Sims 3 on iMac problem

I bought all the sims 3 games for my iMac. I really do enjoy it more that Sims4 people the community grows up on its own and its more realistic.

Usually about 30 minutes until the game, my character avatar down in the menu options seems to glitch and i get these strange black lines going through it.

There are a few other random glitches but those don't happen all the time. Is there something I can do to fix this? I really don't want to uninstall this game I paid so much for.

Thanks for your help!