Here is a basic description of the 5 regions of the brain and what functions they are responsible for.

With the checklist you may get a better understanding of what region(s) are affected.  Usually a brain injury is not isolated.  A blow to the front of the head will cause frontal and occipital injury and a blow to the side of the head will injure both sides.  The reason for this is that the brain floats suspended in a cerebal spinal fluid and when one side of the head is struck the brain bounces off that side and then bounces off the opposing side thusly causing complications all around the brain.

Frontal Lobe

A New Study Linking Frontal Lobe Brain Injury to ability to holding down a job. 

Initiation                                                        Smelll

Planning/anticipation                                   Motor Planning

Follow through                                              Personality

Impulsivity                                                     Emotional (Affect)

Judgement                                                   Speaking (word Finding)

Reasoning                                                    Integration of thought and emotion

Abstract Thinking                                         Self Monitoring

Temporal Lobe

Memory

Hearing

Understanding Language

Parietal Lobe  

Intellect

Sense of touch

Differentiation: Size,Shape color

Spatial Perception

Visual Perception

Occipital Lobe

Vision

Cerebellum

Balance

Coordination

Note: The Parietal and Temporal Lobes have a left and right side.