Brief Notes

Welcome to a collection of notes on new research and ideas from the world of neuroscience. I shall be adding fresh notes on a regular basis. New entries come first, so I suggest you start at the bottom of the page and scroll upwards.

Crocodile brains may be more than reptilian

Reptiles are meant to have reptilian brains that are only good for catching prey, laying eggs and leaving them to their fate. Mammalian brain enhancements such as taking care of the young are meant to be the preserve of mammals. But biology is full of exceptions to the rule, and an exception to the reptilian brain rule is provided by a crocodile called Cassius, a bona fide reptile. Cassius lived in captivity on an island near Cairns where his owner, George Craig, fed him for 37 years. The eggs of captive crocs are removed to stop male crocs eating them, but when George accidentally left one behind one day, it hatched and he found it sitting on Cassius’s head. Cassius looked after this female hatchling for 14 years, even sharing his food with her. And another exception to the reptilian brain rule: when George had to leave the island to go into an old folks home, Cassius started refusing food and died a few weeks later – suggesting bonding, attachment and the pain of loss. A croc with CARE and GRIEF emotional systems (that are meant to be mammalian)? Conclusion: take crystal-clear models such as the triune brain one of reptilian, mammalian and human brains with a pinch of salt. Emily Wind, theguardian.com November 2024

Treating depression at home with transcranial electrical stimulation

Following on from the love trauma note below (June 2024), now it’s reported that depression has been found to improve with transcranial direct current stimulation. The person can self-administer the treatment by wearing a headset at home. The result is meant to be that frontal lobe neurons fire more readily. If you’re alarmed at the idea of electrical brain treatment, you can relax: the current is at least 400 times weaker than that used in ECT (electro-convulsive therapy). theguardian.com October 2024

‘Connectonomics’: the mind-boggling complexity of a fruit fly brain

The brain of a fruit fly is the size of a poppy seed, but it’s packed with some 140,000 neurons and over 50 million synapses, and the neurons come in over 8,000 different types. So has found Sebastian Seung, a neuroscience professor at Princeton University and author of (the very readable) ‘Connectome’, his term for what neuroscientists usually call a neural ‘wiring diagram’. His team has mapped every single connection in this tiny brain. To do so involved slicing a female (why not male?) fruit fly brain into 7,000 slivers, and inspecting each one in an electron microscope to reveal bits of neural biology as small as four-millionths of a millimetre wide (get your head around that sort of scale!). Seung says “connectonomics is going to be a rapid acceleration of the way in which we do neuroscience”. His next project is to map a mouse brain, which will keep his team busy for the next five to ten years. How about a human brain? Well, being a million times more complex than a fruit fly brain (is that all?), it defeats the capabilities of current technology - what a relief. Ian Sample, the guardian.com October 2024 & nature.com October 2024

Time, the hemispheres and climate change

Iain McGilchrist writes that the left hemisphere can deal with the comparative positioning of points in time, but not their extent or depth: “it cannot deal with the extended continuous flow of time”. Might this be why humanity, inhabiting a world increasingly oriented towards the left hemisphere, seems to have a problem judging the likely timescale of climate change and therefore the need to act now? People can see that changes will happen in the future, but today is the present, and the future… well, it can safely be ignored for now, lulling us into a dangerous sense of complacency. It’s our right hemispheres that have a sense of time, of duration, and that are better able to assess the timescale of climate change and the need to act now. Hence, those who lean into their right hemispheres may be the ones who feel most alarmed about the future and our collective failure to act. According to McGilchrist, our right hemispheres are in touch with reality, while our left hemispheres live in a virtual model of the real world (think language, concepts, theories, computers). The Matter with Things, volume 1, page 81

Brain changes during pregnancy

A report of a scientist at the University of California, Irvine, who agreed to her colleagues taking a series of MRI scans of her brain as she went through the stages of pregnancy. There were some marked changes, most noticeably a steady decrease in grey matter (local synaptic connections) volume and thickness in regions doing social cognition. This is thought to reflect the pruning and sculpting of neural pathways as neuroplasticity responds to changing circumstances, perhaps similar to cortical thinning that happens in puberty. Another finding was a peak in white matter (long distance synaptic connections) at the end of the second trimester, but these then dropped back down. And of course there were big changes in levels of hormones, especially oestrogen and progesterone. Some changes were still present two years after giving birth. All of which tells us… maybe not a lot at this point. More pregnant candidates for scanning needed! Any comments from mothers with relevant personal experience? Ian Sample, theguardian.com September 2024

Racism and the hemispheres

Racism may start at a subcortical level with fear of the other who doesn’t look like I do. But entrenched racist attitudes surely belong in the left hemisphere. Racism categorises people, is aggressive, and is repetitive, running in well-worn grooves, the same thing every time. Overcoming racism requires the right hemisphere’s capacity for sensing the person behind the racial or ethnic exterior, and then connecting with them in this real, human place. June 2024

Treating ‘love trauma syndrome’ with transcranial electrical stimulation

Relief from the emotional pain of ending a relationship is possible with the use of headsets that deliver transcranial direct current stimulation, according to a study published in the Journal of Psychiatric Research. Stimulating the dorsolateral prefrontal cortex works better than stimulating the ventrolateral prefrontal cortex – don’t ask me why – and you only need to wear the headset twice a day for 20 minutes at a time. Similar headsets, costing a modest £400, are being trialled for treating mild depression. Is this the beginning of a whole new line of psychological treatment? Is it a good idea? NB. this sort of emotional pain should not be described as trauma, in my opinion. Caroline Davis, theguardian.com June 2024

Big numbers in a cubic millimetre of your brain

A report from collaboration between Harvard and Google on what they found in a cubic millimetre of cortex removed from a patient with severe epilepsy during surgery. An electron microscope sliced it into 5,000 wafers a thousand times thinner than a human hair. It found 57,000 neurons, 150 million synapses, and 23 centimetres of blood vessels. More than 96% of the neurons made one connection with another neuron, 3% made two connections, and the rest made up to 50 connections with a nearby neuron (these neurons must have been connecting with many others, but at this rate of connectivity with each one). Some neurons had axons that were gathered in whorls, as if they had been going round and round a roundabout before finding the exit. All this in just one tiny cubic millimetre – talk about complexity! Apparently, the next Harvard-Google project is to reconstruct the wiring of the whole of a mouse brain – this is extremely ambitious, it hasn’t been done yet. Ian Sample, theguardian.com May 2024

Conflict, trauma, and right brain fragmentation

War leaves trauma in its wake, and trauma involves a fragmenting of the integrative functions of the brain and of the right brain in particular - such as keeping body and environment, cognition and affect, in sync. If trauma is not healed, there are consequences: fear and anxiety, hyper-vigilance, dissociated rage, and the inability to see the big picture because of the bias towards perceiving threats. How much human conflict is fuelled by unresolved trauma from past conflict? Fragmented right hemispheres are not well disposed to live in peace, the integration of self and other having broken down. Maybe not all conflict is the result of trauma, but where unresolved trauma lurks, fighting may be more likely to erupt - perhaps it’s even inevitable in the long run. What if we approached conflict situations by thinking of unresolved trauma and offering help to deal with it? What if we learnt to recognise the signs of unresolved trauma before further fighting kicks off? April 2024

Vorfreude, reward, and the SEEKING system

The German concept of vorfreude translates as the anticipation of joy, in contrast to the better known schadenfreude. Vorfreude is the good feeling associated with what gets called the reward system – which is a misnomer because it’s about the anticipation of reward and the positive feelings you get from a blast of dopamine. The satisfaction of consuming whatever it is you find rewarding has more to do with endorphins. Of course, satisfaction can lead to wanting more and therefore more anticipation and another shot of dopamine (and hence addiction). Vorfreude and the reward system are best described by Jaak Panksepp’s concept of SEEKING. This is the most fundamental of the seven emotional systems shared by all mammals – who seek shelter, food, a mate. Humans have evolved it into more things such as going shopping and seeking meaning in life. SEEKING, fuelled by dopamine, feels good - and the Germans have a word for it. Rachel Dixon, theguardian.com April 2024

Neuroscience is not another psychological model

Many people seem to think neuroscience is another model of the human mind and psyche to compete with all the psychological ones (as if we needed more!). It isn’t. It’s a body of knowledge about the nervous system that all psychological models can be checked out against. If you were to construct a theory of the human mind purely from neuroscience, you could go in any number of directions. For example, do you tread a primarily cognitive path or a primarily affective one? Neuroscience is actually very malleable – you could probably spin it to back up anything you believe about human psychology. Perhaps fresh psychological models and theories that grow out of neuroscientific soil will emerge in time. This would be interesting – but will they agree with each other? April 2024

The right hemisphere likes paradoxes

I saw a wonderful stage show at the London Barbican that’s based on a Japanese animation, ‘My Neighbour Totoro’. Two children and their father move out of the city to live in the countryside while their mother is laid up in hospital. They discover a magical world in the nearby forest. When they get worried for their mother, they venture into the forest and are helped by a large flying creature - the largest stage puppet I’ve ever seen - to go and see her. All is well. On their return, the father hears their story and tells them “it was a dream, but it wasn’t only a dream”. What a nice paradoxical statement to reconcile a child’s imagination with their lived experience! We need our right hemisphere to understand paradoxes - which it does effortlessly, and which is perhaps why people love this kind of theatre. The show was a sell-out and will return - highly recommended! March 2024

Climate change and our brains

‘Climatological neuroepidemiology’ is something of a mouthful, but it simply means that climate change may be affecting our brains. A forthcoming book by Clayton Page Aldern titled ‘The Weight of Nature: How a Changing Climate Changes our Brains’ goes into this alarming topic. The key point seems to be that there’s evidence for increasing atmospheric CO2 levels impairing people’s decision making, learning, and problem-solving abilities. Added to which are the effects of extreme heat, for example, people tend to be more aggressive and to perform worse on cognitive tests. Heat appears to affect the functional connections between brain areas and therefore their coordination, and to suppress serotonin function, which would link with the aggression. All this sounds bad enough but, even worse, might we be in a negative spiral whereby more CO2 and hotter temperatures are imperceptibly reducing our ability to mitigate climate change? March 2024

Is war a collective psychosis or a case of extreme left hemisphere bias?

Jung thought that the two world wars he lived through were outbreaks of collective psychosis in Europe. I wonder if this is a good description: in psychosis, chaos erupts in the brain in the form of too much firing at too many of the wrong synapses. Whilst chaos is certainly a feature of war, the execution of war is often carefully orchestrated and well organised - unfortunately. And while the orchestrators of war may have lost their senses, the bulk of the population, the collective, may have retained their’s but be unable to do anything about it. Maybe war reflects an extreme triumph of the left hemisphere over the right, manifesting in anger, the drive for power and control, defensiveness, regard for self but not for other, a narrow focus of attention and a failure to see the bigger picture where possibilities for peaceful co-existence would arise - narrow-minded and probably stupid, but not psychotic. February 2024

Did alcohol help create civilisation by switching off the prefrontal cortex?

The fermentation of beer 13,000 years ago enabled our distant ancestors to switch off the self-interested focus of the prefrontal cortex, and humans have been switching it off with alcohol ever since. So says Edward Slingerland, author of Drunk: How we sipped, danced and stumbled our way to civilisation. ‘Switching off the prefrontal cortex’ means less frontal lobe inhibition of the rest of the brain, leading to more relaxed social interaction and the building of communities, trust, and the generation of good ideas. I don’t know whether this is good neuroscience, but I like it! Slingerland even thinks that agriculture developed to make more alcohol, rather than alcohol developed as a by-product of agriculture. Andrew Anthony, theguardian.com January 2024

Healthy brain development requires play

Our discussion group is reading Jaak Panksepp’s Archaeology of Mind on the nature of human emotions. This month we looked at the PLAY system, one of seven core emotional systems in mammalian brains according to Panksepp (the capitals indicate his special use of the word). Is play an emotion? you might wonder. Yes, because it’s the urge to play, involving action and behaviour that accompany the feeling, and it’s the system that underlies joy, whether in children playing happily together or in adults letting go to music, drama, humour and much else that’s enjoyable in life. All young mammals play when they are safe and secure and fed, children included. Given half the chance, they invent games, and a touch of adult supervision is sometimes needed. This contributes to brain development, especially the ‘social brain’, as children learn what’s OK and what isn’t if others are going to want to play with them. Panksepp concludes that “a play-deprived child probably has a higher than normal probability of not only being diagnosed with ADHD but also of becoming reclusive and a potential menace to society as an adult”. Hmm… tempting to speculate about the childhood play experience of some of our political and business leaders! January 2024

Children learn the rhythm and music of language before specific sounds

Mother and baby create ‘lyrical duets’ in their ‘proto-conversations’, in the words of Colwyn Trevarthen, a professor of child psychobiology at Edinburgh. And a new study from Cambridge shows that the rhythms of ‘singsong speech’ and nursery rhymes are crucial for infants to learn language. The old view was that infants learn elements of sound and put them together to make words – phonetics – but this study says they first need rhythm, and the rise and fall of tone, as a scaffold before they can process phonetic information. When they listen to speech, rhythm enables them to spot where one word ends and another begins. This fits with the development of the hemispheres: the right develops faster than the left after birth, the left faster from around 18 months. Music is biased to the right, most language functions to the left. And in evolutionary terms, music preceded language. Well, well, another piece of research that confirms what many mothers have probably intuited for a long time! The Cambridge researchers think that dyslexia and language development disorder may have something to do with the child’s perception of rhythm. theguardian.com December 2023

Chinstrap penguins get by on four second microsleeps

We think of sleep as requiring a decent uninterrupted stretch of time, but nature is extraordinarily flexible in how it organises sleep in different creatures. African bush elephants get by on an average of just two hours sleep a day, which they manage to do standing up. Giant frigatebirds can sleep for just one hour a day while flying across the oceans, which allows them to navigate and hunt on their journeys - but they catch up with 13 hours a day of sleep when back in their nests. However, chinstrap penguins do something really remarkable: they sleep for a mere four seconds at a time, making up for this short duration by nodding off more than 10,000 times a day in microsleeps. So say sleep researchers who studied them in Antarctica with the help of EEG monitoring of their brain waves and video footage of their eyes opening and closing. The super-interrupted sleep pattern allows them to keep an eye on their eggs and their chicks - life must be dangerous! Phoebe Weston, theguardian.com November 2023

Human conflict and oxytocin

Oxytocin is often described as the ‘love hormone’ that promotes bonding between people. But read the serious science about it and it may have a darker side. Robert Sapolsky says oxytocin facilitates mother-infant bond formation and monogamous pair-bonding, and makes people more cooperative and generous – and then goes on to warn that “this comes with a huge caveat – these hormones [he includes vasopressin in the discussion] increase prosociality only toward an Us. When dealing with Thems, they make us more ethnocentric and xenophobic. Oxytocin is not a universal love hormone. It’s a parochial one” (Behave, page 117). We can check this out against our personal experience of bonding which might confirm what he says – such as bonding with others in a team that wants to beat the other team. Speculating… might oxytocin sometimes be a fuel on the fire of human conflict, the urge to protect your own against a threatening other? November 2023

Human conflict and the emotional systems

Another perspective on the current violence in the Middle East comes from Jaak Panksepp’s account of the seven core emotional systems, centred in the brainstem, that are our evolutionary inheritance. The first three are found in reptiles as well as mammals: FEAR, triggered when we’re threatened; RAGE, triggered when something is taken from us against our will; and SEEKING, the motivation to do something in response to FEAR and RAGE (and many other things), including fight or flight behaviours such as seeking revenge or seeking safety (Panksepp used capital letters to denote the special usage of these terms). Evidence of these systems being enacted are in abundance as I write this. To resolve conflict and end wars, the other four systems, found amongst all mammals, are needed: CARE, the urge to look after others; GRIEF when we lose someone we love; LUST which organises sexual behaviour and which sometimes helps to build bridges between different cultures and ethnicities; and PLAY which appears to be an important part of peace negotiations, enabling people to laugh at a joke together when things gets tense. October 2023

Human conflict and the hemispheres

With a terrible new round of violence in the Middle East dominating the news, a reminder of some hemispheric differences relevant to conflict… First of all, anger, taking sides and having to be right are biased to the left hemisphere. Signs of leaning too much on this hemisphere include justifying, rationalising, fruitless arguing, advancing simplistic solutions, as well as defensiveness, avoidance and denial. Grief, fear, emotional overwhelm, and acting out, on the other hand, are biased to the right hemisphere. Leaning into this hemisphere means sometimes feeling uncomfortable and encountering our own vulnerability and unresolved trauma, but it also allows us to tolerate mixed feelings and not-knowing (what we think should be done, for example), have a felt sense of the bigger picture, listen to others, empathise and feel a connection with them, think imaginatively, and seek common ground amidst our differences. Starting from a right hemisphere place, the left can help us to sift through our responses so that we can then focus our attention on the promising ones that might help us to take steps forward in a constructive way. October 2023

Transgender: where the sex of body and brain don’t match

British prime minister Rishi Sunak, in his speech to his party’s annual conference this week, showed his ignorance when he said “we shouldn’t get bullied into believing that people can be any sex they want to be. They can’t – a man is a man and a woman is a woman. That’s just common sense.” Actually, no, Rishi: as with some other issues you have to deal with, it’s not that simple. In the womb, babies develop a sexual body and a sexual brain that don’t necessarily match, thanks to nature’s tendency to vary its basic patterns. The result is that some people are stuck with the body of a different sex from the one they feel themselves to be, meaning real discomfort and a wish to end the mismatch. This neurobiological phenomenon no doubt manifests on a spectrum of severity and may not explain everything about gender dysphoria, but it’s likely to be at the root of much transsexual and transgender experience. A little neuroscience can dispel common misunderstandings about being human, and stop prejudice in its tracks. October 2023 (I will expand this into a long note soon)

Feelings and facts: how conspiracy theories engage both hemispheres

Another hemispheric perspective on conspiracy theories to add to Iain McGilchrist’s point about the left hemisphere favouring consistency over truth (below). Naomi Klein in her latest book Doppelganger writes: “Conspiracy theorists get the facts wrong but often get the feelings right. The feeling that every human misery is someone else’s profit… the feeling that important truths are being hidden.” A hypothesis: a perfectly normal feeling of suspicion starts in the right hemisphere, links with some apparent facts as the left hemisphere delves into the details, and then forms an unholy constellation anchored in the desire for a quick explanation that seems coherent and consistent, rather than in a continuing open-minded enquiry that would require returning afresh to the right hemisphere (McGilchrist’s right-left-right movement). Add to this the understandable feelings of fear that our world engenders – of climate change for example – and a defensive left hemisphere-biased take on things is maybe not so surprising. October 2023

Jellyfish with no brain but just a few neurons can learn to avoid obstacles

We have a nervous system so we can learn, and that means having a brain, does it not? Well, no, actually. Jellyfish don’t have brains, but they do have clusters of neurons linked to whatever it is they see with (‘rhopalia’ apparently, which aren’t exactly eyes), and these clusters are sufficient to enable them to learn to keep out of harm’s way. So: researchers put ‘box’ jellyfish into a variety of tanks, One tank was decorated with black and white stripes to mimic mangrove roots that the jellyfish must avoid if they are to keep their, er, jelly intact. Another had grey and white stripes, and a third was plain grey with no stripes. The jellyfish in the black and white stripe tank never bumped into the tank walls, those in the tank with plain walls frequently bumped into them, and – the interesting bit – those in the grey striped tank initially bashed into the walls but then learnt to avoid them (most of the time). The researchers concluded that a neuron cluster is all that’s needed to learn from experience, and speculated that maybe single neurons can learn (this goes against all the neuroscience books that attribute learning to synaptic changes between neurons). Good news for jellyfish, at least. And which is more remarkable – that just a few neurons can learn to avoid obstacles, or that neuroscientists can dream up such exotic research experiments? I hope they put the jellyfish back in the sea afterwards. Guardian website September 2023

Owls can see what they hear

Owls appear to have their own kind of neurodiversity: they process sound in the visual centre of their brains. While most creatures, including us, process sound with the auditory cortex in our temporal lobes (near to the ears), and do vision at the back of our brains (furthest from the eyes, so no consistency of layout here) in our occipital lobes, owls apparently deal with both in their occipital lobes. Owls are well known to have super-sensitive hearing enabling them, for instance, to catch voles in winter snoozing under a blanket of snow, so they may ‘see’ what they’re hearing. Of course, owl eyes and ears are arranged differently from other birds - whether this has anything to do with their neural arrangements I have no idea. (from What an Owl Knows by Jennifer Ackerman, reviewed in the Guardian June 2023)

Why look ‘beyond the brain’?

Some people seem to want to go ‘beyond the brain’, as if their brains limit their experience and they need to venture into the ethers outside their heads. Yet the human brain is, in the words of neurosurgeon Henry Marsh, “a mystery… as great as the stars at night and the universe around us”, and every neuroscientist wants to understand it better. Why look elsewhere if we have a way to go to get our heads around the wonderful thing inside them?

I suspect the beyond-the-brain fad reflects our cultural bias towards the left hemisphere, a tendency to equate the brain with just the left half of it that is more in the centre of our awareness and more verbal. The left hemisphere cannot see what it doesn’t see – to see it, it needs to enlist the help of the right hemisphere with its broader perspective that lies more at the edge of our awareness. Furthermore, we try to understand the right hemisphere with our left, which isn’t possible: we need our inner experience to understand the right. So our biased left hemispheres may ignore the right and look to supposed phenomena beyond our biology. Maybe such phenomena exist, but simpler explanations lie closer to home in our heads, and these are surely the place to start in understanding ourselves. Read Iain McGilchrist!

Daytime napping stops your brain from shrinking

A link between habitual daytime napping and brain volume has been reported by researchers at University College London and a university in Uruguay. Larger total brain volume is good for brain health as we age and for avoiding dementia, while brain shrinkage is accelerated in ageing people with cognitive problems and neurodegenerative conditions. There are caveats: the link was found in people with genetic predispositions to daytime napping (I must have a few of those), begging the question whether it applies to those without, and all the people studied were white and British. Anyway, I will enjoy my siesta after lunch all the more, remembering to keep it short, of course. June 2023

The left hemisphere favours consistency over truth

Why is the world awash with misinformation, conspiracy theories and crazy ideas that can be easily demolished? Iain McGilchrist offers a hemispheric take on this in his latest book The Matter with Things. He says the left hemisphere wants to be consistent to a simple position, and it’s more important that we appear not to contradict ourselves than that we lie. “The preference for consistency over truth is itself characteristic of the left hemisphere” (page 33). So we may come to believe something which at a deeper level we know is not true. The left hemisphere’s view is simplistic - black and white, ‘either/or’ - and easy to articulate. Whereas the right hemisphere sees the nuances, and the need to embrace different truths that may seem incompatible - ‘both/and’ ~ and this view is harder to articulate. It’s obvious which way those who want to dominate a conversation will go.

When people use their right hemisphere as well as their left, they listen, think about what others say, are open to changing their mind or admitting they’re unsure or don’t know. Instead of reacting with what they usually say, insisting, and probably raising their voice as they do so.

Deep sleep is like a dishwasher deep clean cycle

An interesting piece by Linda Geddes on how sleep washes toxic waste out of the brain. As blood flows in and out of the brain during the deep part of the sleep cycle, cerebrospinal fluid moves through tiny channels surrounding blood vessels and washes out molecular detritus. This happens in waves that wash over the brain every 20 seconds or so, and that stop when we wake up. The channels are similar to the body’s lymphatic network but are managed by the brain’s glia cells, and they get less efficient as we get older. Neurons active during the day produce ‘waste’ that includes beta-amyloid, a toxic protein that accumulates in Alzheimer’s brains, tau protein that accumulates in Parkinson’s brains, lactic acid that’s linked to seizures, and inflammatory molecules produced by immune cells - so here is part of the unfolding story of inflammation and the brain. In the body, deep sleep is good for releasing growth hormone that helps to repair muscles, bones and immune cells, and for regulating blood glucose levels. (Guardian website, March 2023)

Ayahuasca makes the brain anarchic

Psychedelic news from Imperial College London: brain scans of volunteers taking ayahuasca showed signalling between frontal lobe areas involved in planning, language, memory, decision-making and imagination becoming more fluid and anarchic. The active ingredient in the ayahuasca plant is dimethyltryptamine (DMT) which disrupts the inhibitory rhythms between neural networks so they become ‘hyper-connected’. Older neural systems are disinhibited (as happens when we dream) and more evolved functions such as imagination run wild. The volunteers reported hallucinations, near death experiences, ‘higher-dimensional’ beings, and alternative realities that felt life-transforming (sometimes followed by unpleasant gut disturbances, so the experience was not completely wonderful). Ayahuasca combines well with therapy for depression as DMT is short-acting and therefore flexible to use, whereas psilocybin and LSD have effects that last for many hours. (reported on the Guardian website, March 2023)

Alcohol and anxiety

A good explanation of how alcohol makes you less anxious at first but then more anxious later comes from David Nutt, professor of neuropsychopharmacology at Imperial College and one-time UK drug czar fired for telling the truth about drugs. Alcohol stimulates GABA, the inhibitory neurotransmitter, which reduces neural firing and calms the brain, making you less anxious and more relaxed. After a few drinks, the alcohol also blocks the release of glutamate, the excitatory neurotransmitter, making you even less anxious. But all is not well. The body tries to redress the imbalance of brain chemistry by reducing GABA and raising glutamate levels, so when you stop drinking, you’re in a low GABA / high glutamate state – which leaves you anxious and tempted to remedy your hangover by drinking again. And there’s also noradrenaline which suppresses the stress response when you start drinking but which then triggers it when you stop drinking - hence, high anxiety. Finally: glutamate is needed to lay down memories, and the blocking effect of too much alcohol (before the body intervenes) means that we may not remember what happened the night before. (Brain and Mind Made Simple by David Nutt)

Artificial intelligence vs. human intelligence

Eugeny Morozov, who writes about technology and politics, says AI is neither artificial nor intelligent. It’s not artificial because it draws on the work of real people – artists, musicians, writers and so forth. And it’s not intelligent because its strength lies in pattern-matching, whereas human intelligence can also make generalisations. “When we generalise, emotion overrides the entrenched and seemingly ‘rational’ classifications of ideas and everyday objects. It suspends the usual, nearly machinic operations of pattern-matching,” says Morozov. He draws on Ignacio Matte Blanco, a Chilean psychoanalyst who said that human intelligence rests on ‘bi-logic’: “a fusion of the static and timeless logic of formal reasoning and the contextual and highly dynamic logic of emotion.” Stemming from the fusion of both left and right hemispheres, presumably - while AI seems to be a sophisticated kind of left brain affair. (Guardian website, March 2023)

How ministerial left hemispheres wrecked the economy

Let’s fly a kite… it was reported that Kwasi Kwarteng (briefly Chancellor of the Exchequer if you recall) admitted, after their fall from grace, that he and Liz Truss “got carried away” when they inflicted their mini-budget on the rest of us. The pound crashed, pension funds were close to collapse, mortgage costs rocketed, and the cost of government borrowing went up. Kwarteng said they had lost perspective and disregarded the likely consequences. There was “no tactical subtlety whatsoever”. Truss was described as “over-caffeinated” and wanted everything done immediately, imagining herself to be “invincible, almost regal”. It’s not hard to sense unhinged left hemispheres here, ignoring their counterpart right hemispheres that might have slowed them down, curbed their excessive optimism, provided the humility to listen to wise voices, and given them self-awareness to counter the dopamine-fuelled attractions of being in power. (Harry Taylor in the Guardian, December 2022)

Why thinking too much is mentally exhausting

Prolonged mental activity leads to too much glutamate (the excitatory neurotransmitter) building up in the prefrontal cortex, so the brain tries to slow down to manage the excess and we then feel mentally tired - so say researchers into what our minds are up to. When we concentrate and think hard, the prefrontal cortex has to resist temptation and suppress urges to do something less demanding, which requires glutamate-fuelled effort. The build up of excess glutamate then needs clearing out, and the brain does this by going to sleep. The researchers failed to find a correlation between glutamate levels and self-reported fatigue, but put this down to fatigue awareness being very subjective. (Sascha Pare in the Guardian, August 2022)