Depressed Or Bereaved? (Part 1)

Part 2 is now out here.

My cat died on Tuesday. She may have been a manipulative psychopath, but she was a likeable one. She was 18.On that note, here's a paper about bereavement.

It's been recognized since forever that clinical depression is similar, in many ways, to the experience of grief. Freud wrote about it in 1917, and it was an ancient idea even then. So psychiatrists have long thought that symptoms, which would indicate depression in someone who wasn't bereaved, can be quite normal and healthy as a response to the loss of a loved one. You can't go around diagnosing depression purely on the basis of the symptoms, out of context.

On the other hand, sometimes grief does become pathological - it triggers depression. So equally, you can't just decide to never diagnose depression in the bereaved. How do you tell the difference between "normal" and "complicated" grief, though? This is where opinions differ.

Jerome Wakefield (of Loss of Sadness fame) and colleagues compared two methods. They looked at the NCS survey of the American population, and took everyone who'd suffered a possible depressive episode following bereavement. There were 156 of these.

They then divided these cases into "complicated" grief (depression) vs "uncomplicated" grief, first using the older DSM-III-R criteria, and then with the current DSM-IV ones. Both have a bereavement exclusion for the depression criteria - don't diagnose depression if it's bereavement - but they also have criteria for complicated grief which is depression, exclusions to the exclusion.

The systems differ in two major ways: the older criteria were ambiguous but at the time, they were generally interpreted to mean that you needed to have two features out of a possible five; prolonged duration was one of the list and anything over 12 months was considered "prolonged". In DSM-IV, however, you only need one criterion, and anything over 2 months is prolonged.

What happened? DSM-IV classified many more cases as complicated than the older criteria - 80% vs 45%. That's no surprise there because the criteria are obviously a lot broader. But which was better? In order to evaluate them, they compared the "complicated" vs "normal" episodes on six hallmarks of clinical depression - melancholic features, seeking medical treatment, etc.

They found that "complicated" cases were more severe under both criteria but the difference was much more clear cut using DSM-III-R.

Wakefield et al are not saying that the DSM-III-R criteria were perfect. However, it was better at identifying the severe cases than the DSM-IV, which is worrying because DSM-IV was meant to be an improvement on the old system.

Hang on though. DSM-V is coming soon. Are they planning to put things back to how they were, or invent an even better system? No. They're planning to, er, get rid of the bereavement criteria altogether and treat bereavement just like non-bereavement. Seriously. In other words they are planning to diagnose depression purely on the basis of the symptoms, out of context.

Which is so crazy that Wakefield has written another paper all about it (he's been busy recently), which I'm going to cover in an upcoming post. So stay tuned.

Wakefield JC, Schmitz MF, & Baer JC (2011). Did narrowing the major depression bereavement exclusion from DSM-III-R to DSM-IV increase validity? The Journal of nervous and mental disease, 199 (2), 66-73 PMID: 21278534

Depressed Or Bereaved? (Part 1)

Part 2 is now out here.

My cat died on Tuesday. She may have been a manipulative psychopath, but she was a likeable one. She was 18.On that note, here's a paper about bereavement.

It's been recognized since forever that clinical depression is similar, in many ways, to the experience of grief. Freud wrote about it in 1917, and it was an ancient idea even then. So psychiatrists have long thought that symptoms, which would indicate depression in someone who wasn't bereaved, can be quite normal and healthy as a response to the loss of a loved one. You can't go around diagnosing depression purely on the basis of the symptoms, out of context.

On the other hand, sometimes grief does become pathological - it triggers depression. So equally, you can't just decide to never diagnose depression in the bereaved. How do you tell the difference between "normal" and "complicated" grief, though? This is where opinions differ.

Jerome Wakefield (of Loss of Sadness fame) and colleagues compared two methods. They looked at the NCS survey of the American population, and took everyone who'd suffered a possible depressive episode following bereavement. There were 156 of these.

They then divided these cases into "complicated" grief (depression) vs "uncomplicated" grief, first using the older DSM-III-R criteria, and then with the current DSM-IV ones. Both have a bereavement exclusion for the depression criteria - don't diagnose depression if it's bereavement - but they also have criteria for complicated grief which is depression, exclusions to the exclusion.

The systems differ in two major ways: the older criteria were ambiguous but at the time, they were generally interpreted to mean that you needed to have two features out of a possible five; prolonged duration was one of the list and anything over 12 months was considered "prolonged". In DSM-IV, however, you only need one criterion, and anything over 2 months is prolonged.

What happened? DSM-IV classified many more cases as complicated than the older criteria - 80% vs 45%. That's no surprise there because the criteria are obviously a lot broader. But which was better? In order to evaluate them, they compared the "complicated" vs "normal" episodes on six hallmarks of clinical depression - melancholic features, seeking medical treatment, etc.

They found that "complicated" cases were more severe under both criteria but the difference was much more clear cut using DSM-III-R.

Wakefield et al are not saying that the DSM-III-R criteria were perfect. However, it was better at identifying the severe cases than the DSM-IV, which is worrying because DSM-IV was meant to be an improvement on the old system.

Hang on though. DSM-V is coming soon. Are they planning to put things back to how they were, or invent an even better system? No. They're planning to, er, get rid of the bereavement criteria altogether and treat bereavement just like non-bereavement. Seriously. In other words they are planning to diagnose depression purely on the basis of the symptoms, out of context.

Which is so crazy that Wakefield has written another paper all about it (he's been busy recently), which I'm going to cover in an upcoming post. So stay tuned.

Wakefield JC, Schmitz MF, & Baer JC (2011). Did narrowing the major depression bereavement exclusion from DSM-III-R to DSM-IV increase validity? The Journal of nervous and mental disease, 199 (2), 66-73 PMID: 21278534

Psychoanalysis: So Bad It's Good?

Many of the best things in life are terrible.


We all know about the fun to be found in failure, as exemplified by Judge A Book By Its Cover and of course FailBlog. The whole genre of B-movie appreciation is based on the maxim of: so bad, it's good.

But could the same thing apply to psychotherapies?

Here's the argument. Freudian psychoanalysis is a bit silly. Freud had pretensions to scientific respectability, but never really achieved it, and with good reason. You can believe Freud, and if you do, it kind of make sense. But to anyone else, it's a bit weird. If psychoanalysis were a person, it would be the Pope.

By contrast, cognitive-behavioural therapy is eminently reasonable. It relies on straightforward empirical observations of the patient's symptoms, and on trying to change people's beliefs by rational arguments and real-life examples ("behavioural experiments"). CBT practitioners are always keen to do randomized controlled trials to provide hard evidence for their success. CBT is Richard Dawkins.

But what if the very irrationality of psychoanalysis is its strength? Mental illness is irrational. So's life, right? So maybe you need an irrational kind of therapy to deal with it.

This is almost the argument advanced by Robert Rowland Smith in a short piece In Defence of Psychoanalysis:

...The irony is that in becoming more “scientific”, CBT becomes less therapeutic. Now, Freud himself liked to be thought of as a scientist (he began his career in neurology, working on the spinal ganglia), but it’s the non-scientific features that make psychoanalysis the more, not the less, powerful.

I’m referring to the therapeutic relationship itself. Although like psychoanalysis largely a talking cure, CBT prefers to set aside the emotions in play between doctor and patient. Psychoanalysis does the reverse. To the annoyance no doubt of many a psychoanalytic patient, the very interaction between the two becomes the subject-matter of the therapy.

The respected therapist and writer Irvin Yalom, among others, argues that depression and associated forms of sadness stem from an inability to make good contact with others. Relationships are fundamental to happiness. And so a science that has the courage to include the doctor’s relationship with the patient within the treatment itself, and to work with it, is a science already modelling the solution it prescribes. What psychoanalysis loses in scientific stature, it gains in humanity.

Rowland Smith's argument is that psychoanalysis offers a genuine therapeutic relationship complete with transference and countertransference, while CBT doesn't. He also suggests that analysis is able to offer this relationship precisely because it's unscientific.

Human relationships aren't built on rational, scientific foundations. They can be based on lots of stuff, but reason and evidence ain't high on the list. Someone who agrees with you on everything, or helps you to discover things, is a colleague, but not yet a friend unless you also get along with them personally. Working too closely together on some technical problem can indeed prevent friendships forming, because you never have time to get to know each other personally.

Maybe CBT is just too sensible: too good at making therapists and patients into colleagues in the therapeutic process. It provides the therapist with a powerful tool for understanding and treating the patient's symptoms, at least on a surface level, and involving the patient in that process. But could this very rationality make a truly human relationship impossible?

I'm not convinced. For one thing, there can be no guarantee that psychoanalysis does generate a genuine relationship in any particular case. But you might say that you can never guarantee that, so that's a general problem with all such therapy.

More seriously, psychoanalysis still tries to be scientific, or at least technical, in that it makes use of a specialist vocabulary and ideas ultimately derived from Sigmund Freud. Few psychoanalysts today agree with Freud on everything, but, by definition, they agree with him on some things. That's why they're called "psychoanalysts".

But if psychoanalysis works because of the therapeutic relationship, despite, or even because, Freud was wrong about most things... why not just chat about the patient's problems with the minimum of theoretical baggage? Broadly speaking, counselling is just that. Rowland Smith makes an interesting point, but it's far from clear that it's an argument for psychoanalysis per se.

Note: A truncated version of this post briefly appeared earlier because I was a wrong-button-clicking klutz this morning. Please ignore that if you saw it.

Psychoanalysis: So Bad It's Good?

Many of the best things in life are terrible.


We all know about the fun to be found in failure, as exemplified by Judge A Book By Its Cover and of course FailBlog. The whole genre of B-movie appreciation is based on the maxim of: so bad, it's good.

But could the same thing apply to psychotherapies?

Here's the argument. Freudian psychoanalysis is a bit silly. Freud had pretensions to scientific respectability, but never really achieved it, and with good reason. You can believe Freud, and if you do, it kind of make sense. But to anyone else, it's a bit weird. If psychoanalysis were a person, it would be the Pope.

By contrast, cognitive-behavioural therapy is eminently reasonable. It relies on straightforward empirical observations of the patient's symptoms, and on trying to change people's beliefs by rational arguments and real-life examples ("behavioural experiments"). CBT practitioners are always keen to do randomized controlled trials to provide hard evidence for their success. CBT is Richard Dawkins.

But what if the very irrationality of psychoanalysis is its strength? Mental illness is irrational. So's life, right? So maybe you need an irrational kind of therapy to deal with it.

This is almost the argument advanced by Robert Rowland Smith in a short piece In Defence of Psychoanalysis:

...The irony is that in becoming more “scientific”, CBT becomes less therapeutic. Now, Freud himself liked to be thought of as a scientist (he began his career in neurology, working on the spinal ganglia), but it’s the non-scientific features that make psychoanalysis the more, not the less, powerful.

I’m referring to the therapeutic relationship itself. Although like psychoanalysis largely a talking cure, CBT prefers to set aside the emotions in play between doctor and patient. Psychoanalysis does the reverse. To the annoyance no doubt of many a psychoanalytic patient, the very interaction between the two becomes the subject-matter of the therapy.

The respected therapist and writer Irvin Yalom, among others, argues that depression and associated forms of sadness stem from an inability to make good contact with others. Relationships are fundamental to happiness. And so a science that has the courage to include the doctor’s relationship with the patient within the treatment itself, and to work with it, is a science already modelling the solution it prescribes. What psychoanalysis loses in scientific stature, it gains in humanity.

Rowland Smith's argument is that psychoanalysis offers a genuine therapeutic relationship complete with transference and countertransference, while CBT doesn't. He also suggests that analysis is able to offer this relationship precisely because it's unscientific.

Human relationships aren't built on rational, scientific foundations. They can be based on lots of stuff, but reason and evidence ain't high on the list. Someone who agrees with you on everything, or helps you to discover things, is a colleague, but not yet a friend unless you also get along with them personally. Working too closely together on some technical problem can indeed prevent friendships forming, because you never have time to get to know each other personally.

Maybe CBT is just too sensible: too good at making therapists and patients into colleagues in the therapeutic process. It provides the therapist with a powerful tool for understanding and treating the patient's symptoms, at least on a surface level, and involving the patient in that process. But could this very rationality make a truly human relationship impossible?

I'm not convinced. For one thing, there can be no guarantee that psychoanalysis does generate a genuine relationship in any particular case. But you might say that you can never guarantee that, so that's a general problem with all such therapy.

More seriously, psychoanalysis still tries to be scientific, or at least technical, in that it makes use of a specialist vocabulary and ideas ultimately derived from Sigmund Freud. Few psychoanalysts today agree with Freud on everything, but, by definition, they agree with him on some things. That's why they're called "psychoanalysts".

But if psychoanalysis works because of the therapeutic relationship, despite, or even because, Freud was wrong about most things... why not just chat about the patient's problems with the minimum of theoretical baggage? Broadly speaking, counselling is just that. Rowland Smith makes an interesting point, but it's far from clear that it's an argument for psychoanalysis per se.

Note: A truncated version of this post briefly appeared earlier because I was a wrong-button-clicking klutz this morning. Please ignore that if you saw it.

Shock and Cure - With Magnets

Electroconvulsive therapy (ECT) is the oldest treatment in psychiatry that's still in use today. ECT uses a brief electrical current to induce a generalized seizure. No-one knows why, but in many cases this rapidly alleviates depression - amongst other things.

The problem with ECT is that it may cause memory loss. It's hotly debated how serious of a problem this is, and most psychiatrists agree that the risk is justified if the alternative is untreatable illness, but it's fair to say that whether or not it's not as bad as some people believe, the fear that it might be, is the main limitation to the use of the treatment.

Wouldn't it be handy if there was a way of getting the benefits of ECT without the risk of side effects? To that end, people have tried tinkering with the specifics of the electrical stimulation - the frequency and waveform of the current, the location of the electrodes, etc. - but unfortunately it seems like the settings that work best, tend to be the ones with the most side effects.

Enter magnetic seizure therapy (MST). As the name suggests, this is like ECT, except it uses powerful magnets, instead of electrical current, to cause the seizures. In fact though, the magnets work by creating electrical currents in the brain by electromagnetic induction, so it's not entirely different.

MST is thought to be more selective than ECT, in that it induces seizures in the surface of the brain - the cerebral cortex - but not the hippocampus, and other structures buried deeper in the brain, which are involved in memory.

It was first proposed in 2001, and since then it's been tested in a number of very small trials in monkeys and people. Now a group of German psychiatrists say that it's as effective as ECT, but with fewer side effects, in a new trial of 20 severely depressed people. Ironically, they work on Sigmund Freud Street, Bonn. I am not sure what Freud would say about this.

The trial was randomized, but not blinded: it's hard to blind people to this because the equipment used looks completely different. Nor was there a placebo group. All the patients had failed to improve with multiple antidepressants, and psychotherapy in almost all cases, and were therefore eligible for ECT. If anything, the MST group were slightly more ill than the ECT group at baseline.

The ECT they used was right unilateral. This is probably not quite as effective as stimulation which targets both sides of the brain (bitemporal or bifrontal), but has fewer side-effects.

So what happened? After 12 sessions, MST and ECT both seemed to work, and they were equally effective on average. Some patients got much better, some only got a bit better.

What about side effects? MST was noticeably "gentler", in that it didn't cause headaches or muscle pain, and people recovered from the seizures much faster (2 minutes vs 8 minutes to reorientation) after MST. This may have been because the seizures (as assessed using EEG) were less intense.

In terms of the all-important memory and cognitive side effects, however, it's not clear what was going on. They used a whole bunch of neuropsychological tests. In some of them, people got worse over the course of the sessions. In others, they got better. But in several, the scores went up and down with no meaningful pattern. If anything the MST group seemed to do a bit better but to be honest it's impossible to tell because there's so much data and it's so messy.

Unfortunately the tests they used have been criticized for not picking up the kinds of memory problems that some ECT patients complain of e.g. the "wiping" of old memories. For some reason they didn't just ask people whether they felt their memory was damaged or not.

Overall, this trial confirms that MST is a promising idea, but it remains to be seen whether it has any meaningful advantages over old school shock therapy...

Kayser S, Bewernick BH, Grubert C, Hadrysiewicz BL, Axmacher N, & Schlaepfer TE (2010). Antidepressant effects, of magnetic seizure therapy and electroconvulsive therapy, in treatment-resistant depression. Journal of psychiatric research PMID: 20951997

Shock and Cure - With Magnets

Electroconvulsive therapy (ECT) is the oldest treatment in psychiatry that's still in use today. ECT uses a brief electrical current to induce a generalized seizure. No-one knows why, but in many cases this rapidly alleviates depression - amongst other things.

The problem with ECT is that it may cause memory loss. It's hotly debated how serious of a problem this is, and most psychiatrists agree that the risk is justified if the alternative is untreatable illness, but it's fair to say that whether or not it's not as bad as some people believe, the fear that it might be, is the main limitation to the use of the treatment.

Wouldn't it be handy if there was a way of getting the benefits of ECT without the risk of side effects? To that end, people have tried tinkering with the specifics of the electrical stimulation - the frequency and waveform of the current, the location of the electrodes, etc. - but unfortunately it seems like the settings that work best, tend to be the ones with the most side effects.

Enter magnetic seizure therapy (MST). As the name suggests, this is like ECT, except it uses powerful magnets, instead of electrical current, to cause the seizures. In fact though, the magnets work by creating electrical currents in the brain by electromagnetic induction, so it's not entirely different.

MST is thought to be more selective than ECT, in that it induces seizures in the surface of the brain - the cerebral cortex - but not the hippocampus, and other structures buried deeper in the brain, which are involved in memory.

It was first proposed in 2001, and since then it's been tested in a number of very small trials in monkeys and people. Now a group of German psychiatrists say that it's as effective as ECT, but with fewer side effects, in a new trial of 20 severely depressed people. Ironically, they work on Sigmund Freud Street, Bonn. I am not sure what Freud would say about this.

The trial was randomized, but not blinded: it's hard to blind people to this because the equipment used looks completely different. Nor was there a placebo group. All the patients had failed to improve with multiple antidepressants, and psychotherapy in almost all cases, and were therefore eligible for ECT. If anything, the MST group were slightly more ill than the ECT group at baseline.

The ECT they used was right unilateral. This is probably not quite as effective as stimulation which targets both sides of the brain (bitemporal or bifrontal), but has fewer side-effects.

So what happened? After 12 sessions, MST and ECT both seemed to work, and they were equally effective on average. Some patients got much better, some only got a bit better.

What about side effects? MST was noticeably "gentler", in that it didn't cause headaches or muscle pain, and people recovered from the seizures much faster (2 minutes vs 8 minutes to reorientation) after MST. This may have been because the seizures (as assessed using EEG) were less intense.

In terms of the all-important memory and cognitive side effects, however, it's not clear what was going on. They used a whole bunch of neuropsychological tests. In some of them, people got worse over the course of the sessions. In others, they got better. But in several, the scores went up and down with no meaningful pattern. If anything the MST group seemed to do a bit better but to be honest it's impossible to tell because there's so much data and it's so messy.

Unfortunately the tests they used have been criticized for not picking up the kinds of memory problems that some ECT patients complain of e.g. the "wiping" of old memories. For some reason they didn't just ask people whether they felt their memory was damaged or not.

Overall, this trial confirms that MST is a promising idea, but it remains to be seen whether it has any meaningful advantages over old school shock therapy...

Kayser S, Bewernick BH, Grubert C, Hadrysiewicz BL, Axmacher N, & Schlaepfer TE (2010). Antidepressant effects, of magnetic seizure therapy and electroconvulsive therapy, in treatment-resistant depression. Journal of psychiatric research PMID: 20951997

In Dreams

Freud's The Interpretation of Dreams is a very long book but the essential theory is very simple: dreams are thoughts. While dreaming, we are thinking about stuff, in exactly the same way as we do when awake. The difference is that the original thoughts rarely appear as such, they are transformed into weird images.

Only emotions survived unaltered. A thought about how you're angry at your boss for not giving you a raise might become a dream where you're a cop angrily chasing a bank robber, but not into one where you're a bank robber happily counting his loot. By interpreting the meaning of dreams, the psychoanalyst could work out what the patient really felt or wanted.

The problem of course is that it's easy to make up "interpretations" that follows this rule, whatever the dream. If you did dream that you were happily counting your cash after failing to get a raise, Freud could simply say that your dream was wish-fulfilment - you were dreaming of what you wanted to happen, getting the raise.

But hang on, maybe you didn't want the raise, and you were happy not to get it, because it supported your desire to quit that crappy job and find a better one...

Despite all that, since reading Freud I've found myself paying more attention to my dreams (once you start it's hard to stop) and I've found that his rule does ring true: emotions in dreams are "real", and sometimes they can be important reminders of what you really feel about something.

Most of my dreams have no emotions: I see and hear stuff, but feel very little. But sometimes, maybe one time in ten, they are accompanied by emotions, often very strong ones. These always seem linked to the content of the dream, rather than just being random brain activity: I can't think of a dream in which I was scared of something that I wouldn't normally be scared of, for example.

Generally my dreams have little to do with my real life, but those that do are often the most emotional ones, and it's these that I think provide insights. For example, I've had several dreams in the past six months about running; in every case, they were very happy ones.

Until several months ago I was a keen runner but I've let this slip and got out of shape since. While awake, I've regretted this, a bit, but it wasn't until I reflected on my dreams that I realized how important running was to me and how much I regret giving it up.

While awake, we're always thinking about things on multiple levels: we don't just want X, we think "I want X" (not the same thing), and then we go on to wonder "But should I want X?", "Why do I want X?", "What about Y, would that be better?", etc. Thoughts get piled up on top of one another: it's all very cluttered.

In a dream, most of the layers go silent, and the underlying feeling comes closer to the surface. The principle is the same, in many ways, as this.

But how do I know that feelings in dreams are the "real" ones? In most respects, dreams are less real than waking stuff: we dream about all kinds of crazy stuff. And even if we accept that dreams offer a window into our "underlying" feelings, who's to say that deeper is better or more real?

Well, "buried" feelings matter whenever they're not really buried. If a desire was somehow "repressed" to the point of having no influence at all, it might as well not exist. But my feelings about running were not unconscious as such - I was aware of them before I had these dreams - but I was "repressing" them, not in any mysterious sense, but just in terms of telling myself that it wasn't a big deal, I'd start again soon, I didn't have time, etc.

The problem was that this "repression" was annoying, it was causing long-term frustration etc. In dreams, all of these mild emotions spanning several months were compressed into powerful feelings for the duration of the dream (a few minutes, although the dreams "felt like" they lasted hours).

Overall, I don't think it's possible or useful to interpret dreams as metaphorical representations in a Freudian sense (a train going into a tunnel = sex, or whatever). I suspect that dreams are more or less random activity in the visual and memory areas of the brain. But that doesn't mean they're meaningless: they're activity in your brain, so they can tell you about what you think and feel.

In Dreams

Freud's The Interpretation of Dreams is a very long book but the essential theory is very simple: dreams are thoughts. While dreaming, we are thinking about stuff, in exactly the same way as we do when awake. The difference is that the original thoughts rarely appear as such, they are transformed into weird images.

Only emotions survived unaltered. A thought about how you're angry at your boss for not giving you a raise might become a dream where you're a cop angrily chasing a bank robber, but not into one where you're a bank robber happily counting his loot. By interpreting the meaning of dreams, the psychoanalyst could work out what the patient really felt or wanted.

The problem of course is that it's easy to make up "interpretations" that follows this rule, whatever the dream. If you did dream that you were happily counting your cash after failing to get a raise, Freud could simply say that your dream was wish-fulfilment - you were dreaming of what you wanted to happen, getting the raise.

But hang on, maybe you didn't want the raise, and you were happy not to get it, because it supported your desire to quit that crappy job and find a better one...

Despite all that, since reading Freud I've found myself paying more attention to my dreams (once you start it's hard to stop) and I've found that his rule does ring true: emotions in dreams are "real", and sometimes they can be important reminders of what you really feel about something.

Most of my dreams have no emotions: I see and hear stuff, but feel very little. But sometimes, maybe one time in ten, they are accompanied by emotions, often very strong ones. These always seem linked to the content of the dream, rather than just being random brain activity: I can't think of a dream in which I was scared of something that I wouldn't normally be scared of, for example.

Generally my dreams have little to do with my real life, but those that do are often the most emotional ones, and it's these that I think provide insights. For example, I've had several dreams in the past six months about running; in every case, they were very happy ones.

Until several months ago I was a keen runner but I've let this slip and got out of shape since. While awake, I've regretted this, a bit, but it wasn't until I reflected on my dreams that I realized how important running was to me and how much I regret giving it up.

While awake, we're always thinking about things on multiple levels: we don't just want X, we think "I want X" (not the same thing), and then we go on to wonder "But should I want X?", "Why do I want X?", "What about Y, would that be better?", etc. Thoughts get piled up on top of one another: it's all very cluttered.

In a dream, most of the layers go silent, and the underlying feeling comes closer to the surface. The principle is the same, in many ways, as this.

But how do I know that feelings in dreams are the "real" ones? In most respects, dreams are less real than waking stuff: we dream about all kinds of crazy stuff. And even if we accept that dreams offer a window into our "underlying" feelings, who's to say that deeper is better or more real?

Well, "buried" feelings matter whenever they're not really buried. If a desire was somehow "repressed" to the point of having no influence at all, it might as well not exist. But my feelings about running were not unconscious as such - I was aware of them before I had these dreams - but I was "repressing" them, not in any mysterious sense, but just in terms of telling myself that it wasn't a big deal, I'd start again soon, I didn't have time, etc.

The problem was that this "repression" was annoying, it was causing long-term frustration etc. In dreams, all of these mild emotions spanning several months were compressed into powerful feelings for the duration of the dream (a few minutes, although the dreams "felt like" they lasted hours).

Overall, I don't think it's possible or useful to interpret dreams as metaphorical representations in a Freudian sense (a train going into a tunnel = sex, or whatever). I suspect that dreams are more or less random activity in the visual and memory areas of the brain. But that doesn't mean they're meaningless: they're activity in your brain, so they can tell you about what you think and feel.

Serotonin, Psychedelics and Depression

Note: This post is part of a Nature Blog Focus on hallucinogenic drugs in medicine and mental health, inspired by a recent Nature Reviews Neuroscience paper, The neurobiology of psychedelic drugs: implications for the treatment of mood disorders, by Franz Vollenweider & Michael Kometer. That article will be available, free (once you register), until September 23. For more information on this Blog Focus, see the "Table of Contents" here.

Neurophilosophy is covering the history of psychedelic psychiatry, while Mind Hacks provides a personal look at one particular drug, DMT. The Neurocritic discusses ketamine, an anesthetic with hallucinogenic properties, which is attracting a lot of interest at the moment as a treatment for depression.

Ketamine, however, is not a "classical" psychedelic like the drugs that gave the 60s its unique flavor and left us with psychedelic rock, acid house and colorful artwork. Classical psychedelics are the focus of this post.

The best known are LSD ("acid"), mescaline, found in the peyote and a few other species of cactus, and psilocybin, from "magic" mushrooms of the Psilocybe genus. Yet there are literally hundreds of related compounds. Most of them are described in loving detail in the two heroic epics of psychopharmacology, PIKHaL and TIKHaL, written by chemists and trip veterans Alexander and Ann Shulgin.

The chemistry of psychedelics is closely linked with that of depression and antidepressants. All classical psychedelics are 5HT2A receptor agonists. Most of them have other effects on the brain as well, which contribute to the unique effects of each drug, but 5HT2A agonism is what they all have in common.

5HT2A receptors are excitatory receptors expressed throughout the brain, and are especially dense in the key pyramidal cells of the cerebral cortex. They're normally activated by serotonin (5HT), which is the neurotransmitter that's most often thought of as being implicated in depression. The relationship between 5HT and mood is very complicated, and depression isn't simply a disorder of "low serotonin", but there's strong evidence that it is involved.

There's one messy detail, which is that not quite all 5HT2A agonists are hallucinogenic. Lisuride, a drug used in Parkinson's disease, is closely related to LSD, and is a strong 5HT2A agonist, but it has no psychedelic effects. It's recently been shown that LSD and lisuride have different molecular effects on cortical cells, even though they act on the same receptor - in other words, there's more to 5HT2A than simply turning it "on" and "off".

*

How could psychedelics help to treat mental illness? On the face of it, the acute effects of these drugs - hallucinations, altered thought processes and emotions - sound rather like the symptoms of mental illness themselves, and indeed psychedelics have been referred to as "psychotomimetic" - mimicking psychosis.

There are two schools of thought here: psychological and neurobiological.

The psychological approach ruled the first wave of psychedelic psychiatry, in the 50s and 60s. Psychiatry, especially in America, was dominated by Freudian theories of the unconscious. On this view, mental illness was a product of conflicts between unconscious desires and the conscious mind. The symptoms experienced by a particular patient were distressing, of course, but they also provided clues to the nature of their unconscious troubles.

It was tempting to see the action of psychedelics as a weakening of the filters which kept the unconscious, unconscious - allowing repressed material to come into awareness. The only other time this happened, according to Freud, was during dreams. That's why Freud famously called the interpretation of dreams the "royal road to the unconscious".

Psychedelics offered analysts the tantalizing prospect of confronting the unconscious face-to-face, while awake, instead of having to rely on the patient's memory of their previous dreams. To enthusiastic Freudians, this promised to revolutionize therapy, in the same way that the x-ray had done so much for surgery. The "dreamlike" nature of many aspects of the psychedelic experience seemed to confirm this.

Not all psychedelic therapists were orthodox Freudians, however. There were plenty of other theories in circulation, many of them inspired by the theorists' own drug experiences. Stanislav Grof, Timothy Leary and others saw the psychedelic state of consciousness as the key to attaining spiritual, philosophical and even mystical insights, whether one was "ill" or "healthy" - and indeed, they often said that mental "illness" was itself a potential source of spiritual growth.

Like many things, psychiatry has changed since the 60s. Psychotherapy is currently dominated by cognitive-behavioural (CBT) theory, and Freudian ideas have gone distinctly out of fashion. It remains to be seen what CBT would make of LSD, but the basic idea - that carefully controlled use of drugs could help patients to "break through" psychological barriers to treatment - seems likely to remain at the heart of their continued use.

*

The other view is that these drugs could have direct biological effects which lead to improvements in mood. Repeated use of LSD, for example, has been shown to rapidly induce down-regulation of 5HT2A receptors. Presumably, this is the brain's way of "compensating" for prolonged 5HT2A activation. This is probably why tolerance to the effects of psychedelics rapidly develops, something that's long been known (and regretted) by heavy users.

Vollenweider and Kometeris note that this is interesting, because 5HT2A blockers are used as antidepressants - the drugs nefazadone and mirtazapine are the best known today, but most of the older tricyclic antidepressants are also 5HT2A antagonists. Atypical antipsychotics, which are also used in depression, are potent 5HT2A antagonists as well.

So indirectly suppressing 5HT2A might be one biological mechanism by which psychedelics improve mood. However, questions remain about how far this could explain any therapeutic effects of these drugs. Psychedelic-induced 5HT2A down-regulation is presumably temporary - and if all we need to do is to knock out 5HT2A, it would surely be easiest to just use an antagonist...

Vollenweider FX, & Kometer M (2010). The neurobiology of psychedelic drugs: implications for the treatment of mood disorders. Nature Reviews Neuroscience, 11 (9), 642-51 PMID: 20717121

Serotonin, Psychedelics and Depression

Note: This post is part of a Nature Blog Focus on hallucinogenic drugs in medicine and mental health, inspired by a recent Nature Reviews Neuroscience paper, The neurobiology of psychedelic drugs: implications for the treatment of mood disorders, by Franz Vollenweider & Michael Kometer. That article will be available, free (once you register), until September 23. For more information on this Blog Focus, see the "Table of Contents" here.

Neurophilosophy is covering the history of psychedelic psychiatry, while Mind Hacks provides a personal look at one particular drug, DMT. The Neurocritic discusses ketamine, an anesthetic with hallucinogenic properties, which is attracting a lot of interest at the moment as a treatment for depression.

Ketamine, however, is not a "classical" psychedelic like the drugs that gave the 60s its unique flavor and left us with psychedelic rock, acid house and colorful artwork. Classical psychedelics are the focus of this post.

The best known are LSD ("acid"), mescaline, found in the peyote and a few other species of cactus, and psilocybin, from "magic" mushrooms of the Psilocybe genus. Yet there are literally hundreds of related compounds. Most of them are described in loving detail in the two heroic epics of psychopharmacology, PIKHaL and TIKHaL, written by chemists and trip veterans Alexander and Ann Shulgin.

The chemistry of psychedelics is closely linked with that of depression and antidepressants. All classical psychedelics are 5HT2A receptor agonists. Most of them have other effects on the brain as well, which contribute to the unique effects of each drug, but 5HT2A agonism is what they all have in common.

5HT2A receptors are excitatory receptors expressed throughout the brain, and are especially dense in the key pyramidal cells of the cerebral cortex. They're normally activated by serotonin (5HT), which is the neurotransmitter that's most often thought of as being implicated in depression. The relationship between 5HT and mood is very complicated, and depression isn't simply a disorder of "low serotonin", but there's strong evidence that it is involved.

There's one messy detail, which is that not quite all 5HT2A agonists are hallucinogenic. Lisuride, a drug used in Parkinson's disease, is closely related to LSD, and is a strong 5HT2A agonist, but it has no psychedelic effects. It's recently been shown that LSD and lisuride have different molecular effects on cortical cells, even though they act on the same receptor - in other words, there's more to 5HT2A than simply turning it "on" and "off".

*

How could psychedelics help to treat mental illness? On the face of it, the acute effects of these drugs - hallucinations, altered thought processes and emotions - sound rather like the symptoms of mental illness themselves, and indeed psychedelics have been referred to as "psychotomimetic" - mimicking psychosis.

There are two schools of thought here: psychological and neurobiological.

The psychological approach ruled the first wave of psychedelic psychiatry, in the 50s and 60s. Psychiatry, especially in America, was dominated by Freudian theories of the unconscious. On this view, mental illness was a product of conflicts between unconscious desires and the conscious mind. The symptoms experienced by a particular patient were distressing, of course, but they also provided clues to the nature of their unconscious troubles.

It was tempting to see the action of psychedelics as a weakening of the filters which kept the unconscious, unconscious - allowing repressed material to come into awareness. The only other time this happened, according to Freud, was during dreams. That's why Freud famously called the interpretation of dreams the "royal road to the unconscious".

Psychedelics offered analysts the tantalizing prospect of confronting the unconscious face-to-face, while awake, instead of having to rely on the patient's memory of their previous dreams. To enthusiastic Freudians, this promised to revolutionize therapy, in the same way that the x-ray had done so much for surgery. The "dreamlike" nature of many aspects of the psychedelic experience seemed to confirm this.

Not all psychedelic therapists were orthodox Freudians, however. There were plenty of other theories in circulation, many of them inspired by the theorists' own drug experiences. Stanislav Grof, Timothy Leary and others saw the psychedelic state of consciousness as the key to attaining spiritual, philosophical and even mystical insights, whether one was "ill" or "healthy" - and indeed, they often said that mental "illness" was itself a potential source of spiritual growth.

Like many things, psychiatry has changed since the 60s. Psychotherapy is currently dominated by cognitive-behavioural (CBT) theory, and Freudian ideas have gone distinctly out of fashion. It remains to be seen what CBT would make of LSD, but the basic idea - that carefully controlled use of drugs could help patients to "break through" psychological barriers to treatment - seems likely to remain at the heart of their continued use.

*

The other view is that these drugs could have direct biological effects which lead to improvements in mood. Repeated use of LSD, for example, has been shown to rapidly induce down-regulation of 5HT2A receptors. Presumably, this is the brain's way of "compensating" for prolonged 5HT2A activation. This is probably why tolerance to the effects of psychedelics rapidly develops, something that's long been known (and regretted) by heavy users.

Vollenweider and Kometeris note that this is interesting, because 5HT2A blockers are used as antidepressants - the drugs nefazadone and mirtazapine are the best known today, but most of the older tricyclic antidepressants are also 5HT2A antagonists. Atypical antipsychotics, which are also used in depression, are potent 5HT2A antagonists as well.

So indirectly suppressing 5HT2A might be one biological mechanism by which psychedelics improve mood. However, questions remain about how far this could explain any therapeutic effects of these drugs. Psychedelic-induced 5HT2A down-regulation is presumably temporary - and if all we need to do is to knock out 5HT2A, it would surely be easiest to just use an antagonist...

Vollenweider FX, & Kometer M (2010). The neurobiology of psychedelic drugs: implications for the treatment of mood disorders. Nature Reviews Neuroscience, 11 (9), 642-51 PMID: 20717121

Inception for Dummies

If you haven't watched Inception yet, don't read this post. It's great and I don't want to spoil it for you. So stop. You didn't though, did you, you're still reading this right now. Well, I warned you.

Inception as everyone knows is about people who can hack into other people's dreams to access their subconcious. The plot concerns their attempts to achieve, well, inception - putting an idea into someone's mind, which makes what they usually do, stealing secret ideas, seem easy by comparison.

The problem is that it's easy to plant an idea, but the victim always knows that it's an external imposition - they don't really believe it. Leonardo DiCaprio comes up with the plan of going into the victim's subconcious's subconcious, and planting an emotional idea about his father, in order to lead him to conclude, on his own, that he should break up his father's business empire. I'm not sure what Freud would have thought of this plan.

Could you actually do this? Well. Hacking into people's dreams is high fantasy: we have absolutely no idea how you'd do that, and in the movie the only explanation we get is that it involves fancy machines and unspecified drugs. It's safe to say no-one will be gatecrashing your dream party any time soon.

But here's one way to achieve the same kind of effect, inspired by two recent papers: this one that I wrote about in my last post, finding that electrical stimulation of the hippocampus produces temporary amnesia, and this one covered at Neurophilosophy, finding that stimulating a mouse's lateral amygdala at the same time as playing it a noise makes it fear that noise.

Simple fear conditioning happens in the amygdala, not the hippocampus (although conditioned fear to some partiuclarly complex stimuli, like places, does.) So assuming you were a neurosurgeon with a desire to do some inception and no ethical scruples whatsoever, here's what you might decide to do.

Knock your victim out with a sedative. Keep them unconscious while you implant electrodes in their hippocampus and their amygdala. Wake them up, but make sure that you constantly stimulate their hippocampus to disrupt it, from the moment they awake. This will leave them fully aware, but will mean they'll have no subsequent concious memory of what you do, because such concious declarative memories depend upon the hippocampus.

Now, you condition them to fear something, by showing it to them whilst stimulating their lateral amygdala. (To be honest, you could just give them a slap in the face and it would probably be just as effective - but that would be a bit unrefined. This is a high-tech evil medical procedure, not a common punch-up.) Maybe you could make them scared of the face of a business rival who you don't want them to cut a deal with. Or you could make a terrorist leader abhor the symbols of his own ideology. The possibilities are endless.

Once you're done, sedate them again and return them to their house. Yeah, you'd have to do this all in the course of one night, but no-one said Inception was going to be easy. With any luck, they'll wake up with no concious recollection of anything, but with the emotional conditioning still intact.

The lack of memory is of course crucial: if they remembered what had happened, they'd realize that the conditioning was an external imposition, and wouldn't be swayed by it. And they'd bust you to the cops, obviously. But without that concious knowledge as to the true source of the feelings, they'd have no alternative interpretation of the fear they now feel - they'd take it as their own, and really start to dislike whatever it was you'd made them afraid of, constructing elaborate rationalizations along the way. The dream is real...

Inception for Dummies

If you haven't watched Inception yet, don't read this post. It's great and I don't want to spoil it for you. So stop. You didn't though, did you, you're still reading this right now. Well, I warned you.

Inception as everyone knows is about people who can hack into other people's dreams to access their subconcious. The plot concerns their attempts to achieve, well, inception - putting an idea into someone's mind, which makes what they usually do, stealing secret ideas, seem easy by comparison.

The problem is that it's easy to plant an idea, but the victim always knows that it's an external imposition - they don't really believe it. Leonardo DiCaprio comes up with the plan of going into the victim's subconcious's subconcious, and planting an emotional idea about his father, in order to lead him to conclude, on his own, that he should break up his father's business empire. I'm not sure what Freud would have thought of this plan.

Could you actually do this? Well. Hacking into people's dreams is high fantasy: we have absolutely no idea how you'd do that, and in the movie the only explanation we get is that it involves fancy machines and unspecified drugs. It's safe to say no-one will be gatecrashing your dream party any time soon.

But here's one way to achieve the same kind of effect, inspired by two recent papers: this one that I wrote about in my last post, finding that electrical stimulation of the hippocampus produces temporary amnesia, and this one covered at Neurophilosophy, finding that stimulating a mouse's lateral amygdala at the same time as playing it a noise makes it fear that noise.

Simple fear conditioning happens in the amygdala, not the hippocampus (although conditioned fear to some partiuclarly complex stimuli, like places, does.) So assuming you were a neurosurgeon with a desire to do some inception and no ethical scruples whatsoever, here's what you might decide to do.

Knock your victim out with a sedative. Keep them unconscious while you implant electrodes in their hippocampus and their amygdala. Wake them up, but make sure that you constantly stimulate their hippocampus to disrupt it, from the moment they awake. This will leave them fully aware, but will mean they'll have no subsequent concious memory of what you do, because such concious declarative memories depend upon the hippocampus.

Now, you condition them to fear something, by showing it to them whilst stimulating their lateral amygdala. (To be honest, you could just give them a slap in the face and it would probably be just as effective - but that would be a bit unrefined. This is a high-tech evil medical procedure, not a common punch-up.) Maybe you could make them scared of the face of a business rival who you don't want them to cut a deal with. Or you could make a terrorist leader abhor the symbols of his own ideology. The possibilities are endless.

Once you're done, sedate them again and return them to their house. Yeah, you'd have to do this all in the course of one night, but no-one said Inception was going to be easy. With any luck, they'll wake up with no concious recollection of anything, but with the emotional conditioning still intact.

The lack of memory is of course crucial: if they remembered what had happened, they'd realize that the conditioning was an external imposition, and wouldn't be swayed by it. And they'd bust you to the cops, obviously. But without that concious knowledge as to the true source of the feelings, they'd have no alternative interpretation of the fear they now feel - they'd take it as their own, and really start to dislike whatever it was you'd made them afraid of, constructing elaborate rationalizations along the way. The dream is real...

The Fall of Freud

The works of Sigmund Freud were enormously influential in 20th century psychiatry, but they've now been reduced to little more than a fringe belief system. Armed with the latest version of my PubMed history script, and inspired by this classic gnxp post on the death of Marxism, postmodernism, and other stupid academic fads I decided to see how this happened.

As you can see, the number of published scientific papers related to Freud-y search terms like psychoanalytic has flat-lined for the past 50 years. That represents a serious collapse of influence, given the enormous expansion in the amount of research being published over this time.

Since 1960 the number of papers on schizophrenia has risen by a factor of 10 and anxiety by a factor of 80 (sic). The peak of Freud's fame was 1968, when almost as many papers referenced psychoanalytic (721) as did schizophrenia (989), and it was more than half as popular as antidepressants (1372). Today it's just 10% of either. Proportionally speaking, psychoanalysis has gone out with a whimper, though not a bang.

The rise of Cognitive Behavioral Therapy (CBT), however, is even more dramatic. From being almost unheard until the late 80's, it overtook psychoanalytic in 1993, and it's now more popular than antipsychotics and close on the heels of antidepressants.

What's going to happen in the future? If there is to be a struggle for influence it looks set to be fought between CBT and biological psychiatry, if only because they're pretty much the only games left in town. Yet one of the reasons behind CBT's widespread appeal is that it hasn't thus far overtly challenged biology, has adopted the methods of medicine (clinical trials etc.), and has presented itself as being useful as well as medication rather than instead of it.

One of the few exceptions was Richard Bentall's book Madness Explained (2003) in which he criticized psychiatry and presented a cognitive-behavioural alternative to orthodox biological theories of schizophrenia and bipolar disorder. Bentall remains on the radical wing of the CBT community but in the coming decades this kind of thing may become more common. Only time will tell...

The Fall of Freud

The works of Sigmund Freud were enormously influential in 20th century psychiatry, but they've now been reduced to little more than a fringe belief system. Armed with the latest version of my PubMed history script, and inspired by this classic gnxp post on the death of Marxism, postmodernism, and other stupid academic fads I decided to see how this happened.

As you can see, the number of published scientific papers related to Freud-y search terms like psychoanalytic has flat-lined for the past 50 years. That represents a serious collapse of influence, given the enormous expansion in the amount of research being published over this time.

Since 1960 the number of papers on schizophrenia has risen by a factor of 10 and anxiety by a factor of 80 (sic). The peak of Freud's fame was 1968, when almost as many papers referenced psychoanalytic (721) as did schizophrenia (989), and it was more than half as popular as antidepressants (1372). Today it's just 10% of either. Proportionally speaking, psychoanalysis has gone out with a whimper, though not a bang.

The rise of Cognitive Behavioral Therapy (CBT), however, is even more dramatic. From being almost unheard until the late 80's, it overtook psychoanalytic in 1993, and it's now more popular than antipsychotics and close on the heels of antidepressants.

What's going to happen in the future? If there is to be a struggle for influence it looks set to be fought between CBT and biological psychiatry, if only because they're pretty much the only games left in town. Yet one of the reasons behind CBT's widespread appeal is that it hasn't thus far overtly challenged biology, has adopted the methods of medicine (clinical trials etc.), and has presented itself as being useful as well as medication rather than instead of it.

One of the few exceptions was Richard Bentall's book Madness Explained (2003) in which he criticized psychiatry and presented a cognitive-behavioural alternative to orthodox biological theories of schizophrenia and bipolar disorder. Bentall remains on the radical wing of the CBT community but in the coming decades this kind of thing may become more common. Only time will tell...

Why Do We Dream?

A few months ago, I asked Why Do We Sleep?

That post was about sleep researcher Jerry Siegel, who argues that sleep evolved as a state of "adaptive inactivity". According to this idea, animals sleep because otherwise we'd always be active, and constant activity is a waste of energy. Sleeping for a proportion of the time conserves calories, and also keeps us safe from nocturnal predators etc.

Siegel's theory in what we might call minimalist. That's in contrast to other hypotheses which claim that sleep serves some kind of vital restorative biological function, or that it's important for memory formation, or whatever. It's a hotly debated topic.

But Siegel wasn't the first sleep minimalist. J. Allan Hobson and Robert McCarley created a storm in 1977 with The Brain As A Dream State Generator; I read somewhere that it provoked more letters to the Editor in the American Journal of Psychiatry than any other paper in that journal.

Hobson and McCarley's article was so controversial because they argued that dreams are essentially side-effects of brain activation. This was a direct attack on the Freudian view that we dream as a result of our subconscious desires, and that dreams have hidden meanings. Freudian psychoanalysis was incredibly influential in American psychiatry in the 1970s.

Freud believed that dreams exist to fulfil our fantasies, often though not always sexual ones. We dream about what we'd like to do - except we don't dream about it directly, because we find much of our desires shameful, so our minds disguise the wishes behind layers of metaphor etc. "Steep inclines, ladders and stairs, and going up or down them, are symbolic representations of the sexual act..." Interpreting the symbolism of dreams can therefore shed light on the depths of the mind.

Hobson and McCarley argued that during REM sleep, our brains are active in a similar way to when we are awake; many of the systems responsible for alertness are switched on, unlike during deep, dreamless, non-REM sleep. But of course during REM there is no sensory input (our eyes are closed), and also, we are paralysed: an inhibitory pathway blocks the spinal cord, preventing us from moving, except for our eyes - hence why it's Rapid Eye Movement sleep.

Dreams are simply a result of the "awake-like" forebrain - the "higher" perceptual, cognitive and emotional areas - trying to make sense of the input that it's receiving as a result of waves of activation arising from the brainstem. A dream is the forebrain's "best guess" at making a meaningful story out of the assortment of sensations (mostly visual) and concepts activated by these periodic waves. There's no attempt to disguise the shameful parts; the bizarreness of dreams simply reflects the fact that the input is pretty much random.

Hobson and McCarley proposed a complex physiological model in which the activation is driven by the giant cells of the pontine tegmentum. These cells fire in bursts according to a genetically hard-wired rhythm of excitation and inhibition.

The details of this model are rather less important than the fact that it reduces dreaming to a neurological side effect. This doesn't mean that the REM state has no function; maybe it does, but whatever it is, the subjective experience of dreams serves no purpose.

A lot has changed since 1977, but Hobson seems to have stuck by the basic tenets of this theory. A good recent review came out in Nature Neuroscience last year, REM sleep and dreaming. In this paper Hobson proposes that the function of REM sleep is to act as a kind of training system for the developing brain.

The internally-generated signals that arise from the brainstem (now called PGO waves) during REM help the forebrain to learn how to process information. This explains why we spend more time in REM early in life; newborns have much more REM than adults; in the womb, we are in REM almost all the time. However, these are not dreams per se because children don't start reporting experiencing dreams until about the age of 5.

Protoconscious REM sleep could therefore provide a virtual world model, complete with an emergent imaginary agent (the protoself) that moves (via fixed action patterns) through a fictive space (the internally engendered environment) and experiences strong emotion as it does so.

This is a fascinating hypothesis, although very difficult to test, and it begs the question of how useful "training" based on random, meaningless input is.

While Hobson's theory is minimalist in that it reduces dreams, at any rate in adulthood, to the status of a by-product, it doesn't leave them uninteresting. Freudian dream re-interpretation is probably ruled out ("That train represents your penis and that cat was your mother", etc.), but if dreams are our brains processing random noise, then they still provide an insight into how our brains process information. Dreams are our brains working away on their own, with the real world temporarily removed.

Of course most dreams are not going to give up life-changing insights. A few months back I had a dream which was essentially a scene-for-scene replay of the horror movie Cloverfield. It was a good dream, scarier than the movie itself, because I didn't know it was a movie. But I think all it tells me is that I was paying attention when I watched Cloverfield.

On the other hand, I have had several dreams that have made me realize important things about myself and my situation at the time. By paying attention to your dreams, you can work out how you really think, and feel, about things, what your preconceptions and preoccupations are. Sometimes.

Hobson JA, & McCarley RW (1977). The brain as a dream state generator: an activation-synthesis hypothesis of the dream process. The American journal of psychiatry, 134 (12), 1335-48 PMID: 21570

Hobson, J. (2009). REM sleep and dreaming: towards a theory of protoconsciousness Nature Reviews Neuroscience, 10 (11), 803-813 DOI: 10.1038/nrn2716