Understanding the brain in motion: Inside the Wilsaan Joiner Lab at UC Davis

How does your brain know where your hand is without looking, or adjusts when you pick up an object that’s heavier than expected? These everyday feats rely on the remarkable process known as sensorimotor integration. Sensorimotor integration is the integration of external sensory inputs and internally generated signals, and is the central focus of research at the Wilsaan Joiner lab. By studying both healthy individuals as well as clinical populations, the Wilsaan Joiner lab is uncovering how the brain builds a coherent sense of the body and the world, and what happens when that system breaks down (The SMI Lab, 2026).

Human behavior depends on combining both external sensory inputs and internal signals. For external, that includes things like vision, touch, or sound, whereas for internal, this includes things like predictions, intentions and proprioception (Nobre and Gresch, 2025). The Joiner lab takes these inputs and signals and investigates how the brain fuses these streams to guide perception and action, emphasizing that the brain continuously integrates both in real time. This integration has shown through research that the brain isn’t just reactive, but predictive. For instance, despite constant eye movements, we perceive a stable visual world because the brain integrates motor commands with incoming visual data. 

To study this integration process, the Joiner lab studies how people adjust movements when conditions change, learn from errors and update motor commands, and maintain stable perception of the world despite noisy or shifting environments. By using tools such as motion capture, eye tracking, robotics, and computational modeling, researchers at the Wilsaan Joiner lab can manipulate sensory inputs in individuals and observe how the brain readjusts (Quaia et al. 2010). An example of this includes the visuomotor adaptation where the brain recalibrates hand movements to match altered visual feedback. As Joiner has noted in his research, the brain can even use motor actions to help interpret sensory input, indicating that perception and action are deeply intertwined. 

A major focus of the Wilsaan Joiner lab is comparing healthy processing with impaired integration in clinical populations. The main populations the lab studies include schizophrenia and disorders of perception, amputees and altered body representation, and neurological injury and aging. 

For individuals with schizophrenia and disorders of perception, they often experience disruptions in how internal predictions align with external sensory input, which leads to the distorted perception of reality and difficulty distinguishing events, associated with schizophrenia. The lab investigates this by researching how neural pathways involved in prediction and sensory updating my be altered in these individuals and lead to the neurological symptoms (“How Do People with Psychosis See the World?”, 2026). 

For individuals who are amputees or have an altered body representation, the brain must adapt to missing or transformed sensory signals. So, the Joiner lab examines how the brain maintains a sense of the missing limb, or how sensory feedback can be integrated into prosthetic control. This work can help with the production and design of next-generation prosthetics, where artificial devices can provide sensory feedback that the brain learns to incorporate into its internal models.

Lastly, for individuals with neurological injury and aging, the lab investigates conditions such as spinal cord injury, alzheimer’s disease, and age-related changes in motor learning. The conditions often degrade the brain’s ability to integrate signals over time, which leads to slower adaptation, reduced coordination, and impaired memory for motor tasks.

So, why does this research matter? Understanding how sensory information is integrated can help researchers identify strategies to combat diseases, as well as prevent neurological degradation over time. For a clinical impact, this research can help to develop better diagnostic tools, design targeted rehabilitation strategies, and improve neuroprosthetics and assistive technologies. Besides clinical, this research can also help with technological innovation by intersecting work with robotics, brain-computer interfaces, and virtual reality environments for rehabilitation. These tools allow researchers to precisely manipulate sensory inputs and observe how the brain adapts, offering a powerful window into neural function.

In conclusion, the Wilsaan Joiner Lab offers a compelling view into how the brain constructs reality from a mix of internal predictions and external signals. By bridging studies of healthy individuals with research on disorders like schizophrenia and limb loss, the lab not only deepens our understanding of the human brain, but also moves us closer to practical solutions for restoring function when the delicate balance of signals is disrupted. 

Sources:

https://www.sciencedirect.com/science/article/pii/S0896627325004714 

https://joinermotorlab.weebly.com/ 

 https://pmc.ncbi.nlm.nih.gov/articles/PMC3610575/ 

https://studypages.com/s/how-do-people-with-psychosis-see-the-world-616988/ 

https://pmc.ncbi.nlm.nih.gov/articles/PMC12599382/