Archives for category: Sight

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Love can come in the most curious forms.

In his latest book ‘Hallucinations’, Oliver Sacks tells a story about his patient, Gertie C., who suffers intense visual hallucinations as a result of Parkinson’s postencephalictic disease – or ‘frozen’ disease (as described in Sacks’ book and film ‘Awakenings’).

Sometimes frightening, sometimes funny, hallucinations are an offshoot of the disease which is thought to be due to a build up of proteins in the parts of your brain that deals with sight and movement.

After some distress at her visualisations, Gertie decides to submit to the oddities her brain conjures, and embrace the experience instead…

In the form of a hallucinatory gentleman caller.

Every night, he arrives faithfully on her doorstep with flowers, presents, love and warm companionship.

Who says love isn’t real?

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Imagine hearing colours, feeling sounds or tasting shapes.

If you look at the letter ‘4’ and see the colour “green” or have a relationship between the sound of a car horn and feel a pain in your right leg, or smell jasmine when you see a triangle, you could be a part of the less than 1% population who experience Synaesthesia.

Synaesthesia is basically a mash up of senses. A synaesthete receives the same sensory information as you or I, but somewhere in their somatosensory cortex (the parts of your brain that receive sensory information from your body parts) and association areas (the part that is involved in complex mental processes eg forming perceptions), they process the information differently and thus they experience an altered perception – or an altered state of consciousness.

Parts of a synaesthete’s brain when looking at a letter register a letter and a colour at once.

Neuroimaging studies using PET and fMRI demonstrate significant differences between the brains of synaesthetes and non-synesthetes. The degree of white matter connectivity (white matter being the fat that coats the grey nerve cells) in the fusiform gyrus correlates with the intensity of the synaesthetic experience. There is some dispute over the functionalities of the fusiform gyrus, but it is generally accepted that it is involved in:

  1. processing color information
  2. face and body recognition (see Fusiform face area)
  3. word recognition
  4. number recognition [questionable: may only be as a result of a global response of any generic recognition tasks, further statistical evidence needed]
  5. within-category identification

Some famous synaesthetes you might know include French poet Baudelaire, Hungarian pianist Franz Liszt and Russian painter Wassily Kandinsky, who was said to hear tones and chords as he painted; for example yellow was the colour of middle-C on a piano or a brassy trumpet blast. For him, the combinations and associations of colours produced vibrational frequencies akin to chords played on a piano.

Famous novelist Vladimir Nobokov wrote that he associated the letter ‘r’ with a senstion of ‘a sooty rag being ripped’, while the letter ‘a’ he associated with weathered wood.

Needless to say, it helps in the creative process!

For more information on the sensory clashes go to http://www.uksynaesthesia.com/.

Thank you to Wikipedia, and ‘Psychology 2’ by Burton, Westen and Kowalski.

As well as exploring many other patient’s stories, Sacks’ own anecdote in his latest novel ‘The Mind’s Eye” (Picador, 2010) candidly talks about his experiences with an ocular melanoma in his right eye. The treatment required cutting the eye muscle to insert a radioactive plate for 72 hours, zapping the malignant cells. When unsuccessful, this is eventually followed by laser treatment which damages the fouvea – the part of your eye which delivers your central vision.

In the following weeks of recovery he experiences is extraordinary explosions of vision, with the brain suddenly spurting blowouts of bright light and colour as it tries to heal its burned, charred parts and reconnect tissues and messages between optical nerves and occipital lobe.

Colour becomes a riddle for him. Holding up a green apple in his peripheral vision, it is green, but when moved in front of his body (and thus it is viewed by the fouvea) it becomes black; same for bluebells in a meadow – with the untreated eye they remained blue but seen with the damaged eye the flowers became green with the grass.

Similarly, the scotoma or black hole in his central vision behaves as if a sci-fi beast, changing its pattern and colour to suit his surrounds; black when he opens his eyes, if looking at a white wall, the shape would suddenly change to white to match it, or to match the pattern when looking at brick walls, or chess boards.

The colour soon returns to the apples, and he experiences a heightened sense of vision whereby he sees images in his memory long after the event; a kind of heightened visual memory.

It’s an incredible cerebral experience told by such an eloquent physician.

Among his many books, Oliver Sacks has also written ‘The Man Who Mistook His Wife For A Hat’, ‘Awakenings’, and ‘Musicophilia’.
www.oliversacks.com

Oliver Sacks’ most recent book ‘The Mind’s Eye’ looks at the curious relationship between your brain and your eyes.

He follows the patient Sue, who was born stereo-blind (that is, without binocular vision which is necessary to construct a sense of depth). Born cross-eyed she had surgery at ages 2 and 7 buy was told there were no corrective exercises that would be done to help her gain a 3D vision of the world. In her 40’s, with the help of a developmental optometrist,  she decided to try corrective exercises anyway and realised her 3D vision was able to be activated, suddenly seeing the steering wheel and doors “popping out” into the world once the binocular cells in her brain were activated to see the world this way. Without exercises however, this ability faded and she lost her 3D vision, demonstrating the incredible elasticity of the brain’s capacities.

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