Simon conducted the sessions on Barney and Betty separately , so they could not overhear one another 's recollections .
He hypnotized Betty and Barney several times each , and the sessions lasted until June 6 , 1964 .
Simon conducted the sessions on Barney and Barney separately , so they could not overhear one another 's recollections .
He hypnotized Betty and Barney several times each , and the sessions lasted until June 6 , 1964 .