Alcoholism in Family Affects How Brain Switches Between Active & Resting States
A new study, published in the journal NeuroImage, reveals that having a parent with an alcohol use disorder affects how your brain transitions between active and resting states regardless of your own drinking habits.
In general, after completing a mentally demanding task, the human brain reconfigures itself before resting. But in the brain of someone with a family history of alcoholism, this reconfiguration doesn’t happen.
The researchers compare the typical brain’s reconfiguration process to how a computer closes down a program after you’re finished with it. “The moment you close a program, a computer has to remove it from memory, reorganize the cache and maybe clear out some temporary files. This helps the computer to prepare for the next task,” said Dr. Joaquín Goñi, a Purdue University assistant professor in the School of Industrial Engineering and the Weldon School of Biomedical Engineering.
“In a similar way, we’ve found that this reconfiguration process in the human brain is associated with finishing a task and getting ready for what’s next.”
And while the missing transition doesn’t seem to impact a person’s ability to perform the mentally demanding task itself, the alteration might be related to larger scale brain functions that give rise to behaviors linked to addiction.
In fact, the researchers found that study participants without this brain process exhibited greater impatience in waiting for rewards, a behavior associated with addiction.
“A lot of what brains do is switch between different tasks and states. We suspected that this task-switching might be somewhat lower in people with a family history of alcoholism,” said Dr. David Kareken, a professor of neurology at the Indiana University School of Medicine and director of the Indiana Alcohol Research Center.
The study defined a “family history of alcoholism” as someone with a parent who had enough symptoms to constitute an alcohol use disorder. About half of the 54 study participants had this history.
Previous research has shown that a family history of alcoholism affects a person’s brain anatomy and physiology, but most studies have looked at this effect only in separate active and quiet resting states rather than the transition between them.
“In the past, we’ve assumed that a person who doesn’t drink excessively is a ‘healthy’ control for a study. But this work shows that a person with just a family history of alcoholism may also have some subtle differences in how their brains operate,” said Goñi.
In the new study, researchers measured the participants’ brain activity with an MRI scanner as they completed a mentally demanding task on a computer. The task required them to unpredictably hold back from pressing a left or right key. After completing the task, the subjects relaxed while watching a fixed point on the screen.
A separate task determined how participants responded to rewards, asking questions such as if they would like $20 now or $200 in one year.
After analyzing the data, the team developed a computational framework for extracting different patterns of brain connectivity between completing the mentally demanding task and entering the resting state.
The data revealed that these brain connectivity patterns reconfigured within the first three minutes after finishing the task. By the fourth minute of rest, the effect had completely disappeared. And it’s not a quiet process: Reconfiguration involves multiple parts of the brain at once.
“These brain regions talk to each other and are very strongly implicated in the task even though by this point, the task is already completed. It almost seems like an echo in time of what had been going on,” Kareken said.
Participants who lacked the transition also had risk factors consistent with developing alcoholism. These include being male, a greater number of symptoms of depression, and reward-impatience. A family history of alcoholism, however, stood out as the most statistically significant difference in this brain reconfiguration.
Source: Purdue University
Pedersen, T. (2020). Alcoholism in Family Affects How Brain Switches Between Active & Resting States. Psych Central. Retrieved on November 23, 2020, from https://psychcentral.com/news/2020/02/11/alcoholism-in-family-affects-how-brain-switches-between-active-resting-states/154122.html