Nav: Home

UMN Medical School researchers study how cues drive our behavior

August 02, 2018

MINNEAPOLIS, MN- August 02, 2018 - Do dopamine neurons have a role in causing cues in our environment to acquire value? And, if so, do different groups of dopamine neurons serve different functions within this process?

Those are the questions researchers at the University of Minnesota Medical School are looking to answer.

Recent research published in Nature Neuroscience by University of Minnesota Medical School neuroscientist Benjamin Saunders, PhD, uses a Pavlovian model of conditioning to see if turning on a light - a simple cue - just before dopamine neurons were activated could motivate action. The classic Pavlov model combined the ringing of a bell with providing a tasty steak to a dog that, over time, conditioned a dog to drool when the bell rang with or without a steak. In this research, however, there was no "real" reward like food or water, in order to allow researchers to isolate the function of dopamine neuron activity.

"We wanted to know if dopamine neurons are actually directly responsible for assigning a value to these transient environmental cues, like signs," said Saunders, who conducted some of his research as a postdoctoral fellow in the laboratory of Patricia Janak, PhD, at Johns Hopkins University.

Dopamine neurons, those cells in the brain that turn on when experiencing a reward. They are also the neurons that degenerate in Parkinson's disease.

"We learned that dopamine neurons are one way our brains give the cues around us meaning," said Saunders. "The activity of dopamine neurons alone - even in the absence of food, drugs, or other innately rewarding substances - can imbue cues with value, giving them the ability to motivate actions."

To answer the second core question, the researchers targeted specific segments of dopamine neurons - those located in the substantial nigra (SNc) and those located in the ventral tegmental area (VTA). These two types of neurons have historically been studied in different disease research fields - SNc neurons in Parkinson's disease, and VTA neurons in addiction studies.

Scientists learned that cues predicting activation of the two types of neurons drove very different responses - those predicting the SNc neurons led to a sort of "get up and go" response of invigorated rapid movement. The cue predicting VTA neuron activation, however, became enticing on it own, driving approach to the cue's location, a sort of "where do I go?" response.

"Our results reveal parallel motivational roles for dopamine neurons in response to cues. In a real world situation, both forms of motivation are critical," said Saunders. "You have to be motivated to move around and behave, and you have to be motivated to go to the specific location of things you want and need."

These results provide important understanding of the function of dopamine neurons related to motivations triggered by environmental cues. And this work contributes to the understanding of relapse for those struggling with addictions.

"If a cue - a sign, an alley, a favorite bar - takes on this powerful motivational value, they will be difficult to resist triggers for relapse," said Saunders. "We know dopamine is involved, but an essential goal for future studies is to understand how normal, healthy cue-triggered motivation differs from dysfunctional motivation that occurs in humans with addiction and related diseases."
-end-
About the University of Minnesota Medical School

The University of Minnesota Medical School is at the forefront of learning and discovery, transforming medical care and educating the next generation of physicians. Our graduates and faculty produce high-impact biomedical research and advance the practice of medicine. Visit med.umn.edu to learn how the University of Minnesota is innovating all aspects of medicine.

University of Minnesota Medical School

Related Neurons Articles:

How do we get so many different types of neurons in our brain?
SMU (Southern Methodist University) researchers have discovered another layer of complexity in gene expression, which could help explain how we're able to have so many billions of neurons in our brain.
These neurons affect how much you do, or don't, want to eat
University of Arizona researchers have identified a network of neurons that coordinate with other brain regions to influence eating behaviors.
Mood neurons mature during adolescence
Researchers have discovered a mysterious group of neurons in the amygdala -- a key center for emotional processing in the brain -- that stay in an immature, prenatal developmental state throughout childhood.
Astrocytes protect neurons from toxic buildup
Neurons off-load toxic by-products to astrocytes, which process and recycle them.
Connecting neurons in the brain
Leuven researchers uncover new mechanisms of brain development that determine when, where and how strongly distinct brain cells interconnect.
The salt-craving neurons
Pass the potato chips, please! New research discovers neural circuits that regulate craving and satiation for salty tastes.
When neurons are out of shape, antidepressants may not work
Selective serotonin reuptake inhibitors (SSRIs) are the most commonly prescribed medication for major depressive disorder (MDD), yet scientists still do not understand why the treatment does not work in nearly thirty percent of patients with MDD.
Losing neurons can sometimes not be that bad
Current thinking about Alzheimer's disease is that neuronal cell death in the brain is to blame for the cognitive havoc caused by the disease.
Neurons that fire together, don't always wire together
As the adage goes 'neurons that fire together, wire together,' but a new paper published today in Neuron demonstrates that, in addition to response similarity, projection target also constrains local connectivity.
Scientists accidentally reprogram mature mouse GABA neurons into dopaminergic-like neurons
Attempting to make dopamine-producing neurons out of glial cells in mouse brains, a group of researchers instead converted mature inhibitory neurons into dopaminergic cells.
More Neurons News and Neurons Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#541 Wayfinding
These days when we want to know where we are or how to get where we want to go, most of us will pull out a smart phone with a built-in GPS and map app. Some of us old timers might still use an old school paper map from time to time. But we didn't always used to lean so heavily on maps and technology, and in some remote places of the world some people still navigate and wayfind their way without the aid of these tools... and in some cases do better without them. This week, host Rachelle Saunders...
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.