Electrophysiological Recording Methods Flashcards
What is needed to enlarge small signals?
Amplifiers
What are the two main types of amplifiers?
Unipolar (1 input); Bipolar (2 inputs)
Amplifier resistance has to be ____ times higher than source resistance
10 times
What causes noise problems?
External electrical interference like power lines
What is solution to noise problem?
Faraday cage, data processing
What are the different electrophysiological recoding methods
- Spontaneous cortical activity
- Evoked potentials
- Single cell recordings
- Noninvasive techniques
Provide general overview of spontaneous cortical activity
It records rhythmic electrical activity from large populations of cortical neurons. Providing information about normal and abnormal brain function.
What are 2 examples of spontaneous cortical activity?
Electroencephalogram (EEG) and Electrocorticogram (ECoG)
What is difference between EEG and ECoG
EEG recordings are from scalp (detect seizure disorders); ECoG are directly from cortical surface (localize and operate epileptic regions)
What is the evoked potential?
Records a population response of several neurons from sensory system. Provides information about excitability state and intactness of neural pathways.
What are the 2 examples of evoked potential?
Direct Recording and Indirect Recording
What is single cell recording?
Records activity or action potentials of cells
What are 3 examples of single cell recording?
- Extracellular Recording
- Intracellular Recording
- Whole-cell patch recording
What is extracellular recording?
Recording activity of one or multiple cells. Does not damage the cell so recording can last long.
What is intracellular recording?
Record resting membrane potential, local graded potentials, and action potentials of a single cell. Can control currents or intracellular environment. Cell dies.
What are patch clamps?
Records small currents through the membrane by suctioning with a glass micropipette. Kills cell
How can patch recording be split up even further?
- Cell attached
- Inside-out patch
- Whole cell recording
- Outside-out patch
What is cell attached recording?
slight suction for single channel recording (control of outside)
What is inside-out patch?
Suction and retraction to break off piece of membrane. For single channel recording (control inside and outside)
What is whole cell recording?
Strong suction to break hole. (control inside)
What is outside-out patch?
strong suction to break hole, retract, reconnect. For single channel recording (control inside and outside)
What are non-invasive techniquse?
- voltage sensitive dye to measure potential at single cell level
- MRI and PET scan for measuring activity of large sets of neurons
