Have you ever, like, properly looked at your hands? (Photo by Ralph Ackerman/Getty Images)
For a glorious period in the mid-2000s, some loophole appeared in the UK drug laws and it became possible to buy magic mushrooms in Camden Market or any number of high-street shops that smelled of joss sticks. You could only sell them fresh, not dried, for some weird regulatory reason, even though it made no discernible difference to how well they worked. Then someone noticed that young people were having fun, so obviously that was stopped.
Psychedelics, like psilocybin (the active ingredient in magic mushrooms) and lysergic acid diethylamide (LSD), are strange drugs. They don’t automatically make you happier, like MDMA, or more confident, like alcohol. Instead they do … something. They make the world seem unfamiliar. You can see this in any depiction of them in popular media: the spaced-out teenager staring at her hand for hours. “Have you ever really, like, looked at your hand, man?” It’s like an artificial dose of deep-and-meaningfulness.
A few days ago, there was some excitement over a study that found that psilocybin was as effective as escitalopram — the joint-best-performing antidepressant — in the treatment of depression. What’s interesting about the way it is theorised to work is, in fact, in the exact way that it makes the spaced-out teenager look at her hand: it removes the familiarity from our surroundings. And that mechanism can tell us something profound about how our brains interact with the world.
First, though, the study. It took 59 patients diagnosed with moderate-to-severe depression, and gave 30 of them two quite large doses of psilocybin three weeks apart, as well as a course of placebo capsules every day for six weeks; it gave the other 29 a normal daily dose of escitalopram, and a tiny dose – so small as to be ineffective – of psilocybin at the same three-week interval as the others. Then they measured the subjects’ mood, using four standard scales of measuring depression; two questionnaires filled out by the patients, and two by their doctors.
The results were intriguing. The researchers preregistered one of the scales as the “primary outcome” of the study, and the other three (among other things, including measures of well-being, suicidality, work and social functioning, and anxiety) as “secondaries”. That’s to avoid “p-hacking” or “hypothesising after results are known” – getting your data and chopping it up until you can make it say whatever you like.
On the primary outcome, psilocybin did not outperform escitalopram. Or, rather, it did, but not by enough to reach “statistical significance”, so, by convention, scientists say that the result could have been a fluke. Still, though: magic mushrooms did at least as well as the best antidepressant in treating depression, which is quite exciting.
And it did reach statistical significance on several of the secondary measures, and it also had a faster onset and fewer and less troubling side-effects. Preregistration is there for a reason, and we should pay more attention to the primary outcome than the secondary, but it’s all interesting and suggests more research is worthwhile.
Some caveats: First, it’s a small study, and study leader Dr Robin Carhart-Harris of Imperial College London pointed out to me, correctly, that by the standards of exploratory Phase II trials it’s a pretty fair size (and we’ve all been spoiled by these N=30,000 Covid vaccine trials). But still, it’s small and should be treated with caution.
Second, RCTs like this are supposed to be “double-blind” – that is, neither the subject nor the doctor know who’s had the real drug and who’s had the control. Obviously it’s hard to properly hide from people whether they’ve had a psychedelic trip or not, but they hoped the way it was administered would put some doubt in people’s minds. Dr Carhart-Harris said that even in clinical trials into “normal” SSRI antidepressants, about 80% of subjects can correctly guess whether they’re in the treatment group or the placebo one, so this isn’t completely unusual.
And third, the people on the trial were not randomly selected from the population but were self-referred, and were probably all people who wanted to try psychedelics. Dr Carhart-Harris agreed that those who didn’t get the “big, mystical experience you get with psilocybin” would likely have been disappointed.
These are good reasons to be a bit cautious. Certainly the study hasn’t “proved” anything. But I think it’s one more decent data point in a growing body of evidence that psychedelics can have a positive effect on depression, and as long as everyone is upfront about the fact that it’s exploratory and should simply point us towards the value of doing more research, then it’s fine. Other scientists broadly seem to say that it’s definitely good new evidence, if not some huge breakthrough.
But the reason I find it really interesting is the theory behind it. The idea is that depression is caused by our mental models of the world going wrong, and that psilocybin relaxes the hold those models have on our sense of reality.
Here’s what I mean by that. We feel like we’re looking out through a clear, unvarnished window onto the world, but (obviously) that’s not how it is. We only see colour and sharpness in a tiny area in the centre of our field of vision; the image on your retina is distorted by the curve of the eyeball and half-hidden by blood vessels; there’s a big missing bit where the nerve cables to the brain leave the eye. It blurs and moves constantly as our eyes, head and body move around. But our brain is constantly using that information to create what feels like a pin-sharp, three-dimensional image of our surroundings, in real time.
It does that by combining the information from your senses with an existing model. If new information doesn’t meet expectations, it is either ignored or used to update the model. So, to use an example from an earlier paper of Carhart-Harris’s, I have a strong prior belief that walls don’t move rhythmically as though they’re breathing. The unfiltered sense data coming in from my senses is noisy and weird and sometimes it might contain information that could be interpreted as “the walls are breathing”. But my top-down model of the world has that strong prior belief – walls don’t breathe! – so the information is ignored as an anomaly.
Of course, if I had some weaker belief, such as “I used the yellow cup when I made coffee,” and then I looked down at my cup and it seemed blue, then the sense data would override my prior belief, updating it (and it would register as a surprise: my attention would be called to it).
You can see your priors at work when you interpret ambiguous illusions, such as the McGurk Effect or this video of a mask. You don’t tend to see inside-out faces, so your brain really struggles to see one: your strong prior belief is that faces come out, not in.
What psychedelics seem to do is reduce the strength of your top-down models, your prior beliefs, about the world. That means that the sense data coming in can update them more easily. Your rock-solid assumption that walls don’t breathe is rendered much weaker, so random noisy fluctuations in the data coming from your eyes override it, and (as often happens with psychedelic experiences) still objects seem to move: walls seem to breathe, patterns on wallpaper seem to crawl. Things that are utterly familiar which your attention would normally ignore altogether – things like your hand – become strange and alien. I assume you’d be much more capable of seeing that the mask was inside-out if you were on mushrooms.
(People may recognise that this is just Bayes’ theorem: you have a prior belief, of some given level of confidence; new information comes in, and you update that level of confidence appropriately. If your prior belief is strong enough, then it will take a lot of new information to shift it.)
I’ve been talking about visual “beliefs” here – walls don’t move, my coffee cup is yellow, my hand is a pretty normal thing which I don’t need to pay too much attention to. But this system of prior beliefs updated with new information applies to much higher-level concepts as well. Imagine I have a prior belief that I am a productive and decent member of society, and then some new information comes in that I am in fact a chiselling little crook: say, I get convicted of fraud. Depending on the confidence of my prior belief and the strength of the new information, I will reduce my confidence in my belief or even change it altogether.
What Carhart-Harris and Karl Friston suggested in their previous paper (see here for a good writeup) was that in depression, our prior beliefs get stuck in a sort of “hole” that is too deep for new information to shift it out of. We form pathological, incorrect beliefs about how terrible everything is or how worthless we are, and the belief is so confident that new information coming in – good news or positive feedback or whatever – is unable to shift it.
They have a metaphor of a sort of belief “landscape”, with hills and valleys. You are a little car or something on the landscape; you naturally roll downhill, but you can go a little way uphill, with work. The further down you are, the “truer” your beliefs are, or – more precisely – the more accurately they match your experiences. So your goal is to get as low as possible. Strong beliefs like “walls don’t breathe” are very deep valleys, and it takes huge amounts of new information to “drive” up the sides of them to get out; weaker beliefs such as “my coffee cup is yellow” are shallower, and just a little bit of information lets you get out and roll down into the deeper, more accurate valley, marked “my coffee cup is blue”.
The trouble is, you might end up getting stuck in a local dip, unable to climb out into the deeper, better valley next door. That’s a delusional state: you have some belief, “the US government is run by paedophiles out of a pizza restaurant”, say. The world would make more sense if you didn’t hold that belief, but the sides of the valley are too steep to get out into the next one, in which the US government isn’t run by paedophiles out of a pizza restaurant. So even though new information comes in, it’s never enough to shift you out, and you keep rolling back down.
This is what is apparently going on with depression, according to Carhart-Harris. Your prior beliefs have formed a “landscape” in which you are stuck in a delusional belief about your own worthlessness or the terribleness of the world. If you could get enough information to get you out of it, you’d roll down into the deeper, more accurate valley next door in which you’re not depressed. But you can’t.
Now, psychedelics. Remember how they weaken your Bayesian priors? In this metaphor, that means they reduce the height of the hills and the depths of the valleys: they flatten the landscape. Suddenly, while on psychedelics, pessimistic or negative beliefs are weakened (along with beliefs in non-breathing walls). So your little car can drive out of the valley and by the time the psychedelics wear off, and the hills and valleys become steep again, you have successfully moved into the non-delusional bit and stay there.
This Bayesian model seems to be the closest thing there is to a working theory of how the brain works; it seems to explain decision-making and willpower quite effectively, among many other things. We have prior beliefs and update them all the time with new information. Our brains are constantly generating a model of the world, and hallucinations happen when our confidence in that model is reduced so we pay more attention to anomalous sensory fluctuations.
Of course, the fact that there’s a convincing-sounding theory behind psychedelic therapy for depression doesn’t mean it’s true; one scientist friend says that “When people repurpose a drug/activity that they enjoy taking/doing, and say it cures depression, I’m highly sceptical. You might even call it my … prior.” So let’s remain cautious.
And, of course, even if it does work, psychedelics relax your priors on true beliefs as well as false ones – so it is possible that you would climb your way out of some real belief and then settle into a delusional one. Carhart-Harris agrees this is a risk, albeit a rare one, and that’s why it’s important to use psychedelic therapy only in carefully controlled situations.
And there’s a further problem that even if it is shown to work, there’s a strong societal and regulatory resistance to the use of recreational drugs as medicines. Professor David Nutt, a professor of neuropsychopharmacology, also at Imperial and who also worked on the study, agreed that that is a difficulty, but he felt that the growing evidence of their effectiveness and the overwhelming evidence of their comparative safety should overcome it. (“I wouldn’t care if they ended up in the same category as morphine,” he said, “as long as they can be used in medicine. But they shouldn’t have been illegal in the first place.”) Other psychoactives, such as ketamine and MDMA, are also being studied for use on depression and PTSD.
I hope psychedelics turn out to be effective against depression, if only because almost nothing else is – antidepressants do “work”, as in have more effect than placebo, but it’s extremely hit-and-miss and any given SSRI will probably have no therapeutic effect in any given patient: doctors will probably have to try several before finding an effective one. But I also hope they’re effective because I think the theory is lovely and elegant, making good clinical use of this theory that our brains are Bayesian reasoning machines, and that sometimes our priors can get too strong and need a bit of massaging to relax them.
And I also hope they start selling them in Camden Market again. I’m too old for that stuff these days, but I don’t get why the young people shouldn’t be allowed to have fun.
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SubscribeVery thoughtful and discouraging essay. Maybe this is how it all ends – not some cataclysmic event, but a slow and malignant growth of red tape, choking off development in all sectors of the economy. Something is seriously wrong if construction jobs have not grown in 20 years. Government jobs have probably tripled in that same time period. Very sad.
I only seem to be able to comment in the form of a reply to somebody else’s comment. I think there’s something wrong with the iPhone app… so apologies for winging in on your coattails. BUT… as far as the construction element of the article goes, it seems to me that houses should really be made in factories under tight quality control; pre-wired and pre-plumbed. Then assembled and connected on site. The current chaotic reality of disparate subcontracting trades, all tacitly at war with eachother; competing on price (ensuring there’s no investment in training), makes no sense in the 21st century. Although I spose you could say that about plenty of other things.
This actually happens quite a bit in Canada. It’s not a huge industry, but there are many factory built homes – in Alberta anyway. Not sure about other provinces or Britain.
It’s an industry they need urgently to invest in. My sister who lives in Vancouver says that there is a huge deficit of houses in Canada and that the prices have shot up horrendously in the last 10 years. As the population has increased, housebuilding has actually fallen. Although Canada still has huge resources in land and materials per head of population, mortgages are becoming unaffordable due to govt spending, quantitative easing and ever-expanding bureaucracy, which has led to inflation currently at about 4.8%. (Justin Trudeau’s spending spree during Covid is coming home too).
So the average house price in Canada is the equivalent of about £520,000, nearly twice that in the UK, where we have much greater challenges with space, population & overseas ‘investment buying’.
Isn’t it good to know we’re not the only nation mismanaging the housing & welfare needs of our citizens…
Canada housing prices are because the Chinese bought in massively – it gives them safe investment and the ability to live there if they invest enough.
This is half of it. The rest is massive immigration. Canada at least has the space. The cities could really do with densification. But the buildings will be ugly and functional, dictated by roads and have zero joie de vivre
Immigration too. We had 450,000 immigrants last year. Building can’t keep up and over regulation doesn’t help either
It’s pretty ugly in some parts of the country. I live an hour outside Edmonton – pretty easy commuting distance. My house value hasn’t went up in a decade and is worth $240,000. It would be worth $1 mill in Vancouver.
Good idea – I am investing in a startup, ”Pods Inc” Small – 8ft X 8ft x 20 foot deep, each a whole house for 1 – 2 (pod). Can be stacked up to 30 high in any amount and configuration, with bolt on walkways and stairs and even elevators by the stairs. Plumbing and wiring just plug into the one below as the fork lift stacks them.
Can come with modular community distribution centers (amazon instant) and healthy ready meal outlet specializing in ‘Land Shrimp’ based, ‘ climate wise, animal meat free,’ meals.
No Parking needed as you can walk anywhere you would need to go in 15 minutes or less.
Sounds Great – affordable housing and save the planet in one product.
Sounds great, but if everything is within a 15 minute walk we’re talking highly dense neighbourhoods. Wouldn’t the land value make these tremendously expensive regardless.
I totally agree that current housebuilding technology is hopelessly inefficient and outdated. It’s a shame that recent companies like Legal and General’s Modular Housing, have wound down or gone bust. The common thread of the failures seems to be underestimating the difficulty of connecting to services, trying to use brick rather than composite panels, and not using automation for module assembly. A complete rethink of the design of a modular house is required. Modular houses should be like products from a FMCG production line – good quality, efficiently made, in demand, and most importantly, good value for money
https://www.constructionnews.co.uk/tech/offsite-mmc/modular-builder-insolvencies-hit-warranty-scheme-08-12-2023
There is a good article on Bloomberg on the UKs failure to allow self building compared to other countries.
https://www.bloomberg.com/opinion/articles/2024-01-03/the-uk-s-communist-new-build-housing-market-is-ripe-for-revolution
This rather sounds like “it’s been a disaster so far so let’s do more of it”!
Surely simple well made and affordable brick buildings – which the UK has a long tradition of – really shouldn’t be that difficult?
I’d be open to living in a modular building but I’d be particularly keen on the assurance of its quality.
I believe that some attempts to adopt this approach in the UK have also been a fiasco!
Realistically its not too many government jobs so much as jobs doing the wrong thing.
If we look at more successful cities (in housing terms) like Vienna, there is heavy government involvement but rather than helping NIMBYs to slow things down, those government officials have instead been able to allow faster construction while continually increasing the quality.
As a result monthly costs in Vienna are much lower than competing cities such as Munich, Zurich etc. even though salaries in Austria are quite high (at least for anyone who can speak German).
Thanks for this
Yes indeed – something is very wrong! We exist – as an EU Legacy Progressive State – in a degrowth anti capitalist economy. ..one openly hostile to wealth creation ..by intent. The risk aversion built into the EU’s sickly Regulatory & Bureaucracltic governance Machine has seen the suffocation strangulation and crippling of market dynamism in Europe and the UK. Long gone is Thatcherite enterprise culture. A broken vast public sector and Quangocratic Blob have squeezed the life out of our labour, energy financial and housing market. ESG. DEI. Net Zero. Furlough. QE. Look at the BBC reaction to the opd idea that wealth creators and strivers should be given tax cuts and incentives. The horror!! The state equalitarian and anti discriminatory ..and its ancillary culture of entitlement and humsn rights – has in 15 short years made enterprise a dirty word. This is the trap we are in.
A bit of a rant here. I support Brexit but suspicious that is the EU is that found of all evil narrative. Austria is also an EU state (!) and a current one at that.
A much under discussed factor of Britain’s membership of the EU, is how we would relentlessly gold plate every regulation that came out of Brussels, this making the application more complex and prescriptive and costly. This was entirely a matter for the British authorities
I’m still not sure why this author is claiming that Nimbyism is “a very British form of populism”.
Why mention populism at all ? What relevasnce does it have here ?
Otherwise a good article.
Somehow omits to mention the 1947 Town and Country Planning Acts and the Green Belt. Both things which seem – like the NHS – to go unquestioned (also products of Attlee’s government). Interestingly, the original 1947 Act did capture some development planning gain (abolished in 1955) – something I think that should be considered again. As should relaxation of the Green Belt.
It is incorrect to assume that all homeowners oppose new housing developments and see higher house prices as being a good thing.
Interesting also that more young people are becoming interest in apprenticeships. Plumbers, electricians and builders will still be needed even if AI wipes out some of the less skilled graduate jobs.
NIMBYism it not unique to Britain and I say that as an American where people regularly fight against anything that threatens to tread on their lifestyles. These battles range from opposing windmills that would spoil million dollar views to multi-family construction near single-family neighborhoods to large-scale business operations within a 30-mile radius of residential area.
Why this remarkable sensitivity to the term “populism”? I don’t even know why this is supposed to be a negative term.
I do however think is the case is that some anti-establishment politicians come up with very simplistic solutions which don’t analyze the problem correctly, nor have a well thought through political program, and have been complete failures in office as a result. Others of backtracked from simplistic commitments, to example to leave EU or abandon the Euro when they belatedly come to realise these measures would have very bad short-consequences at least in the short term. This is where the term “populism” perhaps (rightly!) acquires some of its negative connotation.
Preventing development could in these terms certainly be seen as a populist movement – it’s certainly a popular one in many areas of Britain.
I definitely agree that housing construction has been slowed to an unacceptable level by politicians giving too much weight to Nimby complaints.
We need more medium density housing in all our cities.
Shorter: The bossy Left runs England and it’s beginning to reach crisis level disarray as a result.
I’m curious about the workmen on the building crews. How many are from former SSRs? How many from Africa? India? What are the skills they must prove they possess during the hiring process? Do they need to produce some sort of certification? It would seem that those charged with building homes and flats wouldn’t want them to collapse and kill residents (that Camden development is almost unbelievable).
Good God, hair stylists in the US are required to be licensed and certified, for crying’ out loud.
Workers on construction projects in the UK are required to be qualified.
https://www.cscs.uk.com/card-type/labourer/
The supposed party of home ownership, individual opportunity and economic growth cannot supply the one basic commodity that would most facilitate all these goals, even as it has created still more demand by overseeing historically unprecedented levels of immigration.
I must have missed in all this where they, the Tories, are responsible for home building. It’s not Labor’s job, either, any more than it is the role of political parties to provide cars, televisions, cell phones, or grocery stores. What both CAN do and should do is address the “unprecedented levels of (illegal) immigration” that are not just straining the system, but also drowning the native culture.
There have been housing targets set by all UK governments since the second world war.
So n that sense the governments ARE responsible for ensuring sufficient houses are built. This doesn’t mean to say they have to build themselves of course. Whether this approach is merited or not it is a reality. And the failure of successive governments to meet their own targets is very revealing.
So often people love to talk about immigration and I agree that imposes additional strains and demands on housing. However it doesn’t mean to say that it cannot be met and vastly higher numbers of houses were built in the immediate period after the Second World War for example.
No mention of immigration in this article making it essentially worthless as it only focuses on the supply of housing, not the demand on housing.
The article does in fact specifically mention immigration, more than once!
“The supposed party of home ownership, individual opportunity and economic growth cannot supply the one basic commodity that would most facilitate all these goals, even as it has created still more demand by overseeing historically unprecedented levels of immigration”
However immigration is not the only issue here, nor would it be impossible to have an infrastructure plan to meet the immigration demands, at least in terms of physical infrastructure.
That we are not doing so is a failure of the state without doubt, but is not impossible to build at a much faster rate housing and other infrastructure than we are now managing.
As a Londoner living in high density development area I seen thousands of new flats being built within a 15 min walk radius from my house in the past 5 to 8 years. Same applies to many other parts of London which have been completely transformed by dense, high rise buildings in the past decade in a half.
I therefore find it difficult to understand the constant rants about lack of housing development. The issue isn’t with lack of houses being built. It is with them being built in areas there only young people, minorities/ migrants and the rich want to live.
The other issue, which the article completely ignored is the thousands of properties bought in British cities by foreign investors which remain empty most or all of the year. Huge swathes of central London are now ghost towns because consecutive London mayors didn’t want to deal with this problem, as it enriched their cronies.
Exactly. There is a vast amount of house-building going on in my home city of Brighton – but it is all flats for students to rent ! No sign of houses for families. (and I wonder about all the vast blocks of flats I see from the train from Clapham Junction into Victoria Station – who is living there aside from a few people to seem to be drying their washing ??)
I commented above re. my experience in London. Also my daughter in Manchester. I hadn’t seen your comment then!
Here in Brooklyn they’ve been building like mad for years. Towers sprout like weeds. And the prices just go up and up; for renters and buyers, far faster than the population. But for some odd reason people “in the know” keep quoting Adam Smith, anyway.
Mr. Smith wrote about “supply and demand” around 250 years ago. He was theorizing about a “capitalism” that was nothing like it is today. Capital holders have used those years, and their generous resources, to “game the system”. Mostly through tax breaks.
Being a developer today means, basically, “heads I win, tails you (the taxpayer) lose.” Knocking down a row of lovely old homes and replacing them with a visual insult in the form of a concrete tower will put millions of dollars in his pocket. Even if the New Luxury Penatentiery-style Blight remains empty.
I often see towers on a chilly winter night, 9 or 10:00 PM, with just one or two of a hundred apartments lit. And yet another tower just starting to rise right next door.
Please find another line of reasoning. “Supply and demand” is just silly.
Supply and demand of credit is the major reason, and explains why prices have gone up everywhere (we’veall had loose credit for the last couple of decades), regardless of amount of building and land available. But physical supply and demand is an issue as well.
Very interesting. Thanks.
Why did it take the writer 10 inches, vertically, to finally write ‘to put it bluntly’?
The so-called NIMBYs have been lied to, consistently over such a long period of time, you cannot blame them for being sceptical every time a new planning application arrives.
Affordable homes, community benefits all these lovely sweeteners which are promised never materialise. Never.
Within a few miles of my home we have:-
A site for which planning permission was granted to build 10 houses is up for sale. Permission was granted for this over 10 years ago, nothing has been built.
A development of 30 houses, including 15 affordable homes, is mired in controversy. Once permission was granted the developer immediately applied to reduce the number to 10. Now he wants this to be reduced to none. This is not one of the big 6, it’s a small local developer.
A nearby town accepted the need for a huge increase in house building predicated on the building of a new railway station and the reopening of a section of disused track. This is because the roads between it and the nearby city (where most people work) are already at capacity. It is now obvious that this new rail link will never – can never – be built.
There are many more examples like this I could go on at some length.
The main reason people build houses in this country is to make money for investors and shareholders. Until the main focus is on providing homes people need, with profit coming as second to that, we will never solve the problem of the shortage of homes.
I live in a London suburb where high rise blocks of flats are being built and existing blocks having storeys added while the need for family homes is being ignored.
Where my daughter lives in the North of England, many family homes are being built but no schools. Construction companies are required to build a school for every 1,000 homes but build 999 homes and then move on elsewhere.
There is a shortage of social housing nation wide since Margaret Thatcher sold off council houses without building more. I understand that many of those are now rented out by private landlords.