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To answer this question, we have first to understand the differences between consciousness and memory. Consciousness takes
many forms such as visual, verbal and musical conditions. Human memory can be considered the solidified form of consciousness
in human brain. Memory may be stored in a variety of ways, including protein activation and inactivation within neurons, or
simply cycles of neural activity. Long-term memory is more relevant to brain reconstruction. It appears that long-term memories
are stored by structural changes in neural processes. These changes include the number of branches a neural process makes
and the number and efficacy of synapses (Byrne et al., 1991). Therefore, specific memory may relate to specific structure,
which can be relatively easy to record and download.
If you open a computer, you see circuit boards, integrated
circuits with millions of transistors on them, and various wires connecting parts. Knowing where all the circuits go, where
all the wires originate, how the integrated circuits are laid, what the hard drive and CR ROM look like inside out tells you
absolutely nothing about the information encoded in 1 and 0, plus and minus, on data storage units. One must know exactly
how the data is stored in order to copy it. Similarly, it may take decades for the mechanism of memory and consciousness to
be fully elucidated, and it will, just as the human genome, once thought impossible to fathom, was sequenced. But YOU may
not have the luxury of waiting decades to have your memory and consciousness stored. You may need to act soon. We understand
that. There is much to do, and the sooner we start, more is preserved as it exists today, and presumably the better will be
your reconstruction in the future.
The form that appears to be easiest to study is the visual consciousness, since
humans are very visual animals and our visual percepts are especially vivid and rich in information. The visual system of
primates appears fairly similar to our own (Tootell et al., 1996), and many experiments on vision have already been done on
animals such as the macaque monkey. Psychological evidence suggests that conscious humans are engaged almost continuously
in adaptive processes involving semantic knowledge retrieval, representation in awareness, and directed manipulation of represented
knowledge for organization, problem solving and planning.
Imaging technology provide powerful tools to record human
consciousness and human memory. Two types of imaging technologies are frequently used in diagnosis and functional analysis
of brain abnormality: structural imaging technology and functional neuroimaging technology. Structural imaging technology
includes computed axial tomography (CT) and Magnetic resonance imaging (MRI). Functional neuroimaging technology includes
positron emission tomography (PET), single photon emission computed tomography (SPECT), functional magnetic resonance imaging
(fMRI) and magnetic resonance spectroscopy (MRS).
PET activation studies of working memory (Jonides et al., 1993)
have demonstrated the involvement of the frontal lobe in this aspect of mental functioning. Paulesu, Frith, and Frackowiak
(1993) while employing the PET methodology concluded that the articulatory loop of working memory contains two components
with visual presentations: (1) a phonological store localized to the supramarginal gyrus on the left, and (2) a subvocal rehearsal
system associated with Broca's area on the left. Further more, PET studies in humans have shown a selective bilateral increase
in regional blood flow in the dorsolateral prefrontal cortex associated with working memory tasks (Burbaud et al., 1995).
Stein et al. (1995) found that a spatial working memory task activated middle, inferior, and premotor frontal cortex with
predominant activation on the right side. The memory task also resulted in anterior cingulate and posterior parietal activation
bilaterally.
Quantitative analysis of these data provide measurements of the temporal and spatial distributions
of gadolinium enhancement and of N-acetylasparate, choline, creatine, and lactate/lipid (Nelson et al., 1997) (Preul et al.,
1998). Combining these data allows morphology, metabolism, and function to be studied simultaneously, the complementary nature
of the information from these modalities becoming evident when studying pathologies reflected by metabolic or electrophysiologic
dysfunctions (Bidaut et al., 1996; Bigler, 1999).
Memory can be managed through medication. The study led by Stacy
Castner at Yale School of Medicine has found the working memory loss can be reversed using a short-term drug regimen that
produces long-lasting effects. Long-term treatment with antipsychotic medications for diseases such as schizophrenia, may
decrease the number of D1 receptors, which control memory function, in cortical neurons thus produces memory impairments when
the treatment lasts over several months (Castner et al., 2000).
Artificial stimulus can create percepts and behavior.
For example, stimulation of the carotid body chemoreceptors leads to an enhancement of the response of somatosensory neurons
to their normal physiological input (Angel and Harris, 1998). This suggests that the manmade manageable information, electronic
stimulus in this case and may be in digital form, can evoke behavioral changes. It also suggests that not far from now we
might be able to create other human perceptions based the information collected through modern anatomical and functional imaging
devices.
Today it is easy to understand when we compare the human brain with a computer, and the human mind to a program
running on that computer. How many megabytes, gigabytes, terabytes of memory the human brain have? The remarkable result from
Landauer?ork was that human beings remembered very nearly two bits per second under the experimental conditions such as visual,
verbal, musical conditions. Continued over a lifetime, this rate of memorization would produce somewhat over 109 bits, or
a few hundred megabytes Technological advance in hardware may well exceed the requirement for storage and retrieval capacities
of physical unit in the brain in forms of molecular parts, synaptic junctions, whole cells, or cell-circuits. The advancement
of artificial intelligence may solve the issues of coding and decoding memory, reasoning and decision-making that mimics human
intelligence (Landauer et al, 1986).
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