Control of brain waves from the brain surface

June 15, 2012, CORDIS
Control of brain waves from the brain surface
Credit: Thinkstock

Whether or not a neuron transmits an electrical impulse is a function of many factors. European research is using a heady mixture of techniques – molecular, microscopy and electrophysiological – to identify the necessary input for nerve transmission in the cortex.

In the central nervous system (CNS), a nerve cell or neuron has a 'forest' of elaborate dendritic trees arising from the cell body. These literally receive many thousands of synapses (junctions that allow transmission of a signal) at positions around the tree. These inputs then are able to generate an impulse, or 'spike', known as an action potential at the initial part of the axon.

Previous research has confirmed that an activated synapse will generate an electric signal as a result of neurotransmitters released from pre-synaptic axons. Electrical recordings from the neocortex have confirmed that, in line with the cable theory prediction, that modulation of potential at the dendrite is highly distance-dependent from the cell body or soma.

The 'Information processing in distal dendrites of neocortical layer 5 pyramidal neurons' (Channelrhodopsin) project aimed to shed more light on how more distal sites in the 'tree' influence the action potential of the post-synaptic neuron. Furthermore, they investigated exactly how dendritic spikes can be generated, another issue about which there is little information so far.

Recent research has highlighted the importance of activation of N-methyl-D-aspartate (NMDA) receptors to bring about the production of a signal that will proceed to the soma and then result in a spike. There is also indirect evidence that interneurons targeting dendrites can control level of dendrite excitability.

Channelrhodopsin scientists simultaneously recorded the pre- and post-synaptic electrical recordings of identified interneurons and a special type of neuron, pyramidal cells that are primary excitation units in the mammalian cortex.

The project team first characterised the different types of inhibitory neuron deep in the cortex in layer 5 at apical tuft dendrites. The researchers then showed that a special type of inhibitory interneuron in the outer layer of the neocortex can suppress dendritic spiking in layer 5.

Project results show that a superficial inhibitory neuron can impact information processing in a specific pyramidal neuron. The research will have massive implications for neuroscience and help to unravel the integrative operations of CNS .

Explore further: A 3-D reconstructed image of neural dendritic trees using the advanced electron microscope technology

Related Stories

A 3-D reconstructed image of neural dendritic trees using the advanced electron microscope technology

September 13, 2011
Neurons in the brain play a role as an electric wire conveying an electrical signal. Because this electric wire is connected with various joints (synapse), various brain functions can occur. A neuron which has dendritic trees ...

Recommended for you

Research shows signalling mechanism in the brain shapes social aggression

October 19, 2018
Duke-NUS researchers have discovered that a growth factor protein, called brain-derived neurotrophic factor (BDNF), and its receptor, tropomyosin receptor kinase B (TrkB) affects social dominance in mice. The research has ...

Good spatial memory? You're likely to be good at identifying smells too

October 19, 2018
People who have better spatial memory are also better at identifying odors, according to a study published this week in Nature Communications. The study builds on a recent theory that the main reason that a sense of smell ...

How clutch molecules enable neuron migration

October 19, 2018
The brain can discriminate over 1 trillion odors. Once entering the nose, odor-related molecules activate olfactory neurons. Neuron signals first accumulate at the olfactory bulb before being passed on to activate the appropriate ...

Scientists discover the region of the brain that registers excitement over a preferred food option

October 19, 2018
At holiday buffets and potlucks, people make quick calculations about which dishes to try and how much to take of each. Johns Hopkins University neuroscientists have found a brain region that appears to be strongly connected ...

Gene plays critical role in noise-induced deafness

October 19, 2018
In experiments using mice, a team of UC San Francisco researchers has discovered a gene that plays an essential role in noise-induced deafness. Remarkably, by administering an experimental chemical—identified in a separate ...

Weight loss success linked with active self-control regions of the brain

October 18, 2018
New research suggests that higher-level brain functions have a major role in losing weight. In a study among 24 participants at a weight-loss clinic, those who achieved greatest success in terms of weight loss demonstrated ...

0 comments

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.