A recent study challenges previous assumptions about the significance of the superior colliculus, a small pea-sized region in the human brain, suggesting it plays a more crucial role than previously thought. The research, published in eLife by scientists from the Netherlands Institute for Neuroscience, sheds light on the enduring importance of the superior colliculus throughout evolution.
The researchers aimed to delve into the ability of animals, including humans, to distinguish objects from their surroundings, a phenomenon that has intrigued scientists. While the involvement of the visual cortex in this process is acknowledged, some animals either lack or have an underdeveloped visual cortex.
Building on previous studies indicating a potential role for the superior colliculus, the researchers conducted experiments using mice. Using optogenetics, they temporarily deactivated the superior colliculus to observe its impact.
Neuroscientist Alexander Heimel from the Netherlands Institute for Neuroscience explained, “In this study, we switched off the superior colliculus using optogenetics to see what effect that would have.”
The results revealed that the superior colliculus, alongside the visual cortex, plays a critical role in how mice perceive their immediate surroundings. Disabling this tiny brain region significantly impaired the mice’s ability to detect objects.
As the mice interacted with objects, the researchers observed increased brain activity in the superior colliculus. Eye tracking and brain recordings demonstrated heightened activity in the superior colliculus, irrespective of the complexity of the task.
“Our measurements also showed that information about the visual task is present in the superior colliculus and that this information is less present the moment a mouse makes a mistake,” noted Heimel.
The study emphasized the similarities between mouse brains and human brains, particularly in the parallel pathway involving the visual cortex and the superior colliculus.
“Our research shows that the superior colliculus might be responsible for this and may therefore be doing more than we thought,” concluded Heimel.