Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How fish hear and make sounds at same time

04.07.2005


Cornell University researchers have learned how a common fish found along the West Coast can hum and hear outside sounds at the same time.


Photograph by Margaret Marchaterre, Department of Neurobiology and Behavior, Cornell University.
A male plainfin midshipman with his newly hatched embryos attached to the rocky substrate of his nest (top right). A graph of neural impulses over a period of a few milliseconds is superimposed over the photo. The yellow lines show nerve impulses that lead to vocal muscles and cue them to make noise. The sounds actually occur in the millisecond spaces between each yellow spike. As the sound takes place, the brain also sends an impulse to the fish’s ear (red spikes), which reduces sensitivity during intervals that coincide precisely with the noise. Copyright © Cornell UniversityClick



The study marks the first time that scientists have found a direct line of communication between the part of a vertebrate’s brain that controls the vocal muscle system and the part of the ear that hears sound. The researchers believe that understanding the auditory system of the plainfin midshipman fish (Porichthys notatus ) -- a 6- to 10-inch fish found along the coastline from Alaska to California -- will offer insights into how other vertebrates -- including humans -- hear.

The general pattern of connections between neurons in the auditory system is the same in all vertebrates, including mammals. While humans hear with the cochlea of the inner ear, the midshipman uses the sacculus, a part of the ear that in humans detects acceleration or linear movement.


Because the study indicates a relationship between the ear and the auditory and vocalization systems of the brain, it could help scientists understand some of the mechanisms that contribute to deafness.

"We’ve studied so many things about these fish, and I never cease to be amazed by how similar the operation of their nervous system is to that of mammals," said Andrew Bass, professor of neurobiology and behavior at Cornell, and an author of the study published in the June 22 issue of the Journal of Neuroscience. "You don’t need to study a mammal to understand what a mammal does."

The researchers found that as the fish’s brain signals vocal muscles to make sound, a number of synchronized actions take place. The ear and brain are cued to the exact timing of a self-generated sound, distinguishing it from outside sounds. Just prior to a voicing, the brain warns the ear it should become less sensitive.

When analyzed closely, the vocalizations can be broken down into a series of impulses separated in time by only milliseconds. The system is timed only to block out sound at the exact moment when the fish vocalizes, leaving the ear sensitive to outside noises during the millisecond gaps when the fish is silent. Once an impulse for vocalization ends, the brain decreases its messages to the ear, which in turn makes the ear more receptive to external sound again. In fact, for an instant following a vocalization, the ear may actually become more sensitive than it was prior to the voicing.

By better understanding these complex systems, the study offers new avenues for researchers to explore the causes of human deafness.

"Hearing loss is a major pathology that humans deal with," said Bass. "And we don’t understand that mechanism very well. Observing what these neurons do may offer insights into what leads to hearing deficits."

Only a few fish vocalize, but male plainfin midshipman fish hum to attract a mate or grunt when stressed. When courting, the midshipman hums continuously for up to two hours to attract a female, who may deposit up to 200 eggs, which the male fertilizes. The next night, the male hums again to attract a new mate. In one season, a successful male may end up fertilizing several thousand eggs.

During mating season, houseboat owners in San Francisco Bay have complained that their homes vibrate from the humming fish, which sound like a high-speed motor running underwater.

Co-author Matthew Weeg received his doctorate from Cornell and worked in Andrew Bass’s laboratory before recently becoming a lecturer at Colorado State University. The other co-author, Bruce Land, is a senior research associate in Cornell’s Department of Neurobiology and Behavior.

Krishna Ramanujan | EurekAlert!
Further information:
http://www.news.cornell.edu/stories/July05/Bass.kr.html

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>