Comparator Dual Lick Port Detector

Lick sensors can be important tools in determining rodents' licking and drinking behavior during behavioral and neuroscience research. Commercially available lick sensors generally use electrical, optical, or force sensors in measuring licking and drinking behavior. However, a common problem with commercially available lick sensors is the production of significant electrical artifacts during the recording of neural signals.

Researchers at Howard Hughes Medical Institute’s Janelia Research Campus have developed a Comparator Dual Lick Port Detector to measure neural signals without the production of electrical artifacts. The detector is designed to monitor a contact-type lick port without generating electrical interference on neural signals, minimize sensation to subject animals, and allow fast detection of neural signals. The developed system modulates a signal at the lick port and analyzes the signal for changes due to attenuation (resistance change) or phase (due to capacitive change).

In “A low-cost solution to measure mouse licking in an electrophysiological setup with a standard analog-to-digital” by Abdallah Hayar, Jeri L. Bryant, John D. Boughter, and Detlef H. Heck in J Neurosci Methods (2006 June 15), a lick detection method is described that measures the potential difference caused by a rodent lick on a metal lick port using an analog-to-digital converter (ADC). The detection was robust and did not create artifacts in electrophysiological recordings. This method was tested at Janelia and found to work well. This novel system was designed to make the design cheaper and self-contained. An adjustable threshold comparator was substituted for the ADC, and the circuit was opto-isolated.

Advantages:

• Monitors a contact-type lick port without generating electrical interference on neural signals
• Enables fast detection time of less than one millisecond
• Minimizes sensations to subject animals, thereby improving signal monitoring

Applications:

• Behavioral monitoring in animal research studies
• Animal research studies related primarily to neuronal circuit research

Opportunity:

Designs are free for non-profit research here at the Flintbox link.

Commercial licenses are available by contacting innovation@janelia.hhmi.org

Created By:

Janelia Experimental Technologies (jET)

For inquiries, please reference:

Janelia 2019-053