I find this an interesting story and it relates somewhat to the workings of computers....
Our computer's hard disk contains many files, scattered all over the place. The key to the precise location of each file is contained in a special data table that is separate from the files themselves. In effect, when we want to open a file, the computer goes to the phone directory [that table], looks up the name, and 'rings' the number - goes to the location where it is held.
When we delete a file, the information is not lost immediately. The entry in the table is simply changed so it does not show in the phone directory - in practice it becomes ex-directory to all except specialist rescue programs. But the data is still on the disk, at least until it is replaced by something else, partially, or completely.
To try to get back to a 'deleted' file, we can use specialist software. It may or it may not work, depending how recently the file was deleted, and also whether some of the file space has already been used.
If in this research they have found a way of providing a specialist program for the human brain that enables it to identify where this or that memory is - or was - then it would be good.
... just awaiting a PC specialist who will correct some of the above, though I believe it is broadly correct - we used similar techniques on mainframe computers in the 1970s to regain lost files.