Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Surprisingly complex behaviors appear to be ’hard-wired’ in the primate brain

16.03.2005


When you grab a piece of food and put it in your mouth, when you smile in response to the smile of a passerby or squint and grimace in anger, the complex pattern of movements that you make may be hard-wired into your brain.

Scientists have long known that many of the behaviors of lower organisms are innate. In the insect world, for example, instinctive behaviors predominate. Birds have a larger repertoire of fixed behaviors than dogs. In primates, voluntary or learned behavior predominates, so neuroscientists have assumed that the hard-wiring in primate brains is limited to simple movements and complex behaviors are all learned. Now, however, studies are finding that a number of surprisingly complex behaviors appear to be built into the brains of primates as well.

These are "biologically significant" behaviors that appear likely to improve the primate’s ability to survive and reproduce. They include aggressive facial patterns, defensive forelimb movements, and hand-to-mouth and reaching-and-grasping movements.



Vanderbilt researchers, writing this week in the Proceedings of the National Academy of Sciences Online Early Edition, report that they can elicit these complex behaviors by stimulating specific areas in the brain of a small nocturnal primate called the Galago or bush baby (Otolemur garnetti). Their results provide significant new support for the proposition that all primate brains, including our own, contain such a repertoire of innate complex behaviors.

"We have now seen this feature in the brain of an Old World monkey and New World prosimian. The fact that it appears in the brains of two such divergent primates suggests that this form of organization evolved very early in the development of primates. That, in turn, suggests that it is characteristic of all primate brains, including the human brain," says Jon Kaas, the head of the research group, Distinguished Professor of Psychology at Vanderbilt University and investigator at the Vanderbilt Kennedy Center for Research on Human Development.

"These results explain why certain behaviors – such as defensive and aggressive movements, smiling and grasping food – are so similar around the world. It is because the instructions for these movements are built-in and not learned," he adds.

Over the last 20 years, neuroscientists have identified an area called the primary motor cortex, which, when stimulated, triggers simple muscle movements. The fact that they were able to produce only motions by single muscles and other simple movements reinforced the idea that only simple movements were hard-wired into primate brain circuitry.

Then, last year Michael Graziano at Princeton University pointed out that previous stimulation experiments in the motor cortex – the area that controls bodily motions – had been done using very short electrical pulses that last less than a half-second. He further suggested that longer pulses might stimulate more complicated motions. Working with alert macaques, he and his colleagues found that applying such long-duration signals did in fact elicit several of these complex behaviors, much as they had predicted.

Kaas and his colleagues, research assistant professor Iwona Stepniewska and doctoral student Pei-Chun Fang, decided to follow the Princeton researchers’ lead and try long-duration stimuli in the simpler brain of the Galago. When they did, they also found that this type of stimuli triggered complex behaviors. In fact, they were able to stimulate a larger number of complex movements than the Princeton group had reported, including aggressive facial patterns, defensive forelimb movements, and hand-to-mouth and reaching-and-grasping movements.

The Princeton researchers stimulated areas in the motor cortex. The Vanderbilt researchers found that they could also elicit these behaviors by stimulating a nearby area of the brain called the posterior parietal cortex. This area is heavily interconnected with the motor cortex and had previously been associated with transforming data from the eyes and other senses into a spatial map of the surrounding environment. The new findings reveal that this brain area also plays an important role in complex, innate behaviors.

David F. Salisbury | EurekAlert!
Further information:
http://exploration.vanderbilt.edu/news/news_hard_wired.htm
http://www.vanderbilt.edu

More articles from Life Sciences:

nachricht Warming ponds could accelerate climate change
21.02.2017 | University of Exeter

nachricht An alternative to opioids? Compound from marine snail is potent pain reliever
21.02.2017 | University of Utah

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Impacts of mass coral die-off on Indian Ocean reefs revealed

21.02.2017 | Earth Sciences

Novel breast tomosynthesis technique reduces screening recall rate

21.02.2017 | Medical Engineering

Use your Voice – and Smart Homes will “LISTEN”

21.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>