G. Heinz
One of the first questions when developing the theory of waves on nerves - interference networks - was about the pulse delay of ordinary meat. Can ionic conduction in meat delay nerve-like impulses?
Therefore, in September 1992, before the thumb experiment, the very first experiment was made with a pork schnitzel. The result was as predictable as the amen in church. So I have forgotten to note this experiment until now. Apparently, interested readers have the same question when familiarizing themselves with interference networks.
Can ordinary meat delay electrical signals, or is this a special feature that only nerves can achieve? The 1992 experiment was recreated. Back then, a simple, single-channel tube oscilloscope with a cutoff frequency of 125 kHz was used. Today, a modern USB oscilloscope is used. However, the result is the same.
A square-wave generator RG1 in Fig. 1 generates a square-wave signal at 125 kHz with an amplitude of 4 volts. It creates a series of positive, rectangular pulses, each lasting 4 microseconds - shorter than any known pulse from the nervous system. This makes it possible, to make even the smallest delay visible - if it exists.
The signal is attenuated by a 100 kΩ resistor R1. The oscilloscope is connected to the square-wave generator with the blue channel, and to electrode E1 with the red channel, see Fig. 1.
On the meat (pork cutlet) in Fig. 2, a capacitance C (not shown) is placed between the test electrodes E1 and E2, creating an RC element. The meat also has a resistance R (not shown), which provides additional attenuation. The meat layer is approximately 4 cm thick.
The electrodes were made of aluminum foil, measuring 2 x 2 cm, and are attached to the underside of a transparent plastic sheet with double-sided adhesive tape at 10 cm intervals. Staples connect the leads on the top panel.
Fig. 1: Schematic of the setup. The square-wave generator RG1 is set to 125 kHz. Two channels of the oscilloscope OSZ1 are connected to the series resistor R1.
Fig. 2: Muscle meat (pork schnitzel) with electrodes attached to it
Fig. 3:Oszillogram without meat - Channels A (blue) and B (red) are both set to +/- 5 Volts, the time axis is divided in 10 µs/div
Fig. 4: Oszillogram with meat - Channel B (red) is now set to +/- 1 Volt. There is no delay between the blue and red channel.
While without the meat (Fig. 3), an RC-element is created whose dominant C originates from the measurement setup, with the meat underneath the electrodes, we see a nearly identical waveform (Fig. 4). However, with one peculiarity: The amplitude is reduced by the meat to about one-fifth. The meat represents an attenuation of approximately 0.7 Vpp to 3.4 Vpp, equal to 0.2. This results in an equivalent resistance of the meat of 100 kΩ times 0.2, equal to 20 kΩ.
Surprisingly, the signal shape changes practically not; the capacitance of the meat has almost no effect. On the contrary: With the meat, the arrangement becomes a lower impedance, and the edges (red) appear somewhat steeper in Fig. 4 compared to Fig. 3. A slight negative shift of the signal at E2 is also noticeable, which is probably caused by a rectifying effect of the aluminum foil with the meat.
Comparing the corners of red and blue signals in Fig. 4, it becomes clear that meat shows no trace of any signal delay. In meat, we are dealing with a simple RC-element, a parallel circuit of resistance R and capacitance C.
Slow neural conduction is apparently a special development of evolution, the meaning of which probably only becomes fully clear with the theory of interference networks.
If the meat would have the highest conduction velocity in the range of 100 meters per second (myelinated axons), a delay of one millisecond would be observed over a length of 10 centimeters. This is not the case.
Slow nerve conduction is apparently a special development of evolution, the meaning of which probably only becomes fully clear with the theory of interference networks.
Created 2025/05/17
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