. I never got that good at dual n-back (4 I think, and only if I was well-rested) and my IQ didn't improve, but I did find an increase in the ability to relate recent events to the present and keep track of recent events. For example, during meetings I was much more able to recite back to someone things they had said earlier in the meeting in the context of what we were presently discussing.