Depiction of the <i>BrainAGE</i> concept.

<p>(A) The model of healthy brain aging is trained with the chronological age and preprocessed structural MRI data of a training sample (left, with an exemplary illustration of the most important voxel locations that were used by the age regression model). Subsequently, the individual brain ages of previously unseen test subjects are estimated, based on their MRI data (blue, picture modified from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0157514#pone.0157514.ref056" target="_blank">56</a>]). (B): The difference between the estimated and chronological age results in the <i>BrainAGE</i> score, indicating abnormal brain aging. [Image reproduced from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0157514#pone.0157514.ref017" target="_blank">17</a>], with permission from Hogrefe Publishing, Bern]