There was a news item on the BBC recently about a trial of cannabis in patients with Parkinson’s disease who also have visual hallucinations. Parkinson’s disease is undoubtedly a brain disorder but are visual hallucinations also abnormal? One such patient was presented, an elderly man who had hallucinations – they might better be called visions – of his late wife and their deceased pet dog. He also described how he once found his house full of strangers as if it was a party: he didn’t know any of those people, they ignored him, and he could walk right through them.

These visions, however, were regarded as something to be got rid off or suppressed; they were called a psychosis.

I take the concept of psychosis to mean a mental state in which the person is out of touch with reality, but what is reality? Is it the same as consciousness? If this is the case, we all suffer a psychosis every night when we dream. Indeed, the patient said he often experienced these manifestation when waking up from sleep.

One could define psychosis, then, as the situation when someone so affected doesn’t know the difference between outer reality and his or her inner life with its visual and/or auditory hallucinations. One could also define psychosis as a state of mind in which the patient believes that their inner life is reality. This can be very frightening and disturbing – there are a number of autobiographical accounts of this situation. Some dreams or nightmares can also be frightening and disturbing and we usually don’t know that we’ve been dreaming until we wake up. Similarly, the person suffering from what we call a psychosis only knows he or she has had such an episode after recovery.

As the patient related to the BBC, he thought he really saw his wife, his dog, and the people in his house: he believed they were there at the time and it was only afterwards, when they vanished, that he realised they were not real.

One current medical textbook on Parkinson’s disease notes: ‘The adverse effects of antiparkinson medications, the dopamine agonists in particular, are probably the most important cause of psychosis in patients with Parkinson’s disease.’ Obviously, something is going on in the brain to produce these phenomena, just as something is happening in the brain to produce what we call consciousness, but we don’t know what this is.

An incredible amount of activity is going on in the brain all the time while we are alive, but the tools we have for investigating it (fMRIs, PET scans, etc.) are too crude to tell us anything more than that certain parts of the brain are more or less active in certain states of mind or when doing things like mental arithmetic. There are no diagnostic findings differentiating someone deemed normal from someone suffering distressing symptoms that we call depression, schizophrenia, obsessive-compulsive disorder, and the like.

On the other hand, the symptom of epilepsy clearly does result from a brain disorder with abnormal activity usually in the frontal or parietal lobe. The main feature of grand mal epilepsy is that the sufferer loses consciousness. But even in this situation our available investigative tools don’t tell us very much. For example, an EEG (brainwave test) is not diagnostic; it needs to be correlated with physical observations, in particular, the description by an observer of someone suffering a fit. A normal EEG does not rule out epilepsy and many EEG abnormalities are non-specific.

How much more mysterious and inexplicable, then, are certain states of mind labeled as so-and-so disorders, such as major depressive disorder, bi-polar disorder, etc.

In the case of the above-mentioned patient with Parkinson’s disease who experienced visions, rather than regarding them as abnormal, we might ask what their value was. He saw figures of importance to him: his beloved deceased wife and dog, and the people in his house could be representative of his yearning to be active and fully involved in life again. What was the psychological significance of these visions? What did he feel about them? Some were distressing, he said. Of course they were – that was why he saw them. If they meant nothing there would have been no point in having them. It might have been helpful to enquire what other night-time dreams he had, since dreams, similarly, are manifestations from the unconscious.

What is consciousness anyway?
Professor Susan Blackmore, the author of a book called Consciousness: A Very Short Introduction, (Oxford University Press, 2017), concludes that consciousness is an illusion. She says we’re only conscious when we’re thinking about whether we are and likens this to trying to open the fridge door quickly enough to see whether the light is on all the time. If this is her view the book is misnamed: it ought to have been called ‘The Illusion of Consciousness: A Very Short Introduction.’

Consciousness is a phenomenon of which most people would say that they know what it is but find it very difficult to describe, let alone explain. A common-sense definition would be self-awareness. We are aware, most of the time, of our sensory impressions: what we see, hear, smell, feel by touch, etc. Consciousness, however, is much more than our sensory impressions. Obviously, a self-driving car cannot be said to be conscious, though in some ways it behaves as if it is: the computer tells it to stop at a red light, and so on.

The essential difference between machines and ourselves is that there is an entity which is aware of having the sensory impressions and much else besides, such as feelings, emotions, and imagination. It is the awareness that we ‘have’ these impressions, feelings, etc., that constitutes consciousness. If a self-driving car were involved in an accident and the bodywork slightly damaged it would carry on driving itself and wouldn’t be conscious of the minor damage. On the other hand, humans and other vertebrates, to say nothing of ‘lower’ forms of life, can also feel pain and fear. Thus, the centre of our being, our ‘self’, has the capacity to be aware of having emotions and feelings as well as sensory impressions, and we might say it is this mental activity, at a minimum, that constitutes consciousness.

The great Swiss psychiatrist, C. G. Jung, developed the idea of consciousness a lot further. His ideas are based on empirical observations of his patients and himself, apart from many other sources. Consciousness is only a small part of what Jung calls the psyche, the totality of our mental apparatus. By far the larger part, as the submerged part of an iceberg is to that above the surface of the sea, is the unconscious. This functions autonomously and gives rise to dreams, fantasies, imagination – and visions. Jung’s view is that dreams have a balancing or compensatory function between the unconscious and conscious activities of the psyche. (This is a vast subject of which the preceding is the merest hint. The interested reader is referred to Jung’s own voluminous output or to one of the many available introductory accounts of his work.)

Treatment-resistant depression
Similar to the narrow-minded view of the psychiatrists involved with the above-mentioned patient, is the approach used in what is called treatment-resistant depression – an unfortunate expression since it sounds like blaming the patient for refusing to get better.

This commonly used term means that someone remains depressed in spite of having been subjected to at least two ‘antidepressant’ drugs: none helps the patient to any significant extent, or at all. Nonetheless, the implication is that the patient’s symptoms should or might be amenable to drug treatment – if only we could find the right one! But since the number of approved drugs for depression is limited, we need to try experimental ones such as the hallucinogenic psilocybin, or even physical methods. Electro-convulsive therapy (ECT) is still occasionally used empirically for severe depression; magnetic and electrical stimulation have also been tried, as has deep brain stimulation. This last-mentioned involves surgically implanting an electrode into the brain to send a small signal to counteract brain ‘circuits’ believed to be associated with depressive symptoms – an heroic measure which appears promising in the one patient in whom it has been tried so far.

Depression refers to distressing thoughts and feelings. Of course, certain parts of the brain are active during any mental activity but the assumption here is that there is a primary disturbance in the part or parts of the brain that cause or are involved in depression, and therefore it might be treatable if we could intervene somehow to block or otherwise counteract these presumed dysfunctional brain activities. Such an idea, however, is purely speculative, and it is hubristic to assume that these crude manipulations can really cure depression.

A better approach, I believe, as in the case of the Parkinson’s disease patient who saw visions, would be to try to help patients understand the sources of their distress and perhaps to find meaning in them – they don’t happen in a vacuum. Thus, they may be able to resolve or at least to come to terms with the underlying conflicts and traumas.

Drugs and physical methods should be used as a last resort. This is because ‘there is no state of the brain, nor even particular features of brain activity, that corresponds to depression or anxiety, or any other mental state.’  Further, taking psychiatric drug ‘drives the body into an abnormal and biologically stressed state.’ These effects, which typically include sedation and emotional blunting, although they may be regarded as preferable by patients or others to the undrugged state, are in no sense a cure. (The quotations are from A Straight Talking Introduction to Psychiatric Drugs by Joanna Moncrieff, PCCS Books, 2020.)

The picture is of Sigmund Freud’s couch at the Freud Museum, London.

Text © Gabriel Symonds