Legend has it that the first cocktail party was thrown by Mrs. Julius S. Walsh Jr. of St. Louis, Missouri, USA in May of 1917. Mrs. Walsh invited 50 guests to her house for a one-hour affair at noon on Sunday. “The party scored an instant hit,” the St. Paul Pioneer Press announced, and went on to say that within weeks, the cocktail party had become “a St. Louis institution”.
In 1953, British cognitive scientist Colin Cherry coined the term “cocktail party problem” to describe the difficulty that air traffic controllers were having understanding a single voice when many pilots were being broadcast over a single loudspeaker in airport control towers. Cherry was a pioneer in the field of auditory attention, specifically studying our ability to focus on hearing one conversation while many others are going on at the same time.
Focused hearing – what’s it all about?
Our ability to focus in on one conversation, among many others, involves several interconnected processes such as identifying the physical attributes of separate sound sources and then singling out just one of them, while keeping all other noise in the background. For the most part, our brains do a remarkable job in combining multisensory information and cognitive abilities. For example, we can relegate different spatial locations to particular voices, as well as automatically identify gender, pitch, talking speed, visual information, subject familiarity and language knowledge and fluency.
Solving the cocktail party problem is one of the greatest challenges facing providers of hearing aids, cochlear implants or other sound amplification devices. Holding a conversation over simple background noise, like air-conditioning or coffee makers, can be problematic but is achievable with hearing aids, for example, which use noise reduction algorithms to improve the Speech-to-Noise Ratio (SNR). However, trying to hear someone with simultaneous conversations going on in the background is much more difficult due to, what we professional call, “informational masking”. The meaningful component of speech makes it much more difficult to ignore than meaningless background noise. Why? Because what we are trying to block out might be louder, physically closer or even more attention-grabbing than the conversation we are currently having. How many times have we been deep in conversation just to be interrupted someone calling out our name or by hearing a baby crying?
Cocktail parties (as a metaphor for all environments in which several conversations are being held at one time) are challenging for everyone. Focusing on one speaker among many others is a difficult task that requires sophisticated auditory and cognitive abilities. For many older people, or for those suffering from hearing loss, this already challenging task becomes compounded. Such people must cope with an entire range of sensory and/or cognitive challenges influencing speech processing, in addition to the informational masking difficulties inherent in cocktail party environments. We will talk more about these populations – and how they are dealing with noisy situations – in future posts.