Source: Pennsylvania State University
Summary: Researchers suggest different parts of the brain mature at different times, which may help to explain impulsive behaviors in adolescence.
The research team from the Pennsylvania State University and the University of Pittsburgh discovered that the brain’s salience network, a group of regions that work together to help people assess the importance of stimuli in their environment, played a key role in regulating self-control behavior when participants were motivated by incentives. Most previous research in this area had focused on one region of the brain. Rather than using this approach, the team sought to investigate communication among different regions of the brain. They designed an experiment that combined eye-tracking and functional magnetic resonance imaging tools to get a better view of what brain regions were involved in a task requiring self-control. The study findings were published in the journal NeuroImage.
One hundred forty participants aged 10 to 25 years took part in the study. Study participants had to look away from a dot that appeared on a screen, a common neurocognitive test known as an antisaccade. The ventral striatum, a key player in reward processing, is often more active in teens than children or adults when given rewards. Older individuals recruited the salience network to a greater extent when preparing to complete the task, which the scientists suggest may help increase their inhibitory control. By contrast, ventral striatum activity was greater in teens in the outcome phase, yet this activity was not associated with inhibitory control. This finding is consistent with the idea that greater ventral striatum activity in adolescence may be linked more with greater experience of the third component of rewards, pleasure after an outcome has occurred.
Asst. Prof. Michael Hallquist said, “This is one of the first studies to look at the integration of reward circuitry and cognitive control from a functional network perspective” and further added, “Rather than testing Region A or Region B, our study describes the intrinsically connected networks, like the salience network.”
More Information: Daniel J. Simmonds et al, “Protracted development of executive and mnemonic brain systems underlying working memory in adolescence: A longitudinal fMRI study”, NeuroImage (2017). DOI: 10.1016/j.neuroimage.2017.01.016