Scientists at Harvard Medical School have made a breakthrough in understanding how neurons in the brain communicate during the decision-making process. Through a study involving mice navigating a maze, researchers gained insights into the neural circuitry underlying choices.
Understanding Neural Circuitry in Decision-Making
( Credit to: Scitechdaily )
Scientists at Harvard Medical School have made a breakthrough in understanding how neurons in the brain communicate during the decision-making process. Through a study involving mice navigating a maze, researchers gained insights into the neural circuitry underlying choices.
( Credit to: Scitechdaily )
The study, published in the journal Nature, combined structural, functional, and behavioral analyses to explore the connections between neurons and how they support decision-making. This research marks the first time that these three approaches have been integrated to understand the neural basis of choices.
Wei-Chung Allen Lee, an associate professor of neurobiology at Harvard Medical School and co-senior author of the paper, explained that the organization of the brain to facilitate decision-making is still not well understood. By studying the neural circuitry involved in decision-making, researchers hope to uncover fundamental principles that govern how the brain processes choices.
Insights from a Maze Navigation Study
In the study, mice were tasked with making decisions in a maze to find a reward. The researchers observed that the mice's decisions activated specific groups of neurons in a sequential manner. These activations ultimately led to the suppression of neurons associated with the alternative choice.
These connections between groups of neurons play a crucial role in shaping decisions by inhibiting neural pathways related to alternative options. This mechanism helps animals maintain their chosen decision and prevent "changes of mind," according to Lee.
The collaboration between the labs of Christopher Harvey, a professor of neurobiology at Harvard Medical School, and Wei-Chung Allen Lee was instrumental in this research. Harvey's lab focuses on the behavioral and functional aspects of decision-making, while Lee's lab specializes in connectomics, mapping the connections between neurons in the brain.
Mapping Neural Dynamics in the Brain
The study primarily focused on a brain region called the posterior parietal cortex, which is responsible for processing information from multiple senses to aid in decision-making. The researchers aimed to understand the neural dynamics in this area during navigational decision-making.
Using virtual reality technology, the Harvey lab recorded neural activity as mice navigated a T-shaped maze. The Lee lab then used powerful microscopes to map the structural connections between the recorded neurons.
By analyzing the data, the researchers identified excitatory neurons, which activate other cells, and inhibitory neurons, which suppress other cells. They discovered that when a mouse made a decision to turn right, a specific set of excitatory neurons fired, subsequently activating inhibitory neurons that suppressed the activity of neurons associated with the left turn. The opposite pattern occurred when a mouse decided to turn left.
Stabilizing Decisions through Neural Circuitry
These findings suggest that the wiring of neuronal circuits helps stabilize decisions by suppressing alternative choices. Lee believes that there is likely some conservation of these mechanisms across species, but further research is needed to confirm these findings in humans.
The researchers are now interested in exploring the connections between neurons involved in decision-making in other brain regions. By uncovering additional rules of connectivity, they hope to gain a more comprehensive understanding of how the brain processes choices.
This study represents a significant step forward in unraveling the mysteries of decision-making in the brain. By integrating different approaches, researchers have shed light on the intricate neural circuitry that supports our choices. This knowledge could have implications for understanding decision-making processes in humans and potentially contribute to advancements in neuroscience and psychology.