Neural pathways reveal a push-pull system for coordinating goal-directed behavior in mice

Most of the tasks that humans complete daily entail carefully coordinating movements and tracking progress made toward a desired goal. Past studies have highlighted the role of the basal ganglia (BG), a set of interconnected structures deep within the brain, in the selection, control and initiation of voluntary movements.

While the contribution of the BG in voluntary actions is now well documented, the processes by which it organizes goal-directed behavioral sequences have not yet been clearly elucidated. Better understanding these processes could be highly valuable, as it could also shed light on the neural signatures of specific neurological or motor disorders associated with difficulties in planning complex goal-directed actions.

Researchers at Duke University School of Medicine and Duke University recently set out to further investigate how the BG allows mice to steer their actions when trying to achieve a specific goal. Their findings, published in Nature Neuroscience, led to the identification of specific neuron populations in the BG that appear to work together to guide behavior and track progress made toward a goal, both in terms of the movements that need to be performed and how many actions are required.

Exploring the brain pathways shaping goal-directed actions

To investigate the neural underpinnings of goal-directed behavior, the researchers developed a new behavioral task. This task required mice to press a tiny lever a specific number of times, which allowed them to receive a food reward.

While the mice completed this task, the researchers recorded both their movements and tracked their progress in performing the required lever-press count. During different experimental trials, the team activated two different types of neurons in the striatum (i.e., the main input region of the BG) using optogenetic techniques.

Optogenetic techniques are experimental tools that allow scientists to control the activity of specific genetically modified cells using light. The two types of neurons they investigated are known as direct-pathway spiny projection neurons (dSPNs) and indirect-pathway spiny projection neurons (iSPNs).

“Using a novel operant counting task, we trained mice to perform a specific number of lever presses to obtain a reward, enabling quantification of continuous kinematics and discrete actions,” wrote Isabella P. Fallon, Marina Roshchina and their colleagues in their paper. “Stimulation of direct pathway and indirect pathway neurons (dSPNs and iSPNs) exert bidirectional and dissociable influences on both movement steering and press count: activation of dSPNs steers mice contraversively and extends press sequences, whereas activation of iSPNs steers mice ipsiversively and prematurely terminates press sequences.”

Essentially, Fallon, Roshchina and their colleagues found that activating dSPNs and iSPNs affected the mice’s behavior in opposite ways. Activating dSPNs resulted in the mice pressing the lever for longer, while activating iSPNs prompted the animals to stop pressing the lever before they had completed their goal and received the reward.

“Calcium imaging reveals dSPNs and iSPNs that tracked physical approach or count progress, with ramping activity patterns consistent with accumulation and discharge dynamics,” wrote the authors. “The difference between dSPN and iSPN population activity scales with proximity to spatial and numerical goals. These findings show that the BG implement a push–pull controller to integrate kinematics and action counting to steer progress toward goals.”

Toward an improved understanding of some neurological disorders

The results of the experiments carried out by Fallon, Roshchina and their colleagues offer valuable new insight into how neurons in the BG guide the actions of mice and monitor progress toward a given goal. They specifically highlight the complementary role of two key neuron populations in the BG, showing that they contribute to the tracking of the action sequences required to meet an objective.

If they are validated in humans, these findings could potentially help better understand the underpinnings of some conditions characterized by difficulties in controlling movements or planning goal-directed action sequences. Eventually, they may also inform the treatment of these conditions.

Who’s behind this story?

Ingrid Fadelli

Freelance journalist with BSc Psychology and MA International Journalism. Covers AI, robotics, neuroscience, and astrophysics since 2018.

Full profile →

Lisa Lock

BA art history, MA material culture. Former museum editor, paramedic, and transplant coordinator. Editing for Science X since 2021.

Full profile →

Robert Egan

Bachelor’s in mathematical biology, Master’s in creative writing. Well-traveled with unique perspectives on science and language.

Full profile →

© 2026 Science X Network