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of neural activity that occurred in the initial experience. This replaying in the brain
would be accompanied by remembering in the mind. . . . The neurobiological level of
memory is illustrated by a study of synaptic structure and synaptic action under con-
ditions either of enhanced activity or of disuse. In this way it is shown that there are
modifiable synapses that could be responsible for memory because they are greatly en-
hanced by activity and depleted by disuse. . .13
In terms of the actual neurological processes involved, Eccles concludes on the basis
of experiments that there is good evidence that the spine synapses on the dendrites of
54 YOGA AND PSYCHOLOGY
neurons in the cerebral cortex and the hippocampus are modifiable to a high degree
and exhibit a prolonged potentiation that could be the physiological expression of the
memory process.14 It is suggested that increased potentiation could result from either
growth (hypertrophy) of the dendritic spine synapses or branching of the spines to
form secondary spine synapses. By contrast, disuse is seen to result in a regression and
depletion of spine synapses (Figure 1). That this psychobiological approach to mem-
ory is still very current and can be seen in a recent article by Francis Crick and Christof
Koch.15 Their focus is still on possible memory mechanisms located at the synapse, al-
though the thinking as to what may be happening is somewhat more sophisticated
regarding short- and long-term memory. Yet, the Freud-Eccles-Pribram approach dis-
cussed here is still a viable possibility.
The above theorizing by Freud and experimentation by Eccles may well serve as
.
the modern explanation of the physiological character of karmic samsk

ras and
v

san

s, an explanation which in Patañjali s time involved a long and detailed discus-
sion as to how the gunas, or constituents of consciousness (sattva, rajas, and tamas),
.
function in the various karmic states.17 In ancient Yoga terminology, the structuring
of a memory trace was described as an accumulation of a latent deposit of karma,
which would have as its neural basis a significant tamas, or physical structure compo-
nent, perhaps parallel to enlarged dendritic spines of modern physiology. The Yogic
notion of habit patterns, or v

san

s, as resulting from repetitions of a particular mem-
.
ory trace, or samsk

ra, fits well with the modern idea of growth at the synaptic spines.
.
The Yoga notion that the repetition of a particular samsk

ra results in a habit pat-
tern, or v

san

, assumes that memory and motivation are two aspects of the same psy-
chological process. Freud, too, called attention to the intimate linkage of motive and
memory. Motivation in Freud s view is selection, and selection is to a large degree the
result of memory traces of prior experience.18 Freud s analysis of the neurophysiolog-
ical process required is as follows. Every neuron must be presumed to have several
paths of connections with other neurons. Consequently, the possibility exists for
choice among various neural pathways. But, as the Yoga theory of karma points out,
people do not behave as if all paths are equally likely. Therefore, particular motiva-
tional patterns must be provided for in the functioning of the neural network. Freud
Figure 1. The drawings are designed to convey the changes in spine synapses that are
postulated to occur with growth in B and C and with regression in D.16
FREUD, JUNG, AND YOGA ON MEMORY 55
accomplished this in terms of  cathexis, or the buildup, through repetition, of neural
energy at a particular synaptic spine, which leads to transmitted excitation only under
the conditions appropriate to that neural network. Thus, on the same neuron there
could exist several synaptic spines each connected to different neural networks.
Choice occurs when, as the impulse reaches the neuron, one of the several possible
neural networks is selected. In Freud s view, the selection procedure prevents purely
random transmission and operates on the basis of the cathexis, or potential energy
buildup, at each synaptic spine.19 This would be the neurophysiological correlate for
the motivational, or karmic, predisposition in psychic functioning.
As Pribram makes clear, Freud in his  Project did not succeed in solving  the ques-
tion of how neural impulses are directed through a net, and under what conditions such
selective direction leads to an adapted repetition of the neuronal pattern. 20 But in pos-
ing this important problem, says Pribram, Freud was far ahead of his time. Only re-
cently has neurophysiology attained the laboratory techniques to study simultaneously
what goes on in different portions of a neuron. In theory, both Yoga and Freud agree
that memory and motivation are parts of a single psychic process which also embodies
choice or selection. It would seem that only now has the science of neurophysiology ad-
vanced to the point where this theory can be empirically tested. Perhaps the experi-
mental evidence, when obtained, will help to clarify the paradox which still remains,
namely, to what degree is this choice or selection process free or determined?
In addition to his  Scientific Project, which he seems to have given up around
1895, Freud dealt with memory and motivation in the development of his theory of
psychoanalysis. There, Freud argues that when our sense organs are stimulated, men-
tal pictures are created of the perceived objects and preserved as memory traces in the
unconscious.21 These memory traces become associated with motivation when the
personality becomes engaged in the process of tension reduction, as, for example,
when a baby becomes hungry, triggering memories of the sight, smell, taste, and feel
of food. This process, which produces a memory image of an object that is needed to
reduce a tension, Freud called a primary process.22 When such processes are perceived [ Pobierz całość w formacie PDF ]