It would be easy to consider Robert Bryden's goals modest.
One day he'd like to work as a builder. He'd like to be able to drive, so he can take people to their weddings in a classic car, which he will have restored with the help of his Dad, Robert Snr.
It's tempting to say the 29-year-old wants his old life back. But Robert doesn't recall his old life. He has no real idea who or what he was prior to an attack outside a Wellington pub that left him with a traumatic brain injury known as a diffuse axonal; and only a blurred grasp on much of what has happened since.
Robert was repeatedly kicked in the head during a vicious attack. His assailant, Ioritana Tuau, who witnesses said held onto a railing to get better leverage as he stomped on Robert, received a nine-year jail sentence.
Robert got life - or rather a lifetime of rehabilitation. When he emerged from a month-long coma, he was blind, had little control of his body and was so severely mentally impaired he would forget his parents' names in a matter of seconds.
He was, as Robert Snr puts it, "munted".
His goals, then, are far from modest.
It's a week short of the 4th anniversary of the night that changed his life - and the lives of many around him - when Robert tells the Herald of his dreams. He's lucid, cheerful and has no problem engaging in conversation.
His reference to restoring cars is no surprise. He's been stripping down engines as part of his rehabilitation. The idea was to help improve his hand-eye coordination, says Robert Snr, a mechanic and builder who has given up work to concentrate on his son's rehabilitation. His methods are unconventional. He's made Robert walk sand dunes to re-train his muscle memory, developed a gym-based cognitive training exercise using coloured cones and generally eschewed mainstream medicine.
The biggest breakthrough came this year, when Robert Snr agreed to let Hayley Brown treat his son with hyperbaric oxygen at her Paraparaumu clinic.
Robert has just completed a second block of 40 90-minute sessions in a pressurized cylinder breathing elevated levels of oxygen. The results have been encouraging.
The most startling effect has been on his peripheral vision. Dots on a series of graphs Robert Snr holds illustrate how much his son's vision has improved. But to what extent can they be attributed to HBOT, as hyperbaric oxygen therapy is known?
"I can only go by the testing we have had done after we've had hyperbaric, with the behavioral optometrist, and seen the growth," says Robert Snr.
"I would not have expected it to grow that quickly, and he has never plateaud. He is still climbing."
Brown has no doubts her treatment is driving Robert's improvement. Her Health Evolution clinic has treated five other traumatic brain injury (TBI) victims with HBOT and they are all cured, she says.
Brown passionately believes HBOT can be used to treat head injuries ranging from rugby concussions brain damaged car crash victims, and possibly even strokes.
Given the lack of alternative treatments, she's appalled HBOT isn't more widely used within mainstream medicine - and wants to know why.
The answer, says associate professor Simon Mitchell, the head of Auckland University's anaesthesiology department and New Zealand's leading expert in hyperbaric medicine, is science.
"It's just fanciful bollocks," says Mitchell of the notion that brain injuries can be treated with HBOT.
"I'm very disturbed about it."
The proliferation of such nonsense, he says, is bad for the field and exploitative of patients, most of whom are extremely vulnerable.
Hyperbaric medicine has long battled for credibility. Couched in a hard to contradict philosophy that oxygen is central to life, it has been a lightening rod for practitioners of alternate medicine for decades.
Some claim it can heal just about anything. In 2013 America's Food and Drug Agency issued this warning about unsubstantiated claims for HBOT. This list of conditions the FDA warned people HBOT had not been proven to treat included cancer, autism, diabetes and brain injuries.
"Patients may incorrectly believe that these devices have been proven safe and effective for uses not cleared by FDA, which may cause them to delay or forgo proven medical therapies," the FDA warned.
In New Zealand, an advertisement that appeared in the Bay News in 1998 listed 100 ailments that could be treated with hyperbaric oxygen. Many of the conditions were misspelled, as was the word 'hyberbaric'.
The sales pitch is typically thus: the human body requires oxygen to heal, and increasing the oxygen supply boosts the ability and rate of healing. By combining an elevated level of oxygen with increased atmospheric pressure, a hyperbaric chamber forces oxygen into damaged tissues.
The mechanism by which it works is seldom that simple, but it does work - for some ailments. The FDA lists 14 'indications' for which hyperbaric therapy is considered proven, including decompression sickness, burns, radiation injuries, carbon monoxide poisoning and gas gangrene.
TBI is conspicuous by its absence. The reason, says Mitchell, it that is has been proven categorically not to be effective.
Under pressure to follow up on an encouraging independent 2003 experiment, the U.S. military spent $US70 million on a trio of advanced studies. The hope was HBOT could cure the vast numbers of combat troops returning from Iraq and Afghanistan with battered brains.
HBOT treatment - which involved subjects breathing 100 per cent oxygen at pressures ranging from 1.2 atmospheres (ata) to 2.0 ata - produced significant, measurable effects, researchers found. People got better.
But the studies all included what is known as a randomized, double-blinded sham control. Subjects in the sham treatment group were fooled into thinking they were receiving hyperbaric treatment with a combination of plain old room air (roughly 21 per cent oxygen) and mildly elevated pressure (1.3 ata).
The results were virtually identical. People who thought they were receiving HBOT improved at exactly the same rate as those who were genuinely receiving it.
A placebo was well and truly in effect, scientists running all three studies concluded.
"If you had to write a script for the perfect environment for a placebo effect you would write a description of a hyperbaric facility," says Mitchell.
"If you take people who are highly motivated to recover and put them in a caring, sharing, positive, optimistic environment that involves a complicated looking intervention that would almost to the man on the street be inconceivable not to work, then they will change.
"But the inescapable fact is that when you put a sham treatment against an active treatment there is no difference between the two."
The debate, though, does not end there. Proponents of HBOT as a revolutionary cure for TBI reject the placebo theory. The likes of New Orleans-based physician Dr Paul Harch - who in 2001 established the International Hyperbaric Medical Association and made himself president - argue that HBOT is so potent that even room air at a mildly elevated pressure is an active treatment. The sham was no sham at all, Harch and his followers argued.
Utter nonsense, say mainstream hyperbaric practitioners.
"The same pressure of inspired oxygen is achieved just by sitting there in your office breathing bottled oxygen through a plastic mask," says Mitchell, who with Australia colleague Michael Bennett last year published this paper on unsubstantiated claims made for HBOT.
"Then they say 'oh yes but it is the pressure'. Good luck with that argument.
"There is no plausible reason in the world to suspect that exposing yourself to point-three of an atmosphere of pressure is going to resurrect inactive neurons in the brain. That's just fanciful. But that is the line they are taking because the industry that they are creating depends on it."
Robert Bryden Snr isn't impressed with the scientific smackdown of HBOT.
"Everything I understand comes from my gut," he says. "It's inside me."
His gut told him a rehabilitation centre in Porirua wasn't the place for his boy to recover. His gut told him to sack doctors who weren't prepared, as he is, to kick over every stone in search of ways to help Robert Jr.
"I said I want something that is a bit more alternative, you people stick to your book. If you didn't stick to your book then you wouldn't have a job in your hospital because the hospital wouldn't allow you to step outside those boundaries. The hospital basically controls you, which is the government, which is the drug companies."
The 'government in bed with the pharmaceutical companies' conspiracy theory doesn't surprise Mitchell.
"That's just a hoary old chestnut.
"There are plenty of people in [hyperbaric medicine] who would love nothing more than for there to be more indications because that is how they make their living.
"They deny this one because the science doesn't support it."
But not working isn't the same as not having an effect. Robert's recovery is there for all to see.
"It becomes a very complicated argument because the effects they are seeing are real," says Mitchell.
"That's the problem. That is why people like [Brown] are true believers. They see people change, they see people 'recover'.
"But let's be clear - no one is getting cured or having some kind of miraculous change. No one has come in as vegetable and walked out a normal person. That doesn't happen."
Brown disagrees. A placebo effect could not have caused Robert's improvement because he lacked the cognitive function to manifest one," she says.
"He had no understanding that he'd had an injury. He couldn't have imagined it because he didn't have an imagination."
Robert Snr doesn't much care if it is a placebo that is helping his son. If placebos work, then why not use them, he asks?
"Ask yourself what a patient might think if they committed significant time and money to a treatment that did not work for them, and they subsequently found out that they were being deceived about its true efficacy?" answers Mitchell.
"The provider would essentially have to say 'yes we lied to you in the hope that the lie itself would cause you to believe that it worked - but thanks for your money anyway'. Hmmmm."
Money is often at the crux of the issue, says Mitchell. Treatments are expensive, ranging from $100 to $200 a session. Clinics run by the likes of Harch are large scale and highly commercial. A proliferation of head injuries, a lack of effective treatments and the powerful placebo effect means true believers are in good supply.
Brown, who discovered HBOT while seeking treatment for an illness of her own, insists she is not in it for the money.
"I say give us some cases and we'll show you [it works]," she says. "I'd happily treat them for nothing to prove what it will do.
"The people coming in here are tragic cases. They have got no hope. There is nothing else. You give them treatment and they improve quite markedly quite quickly. Someone needs to give us the opportunity to show what it can do."
Mitchell disagrees vehemently. Once desperate patients are sucked in to a treatment cycle, extracting them is nearly impossible, he says.
"They will be seeing changes which are real and trying to talk them out of it will be impossible. You can't expect someone in a desperate situation like that to change their view. That's what makes it so exploitative.
"It's deception. With all the good intent in the world, it is still deception."