Which is most important in storing old memories?

6 posts / 0 new
Last post
Jitendra Sinha
Jitendra Sinha's picture
Which is most important in storing old memories?
Shampa
Shampa's picture
When a new information comes

When a new information comes to the brain, firstly it get processed in the hippocampal circuitry and then transfered to the various parts of the cerebral cortex specially frontal cortex.

Graeme E. Smith
Graeme E. Smith's picture
Actually I beg to differ here

Actually I beg to differ here.
When information first comes to the brain it is in the form of stimulation of the senses, which seem to split their connections some gonig directly to the cerebral cortex, and some going, via the thalamus to the cerebral cortex. This is raw stimulus and the hippocampus couldn't make sense of it, because it is too small.
Think of the Thalamus as being a router that allows us to either pay attention to the external stimuli, or to the internal stimuli generated within the brain. With this capability it is possible for the brain to pay attention to internal stimuli, while supressing external stimuli.
The Cerebral Cortex, then acts to divide and process the stimuli, creating a datafield called a Quale that allows instinctive reactions, such as orienting the body, and allows filtering of the datafield to focus on stimuli of greater salience. This promotes the formation of something called a "Functional Cluster" where neurons across the cerebral cortex resonate in synchrony at gamma frequencies. The process of selecting which functional clusters are more salient, triggers long-term implicit memory, which records the salient data-field elements possibly as a form of content addressable memory keyed to the stimuli that triggered the long-term storage.
Selection of the most salient data by selecting the functional cluster with the most salient data-field creates a quale that contains the information that instinct tells us is the most important for us to process. This then passes through the bottleneck and gets redescribed into phenomenally explicit memory.
It is only once the memory can be addressed explicitely that it can be broken down into specific data fields associated with specific memories. And it is only once that has happened that the data can be symbolically  addressed. The hippocampus is significantly smaller than the cerebral cortex, because it stores only symbolic references to the Cerebral Cortex contents. Therefore, hte hippocampus comes after the cerebral cortex.
Where it comes in, I believe is in the Declarative Memory. Essentially, episodal memory which the hippocampus CA3 area is known for is part of a complex of indexing techniques I call the Meta-index, which allows us to reference the contents of the cerebral cortex. This means that the hipposampus is involved not in the storage of long-term memory but in the indexing and therefore retrieval of it.

Jitendra Sinha
Jitendra Sinha's picture
Smith,

Smith,
Thanks for replying in details. Its really good to hear the topic with your views. That's great. Can you please suggest me some references like any review article or textbook where I can get this updated information.
Thanks for increasing our knowledge.

Monu
Monu's picture
Hippocampus is involved in

Hippocampus is involved in processing the incoming stimuli and then it sends the processed information to the related higher centers of brain. Hence the answer should be cerebral cortex in general.

Graeme E. Smith
Graeme E. Smith's picture
As you can see, I am an

As you can see, I am an amateur scientist or science enthusiast. This article while incisive is not all accepted by the scientific community in the way I presented it. It is my own fusion based on some hypothesis that have not yet met review. To find ou about the neuro anatomy of the nervous sysetm, you can look and very basic introductory articles. The major pathways of the brain have been known for some time, because they are obvious anatomically. The idea that the hippocampus is an index to Cortex memory is one of the basic controversies of science. So many scientists think that it has a direct role in storing memory that they talk as if it were proven when it hasn't been. The problem is simply that patients with the hippocampus or Medial Temporal Lobe which lies above it, removed have significant memory impairment and it is not obvious whether than imparement is due to loss of memory or loss of access to memory. The case of HM, is well documented, and most neuroscientists can comment on it. Results from that case were weakly suggestive that the knowledge still existed and could be accessed by implicit memory but that the access to it, via the declarative memory was damaged. The assumption that the hippocampus isn't large enough to deal with raw stimuli, can be tested merely by documentation of its size, it is about the size of your thumb, while the cerebral cortex, is about 1/3 of your brain. The idea that it stores symbolically can be referenced by the fact that it has been shown that place code addressing in CA3, often involves a single neuron at a time, and is size invariant, meaning that no matter how much knowledge we have about an object, it really only takse one cell to symbolize it at this point. If you think about it, that suggests a symbolic storage mechanism where each neuron symbolizes a different object, and content-wise there is no room for data, it must therefore be, I contest a way of mapping the data stored somewhere else. As you can see, I have reasons for discussing it the way I did, but, I can't give you direct references to any place else where you can confirm my particular interpretation, except in part.