I've been thinking about this also, it seems to me that there are layers of memory, that these levels or layers determine the level of importance,
but as always , a big factor when we are grown or have programs, the information sometimes bounces off or doesn't sink in, because our internal organization is fixed to ideas and so on, preventing assimilation of information, such as the case of cognitive dissonance, consciously or unconsciously refusing the information or putting it on a memory level where it shouldn't belong.
From memory to learning is a long trench, i wanna say the layers or levels of memory are set by mechanical factors, to organize information according to the importance in life, if the information is crucial to one's survival such as eating the body's instinctive center will make the association for us, if is something non escential such as playing a musical instrument the all three centers have to act in unison and memory must be forced, but in the case of the musical instrument you have the person who likes it and the person who doesn't.
The person who likes it, finds it easy to memorize because the joy and pleasure associated with the learning and experiencing of the music,
The person who does not like it, finds a wall or walls, that refuses and rejects the entry of the information or makes it many times less likely to be absorbed.
regardless whether it is the same brain and the same body type, the brain simply refuses to assimilate the information as one level or another, but the same happens when a person who likes music finds himself frustrated by feeling "stuck". the information bounces off and doesn't sink in.
In all cases the emotional center is mechanically design to assist memory with emotions.
In cases where the learning is forced also the reward mechanism is also at play, thus the memory is also stored,
Also , different emotions give character to the information being stored.
Found this on _http://www.human-memory.net/processes_encoding.html
Encoding is the crucial first step to creating a new memory. It allows the perceived item of interest to be converted into a construct that can be stored within the brain, and then recalled later from short-term or long-term memory.
Encoding is a biological event beginning with perception through the senses. The process of laying down a memory begins with attention (regulated by the thalamus and the frontal lobe), in which a memorable event causes neurons to fire more frequently, making the experience more intense and increasing the likelihood that the event is encoded as a memory. Emotion tends to increase attention, and the emotional element of an event is processed on an unconscious pathway in the brain leading to the amygdala. Only then are the actual sensations derived from an event processed.
The perceived sensations are decoded in the various sensory areas of the cortex, and then combined in the brain’s hippocampus into one single experience. The hippocampus is then responsible for analyzing these inputs and ultimately deciding if they will be committed to long-term memory. It acts as a kind of sorting centre where the new sensations are compared and associated with previously recorded ones. The various threads of information are then stored in various different parts of the brain, although the exact way in which these pieces are identified and recalled later remains largely unknown. The key role that the hippocampus plays in memory encoding has been highlighted by examples of individuals who have had their hippocampus damaged or removed and can no longer create new memories (see Anterograde Amnesia). It is also one of the few areas of the brain where completely new neurons can grow.
Although the exact mechanism is not completely understood, encoding occurs on different levels, the first step being the formation of short-term memory from the ultra-short term sensory memory, followed by the conversion to a long-term memory by a process of memory consolidation. The process begins with the creation of a memory trace or engram in response to the external stimuli. An engram is a hypothetical biophysical or biochemical change in the neurons of the brain, hypothetical in the respect that no-one has ever actually seen, or even proved the existence of, such a construct[...]}
Menna
It is very possible that your brain is arranged in a way so as to function under pressure, because this level of stress aids the memory process, as a result of the incoming information not causing enough emotional impact so as to be remembered or stored in the brain. I guess that is very common, but when you explain that some days and some passages or answers you can remember more or less, is because the factors you mention prevented so, so the factors themselves are such that interfere with the learning process because the body emotion and mind of yours was more concerned with processing the aforementioned factors than in the actual study, could very well be that the factors compromised part/parts of you (I's) , physical hunger or had a more important emotional/psychological value than the study.
To me personally it was more important learning the logic behind it so then everything else falls into place, like a map, so if it was math i never did good memorizing bits and pieces, until i understood the logic behind it, i could then learn with relative with little effort. Learning is more important to me that memorizing in the sense that is makes it many times easier. an example is the logic behind multiplication and division of fractions, it never made sense to me until i turned the attention to the actual numbers and the logic behind the formula rather than memorizing the formula. . In that case, then the reward mechanism works by means of anticipation and other processes involving emotional reward and a second effort to actually understand.
A note about psychopaths _http://discovermagazine.com/2016/june/12-psychopath-and-the-hare
Psychopaths' brain scans exhibit little change between neutral and emotional words, and they have much less brain activity, compared with a non-psychopaths brain.
Psychopaths can also make use of memories, as described in the link about memory, the information is stored all throughout the cortex and the amygdala stores the emotions associated with the memory, however the way they are configured does not lead to learning by conscious effort, or lack of emotional significance to an event so their brains allows them to memorize without emotional boundaries, or emotional categorization , but therefore in much worse quality, limited to only physical impulses rather than a full spectrum of sensations possible to non psychopaths.
