PSYCH261 Chapter Notes - Chapter 5: Confocal Microscopy, Scanning Electron Microscope, Stainless Steel
1 May 2018
School
Department
Course
Professor
Methods and Strategies of Research
Experimental Ablation
Lesions studies- removal/destruction of a portion of the brain, used to see what function/process is
impairs
Creating lesions- put stainless steel wire with insulation except tip into brain, send radio frequency, this
way kills everything in that area,
Histological method- cut open the brain and stain it after experiment to verify location of the lesion
Exitonic lesions- employing excitatory amino acids to excite neuron to death, more selective
Sham lesion- completing the procedure except turn the machine on to make the actual lesion, this group
works as a control
Temporary lesions- inject local anesthetic to disrupt activity temporally
Stereotaxic surgery- brain surgery using a stereotaxic apparatus to position electrode. Very precise
Bregma- junction of sagittal and coronal sutures, reference point of surgeries
Stereotaxic atlas- drawings and pictures used for reference in surgery, contains coordinate and
measurements
Stereotaxic apparatus- device includes head holder to maintain proper position, electrode holder, and
calibrated mechanism that moves electrodes. Also used on humans during surgery
Fixature-destroys autolytic enzymes so brain remains in same form, and stops decomposition
Formalin- most common type of fixature, aq solution of formaldehyde, stops autolytic and hardens brain
Perfusion- removing blood and replacing it with another fluid, creates better histological results,
Microtone- once brain is removed and fixed, is it sliced into thin sections with a micro tone
Franz Nissel- German neurologist who discovered dye called methylene blue, only satins nissens
substance which contains RNA, DNA and nucleus proteins
Light microscopes- limited by ability to resolve small details
Transmission electron microscopes- electrons are passed through thin slice of tissue, electrons cast
shadows, provides info on structure to a few nanometers
Scanning electron microscope- less magnification than transmission, shows three dimensions,
Confocal laser scanning microscopy- can see details inside of thick tissues, can be used to see top layers
of live brain. Requires part of interest to be stained with fluorescent dye. Particular wavelength of light
is produce, it triggers fluorescene in the tissue, light passes through pinhole on screen and then is
measured
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Lesions studies- removal/destruction of a portion of the brain, used to see what function/process is impairs. Creating lesions- put stainless steel wire with insulation except tip into brain, send radio frequency, this way kills everything in that area, Histological method- cut open the brain and stain it after experiment to verify location of the lesion. Exitonic lesions- employing excitatory amino acids to excite neuron to death, more selective. Sham lesion- completing the procedure except turn the machine on to make the actual lesion, this group works as a control. Temporary lesions- inject local anesthetic to disrupt activity temporally. Stereotaxic surgery- brain surgery using a stereotaxic apparatus to position electrode. Bregma- junction of sagittal and coronal sutures, reference point of surgeries. Stereotaxic atlas- drawings and pictures used for reference in surgery, contains coordinate and measurements. Stereotaxic apparatus- device includes head holder to maintain proper position, electrode holder, and calibrated mechanism that moves electrodes.
