Yehouda Harpaz email@example.com 9 Sep 94 www: http://human-brain.org/cognition.html hypotheses.html related texts
The ERS is made of a large subset of the cognitive system ( 1--50 % of the total micronodes). All of these micronodes get input from a center, which is controlled by a smaller set (the size of a cognitive element). The center control the level of activation in the ERS, and can also attenuated the activation signals from and to micronodes in the ERS. The inhibitory effect of the micronodes of the ERS on the rest of the System is very weak.
In normal operation, the center of the ERS keeps active relatively small number of micronodes (0.0001-0.01 of the total in the ERS). These micronodes do not have any specific pattern. This can be done by keeping the micronodes just below threshold level, and by attenuating down the activation into the ERS
As a result, at any moment some of the micronodes in the ERS are active. These micronodes constitute the episode set. The strength of the connections between the episode set and the other active micronodes in the System is increased, and also the connections inside the episode set. Since the micronodes which constitute the episode set are continuously changing, the episode set of any point in time is overlapping with both the preceding and following episode sets, and there are strengthen connection between the non-overlap micronodes of two neighbouring episode-sets.
When the System need to do an episodic recall from the immediate past (e.g. Recall words from a list shortly after it was read), it does this by:
- attenuating the sensory input.
- Increasing activation in the ERS.
As a result, activation will spread from the current episode set to the preceding episode sets. This will send activation to the sets that were active at preceding time. If these matches the activation from the other cues (words, medium of input, etc.), these sets will become active (== the corresponding cognitive element will be recalled).
The activation in the ERS can continue to flow backwards(3), to recall more sets, but there is nothing that directs it to go only backwards in time. As a result, the activity become very diffused, and completely episodic recall cannot go much back in time. However, there are always additional cues active in the System, and the activation from these cues gives preference to the appropriate micronodes.