If I’m listening to a song with my husband and can’t remember the name of the singer, I’ll usually ask him if he knows.

In trivia quizzes I am usually useful for the medical questions but useless for the sports ones, that’s where a particular friend comes in handy.
This sharing of information we need and obtain from others is called “transactive memory”.

This was first described 30 years ago as meaning the division of the work or remembering shared information which is great as it frees us up from having to have duplicate sets of memory.

Today we now have so much more access to other information beyond our family members, books and encyclopaedias.
So where do we go to now when we have a question we want answered?

Well it’s quite likely to be Google.

The way we use the Internet today has drastically changed our ability to obtain information. But is it changing how our brain uses that information for future use as well?

That was a question that a researcher Betsy Sparrow recently set out to answer and her findings are really interesting.

And probably as you would expect, she found that people would often anticipate using the Internet to look up the answers to questions they weren’t sure of.

What was also interesting was that people were better able to remember the information, if they were told they would not be able to save it for future reference. Plus those who were asked to remember the information and where it was saved on their computer actually had better recall for where to find it than the actual information itself.

What does this mean?

Well perhaps using the Internet allows our brain to not have to do so much work, especially if we are confident the information will always be there.
We just need to know where to look for it. As another psychologist Roddy Roediger from Washington University said “why remember something if I know I can look it up again?”.

He also suggests that because we now have access to an ever-increasing information rich environment, this could be contributing to the so-called “Flynn effect”. This is the gradual increase in IQ score that has been observed over the last century.

What have you noticed for yourself or for your family in terms of their studying habits?

Do you think the Internet is useful in this way, or do you worry that we are outsourcing our brains too much to modern technology?
Let me know, I’d love to hear what you think.

Ref:
Sparrow,S., Liu,J., Wegner, D.M. Google effects on memory: Cognitive consequences of having information at our fingertips. Science. 14 July 2011 DOI 10.1126/science.1207745

Bohannon, J. Searching for the Google effect on memory. Science. Vol 333 15 July 2011 pg 277

Have you noticed how with age and UV exposure some plastics change, becoming more brittle? Well, it seems that as we get older, our plastic brain loses some of its plasticity too.

Our middle aged brains start to notice that it gets harder to learn stuff and keep it in our heads. It takes more effort to pay attention to what we are doing and more practice to embed new memories. We’ve found out that part of this is due to a slowing down of the brains’ processing speed and our increasing levels of distractibility. But new research now indicates that there is another reason for this; our lovely plastic brain becomes less plastic.

What does this mean?

When we talk about our brain being plastic, we are referring to the ability of neurons to form new connections (synapses) with other neurons. This occurs at the level of the dendrites, fine branches that sprout out from the neurons. These dendrites have “spines” which can develop into the new synapses, These synapses are formed and lost, as part of normal rewiring of the brain.

When we are learning new information, the neurons are actively forming new synapses. However some neural pathways or connections become redundant and without use or stimulation, these synapses simply get resorbed. This then frees up more space for yet more new connections to form, so it’s a great system.

The part of the brain we use for our higher level of thinking such as planning, organising, decision-making and our working memory is the prefrontal cortex. This is the part of the brain that is the last to fully mature in humans and is the area most likely to be affected by the effects of ageing.

High levels of stress and cortisol are known to cause neurons to shrink and for synaptic connections to be lost. Fortunately, once the stress is removed, our plastic brain allows new synapses to reform.

The effect of ageing on our brains plasticity.

New research from the Mount Sinai School of Medicine has shown that the brains of middle aged and elderly rats were less able to adapt to a behavioural stress response. In other words they were less able to learn from the experience. The neurons of the younger rats did change, showing normal plasticity and rewiring. Previous studies in 2010 examining the effect of the stress response in older rat brains had found a lack of a plastic response here as well.
Does this mean that stress doesn’t affect us as much as we get older? No, it means that with age, we lose some of our resiliency to stress; our brain is less able to respond, or to produce new synapses after the stress has been removed.

Our somewhat fragile and demanding prefrontal cortex is continually rewiring itself in response to all the stimulation and experience it encounters every day. Like plastic bottles however, our level of plasticity appears to diminish with age, we become less able to respond to either learning or stress.

With brain fitness training we are encouraged to “use it or lose it.”
To keep our mental sharpness and brain plasticity, it appears essential we continue to provide our brain with a variety of new and challenging activities.

Ref:
E. B. Bloss, W. G. Janssen, D. T. Ohm, F. J. Yuk, S. Wadsworth, K. M. Saardi, B. S. McEwen, J. H. Morrison. Evidence for Reduced Experience-Dependent Dendritic Spine Plasticity in the Aging Prefrontal Cortex. Journal of Neuroscience, 2011; 31 (21): 7831 DOI: 10.1523/JNEUROSCI.0839-11.2011

Parkinson’s disease is a brain condition where cells that produce a neurotransmitter called dopamine are lost in a particular area of our brain. Once 80% of these cells are lost those symptoms that we associate with Parkinson’s disease such as movement disorder and tremor become more apparent.
It’s also a common disorder affecting 2% of those over the age of 65 and 4-5% of those aged 85 years and older.

What hasn’t been known though, is what causes these special brain cells to die. Treatment for Parkinson’s has been targeted at replacing the dopamine that the brain can no longer adequately produce, but this does not address what has caused the loss of these brain cells in the first place.

Researchers have now discovered that a particular brain toxin, which occurs naturally in the brain, may be the missing link.

The brain toxin concerned is called DOPAL. It causes another brain protein, found throughout the brain, called alpha-synuclein, to form clumps. This clumping leads to more DOPAL being produced and this is then linked to causing dopamine producing cells to die.

Hopefully this will provide another small piece in the giant neuroscience jigsaw to help us understand better what causes Parkinson’s disease.

Ref:
W. Michael Panneton, V. B. Kumar, Qi Gan, William J. Burke, James E. Galvin. The Neurotoxicity of DOPAL: Behavioral and Stereological Evidence for Its Role in Parkinson Disease Pathogenesis. PLoS ONE, 2010; 5 (12): e15251 DOI: 10.1371/journal.pone.0015251

Trusting your gut. Can your gut influence your brain?

The discussion linking our mind and our gut has been around for a long time. We use the expression of “our gut feeling” when noticing our intuitive response to a particular situation which can guide our behaviour or reaction to it.

This gut-brain link is being investigated at the Brain-Body Institute where researchers are looking into understanding better, the relationship between our brain, nervous system and body disorders.

A new study in mice has shown how gut bacteria influence how the brain is wired for learning and memory. The bacteria we acquire in our gut just after birth appears to have a major impact on the development and function of not only the gut, but also the immune system, hormonal systems and metabolic systems. Using germ free mice they have shown how genes linked to learning and memory were altered in the hippocampus, the specialised area of the brain concerned with memory and learning.

In their studies they were able to show how gut bacteria determine how the stress response works, and this could produce an anxiety response in the brain. The findings were that the bacteria influenced the development of certain behaviours (such as anxiety) and produced neurochemical change in the brain as a result.

In other words gut bacteria can influence anxiety-like behaviours by altering the way our brain is wired.

Once we understand more about how this all the works the hope is to be able to devise more effective treatments for psychiatric disorders without having to use drugs. The current drugs available are limited in their use by the large numbers of side effects commonly experienced by people taking them.

Ref:
K. M. Neufeld, N. Kang, J. Bienenstock, J. A. Foster. Reduced anxiety-like behaviour and central neurochemical change in germ-free mice. Neurogastroenterology & Motility, 2011; 23 (3): 255 DOI: 10.1111/j.1365-2982.2010.01620.x

Your eyes meet across the room and in that instant you have made that connection. It’s taken all of 1/5th of a second for “love at first sight”.

We talk about our heart and love, but really it’s our brain, which needs to take the credit.

When we fall in love there are 12 areas of our brain all working together, releasing a cocktail of potent love chemicals: dopamine, oxytocin, adrenaline and vaspopressin.

Can’t stop thinking about the love of your life? Well that’s because your executive suite, where we use our conscious and intellectual thought, is highly activated to engage our thoughts of metaphors, body image and mental representation.

There is a difference too between the deep unconditional love between a parent and child where some common areas but also the middle part of our brain is activated.
In passionate love we use more of the reward system part of our brain as well as the executive suite, which is why thinking about the one we love makes us feel so good. Apparently it’s the same euphoria as using cocaine.

And what about when you’re not sure of the other’s affections? If you know someone likes you, you are likely to find them attractive too; more so than if you thought they only liked you a bit. But what makes someone really attractive is when there is that hint of uncertainty, that “je ne sais quoi” of possibility. So playing your cards close to your chest and not letting on how you really feel can really pique someone’s interest. Or maybe of course, he’s just not that into you.

Refs:
1. Stephanie Ortigue, Francesco Bianchi-Demicheli, Nisa Patel, Chris Frum, James W. Lewis. Neuroimaging of Love: fMRI Meta-Analysis Evidence toward New Perspectives in Sexual Medicine. The Journal of Sexual Medicine, 2010; DOI: 10.1111/j.1743-6109.2010.01999.x
2. E. R. Whitchurch, T. D. Wilson, D. T. Gilbert. “He Loves Me, He Loves Me Not . . . “: Uncertainty Can Increase Romantic Attraction. Psychological Science, 2010; 22 (2): 172 DOI: 10.1177/0956797610393745