This episode may have been inspired by the University of Texas clock tower shootings (said to be the beginning of America's era of mass shootings) which occurred on 1 August, 1966, five months before this episode aired. The shooter in that incident was also ex-military, but was struggling with violent impulses and shooting fantasies years before he finally lost it. A tumor was discovered on his brain upon autopsy (Wikipedia). Leslie Nielsen's character in this episode seems to be suffering from post-traumatic stress which began to show with outbursts of anger some months before his breakdown.
In his conversation with Ben, Dr. Evans mentions a new style of mental hospital in Washington, DC created by Dorothea Dix (1802-1887), who was in charge of Union Army nurses during the Civil War before resuming the task of reforming the treatment of the mentally ill.