Technique of the Week - Extracellular recording and mapping

Oscilloscope 

Used to see voltage changes 

audio amplifier

Used to hear voltage changes

Breathing and heart beat

What two things cause the brain to move, making it difficult to insert an electrode into the neuron of a living animal?

breathing

_______ causes veins to expand and pull blood our of the brain making it shrink

heart beat

______ _____ causes the bran to get larger and smaller and blood is pumped in and out

negative

The extra cellular recording of an action potential becomes more _______ when sodium enters the cell

Direction of rising phase 

What is the main difference between the intracellular and extracellular voltage recordings? 

larger

There is not as much of a “rising phase” spike during the extracellular recording because the space the sodium is coming from is _______ making the concentration change smaller

Vernon Mountcastle

Who discovered the cortical column

homunculus

As you move along the __________ new receptive fields are found

Pyramidal 

_________ cells: 

• projection neuron 

• excitatory (glutamate) 

• 70% of cortical neurons 

stellate 

_________ cell:

• interneuron

• local circuit neuron 

• Excitatory and inhibitory (Glutamate or GABA)

• 30% of cortical neurons 

1

This layer have no cell bodies, it is made of synapses, dendrites, etc. 

2 and 3

These layers send axons to and receives axons from the other cortical areas (including opposite hemisphere)

4

This layer receives axons from the thalamus

4

Layer _ is also called the input layer

5

This layer sends axons to brain stem and spinal cord 

6

This layer sends axons to the thalamus

white matter

what is under the last layer of a cortical column

6

how many numbered layers are in a cortical column