Research with tropical frogs shedding light on human hearing and attention disorders

Aug 02, 2011

A study conducted by Hamilton Farris, PhD, Research Assistant Professor of Neuroscience and Otorhinolaryngology at LSU Health Sciences Center New Orleans, reveals new information about the way tungara frogs in the tropical rain forest hear, sort, and process sounds which is very similar to the way humans do.

The knowledge could be applicable to communication disorders associated with and or difficulties. Dr. Michael Ryan at the University of Texas, Austin, collaborated on the study, published online in Nature Communications on August 2, 2011.

"An important component of successful communication is being able to tell which sender among many is sending the signal," explains Dr. Farris. "In auditory it's called the 'cocktail party problem.' A good example of a mistake in source assignment is when a ventriloquist performs."

To understand how the brain solves the cocktail party problem – assigning sounds to their correct source in a noisy or multi-source environment – the researchers chose to study the tungara frog because, unlike other subject species, it easily performs this complex behavior. The way it communicates is also a research asset. Male tungara frogs produce complex calls (not just repeated notes) consisting of two components that are speech-like: the vowel-like "whine" and the consonant-like "chuck."

For female tungara frogs, assigning the distinct components of male calls to the correct source is particularly challenging because males sing in aggregations, producing overlapping calls that lead to perceptual errors just like at a cocktail party. But, it's particularly important to the mate-searching female that she can accurately distinguish the male whose call she prefers from all of the others.

Using the labs at the Smithsonian Tropical Research Institute in Panama, Drs. Farris and Ryan investigated two types of cues/parameters of the call – spatial separation and call syntax – as potential cues for proper source assignment. Interestingly, they found that the , like humans, use relative comparisons to form auditory groups that are assigned to the same source. This means that they take the available sounds and then group those that are most similar. And they are more likely to group the two components with the smallest relative differences in call parameters. This is a flexible strategy that humans use in some conditions as well.

"Thus, in noisy, complicated environments, the cognitive solution is not based on absolute stimulus rules, but one which compares all the sounds and then deduces their sources," concludes Dr. Farris. "Based on our research, we now have a better understanding of how the acoustic cues are used to solve the problem, an understanding that will guide research advances to solve communication problems associated with hearing deficits and disorders of attention."

Explore further: Research shows impact of BMR on brain size in fish

Related Stories

Sound localization at cocktail parties is easier for men

Jun 30, 2011

Differences in male and female behaviour are often subject to study. Women are known to be more verbally fluent, have better manual dexterity and are better at noticing things (like a new haircut). Men on the other hand often ...

'Virtual mates' reveal role of romance in parrot calls

Aug 03, 2010

Parrots are famed for their ability to mimic sounds and now researchers have used 'virtual mates' to discover if female parrots judge male contact calls when deciding on a mate. The research, published in ...

I am treefrog, feel me shake (w/ Video)

May 20, 2010

Using experiments involving a mechanical shaker and a robotic frog, researchers reporting online on May 20th in Current Biology have found new evidence that male red-eyed treefrogs communicate with one an ...

Recommended for you

Research shows impact of BMR on brain size in fish

17 hours ago

A commonly used term to describe nutritional needs and energy expenditure in humans – basal metabolic rate – could also be used to give insight into brain size of ocean fish, according to new research by Dr Teresa Iglesias ...

Why do animals fight members of other species?

Apr 23, 2015

Why do animals fight with members of other species? A nine-year study by UCLA biologists says the reason often has to do with "obtaining priority access to females" in the area.

Dolphins use extra energy to communicate in noisy waters

Apr 23, 2015

Dolphins that raise their voices to be heard in noisy environments expend extra energy in doing so, according to new research that for the first time measures the biological costs to marine mammals of trying ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.