Recording and Stimulating Neural Activity
Bregma
A reference point for stereotaxic brain surgery, the point or area of the skull where the sagittal and coronal sutures joining the parietal and frontal bones come together
Excitotoxic Lesion
Destroy cell bodies in a particular region using the injection of chemicals
Radiofrequency (RF) Lesion
Destroy the cell bodies, axons and terminals in the region of the electrode by heating them
Electroencephalograms (EEGs)
Electrical brain potential recorded by placing electrodes on the scalp, great temporal resolution, poor spatial resolution
Anterograde Labeling Method
Employs chemicals that are taken up by dendrites or cell bodies and then transported through the axons toward the terminal buttons
Retrograde Labeling Method
Employs chemicals that are taken up by terminal buttons and carried backward through the axons toward cell bodies
Immunocytochemical Methods
Express proteins in brain, visible with dye, produce antibodies
Positron Emission Topography (PET)
Gives localization of a radioactive tracer (injected via IV) in a living brain, measures where receptors and axon terminals are located
Magnetic Resonance Imaging (MRI)
Hydrogen atoms start aligned with the magnetic field and get "knocked over" 90 degrees, and the rotation rate correlates to the realigning with the magnetic field, different structures have different amounts of water and therefore different relaxation rates
Fos Protein
Identifies neurons that have been recently stimulated
Stereotaxic Axis
Images that correspond to frontal sections of the brain taken at various distances
2DG Autoradiography
Measures local glucose utilization, determines locations of receptors by exposing them to a radioactive ligand solution
Microdialysis
Measures neurotransmitters that are released, subject (usually animal) is awake and engaging in activity, uses a dilute solution to pick up molecules that diffuse from the extracellular fluid, contents are frozen and analyzed
2DG PET
Measures regional metabolic brain activity
Functional Magnetic Resonance Imaging (fMRI)
Measures regional metabolism in the brain usually by difference in blood oxygen level
Diffusion Tensor Imaging (DTI)
Measures white matter pathways, doesn't give information on activity, used to determine integrity of white matter
Lesion
Process of damaging parts of the brain
Histology
Produce antibodies to any peptide or protein
Stereotaxic Surgery
Type of surgery that is used to perform a lesion, uses a stereotaxic axis
Magnetoencephalography
Recordes magnetic fields induced by neural activity, determines location of a group of neurons firing synchronously
Optogenetic Methods
Stimulates (or inhibits) neurons in the brain using light to depolarize or hyperpolarize the cells, insert algae proteins to be activated when stimulated by light
Transcranial Magnetic Stimulation
Stimulates neurons in the cerebral cortex with an electromagnet placed on the head
Electrical Stimulation
Stimulates neurons near the lip of the electrode and axons passing through the regions
Chemical Stimulation (with excitatory amino acids)
Stimulates only neurons near the tip of the cannula, not axons passing through the regions
2DG (2-deoxyglucose)
Sugar unable to be metabolized, used for autoradiography and PET
CT Scan
Used for head injury or stroke, identifies location of bleeding, can't see gyri and sulci
Macroelectrodes
Used to record electrical activity of a large number of neurons in a particular brain region, attached to scalp
Microelectrodes
Very small electrode, used to record electrical activity of individual neurons, can be permanently implanted, allows movement