DESCRIPTION The dragonfly can capture its prey mid-air with a 95% accuracy rate. What biological equipment does the dragonfly have that allows it to do this amazing feat? To examine this very question, I will be replicating Paloma T. Gonzalez-Bellido’s 2012 PNAS paper using DIY open source tools. Gonzalez-Bellido found that there are neurons that run […]

Libet had the subjects view an oscilloscope with a dot rotating periodically in a circle, and subjects were asked to retroactively report where the dot was when they first became aware that they were about to perform the voluntary task. He could then calculate the average latency between when the subject reported awareness and when […]

It took a lot of tinkering, but I’ve finally performed the free will experiment using multiple electrodes on the scalp. The hardware setup was fairly simple. Take two more Heart/Brain shields, switch C7 for a 47µF cap on both, and stack them on top of the existing setup using headers. Make sure each shield has a […]

The next steps of the project are… 1) set up a coordinate system in Matlab so by inputing the change in degrees of the servos, I can know the change in position on the screen. 2) Using Matlab, create figures that relate the neural activity to the position and direction of the laser beam. 3) Test with dragonfly […]

In order to replicate Paloma Gonzalez-Bellido’s experiment, I need to be able to manipulate the direction and position of the laser beam. In Paloma Gonzalez- Bellido’s 2012 paper she publish these results: Gonzalez-Bellido, P. T., H. Peng, J. Yang, A. P. Georgopoulos, and R. M. Olberg. “Cozzarelli Prize Winner: Eight Pairs of Descending Visual Neurons in […]

Given the previous problems, I then started on a new set-up hopeing to 1) solve the curvature of the beam problem 2) make a more stable, cleaner set-up. The final result: What I did: I cut wood to use for a stand, and used an acrylic sheet for a base. I made the Y servo mirror much longer […]

After trials and errors, the electrophysiology setup is ready to collect usable data. I have updated the current version of the protocol and setup on the instructions tab. For housekeeping, I give each grasshopper that participates in the experiments a name in the format of [day][month][letter indicating order]. For example, a grasshopper whose DCMDs are recorded […]

I built a servo laser set-up (prototype 2) that allows me to control the movement of the laser beam across a curved screen using an X direction servo and a Y direction servo. Below is the final result of prototype 2: The problems: The hot glue on the mirrors makes the mirrors tilt at an angle, and not […]

After a long and difficult time discovering the buccal ganglia, I recommend using a microscope with at least 6-8 Watt LED bulbs or else you will struggle to find the right area. The buccal ganglia is almost bikini-shaped as shown in the previous log from Ramakrishnan et al. 2014 and is seated directly behind the […]

Now that I’ve got the ear clip unipolar EEG set up, I’m finally ready to record. I have my subject wear two headbands: one around the head like a normal sweatband and one under the chin and over C3 like in my previous experiments. I had to do a quick test to get the polarity […]

Materials: check. Grasshoppers: Check. Protocol: Check, and please do check the instructions on the main project profile for the protocol of this experiment. Next step: Setting up the experiment and take off! This is how the grasshopper spends an hour of its time for science: The iPad screen is placed on the side contralateral (opposite) to where […]

Upon reading a new paper, I have determined a new location for the electrode (when I get that point in the experiment): the esophageal trunk! Ramakrishnan et al. in 2014 studied the buccal A cluster (BAC) cells that fill up the buccal ganglia, 40 in each. These cells vary in location, size, and the cluster […]