The Role of Priors in Hallucinatory Perception in Parkinson's Disease

Understanding why hallucinations happen in Parkinson's disease is crucial for improving the daily lives and care of those affected. Hallucinations are common non-movement symptoms in Parkinson's that can significantly impact how people function, increase the burden on caregivers, and may signal faster cognitive decline.

Research shows that what one perceives isn't just based on what senses pick up-it's also shaped by expectations and past experiences. Sometimes, over-relying on these expectations can lead to hallucinations. However, it's still unclear whether this explains why some people with Parkinson's experience hallucinations while others don't.

In cognitive science, one way to study hallucinations is by showing people repeated trials where a stimulus is either barely visible or not present at all. The number of times someone reports seeing something when nothing is actually there (called "false alarms") has been linked to the likelihood of experiencing hallucinations in everyday life.

To explore this further, researchers use cues that hint at whether a stimulus is likely to appear. Studies have shown that healthy individuals use these cues to guide their perception. Some research even suggests that people with Parkinson's might rely on these cues more strongly, but this hasn't been directly connected to hallucinations yet.

This study aims to test whether these cues-by shaping expectations-affect the rate of false alarms more in Parkinson's patients who experience hallucinations compared to those who don't. By understanding why false alarms happen, deeper insights will be gained into visual hallucinations, as well as improved early detection, and ultimately enhanced care.

To better understand the brain mechanisms involved, brain activity will be recorded from patients who have deep-brain stimulation electrodes that allow investigators to measure neural signals in a specific brain area called the subthalamic nucleus. This could help uncover how the brain processes these expectations and perceptions.

• Comparison of False Alarm Rates Between Parkinson's Patients Without Hallucinations and Healthy Volunteers [Срок оценки: Baseline]
• Impact of Prior Expectations on Perceptual Confidence in Parkinson's Disease Patients With and Without Visual Hallucinations [Срок оценки: Baseline]
• Neuropsychological Profile Differences Between Parkinson's Patients With and Without Hallucinations [Срок оценки: Baseline]
• Beta Power Differences in the Subthalamic Nucleus During False Alarms in Parkinson's Patients With Deep Brain Stimulation [Срок оценки: Baseline]