Neuroscience researchers link individual preferences to neuronal brain activity
Archived article from Sep 26, 2005
By Peter Haigney
Life is full of choices. But how do individuals know what their preferences are and how do they act on them? And what leads mothers to make choices that benefit or harm their offspring? Based on research performed using laboratory rats, a team of neuroscience researchers in Newark suggests that an intricate system exists within the brain for establishing individual preferences, which ultimately impacts choices.
In a September 2005 article in the journal Neuroscience, neuroscience professor Joan Morrell and her colleague, Brandi Mattson, reveal that individual preferences can be linked to the activation of specific sets of neurons within the brain.
The researchers used postpartum rats to analyze how the mother rats’ brains functioned when they selected an environment associated with their pups or another environment associated with cocaine. In the experiment, rats learned over four days in which distinct environments they had access to their pups versus where they had access to cocaine. Following a 24-hour wait, the rats were given the opportunity to choose either environment.
Using a computer program, the researchers recorded the rats’ time and activity in each chamber, then analyzed and recorded the rats’ brain activity at the time of their environmental choice. According to Morrell, the analysis revealed clear patterns of neuronal activity when the rats made their choice and showed that specific brain regions were active when the animals were making one choice (pups) in favor of another one (cocaine). The researchers determined this by tracking the presence of proteins that demonstrate the activity of neurons within the brain.
“This approach provides a snapshot of what was going on in the brain at decision time, which is preferred pups or cocaine,” Morrell notes. “Understanding what is going on in the brain at decision time is crucial since preference for the environment related to her pups is likely to lead to pup care by the mother rat, while preference for the environment related to cocaine is likely to lead to pup neglect.”
These findings may be significant because they establish a link between individual preferences and innate brain activity, but Morrell cautioned that it would be a leap to use these results to provide a model for the higher cognitive processes, such as critical thinking and belief systems that humans possess.
“The results, however, demonstrate the general principles of how the nervous system mediates such important decisions and these principles apply in the nervous system of all mammals including humans,” Morrell explains. “With this approach we can determine the ground rules for the function of the mammalian brain in such decisions.”
Return to the Sep 26, 2005 issue