Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Inside the Brain of a Crayfish: Mellon Looks at Integration of Dissimilar Senses

04.09.2007
Voyage to the bottom of the sea, or simply look along the bottom of a clear stream and you may spy lobsters or crayfish waving their antennae. Look closer, and you will see them feeling around with their legs and flicking their antennules – the small, paired sets of miniature feelers at the top of their heads between the long antennae.

Both are used for sensing the environment. The long antennae are used for getting a physical feel of an area, such as the contours of a crevice. The smaller antennules are there to both help the creature smell for food or mates or dangerous predators and also to sense motion in the water that also could indicate the presence of food, a fling or danger. The legs also have receptors that detect chemical signatures, preferably those emanating from a nice hunk of dead fish.

“They constantly flick their antennules,” says DeForest Mellon, a University of Virginia biology professor, as he watches a Southern swamp crayfish in a bucket doing just that. “It is doing two things that are processed simultaneously in the brain as he flicks: smelling the water, and also sensing motion in the water, which can indicate the presence of food or other things of interest.

“I’m interested in understanding how these senses are combined and interpreted in the brain of these animals. My question is, how does the brain detect, integrate and use co-joined but dissimilar sensory inputs?”

... more about:
»Environment »Mellon »antennule »creature »sense

It’s much like humans tasting food by a combination of senses that detect taste, aroma, texture and how good that dish of pasta looks. It’s a complex process of brain processing that serves us well in a world of smells, textures, flavors and visual stimuli. It’s not much different with crustaceans, though their brains are much simpler, which makes them a great study model, Mellon says.

Mellon and other neurophysiology researchers commonly use crustaceans to try to gain basic understanding of the nervous systems of creatures in general, and, wherever possible, for extrapolating what they find to a basic understanding of the much more complex human brain. All animals, from single-celled amoebas to humans, use similar cellular processes to interpret their olfactory environment.

“Due to the large-sized nerve cells of invertebrates, we can conveniently and practically examine these systems that are largely the same among all creatures,” Mellon says. “And antennule flicking can serve as a practical model that helps us understand how two or more senses work together in the brain.”

Mellon has been investigating sensory systems for half a century, since his grad school days at Johns Hopkins University. He’s still learning. “We can say we know that animals use their senses to make maps of their environment that direct their behaviors,” he says.

Recently Mellon perused the research in the field – his own and that of many other scientists – of the past 45 years or so and has published a review of the literature in the August 2007 issue of The Biological Bulletin.

What he’s found is that there is still a lot not understood. “It’s fertile ground for ongoing research,” he said. “The size of an area of the brain devoted to a particular sense gives us a good idea of how an animal perceives the world. It provides insight as to how the world is interpreted by that animal.”

About 40 percent of a crustacean’s brain is devoted to the sense of smell. “This shows how important detecting odors is to the animal,” Mellon says. Crayfish and lobsters are generally solitary creatures, inhabiting an aquatic environment that is often dark, and they need that highly acute sense of smell.

Humans, by contrast, have a very small portion of the brain devoted to interpreting smells, less than 1 percent by volume. But about 30 percent of the human brain is concerned with visual processing, interpreting images from the eye, Mellon says. As social animals, humans rely heavily on sight and color for identifying food, as well as friends and foe.

“I have always been fascinated by the diversity of animal types and their equally diverse behaviors,” Mellon says. “Both are genetically based. And through often very subtle adoption of genetic variations in different animals, evolution has arrived at different solutions to common survival problems. This behavioral diversity and the variants in nervous system organization account for why I remain fascinated with biology.”

Fariss Samarrai | EurekAlert!
Further information:
http://www.virginia.edu

Further reports about: Environment Mellon antennule creature sense

More articles from Life Sciences:

nachricht Transport of molecular motors into cilia
28.03.2017 | Aarhus University

nachricht Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>