Björn Brembs
View ProfileSuspicion and progress!
Suspicion: rut may not be rut
Carsten Duch is identifying the muscles involved in operant self-learning:
It’s a start
The first few rutabaga and radish mutants have been measured and so far it looks good: standard duration yaw torque learning – the situation all three groups should learn.
Optomotor asymmetry after torque learning
Only a few more flies compared to the first week, but the difference between optomotor responses after punishing left or right torque, respectively, is starting to show:
These data suggest I should fill the groups up to a sample size beyond 20 if I want to use these data somewhere…
Optomotor effects after torque learning?
After training 14 flies it looks as if the new setup is working as it should:
Looking at the optomotor traces more closely now that (a) we know that motor neurons are the only site of plasticity and (b) we routinely record optomotor behavior after training, something very interesting appeared when comparing flies that have been trained on one turning direction with flies trained on the other side:
Flies trained to avoid right turning show reduced optomotor response to the right and vice versa! The weaker effect for ‘left’ may be due to the weaker learning in this group?
Anyway, I have never seen this and find it quite exciting!
Machine works, flies are not learning
The old software is installed with the new hardware and I’ll be testing the new software in parallel to experiments with the old software. Technically, everything seems to be working now, but the first six flies I tested did not show learning after training:
However, avoidance looks fairly ok, only the last training period gives away that something still isn’t quite the way it should be:
So I’ll go ahead and train a new batch of flies this week. I’ll focus on training/avoidance and make sure it is perfect, before I shorten the training.
NWG Poster on MBON-02 regulating habit formation
If you missed it at the Göttingen NWG meeting, you can download our poster from here:
Numerosity in Buridan’s
Last week, high-school student Marie Grünleitner tested wild type and blind flies in a modified Buridan’s paradigm. Instead of just two stripes, she put four stripes onto the arena walls: one stripe on one side and three stripes on the other. This experiment was inspired by a poster at FENS22 which is summarized in this preprint. She tested 15 flies in each group. She found that wild type flies prefer the threes stripes (up in the figures) while blind flies stay mostly anywhere at the edge of the platform.
Wild type flies:
NorpA blind flies:
I will use the other software from the authors in Paris to see if it runs on our data and what results these evaluations will yield.
Course
https://docs.google.com/spreadsheets/d/1kK-fg84ze-eEPgcxc1-ABjI4WqPdtKlfucU9zZ5TLt8/edit?usp=sharing
New batch of ATR wrecks screen results?
At the beginning of last week, the flies in the optogenetics rescreen seemed to behave very different compared to all the weeks before: groups that kept the lights on now switched it off and vice versa. There was also some of that in the control flies, but to a lesser extent. This is what the last training PIs looked like for the seven groups before last week:
The data from last week then looked like this:
Especially the two groups that did receive ATR reversed their previous screen results. Potentially, reduced concentration of ATR may have reduced the effect of light which may have led to the reversal of the effects.