Part of the answer lies in the brain's response to novelty. The brain is built to ignore the old and focus on the new. Marketers clearly understand this: If you watch closely, you will notice that heavily-played television ads will change ever so slightly after being on the air for a few weeks.
When this change is detected by the brain, our attention is drawn to the ad, oftentimes without us even realizing it. Novelty is probably one of the most powerful signals to determine what we pay attention to in the world. This makes a lot of sense from an evolutionary standpoint, since we don't want to spend all of our time and energy noticing the many things around us that don't change from day to day. Researchers have found that novelty causes a number of brain systems to become activated, and foremost among these is the dopamine system.
This system, which lives deep in the brain stem, sends the neurotransmitter dopamine to locations across the brain. Many people incorrectly think of dopamine as the "feel-good" neurotransmitter because drugs that create euphoria, such as cocaine and methamphetamine, cause an increase of dopamine in particular parts of the brain. However, a growing body of research shows that dopamine is more like the "gimme more" neurotransmitter. Some of the most interesting research on this topic has been done by Kent Berridge and his colleagues at the University of Michigan.
In this research, they videotape rats and then measure how often the rats exhibit signs of pleasure; some wonderful video of these "affective reactions" can be found at Berridge's web site.
Their research has shown that blocking dopamine in the brain doesn't affect how often the rats exhibit these pleasure responses. Each new stimuli gives you a little rush of motivation to explore, because it makes you anticipate a reward. Here's a graph that shows activity in your brain on this:. This potential that lies in new things motivates us to explore our environment for rewards. The brain learns that the stimulus, once familiar, has no reward associated with it and so it loses its potential.
For this reason, only completely new objects activate the midbrain area and increase our levels of dopamine. Unfortunately the human studies on this subject, such as the one mentioned above, are few and far between at this stage.
More studies have been completed on animals, but the research is still in early stages. Well these animal studies also showed that the plasticity of the hippocampus the ability to create new connections between neurons was increased by the influence of novelty—both during the process of exploring a novel environment or stimuli and for 15—30 minutes afterwards.
Their memory of the novel, familiar and very familiar images they had studied was tested after 20 minutes and then a day later. Subjects performed best in these tests when new information was combined with familiar information during learning. Current practice by behavioural psychologists aims to improve memory through repeatedly exposing a person to information — just as we do when we revise for an exam.
This study shows that revising is more effective if you mix new facts in with the old. What Poldrack and his colleagues discovered in their investigations provides information useful to journalists as they look for ways to engage the minds of readers, viewers and listeners through digital media.
This past October he began blogging for The Huffington Post about his research. As I set out to write about multitasking and information overload, let me admit that I am an information junkie. Why do I do things that place me in such clear social and physical peril? After all, it is built to ignore the old and focus on the new.
Marketers clearly understand this: Watch closely and you will notice that heavily-played television ads will change ever so slightly after being on the air for a few weeks. When our brain detects this change, our attention is drawn to the ad, often without us even realizing it. Novelty is probably one of the most powerful signals to determine what we pay attention to in the world. Researchers have found that novelty causes a number of brain systems to become activated; foremost among these is the dopamine system.
This system, which lives deep in the brain stem, sends the neurotransmitter dopamine to locations across the brain. Another neurotransmitter system in the brain, the opioid system, seems to be the one that actually produces the pleasurable sensations, though it has very close relations with the dopamine system.
Dopamine also is very much involved in learning and memory, which occur in the brain through changes in the way that neurons connect to one another. We know that the brain can change drastically with experience. Our behavioural results showed that risk preference was in turn associated with the NS score. Therefore, it is reasonable for us to suspect that the neural basis of risk prediction influences NS via a mediation effect of individual risk preference.
Because it is rational to consider neural activation the biological basis relating an individual trait e. To verify the relationship between the activation related to risk prediction and NS, an analysis of partial correlation between NS and the brain activation associated with risk prediction after controlling for individual risk preference was also performed with multiple comparisons correction Bonferroni correction with an adjusted alpha level, 0.
Then, bandpass temporal filtering 0. Next, to further reduce nuisance signals, we regressed out the average signals in the white matter and the CSF. The mask of white matter for each participant was determined from the high-resolution structural image using the FAST segmentation program of Functional MRI of the Brain software library www. The CSF mask for each participant was manually drawn according to the anatomical boundaries of the cortical structures of a standardised Talairach atlas brain, transformed onto the image space of the individual and then modified according to the cortical structures of the individual brain by referencing to the anatomical boundaries in the high resolution three-dimensional structural image.
These nuisance signals were used to account for fluctuations that were likely not relevant to neuronal activity. The resultant resting-state fMRI data were then subjected to functional connectivity analysis ROIs that were significantly correlated with the NS score were selected as seed regions.
The preprocessed resting-state fMRI time series were averaged within each seed region. Correlation coefficients r values were calculated among averaged time series of the seed regions and then transformed to Fisher z values. Then, the correlation between the z values and the NS scores was calculated. We performed a multiple comparisons correction with a threshold of 0.
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