Airbag assemblies are disclosed that can reduce rotational velocity of an occupant's head during a collision event and thereby mitigate traumatic brain injury/head injury to an occupant. An airbag includes a pair of lobes or protrusions to deploy and extend from the rear face of the airbag on either side of the occupant's head to limit rotation of the head. A pair of vertical tethers within an interior of the airbag configure the lobes and contour the rear face to form one or more low fabric tension zones or bubbles. The lobes maintain high fabric tension, similar to a pressurization of a main inflatable chamber of the airbag.