OCT 01, 2015 4:48 AM PDT

Risky Business: Dopamine and the Brain

Choosing whether or not to buy a lottery ticket is one example of making a decision where some risk is involved. Dodging traffic across a busy street because there’s a coffee place on the other side also involves a risk vs. reward decision process, but of course the stakes are a bit higher. The human brain has evolved to weigh these factors and make appropriate decisions but how do animals process these factors? It truly is about finding out why the chicken (or the roundworm) crossed the road.
 An image of a sensory neuron in a roundworm
Research from the Salk Institute’s Molecular Neurobiology Laboratory was published recently in the journal Neuron and it reveals new information on how two chemicals interact in animals and how that interaction allows animals to balance risk and reward and learn how to best navigate their environment so that the needs for safety, food and shelter are met. The two chemicals that have to mesh precisely are dopamine, which controls reward and risk taking behavior and CREB, which is responsible for learning.
 
In a press release, senior author of the study Sreekanth Chalasani said, “Previous research has shown that certain neurons respond to changes in light to determine variability in their environment, but that’s not the only mechanism. We discovered a new mechanism that evaluates environmental variability, a skill crucial to animals’ survival.” 

The mechanism Chalasani  references is a circuit in the brain of roundworms that were used as subjects in the study. The circuit is comprised of 16 of the 302 neurons that roundworm brains contain. Researchers believe that this circuit of neurons is likely to be similar even in animals with more complex brains and hope the study results are the beginning of understanding some psychiatric and behavioral disorders.
 
The circuit, made up of 16 of the 302 neurons in the worm’s brain, likely has parallels in more complex animal brains, researchers say, and could be a starting point to understanding–and fixing–certain psychiatric or behavioral disorders.

The study results showed that much of the behavior seen in the roundworms was a result of their past sensory experiences, not simply the noise and light that went on around them. The mechanism that showed up clearly in the study demonstrated that the animals could tell what their environment was like and act accordingly, based on being able to sense the presence of food and when it was increasing or decreasing.
 
When food would decrease, dopamine, which would allow the worms to take more risks in seeking food would increase. This in turn would trigger an increase in the protein CREB which is responsible in part for making memories and retaining information that was learned.
 
Researchers experimented with placing the worm in areas with either large or small amounts of food and then using behavioral observation, genetic records, imaging and other methods to record how the animals responded to changes in the food supply. When amounts of food went down, dopamine went up to spur the worms on to look for more food. In conjunction with that, when the CREB protein was present in higher amounts, the worms learned faster where to go for the food.

Check out the video below to learn more about the study and what researchers hope will come from it.
 
About the Author
  • I'm a writer living in the Boston area. My interests include cancer research, cardiology and neuroscience. I want to be part of using the Internet and social media to educate professionals and patients in a collaborative environment.
You May Also Like
OCT 12, 2021
Health & Medicine
A New Way of Administering Deep Brain Stimulation May Increase Therapeutic Effect Duration in Parkinson's Disease
OCT 12, 2021
A New Way of Administering Deep Brain Stimulation May Increase Therapeutic Effect Duration in Parkinson's Disease
  Parkinson’s Disease (PD) is a specific type of neurological disorder that can significantly impact a p ...
OCT 14, 2021
Neuroscience
Facial Cues and Context Clues: Autistic Children May Overly Rely on Facial Expressions to Judge Emotion
OCT 14, 2021
Facial Cues and Context Clues: Autistic Children May Overly Rely on Facial Expressions to Judge Emotion
Researchers find that autistic children identify emotions through facial expressions, and so misidentify hidden or maske ...
OCT 15, 2021
Health & Medicine
Over Half of Patients Infected in the Pandemic Experience 'Long COVID'
OCT 15, 2021
Over Half of Patients Infected in the Pandemic Experience 'Long COVID'
About 236 million people are known to have been infected with SARS-CoV-2, the virus that causes COVD-19. Researchers hav ...
OCT 29, 2021
Health & Medicine
Can Playing Tetris Help Patients with PTSD?
OCT 29, 2021
Can Playing Tetris Help Patients with PTSD?
Intrusive memories are one of the most harmful symptoms of Post-Traumatic Stress Disorder, or PTSD. Intrusive thoughts a ...
OCT 30, 2021
Health & Medicine
Human Brains React Fastest to the Smell of Danger
OCT 30, 2021
Human Brains React Fastest to the Smell of Danger
The ability to detect odors is important to most organisms' survival; they have to be able to find food or mates, fo ...
NOV 18, 2021
Immunology
Could Maternal Antibodies Contribute to Autism Development?
NOV 18, 2021
Could Maternal Antibodies Contribute to Autism Development?
Pregnant mothers pass on oxygen and nutrients to their developing babies while shuttling away waste products from the fe ...
Loading Comments...