Principles of Neuroscience Lecture 21 Looking at Neuronal Function Flashcards
What was the first technology used to look at the brain?
What was the capabilities of this technology?
The microscope
We were able to see cells, neurons
What is neuro informatics and give some of the fields that it combines
It is the integration of many sub fields of neuroscience
Neuro chemistry Structure Function Morphology Location Electricity Ontogeny Homology
What did Brodmann do?
He created a map of the brain, differentiating between areas with different neurons
Describe the difference between magnifications and resolution
Magnification: making something bigger
Resolution: making an image clear, being able to differentiate between two dots
What did Ernst Abbé define?
He defined the limit of diffraction
There is a physical law that states that there is a point past which we can not resolve an image
What does the electron microscope allow us to do?
What are some limitations of the electron microscope?
The electron microscope allows us to resolve images of very small structures, ie we can see individual synapses
Limitations:
There is a size, smaller than which we cannot resolve the image
The process of preparing a tissue for the EM is such that the tissue is so far from living.
Give a few of the new technologies that subvert the problem of the limit of diffraction
- Using fluorophores
Eg. Tag antibodies that bind to synaptic proteins fluorescently. We can now see where the synapses on a neuron are happening - Super resolution microscopy
Eg. PALM & STORM
These technologies determine the precise location of molecules is a tissue.
We are not seeing an actual image of the molecules, but instead an indication on a map where they all are
What is temporal resolution?
Why is it important?
Give an example of it
This is how good a technology is at differentiating two events that occur in quick succession
Eg. Microelectrodes in a single neuron can detect the electrical potential changes that constitute a single action potential
Describe the function of the Patch clamp electrode tip
The hole is in the size range of a single protein (ion channel) on a cell membrane
The patch clamps forms a very tight seal on the area of membrane, and can detect the activity of a single ion channel
Describe how the patch clamp electrode tip technology has given us information about ion channels
What is the structure of an ion channel?
With this technology we can determine the excitability, as well as structure of an individual ion channel
It is a multimer with a channel just large enough for ions to flow through
Describe the interaction between spatial and temporal resolution
Different technologies have different capabilities in terms of spatial and temporal resolution
Also, the technologies have varying degrees of invasiveness