Paddlefish sensors tuned to detect signals from zooplankton prey

Jan 05, 2012

Neurons fire in a synchronized bursting pattern in response to robust signals indicating nearby food.

In 1997, scientists at the Center for Neurodynamics at the University of Missouri - St. Louis demonstrated that special sensors covering the elongated snout of paddlefish are electroreceptors that help the fish detect by responding to the weak voltage gradients that swimming zooplankton create in the surrounding water. Now some of the same researchers have found that the electroreceptors contain oscillators, which generate rhythmical firing of electrosensory neurons. The oscillators allow the electroreceptors to create a dynamical code to most effectively respond to emitted naturally by zooplankton.

The results are presented in a paper appearing in the AIP's journal Chaos.

To test the response of paddlefish electroreceptors to different , the researchers recorded signals from electrosensory neurons of live fish, while applying weak electric fields to the water in the form of computer-generated artificial stimuli or signals obtained previously from swimming zooplankton.

The team then analyzed the power contained in different frequency ranges for the noisy input signals and the corresponding electroreceptor responses, and compared the two. In addition to finding that the paddlefish best encode the signals emitted by zooplankton, the team also found that as the strength of the was raised, the firing of the fish's sensory neurons transitioned from a steady beat to a noisy pattern of intermittent bursts.

This bursting pattern became synchronized across different groups of electroreceptors, increasing the likelihood of the signal reaching higher-order neurons. This provides a plausible mechanism to explain how reliable information about the nearness of prey is transferred to the fish's brain, the researchers write.

Explore further: Professor takes madness out of the month

More information: "Sensory Coding in Oscillatory Electroreceptors of Paddlefish" is published in Chaos: An Interdisciplinary Journal of Nonlinear Science.

Provided by American Institute of Physics

not rated yet
add to favorites email to friend print save as pdf

Related Stories

Scientists trace origin of shark’s electric sense

Feb 06, 2006

Sharks are known for their almost uncanny ability to detect electrical signals while hunting and navigating. Now researchers have traced the origin of those electrosensory powers to the same type of embryonic ...

Bursting neurons follow the same beat, sometimes

Sep 12, 2011

A simplified mathematical model of the brain's neural circuitry shows that repetitious, overlapped firing of neurons can lead to the waves of overly synchronized brain activity that may cause the halting movements that are ...

Scientists discover how best to excite brain cells

Jul 08, 2011

(Medical Xpress) -- Oh, the challenges of being a neuron, responsible for essential things like muscle contraction, gland secretion and sensitivity to touch, sound and light, yet constantly bombarded with signals from here, ...

Recommended for you

New Hampshire bill requires cursive, multiplication tables

10 hours ago

As schools adopt new education standards and rely more on computers in the classroom, a group of New Hampshire senators want to make sure the basics of learning cursive and multiplication tables don't get left behind.

Eastern Oregon dig uncovers ancient stone tool

10 hours ago

Archaeologists have uncovered a stone tool at an ancient rock shelter in the high desert of eastern Oregon that could turn out to be older than any known site of human occupation in western North America.

Professor takes madness out of the month

14 hours ago

With the NCAA Men's and Women's Basketballl Tournaments tipping off soon, brackets and bubble-busters are reaching a fever pitch. Dr. Jay Coleman, the Richard deRaismes Kip Professor of Operations Management and Quantitative ...

Seven strategies to advance women in science

16 hours ago

Despite the progress made by women in science, engineering, and medicine, a glance at most university directories or pharmaceutical executive committees tells the more complex story. Women in science can ...

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.