Impulsiveness during adolescence is not unique to us, according to a study which suggests that the brains of human and other primates go through very similar changes in teen years, particularly in the areas that affect self-control.
“As is widely known, adolescence is a time of heightened impulsivity and sensation seeking, leading to questionable choices,” said Beatriz Luna of the University of Pittsburgh in the US.
“However, this behavioral tendency is based on an adaptive neurobiological process that is crucial for molding the brain based on gaining new experiences,” Luna said.
Structural, functional, and neurophysiological comparisons between us and macaque monkeys show that this difficulty in stopping reactive responses is similar in our primate counterparts — who during puberty, also show limitations in tests where they have to stop a reactive response.
“The monkey is really the most powerful animal model that comes closest to the human condition,” said Christos Constantinidis of Wake Forest School of Medicine in the US. “They have a developed prefrontal cortex and follow a similar trajectory with the same patterns of maturation between adolescence and adulthood,” Constantinidis said.
Taking risks and having thrilling adventures during this period isn’t necessarily a bad thing, according to the study published in the journal Trends in Neurosciences.
“You don’t have this perfect inhibitory control system in adolescence, but that’s happening for a reason,” Lunsa said.
“It has survived evolution because it’s actually allowing for new experiences to provide information about the environment that is critical for optimal specialisation of the brain to occur,” she said.
Understanding the neural mechanisms that underlie this transitional period in our primate counterparts is critical to informing us about this period of brain and cognitive maturation, said Luna.
Researchers said that human neurological development during this time is characterised by changes in structural anatomy. There is an active pruning of redundant and unused neural connections and a strengthening of white matter tracts throughout the brain that will determine the template for how the adult brain will operate.
Specifically, by adolescence all foundational aspects of brain organisation are in place and during this time they undergo refinements that will enable the most optimal way to operate to deal with the demands of their specific environment, researchers said.
The development of neural activity patterns that allow for the preparation of a response seems to be a key element of this phase of development — and essential to successful performance on self-control tasks.
This all suggests that self-control isn’t just about the ability, in the moment, to inhibit a behaviour.
“Executive function involves not only reflexive responses but actually being prepared ahead of time to create an appropriate plan.”
“This is the change between the adolescent and adult brain and it is strikingly clear both in the human data and in the animal data,” said Constantinidis.
The researchers believe that this phase of development is essential to shaping the adult brain.
“It is important for there to be a period where the animal or the human is actively encouraged to explore because gaining these new experiences will help mold what the adult trajectories are going to be,” said Luna. (PTI)
