Tuesday, February 21, 2017

Forming new habits. Part 4: Memory.

Every habit you have is embedded in your memory somewhere. 

For part 1,2,3, go here, here and here

The more you practice a habit, the more the neural pathways are laid down. The pathway gets stronger and the memory becomes consolidated. As the neuroscience adage says 'neurons that fire together, wire together'.

But you memory is unreliable. It does not store fixed digital files, they change over time. Less like a digital photo and more like a painting you keep adding to and re-touching. Your memory of playing frisbee at 10 years old is different when you remember it at 14 years old to when you remember it at 50 years old.

You will have attachments to certain activities and foods beyond the utility of getting enough calories to survive and filling up your days with stuff to do.

Think of all your favourite comfort foods, they will probably have a memory attached to them. A roast dinner at your grandparents, a cheese sandwich after school, being given a certain chocolate bar as a treat. That food you had once on an amazing holiday.

And you may have an aversion to other foods because of a bout of food poisoning, or that time you got so drunk on Sambuca that you can never face drinking it again.

And you cannot escape your culture.

Pepsi vs Coca Cola.


In one famous study (McClure et all, 2004) the researchers compared peoples brain activation in an fMRI scanner when they were drinking Pepsi and Coca Cola. They are both essentially brown sugary drinks, so should activate the same areas of the brain.


When the participants didn’t know whether they were drinking Pepsi or Coca Cola the VMPFC lit up, an area of the brain that relates to taste.


However, when they were told they were drinking Coca Cola the DLPFC and hippocampus were activated. This didn’t happen when people thought they were drinking Pepsi.

The DLPFC is involved in working memory and perception based on previous experience. The hippocampus is involved in memory recall.

The coca cola was causing a memory recall in people, not just a taste sensation. The influence of culture and brand knowledge had made their brain remember Coca Cola (bear in mind they didn’t actually have to drinking Coca Cola for this to happen, they just had to think they were).



If you're American this is probably embedded in your memory, whether you want it to be or not.

Interestingly, the memory parts of the brain were not activated for Pepsi. And even the people who had a stated preference for Pepsi only showed activation of the memory parts of the brain when they though they were drinking Coca Cola.

This study was in the USA, and shows how much Coca Cola is part of peoples culture and upbringing in that part of the world.

For me this wouldn’t happen for Coca Cola, but it would probably happen for a cheese sandwich on white crusty bread and a cup of tea. These were more significant foods and drinks for me. Or possibly even Tizer, or Irn Bru if your Scottish!

If you're British and of a certain age this is in your memory. If you're American or Chinese this means nothing.


You cannot separate yourself from your culture or your memories which are hard wired into your brain.

Now think back to exercise. If someones memory of exercise is being made to do it at school, going for runs in the freezing cold and hiding behind the cricket pavilion for a cigarette; this is what they think of when they think of running. However, they may have more positive associations with dancing or cycling. Who doesn’t like riding their bike as a kid? Or swimming on holiday?

Spreading activation. Run = school = cold = bullying PE teacher!

Spreading activation theory is how your brain groups things together.

The networks in your brain seem to group words and objects together. Think pets, and you brain might thing dog or cat (in western culture) . You can prime someone by using associated words. Say the word carrot, and someone takes longer to recall the word doctor, say the word ‘nurse’ and they recall the word doctor a lot quicker.

Your neural network is dependent on your experience and your culture. You could prime yourself by associating certain feelings and words with exercise.

For example, for me running is not like the example above, but is running with my Dad as a kid - going to cool places, being outside.

And for a lot of new people going to the gym, especially women, I suspect that when you mention the words 'lifting weights' there neural network goes with the only examples it knows: weights = olympic = massive guys lifting massive weights = masculine/drugs. 

But could you change this, can you create a new pathway?

False Memories.

Elizabeth Loftus and her team were the first team to show you could implant a false memory in people, the memory was of being lost in a shopping mall as a child. It has to be a plausible memory, it  is less likely you could implant the memory that someone climbed Everest as a child.

They have also managed to do it with food (Bernstein et al, 2011). 

In one study (where the participants did not know it was about false memory, but about food preferences) the researchers managed to plant false memories in subjects to make them believe they had a bad experience with egg salad or strawberry ice cream ( up to 40% of participants). So much so that when offered these food one week or several months later they avoided them.

They also managed to plant a false memory about a 'healthy food', in this case, Asparagus, making them believe they love it the first time they had eaten it. They managed to convince 50% of participants they had loved Asparagus the first time they had eaten it. They then offered them a choice of foods to eat at a later date, the people with the false memory chose Asparagus more than those without the false memory. The participants with the false memory also said they would pay more for asparagus and choose it as a preferred food to have several months after the study.



You can be made to think you loved this the first time you ate it. Maybe you really did?

However, they were unable to plant false memories about a bad experience in the past or fake food poisoning with cookies (biscuits) or potato chips (crisps). This could be because these food are too tasty to give up and too common OR it could be intuitively as humans we generally know we don't get food poisoning from crisps.

Also, note they were not able to plant the false memory in everyone, more than half the people did not accept the memory.

The researchers also managed to do it for alcohol as well.

From a real memory point of view this makes sense, you aversion to Sambuca after that heavy night of shots years back or that terrible bout of food poisoning means you avoid a certain restaurant or seafood. And if you are allergic to something like peanuts or red wine your are very likely to avoid it.

Whats less clear is if you could deliberately plant a false memory in your self, while knowing you are actually doing it.

Be careful!

There is something called covert sensitization, which is essentially the idea of gradually associating a feeling of nausea/sickness with a food until you don't want it. Of course, this may result in you never wanting a food, even something as tasty as cheese. And lets not forget obesity and healthiness goes beyond one food group.

More useful could be the idea of making yourself want healthy foods more. And then associating these healthy foods with healthy words and healthy positive images in your brain.

You could make yourself remember that you loved running at school, you liked all vegetables as a kid and can't get enough of them.

Of course, there are techniques that people already use like hypnotism and NLP. Even though these have been considered fringe methods up until now, the research which uses quite basic methods of visualization shows there could definitely be some merit in some of these approaches.  

This is not going to happen over night, like all visualization techniques you have to practice.

What is real and not real?

There is another famous study, where one group of people learned to play a sequence on the piano actually sitting at the piano, and another group visualized practicing it. After 5 days, both groups showed an increase in the motor cortex where the fingers are controlled from in the brain.

Think about this for a second, not only did it show the brain in adults is plastic and can physically change when learning a new skill. It can be changed just by visualizing a new skill!

Now, you have to make your visualization targeted, you can't just sit there and pretend you are Elton John or Jimi Hendrix. You have to make your visualization a clear practice.

And one last study for you, Ganis et al (2004) Got one group of participants to look at a sketch of a shape, and another group to imagine the shape while in an fMRI scanner. There was a lot of overlap in the regions of the brain activated, in fact about 90%. There wasn't complete overlap, but there was a large amount of similarity.

This shows how powerful imagination can be.

Take home.

Hopefully, this has shown that your brain and habits are not fixed. After all people give up smoking and start exercising every day, and some stick with it.

You brain is plastic, you can change how you think about things and what your memories are 'telling' you.

Always remember that what you believe and remember and like are all products of the culture you were brought up in, at a certain point in history. And even though these things can be quite deeply embedded, there is no reason why you can't use strategies of visualization and mental imagery to change the things that are may be not working for you now.

You can visualize new skills, you can create positive word associations with healthy foods and exercise and probably even convince yourself how much you love vegetables. But, be careful, don't create a permanent aversion to cheese or coffee or bread - what could be worse. Live your life!



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