"The key process of memory is retrieval Top
Endel Tulving in interview with Michael Gazzaniga
"Of course memories are not stored at synapses. But I think it is useful to
contemplate the possibility that they are not stored anywhere else in the brain either.
The whole issue of where or, more important, how memories are stored in the brain may turn
out to be an incorrect formulation of the problem, despite its seductively enticing
allure. And the sournce of such an incorrect formulation may lie in the single-minded
preoccupation with the storage, or the engram, and sometimes even identification of
storage with memory. This preoccupation with the physical changes that follow from an
experience that can be remembered seems to be accompanied by a rather conspicuous neglect
of retrieval processes." (97)
"As a scientist I am compelled to the conclusion—not postulation, not
assumption, but conclusion—that there must exist certain physical-chemical changes in
the nervous tissue that correspond to the storage of information, or to the engram,
changes that constitute the necessary conditions of remembering. (The alternative stance,
that it may be possible for any behavior or any thought to occur independently of physical
changes in the nervous system, as all your good readers know, is sheer mysticism.)
However, if the engram is a kind of entity that manifests itself only in activity, or
retrieval, then we might conjecture that the physical changes resulting from experience do
not exist as an engram in the absence of that activity. And we can also imagine that the
engram, qua engram, is not detectable in its quiescent state, that is, in the absence of
retrieval, with any physical technique." (98-99).
"Even if you could somehow identify the total pattern of physical/chemical
aftereffects of an experienced event, in all of its intricate and elaborate detail and
full-blown complexity, you would nhave no way of knowing or predicting what kind of a
memory (in the sense of experience) that engram is going to produce: that depends on the
retrieval process, and that process has not yet occurred." (104).
"It is not only useful but important to distinguish between the storage metaphor, on
the one hand, and the idea of the physical indeterminacy of the engram, on the
other." (106).
"The approach of cognitive psychology and the approach of neurobiology are
complementary, and there is no problem whatever. The problem arises only if one assumes
that the physical approach is the only one, or the most essential one, or the fundamental
one, that is, the old die-hard reductionist position. Remembering is a completely
emergent, biological-psychological
process of the brain." (108). "