Understanding Memory

A common misconception of what memory is, is that the mind has the ability to make a photograph of experiences. In fact memory is more than what we consciously recall about events from the past. It is the way past events affect future functions.

The brain is composed of spider web neural networks that fires patterns, called a neural net profile. When the neurons in our brain make connections, they fire. If they fire repeatedly, these connections between the neurons strengthen and enhance the possibility of learning. So memory is the repetition of firing of certain neuronal networks. In other words, experience shapes the brain and learning is experience dependent.

The infant brain has an over abundance of neurons with few synaptic connections at birth. The brain learns from implicit memory, which is the first impressions a baby makes from the first day of his life and those remain available to us throughout our lives. Implicit memory happens automatically. The baby does not say “oh yes, I remember that toy, it made a loud noise before”, when he has a fright as it happens again.

The brain constantly scans the environment and tries to determine what comes next. It distinguishes between familiar and new information which is the mind’s attempt to “remember’’ the future. When the next moment is anticipated, the brain is ready to handle the environment and helps us to plan for the future.

By the second birthday toddlers have developed a new skill. They talk about recollections of the day’s events. This kind of memory includes knowledge of their world. This development is experience dependent. This kind of memory is called explicit memory.

Working memory is what we are thinking of at a specific moment. Remembering the phone number of a shop you need to call once only, is an example of working memory. You hold on to those digits just long enough to dial the number. There is no rehearsal of the information. Unfortunately information for exam papers is stored as working memory and the information is held onto until  just after the exam only. There is a time limit to working memory. If working memory persists, you are bombarded with irrelevant information from the past.

How do items become part of long term memory? An example of long term memory is remembering a close friend’s phone number, which should be placed in long term storage. How does this happen? New associations link up with existing memory traces and form new clusters. The new clusters depend on REM sleep stage, which is an attempt to make sense of the day’s activities.

Information has to be encoded into long term explicit memory to last longer but may be affected by trauma. For example, if someone had been in an accident in January. He may retrieve information from October to December, but after that he can’t remember, which is called retrograde amnesia. Why? Retrograde amnesia is information which did not have a chance to be integrated and encoded into the long term explicit memory. The patient involved in the accident will be able to remember old info that had been encoded before the accident.

Remembering and forgetting: Forgetting is an essential aspect of explicit memory. If we remember everything we encoded, our working memory would be flooded and normal functioning will become impaired.

Emotions also play a role in memory. Information with a moderate or high degree of emotional intensity is labeled as important and has a greater chance to be remembered but when we are overwhelmed by emotions and terror, we inhibit the memories because we feel bombarded and confused. If the degree of emotional intensity is too high, we rather forget traumatic information.

Sleep plays an important role in memory. The brain sometimes tries to recollect blocked memory during REM sleep and therefore we have nightmares in order to reorganize traumatic information. Sleep and more important REM sleep, is crucial for memory consolidation.

Memory can also be enhanced by a technique called neurotherapy.

For more information : Dr Annemie Peché 0823356133