Researchers reported, on Wednesday, that a paralyzed man has regained the capacity to walk smoothly using only his thoughts for the first time, owing to two implants that restored the connection between the brain and spinal cord.

The patient Gert-Jan, who did not want to reveal his surname, stated that the breakthrough had given him "a freedom that I did not have" before.

After sustaining spinal cord damage in a cycling accident, the 40-year-old Dutchman has been paralyzed in his legs for more than a decade.

According to research published in the journal Nature, he can now walk "naturally", tackle rough terrain, and even ascend stairs using a novel method.

The breakthrough is the product of almost a decade of work by a team of experts from France and Switzerland.

Last year, the researchers demonstrated that a spinal cord implant, which emits electrical pulses to trigger movement in leg muscles, had enabled three paralyzed patients to walk again.

But they needed to press a button to move their legs each time. Gert-Jan, who also has a spinal implant, said this made it difficult to get into the rhythm of taking a "natural step".

The most recent study combines the spinal implant with a brain-computer interface, which is inserted above the portion of the brain that regulates leg movement. 

According to the researchers, the interface decodes brain records in real time using algorithms based on artificial intelligence methods.

This permits the interface, which was designed by researchers at France's Atomic Energy Commission (CEA), to work out how the patient wants to move their legs at any time.

The data is sent to the spinal cord implant via a portable gadget that fits in a walker or small backpack, allowing patients to move around without the assistance of others.

The two implants build what the researchers call a "digital bridge" to cross the disconnect between the spinal cord and brain that was created during Gert-Jan's accident.

However, the team is now planning an experiment to see if this technique can restore function in the arms and hands.

They also expect that it will be applicable to other issues, such as stroke-induced paralysis.

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