Researchers have long believed that changes in brain neurons are associated with the formation of memories. Today, most experts believe that memory creation is associated with the strengthening of existing connections or the growth of new connections between neurons.
The connections between nerve cells are known as synapses, and they allow information carried in the form of nerve impulses to travel from one neuron to the next. In the human brain, there are trillions of synapses forming a complex and flexible network that allows us to feel, behave, and think. It is the changes in the synaptic connections in areas of the brain such as the cerebral cortex and hippocampus that is associated with the learning and retention of new information.
In one study conducted at the New York School of Medicine, researchers were able to observe synapse formation in the brains of genetically engineered mice. What they discovered was that in young mice, the tiny protrusions that sometimes develop into longer spines on the receiving end of neurons grew at a rapid rate. This growth rate coincided with the rapid development of the visual cortex. While a large number of these tiny protrusions eventually faded with age, many did continue their formation into fully-fledged spines.
Lead researcher Wen-Biao Gan explained in an interview with the science website WhyFiles.org, "Our idea was that you actually don't need to make many new synapses and get rid of old ones when you learn, memorize. You just need to modify the strength of the preexisting synapses for short-term learning and memory. However, it's likely that few synapses are made or eliminated to achieve long-term memory."
Clearly, maintaining a healthy brain and synapses is critical. Deterioration of synapses due to diseases or neurotoxins is associated with cognitive problems, memory loss, changes in mood, and other alterations in brain function.
So what can you do to strengthen your synapses?
- Avoid stress: Research has found that extended exposure to stress can actually interfere with neurotransmitter function. Other studies have found that stress shrinks neurons in the prefrontal cortex and hippocampus.
- Avoid drugs, alcohol, and other neurotoxins: Drug use and excessive alcohol consumption have been linked to synaptic deterioration. Exposure to dangerous chemicals such as heavy metals and pesticides can also cause synaptic loss.
- Get Plenty of Exercise: Regular physical activity helps improve oxygenation of the brain, which is vital for synaptic formation and growth.
- Stimulate your brain: You've probably heard the old adage "Use it or lose it." Well, it turns out there's a lot of truth to that when it comes to memory. Researchers have found that elderly adults who engage in mentally stimulating activities are less likely to develop dementia and people with higher educational statuses tend to have more synaptic connections in the brain.