Lync: My Picture
Microsoft Lync shows your picture by default.
Are there any other choices?

3. Try It: Review the Picture Options
Go to Options->Tools->Options.
Click on My Picture.
There are three options for My Picture:

Hide my picture:
Participants will see a silhouette.

Show my picture:
Participants will see your picture.

Edit or Remove picture:
If you click on Edit or Remove, you will prompted to log into Office 365 online so you can revise the picture in your profile.

Keep going...

Microsoft Lync->Options->Tools->Options->My Picture