Articles about Brain and Memory
How Well Do You Know Your Brain and Memory?
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Just a Spoonful of Sugar?
Can sugar make you forgetful? Slow your brain? Create fuzzy thinking? A recent study suggests sugar sabotages learning and memory. We are all familiar with the ‘too much sugar causes obesity’ message, little attention has been paid to its impact on mental health. This is changing.
New Zealanders consume a whopping 57.5 kg of sugar a year, more than double the intake recommended by the World Health Organisation. That that figures comes from 2005, so I expect it has increased since then. That’s about half a cup a day. Imagine pouring half a cup of sugar into a pile every day, for 365 days! You would have a sugar mountain.
So, what’s the link between sugar and memory? Neuroscientists have long known that short-term memory problems are associated with the slowing of blood flow to the memory-crucial hippocampus during the ageing process. Recently, Scott Small of the Columbia University Medical Centre discovered high blood sugar levels created the same problem. A consistently high sugar level causes the body to pump out excess insulin, causing inflammation and excess oxidants, stressing the brain. It’s true that coffee with sugar may have you up and running in the morning, but over the long term, consuming a large volume of sugar, or foods that are quickly converted to sugar by your body, will prematurely age your brain.
Look out for hidden sugars – fructose added to soft drinks, in bread, condiments, sauces, and so on. Check those food labels. Nutritionists are particularly concerned, not about the naturally occurring fructose in fruits, which also contain important antioxidants, but by the high-fructose corn syrup that is added to manufactured food products as a sweetener and preservative.
For brain health, look for low-sugar, nutritious and delicious alternatives. You will soon notice sharper, clearer thinking.
Does my brain have a special place to store memories?
No. Memory has multiple systems that work together to encode, store, and retrieve your memories. Different parts of your brain specialise in particular types of memory. For example, the left temporal lobe is adapted to remember verbal information, one strip of the frontal lobe processes information about movement, and the occipital lobes process visual information.
The brain is far too complicated to store all your memories in one place.
Can I lose my memory?
Memory is not an object you can lose! Rather it is a set of abilities that can be sharpened. There are several ways you can encode and store a memory, and the more ways you learn to do this, the easier it will be to remember later.
Did you know? There are:
Neural impulses can travel up to 250 miles per hour
A single neuron has up to 10,000 synapses or connections to adjacent neurons
Your brain grew by 250,000 neurons per minute before birth
There are about 100 billion neurons(grey matter) in your brain
You have about one trillion glial (white matter) cells in your brain
There are about one quadrillion synapses in the human brain
Do my memories accurately reflect my experiences?
Memories are not like photographs or snapshots of an experience. Everything that has happened to you since, and the time lapse since the experience, colours and changes a memory. Even the mood you were in when you had the experience affects how you will remember it. Our perspectives are always changing. Have you ever returned to a house you lived in when you were young? When you return as an adult you might be surprised at how small the house is - when you were a child it seemed enormous! The house hasn't change - your perspective has.
Should I be able to remember being a very small child?
Many people think there's something wrong with them because they can't remember anything until they were about four years of age, and even then the memories are fragmented. Often our earliest memories are tiny snippets, perhaps a special article of clothing, an event, or just an impression. The reason we usually can't remember being a baby or toddler is simply our developmental growth. In early childhood the brain is just developing and being 'wired' to be able to store and formulate memories.
The first parts of the brain to develop are those associated with your senses, and then the connections were made linking the senses. The last areas of the brain to mature, concerned with higher thinking and reasoning, take many years to develop and the process doesn't finish until late adolescence. It is not surprise you can't remember your first two or three years!
Is it true that we all lose our memory in old age?
Yes and no! There are some changes in memory as there are changes in the brain as we get older. Ageing universally affects all organs. It is true we lose neurons with age. It is true the risk of Alzheimer’s increases with age. However, a well-trained memory is resilient and shows fewer functional signs of ageing than the heart, the joints, the vascular system, and so on. All older people do not show memory decline at the same rate. Senior people who keep a rich, active lives generally show much less decline in both memory and thinking abilities. Many older people out-perform much younger people in mental abilities, including memory. The old adage “Use it or lose it” definitely applies to memory.
Can I learn in my sleep?
There have been many companies which sell CDs which purport to allow you to learn while you sleep. The idea is that you can play the CD while you sleep and you will somehow miraculously awake with the information absorbed. Unfortunately, one of the most important components of learning is paying attention! It is much more effective to study or read when you are awake! However, sleep does appear to be important in consolidating memories and research is emerging which shows the brain's hippocampus is hard at work 'offline' during the deepest levels of sleep.
Why don't I feel pain immediately when I burn my finger?
Have you noticed the delay between burning a finger and the time you feel the actual pain? This happens because different types of nerves carry information at different speeds. The initial touch flies along a thick nerve at more than 250 miles an hour. The actual sense of pain is carried along thinner, slower nerves.
How do thoughts travel in my brain?
Your brain works by passing signals through a very complex network of billions of nerve cells. These electrochemical signals pass from cell to cell across synapses. Neurons connect to each other through special extensions called dendrites (which receive the signal) and axons (which send the signal). The receiving dendrite passes the signal on to the cell body which processes the signal before passing it along its axon to the next neuron. Every neuron in your brain has between 1,000 and 10,000 synapses located on its dendrites – it is a wonderfully efficient system!
What is a synapse?
Neurons don't touch one another, even though you have millions of them. A gap called a synapse separates the axon of one neuron and the dendrites of the next. The signal must leap across the gap onto the next neuron to ensure the signal continues on its path. It is like a domino effect. Through a series of chemical and electrical events the signal is shuttled through the synapse to the next neuron and is picked up by the nearest dendrite. The entire impulse passes right through the neuron - dendrites to cell body, cell body and down the axon, and across the synapse in about seven milliseconds. That's faster than a lightning strike. And remember, this is taking place literally millions of times in your brain simultaneously!
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