Andreas Schroeer1, Ronny Hannemann2, Farah Corona-Strauss1, Daniel Strauss1
1Systems Neuroscience and Neurotechnology Unit, Faculty of Medicine, Saarland University & School of Engineering, htw saar, Germany
2Audiological Research Unit, WS Audiology – Sivantos GmbH, Erlangen, Germany
Recently we demonstrated that human brains retain a circuitry for orienting the pinnae during goal-directed attention to sustained speech which is reflected in sustained electrical activity of four different muscles within the vestigial auriculo-motor system.
During voluntary effortful orienting we particularly observed an upward movement (“perking”) of the pinna that was not apparent in the reflexive automatic orienting.
In the current exploratory study, we want to examine whether the observed auriculo-motor activity-pattern are dependent from the amount of listening effort needed to follow a sustained speech signal in a complex acoustic background. We asked n=13 subjects to attend one audiobook narrated by a female speaker embedded in the context of other audiobooks played (varying in pitch and number) simultaneously.
In line with our hypothesis only the activity pattern of the muscle responsible for the “perking” in voluntary direction of attention showed differences between easy and difficult conditions whereas the other auricular muscles did not show differential patterns.
Although further research is needed the results complement the knowledge about the function of the human vestigial circuitry for orienting the pinnae.