Later On

A blog written for those whose interests more or less match mine.

Archive for October 3rd, 2022

Seeing and somethingness

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Nicholas Humphrey, emeritus professor of psychology at the London School of Economics and author of many books on the evolution of human intelligence and consciousness, the latest being Sentience: The Invention of Consciousness, writes in Aeon:

The cover of New Scientist magazine 50 years ago showed a picture of a rhesus monkey, with the headline ‘A Blind Monkey That Sees Everything’. The monkey, named Helen, was part of a study into the neuropsychology of vision, led by Lawrence (Larry) Weiskrantz in the psychology laboratory at the University of Cambridge. In 1965, he had surgically removed the primary visual cortex at the back of Helen’s brain. Following the operation, Helen appeared to be quite blind. When, as a PhD student, I met her a year later, it seemed nothing had changed.

But something puzzled me. In mammals, there are two main pathways from the eye to the brain: an evolutionarily ancient one – the descendant of the visual system used by fish, frogs and reptiles – that goes to the optic tectum in the mid-brain, and a newer one that goes up to the cortex. In Helen, the older visual system was still intact. If a frog can see using the optic tectum, why not Helen?

While Weiskrantz was away at a conference, I took the chance to investigate further. I sat with Helen and played with her, offering her treats for any attempt to engage with me by sight. To my delight, she began to respond. Within a few hours, I had her reaching out to take pieces of apple from my hand; within a week, she was reaching out to touch a small flashing light… Seven years later (as shown in the video below), she was running round a complex arena, deftly avoiding obstacles, picking up peanuts from the floor.

To anyone who’d observed Helen in 1972 – and didn’t know the history – it would have seemed that her eyesight was now quite normal. Yet, could she really ‘see everything’, as the New Scientist’s cover implied? I didn’t think so. I found it hard to put my finger on what was missing. But my hunch was that Helen herself still doubted she could see. She seemed strangely unsure of herself. If she was upset or frightened, her confidence would desert her, and she would stumble about as if in the dark again. The title I gave to my article inside the covers of the magazine was ‘Seeing and Nothingness’.

We were on the brink of a remarkable discovery. Following on from the findings with Helen, Weiskrantz took a new approach with a human patient, known by the initials DB, who, after surgery to remove a growth affecting the visual cortex on the left side of his brain, was blind across the right-half field of vision. In the blind area, DB himself maintained that he had no visual awareness. Nonetheless, Weiskrantz asked him to guess the location and shape of an object that lay in this area. To everyone’s surprise, he consistently guessed correctly. To DB himself, his success in guessing seemed quite unreasonable. So far as he was concerned, he wasn’t the source of his perceptual judgments, his sight had nothing to do with him. Weiskrantz named this capacity ‘blindsight’: visual perception in the absence of any felt visual sensations.

Blindsight is now a well-established clinical phenomenon. [And this perhaps explains why Ved Mehta, though blind, was able to run around easily at the school for the blind he attended in Arkansas, as he describes in his (fascinating) autobiography Face to Face. I always wondered about that. – LG]  When first discovered, it seemed theoretically shocking. No one had expected there could possibly be any such dissociation between perception and sensation. Yet, as I ruminated on the implications of it for understanding consciousness, I found myself doing a double-take. Perhaps the real puzzle is not so much the absence of sensation in blindsight as its presence in normal sight? If blindsight is seeing and nothingness, normal sight is seeing and somethingness. And surely it’s this something that stands in need of explanation.

Why do visual sensations, as experienced in normal vision, have the mysterious feel they do? Why is there any such thing as what philosophers call ‘phenomenal experience’ or qualia – our subjective, personal sense of interacting with stimuli arriving via our sense organs? Not only in the case of vision, but across all sense modalities: the redness of red; the saltiness of salt; the paininess of pain – what does this extra dimension of experience amount to? What’s it for? And, crucially, which animals besides ourselves experience it, which are sentient?

Sensation, let’s be clear, has a different function from perception. Both are forms of mental representation: ideas generated by the brain. But they represent – they are about – very different kinds of things. Perception – which is still partly intact in blindsight – is about ‘what’s happening out there in the external world’: the apple is red; the rock is hard; the bird is singing. By contrast, sensation is more personal, it’s about ‘what’s happening to me and how I as a subject evaluate it’: the pain is in my toe and horrible; the sweet taste is on my tongue and sickly; the red light is before my eyes and stirs me up.

It’s as if, in having sensations, we’re both registering the objective fact of stimulation and expressing our personal bodily opinion about it. But where do those extra qualitative dimensions come from? What can make the subjective present created by sensations seem so rich and deep, as if we’re living in thick time? What can the artist Wassily Kandinsky mean when he writes: ‘Colour is a power which directly influences the soul. Colour is the keyboard, the eyes are the hammers, the soul is the piano with many strings’? Why indeed do people use the strange expression ‘it’s like something to’ experience sensations? Is it because conscious sensations are like something they cannot really be? . . .

Continue reading. There’s quite a bit more.

Written by Leisureguy

3 October 2022 at 12:16 pm

Gift links not so good as I thought

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I just learned that gift links expire after two weeks. I thought they were permanent. Now I find my posts are sprinkled with links that work only for subscribers. Rats.

Written by Leisureguy

3 October 2022 at 11:30 am

Posted in Business, Daily life, Media

To prevent gun injury, build better research

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Republicans are opposed to research in general — “What good is science if it tells us things we don’t want to hear?” they ask (cf. climate change, economics of US history, etc.) — and that is why research into gun violence was not funded by Congress: Republicans blocked it. Chethan Sathya writes in Nature:

From 2001 to 2020, US cancer death rates fell by 27%. The nation’s traffic fatality rates per 100,000 people fell by about 21%, even counting a small rise in 2020. By contrast, US gun death rates went up: by 24% for suicide and by 48% for homicide1 (see ‘Deaths up’). In 2020, firearms became the leading cause of death for US children2. Yet firearm injury is among the least researched and worst funded of the leading causes of death in the United States3,4 (see ‘Dollars by death rate’).

We are clinicians, researchers and advocates who are convinced that more research on the topic can help to reduce deaths and injuries. It has helped in other fields. For instance, seatbelts in cars were initially considered an industry issue, but a public-health framing brought more data and encouraged effective safety measures. Better data and improved research have similarly informed comprehensive public-health strategies that have reduced issues from tobacco use and child drownings to lead poisoning and vaccine-preventable diseases. Providing evidence can inform strategies that both tackle the root causes of a problem and use timely, accurate data to iterate solutions. It will take more than data to reduce harm, but firm evidence and improved understanding can spur effective efforts.

According to a 2017 review, the volume of research publications related to firearm injury was only 4.5% of that predicted based on health burden4. A 2019 paper5 estimated that a 30-fold increase would be needed in funding for paediatric firearm-injury prevention alone to achieve funding levels on a par with other causes that have similar mortality rates. Despite recent improvements, the number of researchers in firearm-injury prevention remains low. . .

Continue reading.

Written by Leisureguy

3 October 2022 at 11:26 am

Strong ‘n Scottish ‘n the wonderful iKon slant

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My Omega Pro 48 is always a pleasure, and today it worked up a superb lather from Meißner Tremonia’s Strong ‘n Scottish shaving soap “with scotch whisky and sheep wool fat.” 

iKon’s wonderful stainless slant (not the cast-aluminum X3) now comes with a B1 coating. (Mine is from pre-coated times.) It did a superb job, as it always does. With this slant — as with most, in fact — the key is to ride the edge of the cap, which puts the handle rather far from the face. 

Three passes removed every trace of my two-day stubble, and then a splash the world’s oldest aftershave, Pinaud Lilac Vegetal, combined with a couple of squirts of Grooming Dept Hydrating Gel, finished the job. 

The week begins on a fine note.

The tea this morning is Murchie’s Baker Street Blend: “Lapsang Souchong, smooth Keemun, rich Ceylon, Gunpowder, and floral Jasmine.”

Written by Leisureguy

3 October 2022 at 8:03 am

Posted in Caffeine, Shaving

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