Geography Reference
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between the summations of large neighbouring regions, so we have the situation of a huge
but controlled information loss (Gregory, 1998).
The visual pathway also splits the right and left sides of the two retinas (information
travelling along the optic nerve) to the different halves of the brain within the visual cortex.
This is vitally important, especially for stereoscopic vision, as the two images of an object
focused on the two retinas will be found right next to each other, within the visual cortex
of the brain. We therefore have two stages of large information processing being carried
out: first at the early parts of the visual system in the intermediary cells and then later
reconstructed in the brain, which is especially useful for considering intra-eye analysis for
stereoscopic processing.
In the visual cortex of the brain a series of further interactions occur to create more
complicated combined signals. These resulting neurons have been termed simple, complex,
hyper-complex and contour-detecting, amongst others. For example, a specific complex
neuron could detect a bar of light at any angle and position but of fixed length and width.
In the 1990s it was postulated that every recognized object may have a specific individual
neuron in the brain (proposing the existence of the famous 'grandmother cell' that would
detect and fire specifically only when you saw your grandmother), but this was demonstrated
numerically to be impossible [although recent work does show the brain has the ability to
trigger familiar scenes with single cell responses (Quian Quiroga
et al
. 2005)], and the brain
has shown itself to be far more malleable and plastic in behaviour. This was summed up by
D. H. Hubel and T. N. Wiesel in their 1981 Nobel Prize acceptance speech:
what happens beyond the primary visual area, and how is the information on
orientation exploited at later stages? Is one to imagine ultimately finding a cell that
responds specifically to some very particular item? (Usually one's grandmother is
selected as the particular item, for reasons that escape us.) Our answer is that we
doubt there is such a cell, but we have no good alternative to offer. To speculate
broadly on how the brain may work is fortunately not the only course open to
navigators. To explore the brain is more fun and seems to be more profitable. [Full
details of their 25 years of collaboration are available in Hubel and Wiesel (2004)]
As we cannot have cells for all types of objects that we see, it is now known that by training and
concentration the human brain can become hyper-sensitive to certain stimuli. This means
that, owing to a life time of training, both in the short term and in the long term, everyone
sees objects differently relating to age, sex, extrachemical stimulus, living conditions and
all previous experiences (Ludel, 1978). Thus what you see in a geographic visualization is
almost certainly not exactly what someone else sees in the same image.
The signal from the eye, which is a fraction of the total raw information, is then combined
with experience and training within your brain to constitute the 'belief engine'. Therefore,
when a person gains insight from a specific visualization, this may not be apparent to all
viewers, and the final requirement that we recommend, is for there always to be a detailed
description, which 'tells a story' alongside the visualization.
11.2.2 Illusions - creating too much information
The human brain's 'belief engine' means that, at times, we do not actually believe the
right thing, and this can be incredibly convincing, even when logic tells us otherwise.
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