The 2008 Formula 1 world champion had a turbulent 2011 season, and although he won three grands prix, he also had a number of incidents and was outscored by his team-mate Jenson Button, who beat him by three positions in the points standings.
Hamilton said he had made conscious efforts to reduce the level of 'baggage' in his life and develop better communication with his engineers this year.
"Every year you finish the season and you try to analyse what you've been through and what you've done, and try to take away the positives from what you've done," he said. "Then you try to channel those and then improve on the things that you didn't do so well.
"I've always said it's a combination not just of things you do at the track, but it's your personal life out there, time at home, time with friends, those sort of things.
"I've strengthened bridges and relationships with people, not only in my personal life but also in my team. I've been working with the engineers better this year and all of that stuff has just helped.
"I don't have any particular problems going on in my life, or any baggage - and last year I had a big, big sack. Fortunately I've dumped that in the dumpster and it's all good now."
After winning the last grand prix in Hungary, Hamilton is now fourth in the championship, 47 points behind leader Fernando Alonso.