Positive controls in joystick optogenetics

on Tuesday, March 31st, 2020 7:40 | by

I’ve started rescreening Christian’s most consistent dopaminergic lines with the positive controls at the joystick machine, to see if everything works. These flies express the optogenetic channel Chrimson in Gr28bd and TrpA1 heat sensitive neurons, so they should use the joystick to switch the light off.

I tested three rounds of three flies each and I got the impression that it worked while I was looking at the flies. The data didn’t look that great, however:

Experimental time course of positive control flies. PIs (Y-axis) should be mostly negative.

Setting up the experiments, I noticed that the middle setup didn’t really focus the light on the head of the fly very well. This shows in the raw performance index data:

The two middle flies (row #2 and #8) have positive preferences, but never avoid the light, while nearly all other flies do avoid the light to various extents, even if they start out with a positive preference. So I deleted these two flies to see how the data would look then:

As above, only this time with the training periods averaged at the end (“Means”).

I decided that this should be good enough. I improved the middle setup to focus the light better on the fly’s head. Hopefully it will improve the PIs of the flies placed there now.

FENS poster (link for students)

on Thursday, February 14th, 2019 11:21 | by

Role of dopaminergic neurons in operant behaviour

on Friday, July 27th, 2018 3:54 | by

Positive Control: Gr28bd-G4, TrpA1-G4

Parameters: Light: intensity (500 Lux side, 1000 Lux bottom); frequency = 20Hz; Delay = 1 ms; Duration = 9.9 ms; volts = 6.4

Red lines: completed

mb025b: not selected against tubby

The Tmaze Experiments : Screen results as on 22-7-18

on Sunday, July 22nd, 2018 6:41 | by

 

Yellow 1 (Positive Control): Gr28bd-G4, TrpA1-G4

Parameters: Light: intensity (500 Lux side, 1000 Lux bottom); frequency = 20Hz; Delay = 1 ms; Duration = 9.9 ms; volts = 6.4

T-Maze experiments : screen results as on 16-07-2018

on Monday, July 16th, 2018 1:32 | by

Results of the T-maze screen analysis, both individual and combined.

Yellow 1 (Positive Control): Gr28bd-G4, TrpA1-G4

Parameters: Light: intensity (500 Lux side, 1000 Lux bottom); frequency = 20Hz; Delay = 1 ms; Duration = 9.9 ms; volts = 6.4

The T-Maze experiments : Middle analysis and Correlation plot

on Saturday, July 14th, 2018 12:06 | by

The mean ratio of the flies that stay in the middle during the experiments.

Correlation plot between the mean ratio of the flies that stay in the middle versus the Weighted PIs

Slope = 0.0053
Intercept = 0.240
R square value = -0.03834

contrary to the expectations, there seems to be no correlation .

T-Maze experiments : screen results as on 02-07-2018

on Monday, July 2nd, 2018 2:09 | by

Yellow 1 (Positive Control): Gr28bd-G4, TrpA1-G4

Parameters:
Light: intensity (500 Lux side, 1000 Lux bottom)

frequency = 20Hz

Delay = 1 ms

Duration = 9.9 ms

volts = 6.4

Tmaze Exploratory analysis : Middle Flies

on | by

plotting the mean ratio of flies which stay in the middle during experiment.

 

Yellow 1 (Positive Control):  Gr28bd-G4, TrpA1-G4

Parameters:
Light: intensity (500 Lux side, 1000 Lux bottom)

frequency = 20Hz

Delay = 1 ms

Duration = 9.9 ms

volts = 6.4

T-Maze experiments : screen results as on 25-06-2018

on Monday, June 25th, 2018 1:13 | by

Yellow 1 (Positive Control):  Gr28bd-G4, TrpA1-G4

Parameters:
Light: intensity (500 Lux side, 1000 Lux bottom)

frequency = 20Hz

Delay = 1 ms

Duration = 9.9 ms

volts = 6.4

Initial screen results

on Monday, June 18th, 2018 1:15 | by

Yellow 1 (Positive Control):  Gr28bd-G4, TrpA1-G4

Light: intensity (500 Lux side, 1000 Lux bottom), frequency (20Hz)