Google+ gives the option of keeping track of all the +1s on Google+ posts. To review your +1s history and make any changes, simply follow the following steps.
[box color=IBOutline]Please note that the following steps are for tracking your +1s on Google+ posts and not for the web content that you +1d outside Google+. The +1s on websites can be viewed and edited via the +1Tab on your Google+ Profile. [/box]
2. Under Apps and Activities, click ‘Manage Apps and Activities’
3. Select ‘Log’
4. You can now view and edit the posts that you’ve +1d.
Clicking on any post will open the post so that you can review it. Selecting the ‘X’ button, as shown in the above screenshot, will delete your +1 as well as remove it from the activity log.