Our ears and our brains work together to help us hear.
Soundwaves from your environment are captured by the outer ear and travel down the ear canal, which leads to the eardrum. When the soundwave hits the eardrum, a vibration is created, which passes through three tiny bones within the middle ear called the malleus, incus and stapes. This vibration reaches the fluid-filled cochlea in the inner ear, which causes the fluid to move. This movement activates the tiny hair cells that line the cochlea, creating an electrical impulse. This electrical impulse travels via the auditory nerve to the brain where it is interpreted as sound.
Over the past couple decades, neuroscience research has shown that the cerebral cortex generates predictions on what will happen next, and that the neurons in charge of sensory processing encode the difference between our predictions and reality.
We review what one study has shown on this topic below.
About the Study
The study, entitled, “Abstract rules drive adaptation in the subcortical sensory pathway,” was published in the December 2020. The study was headed by Dr. Katharina von Kriegstein and conducted by other researchers at TU Dresden.
Study Methodology
For the study, researchers used functional magnetic resonance imaging (fMRI) to measure the brain responses of 19 participants who listened to a sequence of sounds. The participants were told to identify one sound that deviated from the others, then their expectations were manipulated so that they would expect the deviant sound in certain parts of the sequences.
Study Results
Predictive coding describes perception as a process of hypothesis testing. It assumes that the brain is constantly generating predictions about what we will perceive in the world, like when we are at E.P. Tom Sawyer State Park playing Glow Pickleball, and then the brain detects differences between the predictions and what actually occurs.
According to the researchers, “These results provide first unambiguous evidence of abstract processing in a subcortical sensory pathway. They indicate that the neural representation of the outside world is altered by our prior beliefs even at initial points of the processing hierarchy.”
For more information or to schedule an appointment with a hearing expert, call Heuser Hearing Institute today.