• Nicholas GrazianeEmail author
  • Yan Dong
Part of the Neuromethods book series (NM, volume 112)


Synaptic transmission often occurs at the current level of pico-amperes. Because of the microscopic currents generated, they must be collected and amplified before they can be examined and analyzed. This job is done by the micro-amplifier. The amplifier directly connects to the electrode acquiring electrical signals from the targeted cell or brain regions. Thanks to advances in semiconducting technology, most amplifiers are light-weight, but extremely efficient in achieving stable, low-noise recordings. Combined with user-friendly software, operating the amplifier requires little effort. We have witnessed several occasions that without any prior experience, an undergraduate student successfully recorded synaptic transmission and collected useful data in a well-tuned setup. Nonetheless, these user-friendly features of the hardware and software are also risky because investigators need to know far less about the underlying mechanisms of their operation before they can start collecting data. This can lead to erroneous results. Here we summarize several basic properties of the preamplifier, with the hope that by knowing these properties, some obvious mistakes can be avoided.

Key words

Data acquisition frequency Gain Compensation Leak subtraction Filtering Troubleshooting noise 


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Neuroscience DepartmentUniversity of PittsburghPittsburghUSA

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