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essays and commentary
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Normal people have a rich variety of memories, including memories of sights, sounds, and factual data. Regarding memory, the whole question of memory has been frustrating for those who have sought its presence in physical substance. During much of the 20th century, there was a determined search for memory in physical substance—by many different researchers. However, these researchers were unable to localize memory in any physical substance.
An issue related to memory is the frequently heard claim that neural networks are the mechanism responsible for human intelligence—in spite of their usefulness being limited to pattern recognition. However, and regardless of usefulness, without both a neural-network algorithm and input-data preprocessing—requiring memory and computational ability—neural networks do nothing. Thus, before invoking physical neural networks to explain any part of human intelligence, memory and computational ability must first exist as part of the physical substance of the brain—which does not appear to be the case.
In the latter part of the 20th century, the most common explanation of memory is that it is stored, in effect, by relative differences between individual synapses. Although this explanation has the advantage of not requiring any memory molecules—which have not been found—there must still be a mechanism that records and retrieves memories from this alleged storage medium. This requirement of a storage and retrieval mechanism raises many questions. For example:
How does a sequence of single-bit signals along an axon—interpreting, for example, the sodium-ion wave moving along an axon and into the synapses as a 1, and its absence as a 0—become meaningfully encoded into the synapses at the end of that axon?
If memory is encoded into the synapses, then why is the encoded memory not recalled every time the associated axon transmits a signal; or, conversely, why is a memory not encoded every time the associated axon transmits a signal?
How do differences between a neuron’s synapses become a meaningful sequence of single-bit signals along those neurons whose dendrites adjoin those synapses?
The above questions have no answer. Thus, the explanation that memory is stored by relative differences between individual synapses, pushes the problem of memory elsewhere, making it worse in the process, because synapses—based on their physical structure—are specialized for neurotransmitter release, not memory storage and retrieval.
Alternatively, given bions, the location of memories is among the state information of the bions that occupy the neurons of the brain. In other words, each memory exists as part of the state information of one or more bions.
 The conscious memories of sights, sounds, and factual data, are high-level representations of memory data that have already undergone extensive processing into the forms that awareness receives (see the discussion of awareness in chapter 6).