Speech, understanding and comprehension are cognitive processes – they happen in the brain. When hearing is compromised, the signal that the brain is accustomed to processing is different and it takes more effort to fill in the blanks. The extra effort required to process sound can have a negative impact on other cognitive activities, including memory and the ability to engage in conversation.
Current research is digging deeper to fully understand the relationship between cognition and hearing loss. Hearing aid manufacturers try to preserve the unique characteristics of speech when they design hearing aid circuits, attempting to keep the important details and protecting the clarity of speech.
Contemporary hearing aids that communicate with one another can help both ears work together with the brain in real time. This preserves the natural sound differences that occur at each ear. These are often referred to as spatial cues.
Spatial cues allow listeners to determine the location of sounds in space (i.e., knowing where sounds originate) thus allowing the listener to know where to focus their attention. Further, some of these cues have been shown to allow people with normal hearing to better understand speech in more difficult listening situations. This brain function is referred to as spatial processing and is generally compromised in people with hearing loss.
Spatial processing is extraordinarily important. People with normal hearing and normal cognitive ability can realize an advantage as the speech source and/or noise source move around the listener. Unfortunately, people with hearing loss receive less information from spatial cues and require a better signal to understand speech in noise.
Understanding speech in noise depends on many factors including differences between speech and background noise, the type and degree of hearing loss, the individual’s cognitive processing speed, attention, memory, and more. However, to understand speech in noise also includes the ability to differentiate the primary speech signal from background noise. In this case, the background noise might be referred to as the secondary speech signal. With regard to primary and secondary speech sounds, one well-known problem is the fact that human voices (the primary and secondary) overlap with regard to loudness, tonal content and timing cues. That is, we label the speech signal of interest the primary speech signal, and the other voices are generally labeled noise. Nonetheless, the ability to attend to the primary signal despite (multiple) secondary signals is part of the brain’s function to attend to speech.
Current hearing aids have sophisticated circuits that help to prioritize speech over background noise and provide varying degrees of directionality for improved hearing in noise. By giving a clear more natural sound, the effort involved in listening is reduced.
At Advanced Specialty Care, we have a dedicated team of audiologists who will work with you. Through diagnostic testing and conversations with you, one of our audiologists will not only determine what your hearing abilities are, but will work with you towards solutions for better hearing and communication. To take the first step and schedule a hearing exam, call (203) 830-4700 today. Our offices are located in Fairfield County, CT in Danbury, New Milford, Norwalk and Ridgefield.
– Dr. Arthur Tepper (With thanks to the American Academy of Audiology and Oticon Corporation)