(Thinking cap in operation)

The technique is the same used in transcranial magnetic stimulation (TMS), which has been studied on a more extensive basis for relief of depression, migraines and sleeplessness.

Science fiction authors (and audiences) have been fascinated for generations with the idea of helmets that bestow remarkable abilities.

In his 1937 short story Brain Control, Dave Cummins writes about a brain control helmet that delivers automatic reversed memory:

"...I merely lived through the five minutes before I entered this office, in reverse order; everything happened backward. .."

The doctor was pleased. "Evidently my process worked perfectly. I call it automatic reversed memory. By sending the proper electric currents through that helmet I reverse the electrical action of the nerve cells in the brain and produce this reversed memory... as real as actual experience."

"That helmet I have devised has a great number of small metal plates inside which I pick up the impulses from the various parts of the brain. They pass through the wires to my instruments and their beats, frequencies, and potentials are recorded..."

In his 1938 short story Easy Money, Edmund Hamilton writes about the control helmet:

"...our forefathers originated Control. It is a device to make certain that everyone has the same mental attitude on important questions. The wisest of our race is always the Controller. He wears the sacred Control helmet, the supreme achievement of our science, which amplifies and broadcasts the neuro-electric currents of his brain as a powerful vibration that affects every other human brain, setting up the same currents, the same basic ideas, in them all."

In his 1957 story Cities in Flight, James Blish uses a special helmet (plus gray gas of unspecified composition) to enhance learning, creating accelerated schooling:

They conducted you to your couch and helped you to fit over your head a bright metal helmet which had inside it what seemed to be hundreds of tiny, extremely sharp points which bit into your scalp just enought to make you nervous, but without enough pressure to break the skin. Once this gadget, which was called a toposcope, was adjusted to their satisfaction, the monitors left, and the room began to fill with the gray gas.

This gas was like a fog, except that it was dry and faintly aromatic... it made it impossible to see the rest of the room until the session was over, when it was sucked out with a subdued roar of blowers...

...the torrent of facts that came from the memory cells of the City Fathers into the prickly helmet was overwhelming and merciless.

More recent examples from sf movies abound.

(From Forbidden Planet 1956)

In the film Forbidden Planet, Professor Morbius gains amazing Krell secrets from brief helmet sessions.

In the classic Trek episode Spock's Brain, Dr. McCoy gains centuries of medical knowledge in a single episode.

(McCoy goes to super advanced alien med school)