Author: Lydia Ng @ Janelia NWB hackathon User days 05/15/2019
- Zac Bowen (zacbo22@gmail.com)
- Kelson Shilling-Scrivo (kshilling-scrivo@som.umaryland.edu)
Zac and Kelson are experimentalists and their lab perform variations similar auditory coding and behavior experiments using 2-photon calcium imaging on head-fixed mice placed into a tube with access to a lick port. The mice are transgenic with a GCaMP6 reporter.
Each mouse undergoes a surgery to install a 3mm cranial window. Wide field imaging is first preformed to generate tonotopic map for the mouse by using a standardized sequence of tone stimulus.
This information is used to generate a map of all regions that are tone responsive and an approximate location of primary auditory cortex. The experimenter will use this information and further tone stimulus to best optimize the 2-photon imaging location to yield high quality data depending on the experimental question.
The lab primarily performs single plane 2-photon imaging. Multi-plane (volumetric) imaging is currently being piloted for passive experiments.
Their auditory stimulus consists of the following components:
- the fundamental frequency
- the intensity in dB of presentation
- if and how the tone is modulated (eg sinusoidal frequency or amplitude modulation)
- how it starts and stops (onset and offset ramps around 10ms)
- the start/stop of the presentation interval relative to the trial
- more complex stimulus includes, tones in noise of various types and amplitude, frequency sweep etc.
The auditory stimulus is not recorded by can be computationally reconstructed for analysis.
The experiment can be passive, where various auditory stimulus is presented and recorded.
Kelson describe a tone detection task for the purpose of generating psychometric function. A trial is bookended by 1 sec intervals of silence around a 3 sec presentation of noise. The tone is play at 2 sec after trial onset for 1 sec duration. The mouse will be rewarded with water, if they lick after the tone is played and before the start of the silence period. In a miss condition, there is a time out which delays the onset of the next trial.
In addition, a video of the eye is capture for pupil tracking. The pupil size is used as crude read out for attention/arousal state.
| Entity | Information |
|---|---|
| Species | mouse |
| Genetic Tools | transgenic line with GCaMP reporter |
| Devices | 2-photon imaging single plane and multi-plane, wide field imaging |
| Apparatus | lick port, audio speaker |
| Spatial coordinates & anatomy | wide field imaging use to locate primary auditory cortex. Optimal placement of imaging window by response to tone and/or high contrast cells |
| Stimulus | tones with different frequencies, modulation, amplititude and more complex presentation (tone in noise, frequency sweep) |
| Behavior | tone detection task, respond by licking. Time out if miss trial. |