![]() And surely it’s this something that stands in need of explanation. 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. ![]() Yet, as I ruminated on the implications of it for understanding consciousness, I found myself doing a double-take. No one had expected there could possibly be any such dissociation between perception and sensation. When first discovered, it seemed theoretically shocking. Weiskrantz named this capacity ‘blindsight’: visual perception in the absence of any felt visual sensations.īlindsight is now a well-established clinical phenomenon. So far as he was concerned, he wasn’t the source of his perceptual judgments, his sight had nothing to do with him. To DB himself, his success in guessing seemed quite unreasonable. To everyone’s surprise, he consistently guessed correctly. Nonetheless, Weiskrantz asked him to guess the location and shape of an object that lay in this area. In the blind area, DB himself maintained that he had no visual awareness. 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. We were on the brink of a remarkable discovery. The title I gave to my article inside the covers of the magazine was ‘Seeing and Nothingness’. If she was upset or frightened, her confidence would desert her, and she would stumble about as if in the dark again. ![]() But my hunch was that Helen herself still doubted she could see. I found it hard to put my finger on what was missing. Yet, could she really ‘see everything’, as the New Scientist’s cover implied? I didn’t think so. 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. 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. I sat with Helen and played with her, offering her treats for any attempt to engage with me by sight. While Weiskrantz was away at a conference, I took the chance to investigate further. If a frog can see using the optic tectum, why not Helen? In Helen, the older visual system was still intact. 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. When, as a PhD student, I met her a year later, it seemed nothing had changed.īut something puzzled me. Following the operation, Helen appeared to be quite blind. In 1965, he had surgically removed the primary visual cortex at the back of Helen’s brain. 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. "Let me say that you guys have an awesome website.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’. "We love your interactive maps and are using them for 10th grade world history." Thanks, Susan McCormick it is the only reason I am passing my World Geography class!" -Stephen Eleanor Terry and the Dixon Middle School Geography Detective Club "I am a middle school social studies teacher who also sponsors a geography club after school. ![]() "Terrific online educational games, especially geography." Sheppard Software's geography games were featured in the Boston Public Library's 2006 Exhibition on Mapping! Candice Gomes, Education Outreach Coordinator, Boston Public Library Since then, your games have become quite a hit with my competitive colleagues!" "I stumbled upon your fun interactive geography games from a link on the Massachusetts Geographic Alliance Website.
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