Mysteries of the Brain: Thinking Brain

Air Date: 06/05/2015
Source:
NBC Learn
Creator:
Tom Costello
Air/Publish Date:
06/05/2015
Event Date:
06/05/2015
Resource Type:
Science Explainer
Copyright:
NBCUniversal Media, LLC.
Copyright Date:
2015
Clip Length:
00:04:49

Through neural connections, called synapses, the brain can process and store enormous amounts of information. Neuroscientist Gary Lynch at the University of California-Irvine explains how this incredibly complex communication process allows animals to learn and remember. "Mysteries of the Brain" is produced by NBC Learn in partnership with the National Science Foundation.

Mysteries of the Brain - Thinking Brain

TOM COSTELLO, reporting:

Learning from experience - in the animal kingdom it can mean the difference between life and death.  From eagles to whales to humans, animals use the information they learn in their environment each day, changing their actions to aid in their survival.  And it's all due to one of the most mysterious organs we all possess: the brain.

GARY LYNCH (University of California, Irvine): The brain is essential to all activities, of course.  But the thing that separates it from all other organs is this incredible ability to absorb information from the world.

COSTELLO: Dr. Gary Lynch is a neuroscientist at the University of California, Irvine.  With funding from the National Science Foundation, he is researching what lies behind the brain's ability to learn and remember.

LYNCH: Every instant of the waking day you're accumulating information.

COSTELLO: To process, organize, and store all the information, the brain employs cells called neurons.  Neurons are basic to all brains, from roundworms to humans.  When a puppy sniffs out a new playmate, or a panda discovers snow, the information, in the form of electro-chemical signals, is received by the neuron's antennae-like dendrites, processed in the cell body, and then passed along through the axon to the next cell in just a fraction of a second.  In a human brain, the neuron connects to as many as 10,000 other neurons, which connect to thousands of other neurons, creating a vast communication network throughout the brain.

LYNCH: So when you think about the neuron, the big antenna and the long wire, you can begin to get the picture of the web being built.

COSTELLO: Neurons communicate with each other through a junction called a synapse, where information signals are transmitted and received.  An electrical signal, called an action potential, travels down the axon of the "talking" neuron until it reaches the axon terminal, releasing chemical neurotransmitters into a minuscule gap. Spines on the dendrites of the “listening” neuron have special protein receptors that bind with the neurotransmitters.  This complex messaging sequence is repeated by the thousands every second.

LYNCH: So just think of that.  Twenty-four hours a day throughout your life, fifty billion of these things are doing this and you get an image of the complexity.

COSTELLO: If the same signal is repeated several times, as with training or practice, more synapses are affected and synaptic communication becomes stronger.  So animals can recall which foods to eat, where to find water, and how to get home from work - everything animals learn from interaction with the environment.

LYNCH: And so your memory is becoming more and more secure because more and more neurons, more and more of the synapses have got that information.

COSTELLO: Not only can synapses get stronger, but they can also get weaker or even disappear, depending on how often the synapse is used.  Communication between neurons is altered by changes in the amount of neurotransmitter released, the number and sensitivity of the neuro-receptors, and the number and shape of dendritic spines.  This means that the brain is continually building, pruning, and reshaping the network of neurons.  In his lab, Lynch demonstrates this by passing electrical impulses through the brain of a rat.  When the signal travels through the synapse, he is able to measure and record the voltage the synapse receives.  When the signal is repeated, it generates a larger voltage, signifying a stronger synaptic connection.  Lynch explains that this is because the dendritic spines are changing shape, allowing for stronger synaptic communication.

LYNCH: When it sends that message, this spine, this dendritic receiver morphs and, if everything goes right, it will morph into a state that forever afterwards, when the message comes, it generates a bigger voltage.

COSTELLO: Much of the brain's dynamic synaptic structure still remains a mystery.  But Lynch and his team are determined to unlock the secrets of learning and memory.

Close NBC Learn

FILTERING

If you are trying to view the videos from inside a school or university, your IT admin may need to enable streaming on your network. Please see the Internet Filtering section of our Technical Requirements page.

DVDs AND OTHER COPIES

Videos on this page are not available on DVD at this time due to licensing restrictions on the footage.

DOWNLOADING VIDEOS

Subscribers to NBC Learn may download videos and play them back without an internet connection. Please click here to find out more about subscribing or to sign up for a FREE trial (download not included in free trial).

Still have questions?
Click here to send us an email.

Close NBC Learn

INTERNATIONAL VISITORS

The Science of the Olympic Winter Games videos are only available to visitors inside the United States due to licensing restrictions on the Olympics footage used in the videos.

FILTERING

If you are trying to view the videos from inside a school or university, your IT admin may need to enable streaming on your network. Please see the Internet Filtering section of our Technical Requirements page.

DVDs AND OTHER COPIES

The Science of the Olympic Winter Games is not available on DVD at this time due to licensing restrictions on on Olympic footage.

DOWNLOADING VIDEOS

Subscribers to NBC Learn may download videos and play them back without an internet connection. Please click here to find out more about subscribing or to sign up for a FREE trial (download not included in free trial).

Still have questions?
Click here to send us an email.

Close NBC Learn

Choose your product

NBC Learn K-12 product site
NBC Learn Higher Ed product site

For NBC Learn in Blackboard™ please log in to your institution's Blackboard™ web site and click "Browse NBC Learn"

Close NBC Learn

If you have received a new user registration code from your institution, click your product below and use the "Register now" link to sign up for a personal account.

NBC Learn K-12 product site
NBC Learn Higher Ed product site

For further assistance, please contact our NBC Learn Support Team and we'll be happy to assist you.

Start Your Free
day
Day Trial!