Brand Analytics permissions are located on the global permissions section.  Please follow these steps:

a. On the Seller Central home page hover over the  Settings tab on the top right, click   User Permissions.

b.  Select    Manage Global Permissions next to our user name - Sellers Arena

c. Next, under Performance, select   View on Brand Benefit Eligibility

d.  Under Reports, select  View on Brand Analytics

e. Scroll to the bottom and Click Save Changes