What Is Memory?
Both learning and memory are a result of complex biochemical reactions.
The main processes involved in memory are encoding, storing and retrieving of information.
When a new memory is created the information is encoded and then stored in the brain. When the memory is recalled, the retrieval process brings that stored information back into conscious awareness. The capacity of the brain to change with learning is known as plasticity. Changes in Long Term potentiation ( increased action potential along a nerve) and changes in strength of synapse connections may last weeks or months. 2 types of receptor allow the influx of calcium ( regulated by magnesium) resulting in a strengthening of the synapse.
In 1968, Atkinson and Shiffrin proposed the stage model of memory. This theory involves the 3 different stages of memory, sensory memory, short-term memory and long-term memory.
Sensory memory this is the early stage of memory when the sensory information from the environment is stored for a few seconds. Up to half a second for visual memory and 3-4 seconds for auditory information. Some of this information then passes to short-term memory.
Short-term memory or active memory is the information in our current thoughts. Most of this is stored for 20-30 seconds (conscious mind) and if unattended to is lost. It can hold up to about 7 items for this time. Basically short-term memory is short term because the memory is transient and the accompanying biochemical changes transient. How long the short-term memory lasts depends on how long certain proteins are phosphorylated for (have a phosphate group attached). When protein enzymes remove these phosphate groups, the memory is no longer stored.
If attended to this information passes into long-term memory.
Long-term memory is the continued storage of information (unconscious), which is largely outside our awareness but can be recalled on request. Some of this information may be easier than other memories to recall. Long-term memory involves growth of new dendrites and synapse formation Long-term memory also involves changes in gene expression Forming and maintaining a memory involves multiple genes and proteins acting together to change and regulate the properties of the neurone and strength of synapse. Some changes in gene expression can occur as soon as 24 hrs after learning
The ability to retrieve information from long-term memory allows us to use these memories to make decisions, interact with other people and work out problems based on stored information.
It is believed that the frontal cortex and the hippocampus analyse sensory inputs and assess whether they are worth remembering. If they are worth remembering, the sensory information is received and carried along nerves at the end of which, chemicals known as neurotransmitters are released across the gap (or synapse) between nerve cells, only to be converted back to an electrical impulse in the next nerve. All these nerve cells are connected by a complexity of dendrites connecting with other dendrites. Every brain cell can form thousands of connections like this, giving a typical brain about 100 trillion synapses. At birth each neuron in the brain has approx. 2,500 synapses, by the time the child is 2-3, there are nearer 15,000 synapses per neuron. However this is about twice that of the average adult brain because as we age old connections are deleted by a process known as synaptic pruning Increase in the efficiency can last.
How Are Memories Created
Memories are created by repetition of the word/thought/action or by the release of chemicals associated with emotions. When a new word is learnt it is repeated enough times to strengthen and make circuit connections in the brain, similar to treading the same path through a field, the path becomes more established the more that it is used.
Memories are arranged in groups called clusters. This makes them easier to recall.
What happens when memory begins to fail?
There is a breakdown in the assembly process of memory. This actually appears at the onset of sexual maturity. As we age it is the synapses that become weaker. One of the main theories as to why this happens is that as we age, there is cell death in a small area in the front of the brain that leads to a drop in the brain chemical (neurotransmitter) acetylcholine that is vital for learning and memory.
Some parts of the brain are more vulnerable to the effects of aging, the brain shrinking and becoming less efficient as we age. Every 10 years there is a 5% loss of brain cells, totalling up to 20% by the eighth decade. Free radical damage can accelerate this process, poisons or other toxins such as toxic metals like mercury or aluminium, alcohol or cigarette smoke. Genetics also play a role too. Studies have shown that poor memory in older people can be improved using certain nutrition and improved still further by exercise and mental stimulation. Research has shown that as we get older brain stimulation encourages dendritic growth, while a dull environment impedes it.
Supplements To Improve Memory
Metabolics Memorymax is a complex formula, among which are ingredients known to contribute to normal functioning of the nervous system.
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