Cerebral and Extra Cerebral Memory
There are two main types of memory, cerebral and extra cerebral.[AS]
- Cerebral. Mainly current life memories, stored in the brain ( citta) and accessed by the manomaya kosa ( aham). These would be pictures stored in the body and chakras? This is the main component of the memories that make up the unconscious mind?
- Extra cerebral. Contains the memories that survive death, and must therefore be located in the atimanas kosa (or above). These would include the inborn samskaras that are carried over from one life to the next. These are the spirit memories that the psychics say are stored in a placed in back of the head. Are these memories also stored in citta, but at a different level of mind? or do they reside somewhere else?[CAS]
An interesting question is where the samskaras acquired in the current lifetime are stored. Do they reside in both levels of memory? Do they start in one and move to the other? Is there is a parallel system, of memories and samskaras, where the memories are something like specific instances, or expressions of samskaras? Then they could be laid down together, or perhaps as the number of memories ( pictures) accumulated they could form samskaras?
What also is the role of physical memory, which apparently resides in the body? Both the memory that allows the body to perform flawless sports without conscious control, and the memory which is accessed by rebrithing? Perhaps the memory is distributed across various kosas (as the citta may be), so that each memory has a physical component, as well as others at other levels? Then the attention, the ( aham) of perception can access the memory via different channels.
If the memories are stored in the citta, but come to awareness due to the attention of the aham, then is the part of the citta that forms the "screen" for current perception or memory different from that which holds the memories? Or are all the memories etc. viewed in situ? The distinction between manas and citta in the vedantic model indicates such a distinction, that the memories have to "come bubbling into view". Or does this rather indicate the movement of the memory from one kosa to another? I.e. is the function of perception fixed, involving a specific part of the citta which progressively takes on different forms, like a series of movies on the same screen, or does it wander like a search light which can move from one screen to another? In the latter case it might well be able to shift from one kosa to another, to focus on different types of memory. In the former it seems that the images must be transfered, or expressed from one layer to another.
Perhaps it is in fact a combination? In viewing a screen with the eyes, one can only focus on one thing at a time, although there is a general awareness of the whole. However, objects that radiate outside of the visible spectrum can only be seen if their image is in some way converted into a visible frequency. Likewise objects may be off stage entirely and have to be brought into the picture.
There has been a long debate over how and where memories are stored in the brain. While certain types of memory are apparently related to, and dependent on, certain areas of the brain (the various small brains), it is unclear that they are actually stored in any given place. In other words, while specific neurons appear to be involved in the recognition of edges, stripes, or bars, it is not clear that these areas hold actual memories of such features.
It has been suggested that memory is closely linked to the specific mental functions (and in some way to consciousness itself), with each function (e.g. music, images, or words, both heard and spoken) having its own type of memory. [SFF] [This is related to the necessity of memory in order to associate meaning with raw perception and thereby bring it into consciousness].
In people who have certain damage of the brain (or persons with some mental disorders) it appears that specific memory can remain, while general memory, or the ability to recognize something as belonging to a group may be missing. Rosenfield goes as far as to suggest that memory itself is a function of language and categorization. It also appears that these persons are in someway aware that they are having trouble, and often become distraught, both physically and psychologically. It seems that they are not merely missing a memory, but that their consciousness itself has been altered.[SFF]
The strength of memories is related to the biochemistry of the
emotional state at the time of creation. When stress triggers the
secretion of epinephrine and nor-epinephrine
by the adrenals affects the vagus nerve
(heart nerve) sending signals back to the
amygdala, which sends signals to strengthen memories in formation.
In general the level of emotional arousal (positive or negative) will
strengthen the associated memories. Memories can therefore be both
factual and
emotional, and the later may be unconscious when formed via the
amygdala directly.[EI]
There is a possibility of distributed
physical memory. Beyond the way in which the body learns and remembers
various actions, some paralysis patients have found that they loose all
memory of their paralyzed limbs. [SFF]
Some physical memory, e.g. playing the guitar or using a keyboard to
type, are referred to as procedural memory. [AM]
This is the memory of spacial relationships including geometry. [AM]
This type of memory continues to exist even in people who are otherwise
amnesic. They are able to become familiar with places and people that they
come into repeated contact with. Even facts that are repeated over and over
may be memorized. However there is no sense of context, no memory of where
or when the person, fact, or place was previously encountered. It is a
sort of subconscious memory . Unlike
explicit learning, implicit learning seems to use older portions of the
brain, and possibly more diffuse paths. It seems similar to the processes
that form habits. It is not dependent
on the full multistage processes involved in forming
long term memories.[AM]
The change in remembrance of events anti-dating blindness suggests
that it is the current self-image that
is involved in the memory process, rather than that existing when the
memory was laid down. The act of remembering combines the original
experience with the current self-image. Various changes in the self-image
are reflected in the ability to remember related events and objects. It
is not the memory itself that has been erased of affected, but the
function of bringing it into consciousness. With the loss of sight,
the visual body image fades, and with it the visual memory. [SFF]
Persons and places not experienced since an accident remain
fresh, with visual images intact. But those that are experienced
after the blindness fade and are altered by the new modalities of
the experience. [SFF]
Persons who loose the perception of color, also loose color in
their dreams and memories. Initially the abstract knowledge of
color remains, but eventually that also fades. After five years
even the colors of common objects may be forgotten. [AM]
It can happen that a person while not blind loses the ability to
recall things visually, or even to recognize familiar places and
persons. It is suggested that this is the result of loosing access
to one's body image, which inhibits
the formation of visual memory. That is the entire process of
recognizing or recalling visual images (which had been very strong)
brakes down, however verbal memory was not impaired, and came forward
to take the place of the previous visual memory. This person also
reported a lessening of pleasure
and pain, similar to the lessening
of emotions in persons who lose consciousness of parts of
their bodies. This follows from the self-referential nature of basic emotions, which are only experienced
due to the harmonization (or lack) of sensory vibrations with those
of one's samskaras.
[SFF]
Language and verbal memory are based on abstractions from
the experience of immediate sensory
perception. These verbal abstractions are also what knit
together the fleeting perceptions, providing continuity, context
and meaning. It is what allows
organization and relationships in space and time to be expressed,
to go beyond the concrete to the conceptual, to create a world.
[Can't this be done *internally* with images?] [SFF]
Words may be simple labels, or they may be "names" which
carry meaning, i.e. relationship and category. Similarly verbal
memory functions at both levels, and words may be recalled as
labels without any sense of relationship, context, or meaning.
[SFF]
The memory of smells is one of the deepest and most powerful,
being able to bring up associations even in persons who are long
term amnesiacs. It is probable that these are stored by the lower
layers of the brain, rather than depending on the multistage
processes involving the medial temporal
lobes.[AM]
Short and long terms memories are different modes of thought, shown
in part by disorders in which one is impaired while the other is not. This
is not due to memories being stored in different places, but to their
being different mechanisms, or modes of consciousness involved.
In some cases patients can recall events up to a certain period,
after which they cannot. It is suggested that longer term memory
involves a process of abstraction from immediate experience, and that
the failure to hold a coherent experience of the present (e.g. short
term memory loss) will prevent the formation of new abstractions,
i.e. new long term memories. There may be a tendency for long term
memories (years in the past) to be more of patterns, generalized
repeated experiences, than specific events. [SFF]
There may also be an emotional loss as well, with patients saying
that they haven't felt alive for a long time. This may be related to
a loss of a coherent body image and
therefore of the present "self" and the emotional response to present
experience. The person may become an automaton, who only acts through
imitation, and has no sense of like or dislike for people, food, or
anything else. [Perfect non-attatchment, but due
to a lack of connection or consciousness]. [SFF]
Goleman refers to "working memory" which is like a workspace buffer,
where we keep information we need for present time analysis, thought,
or any other task. This is held in the
neocortex and can become disabled by strong emotional upset. I.e.
we loose the ability to think clearly, or at all, due do some emotional
stress. [EI]
Removal of the hippocampus may result
in the loss of intermediate memory (over 15 minutes), while the long term
memory remains. [SFF]
In patients who lack long term memory, it seems that they can only
relate objects or events directly to themselves, but not to each other.
While they can understand complicated descriptions of things that
relate directly to them, they cannot follow well descriptions of other
events etc. Abstractions tend to lack meaning, only the concrete, which
can be directly experienced has meaning. To people who have only
immediate perception, or only abstract understanding, neither can
have the same sense that they have for people who have both. This
is because they help to define each other, with the immediate giving
rise to the abstract, which in term contributes to the perception of the immediate. It is suggested
that when both are operating, they are always operating together, not
alternately. Thus in persons who "have" only one or the other, their
consciousness is not that of one mode
of memory or the other, but must be entirely different, which leads
to the abnormalities even in the faculty that remains active. It is
cautioned that because of this probable difference in consciousness
the patient's awareness behind his or her words is likely to be
quite different than that of other people. [SFF]
The formation of "meaningful" or "conscious" long term memories,
involves the complex synthesis of a scene or context out of individual
perceptions. This can be held for only a few minutes in the short term
memory, before it must be transfered to long term memory. Each of the
three phases is necessary for a properly functioning long term memory
to be formed. The third step apparently involves the use of the temporal lobes. [AM]
When memory is interfered with due to the growth of a tumor, inducing
long term amnesia (i.e. no new long term memories are formed), the amnesia
may spread to early memories as well. [AM]
We may derive our sense of time from the differences between the two.
It is also suggested that the past and present "selves" are different.
In seeing people a sense of time is based on the motion we see around
us. In blind people however, the sense of time can only be based on the
motion of the body, and seems to expand, becoming longer. The sense of
the present weakens and the future fades. The interaction of short and
long term memory, comparison between the two, may give rise to a sense
of time, which is itself an integral part of memory. Both are then
integral in forming our consciousness,
or awareness and understanding. [SFF]
The old idea that memories are stored as images in specific nerve
cells in the brain is not supported by the
experiences of persons with brain damage. However it does seem that
groups of neurons develop an affinity for certain types of perceptions, or for certain aspects of
them. These groups cluster in sheets (maps), with other groups that
have an affinity for related perceptions. The affinity of the groups
is formed through experience, or perhaps a process of selection, in
which they are tuned to specific sensory inputs, in part by repetition.
This tuning process implies that no two brains will ever be the same.
The maps, in turn are connected by networks which coordinate their
response to images and events, resulting in a coherent response.
This process is likened to a jazz ensemble in which each musician
is interacting with each of the others to produce a coherent sound.
These coherent responses are associated with the physical neural synchronization in which groups and
networks of neurons oscillate at the same frequency all over the
brain. These form a building block of
consciousness.[SFF]
There is evidence, and anecdote, that some types of memory
associations are favored for reasons of basic survival. In
particular the experience of nausea is associated predominantly
with the memories of smell (taste). This is a basic survival
mechanism, that which made you sick is dangerous to eat. However,
even when the cause of the nausea is not the food (e.g. the
tossing of a boat) any smell or taste of food during that time
will become an embedded association (the banana boat story). [HB]
The visual memory of some autistics is apparently highly
associative in nature, or perhaps it is the methods of retrieving,
or regenerating the memory. This can lead to scattered and
wandering discourse, in which the speaker frequently goes off
on tangents that may be related to the initial topic only by
a series of verbal, visual, or experiential, associations. [TP]
Memories may be associated by mood as well as content. [EI]
Creation of Memories
Physical Memory
Semantic Memory
Implicit Memory
Visual Memory
Verbal Memory
Olfactory Memory
Short and Long Term Memory
Short Term Memory
Long Term Memory
Time
Neuronal Memory
Associative Memory
Page Created, February, 1998. AHM.
Last updated September 15, 1999. AHM.
© Alan McAllister