Brain's superior colliculus rotates to focus on sounds
Researchers have discovered that a part of the brain physically swivels to help focus on sounds coming from different directions. This finding, based on experiments in mice, reveals a new mechanism for auditory attention similar to how eyes move for vision. The study was led by scientists at University College London and published in Nature.
In a breakthrough study, neuroscientists have uncovered that the superior colliculus, a structure in the midbrain, can rotate to direct attention toward sounds originating from various directions. This physical movement enhances the brain's ability to localize auditory stimuli in three-dimensional space, much like the swiveling of eyes to focus on visual cues.
The research, conducted by Jun Yao and colleagues at University College London, involved high-resolution imaging of mouse brains. They observed that when mice responded to sounds played from different angles, the superior colliculus would tilt and rotate accordingly. "It's as if the brain has its own little head that turns to 'look' at sounds," Yao explained in the study.
This discovery builds on previous knowledge of the superior colliculus's role in integrating sensory information for orienting behavior. Traditionally, auditory attention was thought to rely primarily on neural signaling without physical movement. However, the experiments demonstrated measurable rotations of up to several degrees, correlating directly with sound location.
The findings were detailed in a paper published in Nature on October 23, 2024. The team used advanced techniques like two-photon microscopy to track these movements in real time during auditory tasks. No such rotations were observed in control conditions without sound stimuli, confirming the link to auditory processing.
Implications of this research extend to understanding sensory integration in mammals, including humans. It could inform treatments for hearing disorders or attention deficits where spatial awareness is impaired. The study highlights the superior colliculus's evolutionary adaptation for survival, aiding quick responses to environmental sounds like predator noises or calls.
While the experiments were limited to mice, the conserved structure of the superior colliculus across species suggests potential parallels in human brains. Future research may explore these dynamics using non-invasive imaging in primates or humans.