Memory resides at the heart of our brain, in an incredibly complex and efficient machinery. Here’s how it all works.
The human brain is an absolutely formidable machine. This one can log a million billion bits, far more than any computer, but unlike the latter, it doesn’t log everything you want, only potentially useful information. To manage all this, several memories are used, in different cerebral centers. The memory is distributed, perfectly organized. Here’s how it all works.
Overview of the brain
The human brain is divided into four main areas: the brainstem linked to the spinal cord, the cerebellum at the back of the skull, the limbic system in the center – with the hippocampus, amygdala and striatum -, and both hemispheres on the surface.
These two hemispheres each have four lobes. The frontal lobe, for reasoning and planning, also responsible for language, voluntary movements and self-awareness, it is the seat of our personality. The parietal lobe is the seat of speech and sensory perception. The occipital lobe, on the other hand, is the area for decoding visual information. Finally, the temporal lobe allows us to process sound information, to understand the meaning of words and to memorize our memories.
The hippocampus, an essential crossroads of memory
One of the most important areas of the brain for memory is the hippocampus, in the old (limbic) brain. Shaped like a sea horse, the hippocampus plays a fundamental role in forming our memories, but it does not store them. See it more as a crossroads. It changes with our intellectual activity. The more you use your memory, the larger the hippocampus!
long term memory
Long-term memory is actually a combination of several types of memory. There are two broad categories: declarative or explicit memory and implicit or non-declarative memory. Each appealing to a specific part of the brain. If declarative memory is said to be “explicit”, it is because it is thanks to it that we consciously remember things. It brings together “episodic” and “semantic” memories and it also solicits cortical structures and nervous pathways.
Episodic memory, on the other hand, is the memory of our memories. Each moment is made up of sensory memories and it is the hippocampus that binds them together to recompose a global memory. And it can happen that this bond is so strong that the memory resurfaces by a simple smell, a song or other.
Semantic memory is that of meaning and knowledge, in constant interaction with episodic memory. It separates sensitivity from memory to retrieve general information. It does not need the hippocampus, it activates the frontal cortex and the temporal cortex.
The most emotionally intense memories activate an additional area: the amygdala. We thus remember the emotions associated with a memory and we feel them each time the memory comes up.
The cerebellum, the ganglia and the cortex are solicited by procedural memory – a type of implicit memory -. We use it when we acquire know-how, to be able to accomplish certain tasks without thinking about it.
short term memory
Short-term memory allows us to retain information very temporarily – maximum 45 seconds -. After this time, the brain decides either to forget it or to transfer it to long-term memory. Several areas are used for this memory.
The prefrontal lobe, first of all, when we want to accomplish a task or solve a problem. It is particularly developed to offer us our ability to anticipate.
The phonological loop makes it possible to retain for two short seconds a verbal information read or heard. Beyond that, it must be repeated to retain it for a few more seconds.
Visuo-spatial memory operates similarly to the phonological loop, but it concerns mental imagery and solicits the right hemisphere, unlike the first which solicits the left hemisphere.
Working your brain regularly is important in many ways. For this, you need a healthy and varied diet, but also to protect yourself from stress, play sports and train your brain.
The idea is not to restrict yourself to restrictive and boring exercises, but to play with your memory, to mark your brain with an image that amuses. The smartphone can also be a very useful support for working the memory. Luminosity, Fit Brains Trainer or NeuroNation are very effective apps. You can also do concentration and memorization exercises every day. Take a list of words (races, names or whatever), observe it and recite it in order.
To properly retain any information, you must first understand it. And to anchor it, you need a link, linking it to something well known to you. This will allow you to store it correctly and recall it easily. The more outlandish the links, the greater the chances of memorization.