Automatic exposure control (AEC) is effective at reducing potentially harmful radiation doses without sacrificing image quality for many types of computed tomography (CT) scans. However, there is a need for more information regarding the use of AEC for CT head scans. This study was conducted at Johnson County Community Hospital in Mountain City, TN. Preexisting adult CT head scans (n)60 were randomly selected to form 2 stratified samples, (n)30 each. One sample used a standard protocol, and the other used a protocol with a mA-modulated AEC system, Siemens CARE Dose 4D. Causal-comparative analyses were conducted, and it was determined that AEC was effective at maintaining subjective image quality while reducing radiation doses an average of 38% for adult CT head scans. It was concluded that using AEC was an effective tool to optimize radiation doses for adult CT head scans in one particular setting, but more research on this topic is needed.