doesn’t. Researchers are just now teasing apart how the arousal,
approach, and inhibition systems might work differently in high
sensation-seeking individuals. They have found some intriguing
clues in non-humans, including rats.High Sensation-Seeking Rats?
In the early 1990s, Franc ̧oise Dellu and his colleagues at the Scripps
Research Institute in La Jolla, California, examined sensation-
seeking in rats.^23 They wanted to know if rats, like humans, had
different levels of sensation-seeking.
They used newly born Sprager Dawley rats – you would
recognize them as the white ones with beady red eyes – commonly
used for medical research because of their calmness, which makes
them easy to handle. Researchers plopped them into a maze to see
how they reacted in a stressful situation. For a human, it would be
equivalent to being plucked out of your apartment and placed in
a corn maze at random points during the day. The researchers were
curious to see how the rats responded.
What they found were two very different kinds of rats.
Some attacked the new environments with gusto, exploring every
corner of the maze. Researchers called these high responders, or HR
rats. Others seemed to be less active in these new environments and
explored less. These were the low responders, or LR.
HR and LR rats seem to have different inborn “personal-
ities.” The HR rats did more than just attack the mazes more
actively. They also explored more parts of the maze, ate their food
more quickly, and, when given the opportunity through small
tubes, delivered themselves stimulants more often. They were, in
essence, high sensation-seeking baby rats.
What’s more, the researchers discovered an important biolo-
gical difference between the HR and LR rats. The stress hormones that
were released served as a stimulant to engage in the stressful behavior.
The researchers found that the HR rats’ stress hormones were reinfor-
cing to the HR rats. In other words, they seemed to seek out stressful
situations. How could this be possible? Well, it seems that HR rats
respond differently to stressful situations than their LR counterparts.
Like the rats, high sensation-seeking humans clearly
respond to stress very differently than their low sensation-seeking
friends. One explanation may be that high sensation-seekers
respond differently to the neurochemicals associated with the41 / Born to Be WildDownloaded from https://www.cambridge.org/core. Access paid by the UCSF Library, on 11 Nov 2019 at 14:20:40, subject to the Cambridge