Stimulating the Neurons
Using a toothpick, gently touch the barbs (tiny hairs) on the cockroach leg. You might notice that many barbs don’t generate any spikes, but with patience, you’ll find a hair that does. When you touch the right hair, you’ll hear a burst of spikes almost instantly. This shows how quickly neurons respond to stimuli!
Now, explore more barbs. Notice that different barbs produce different spike patterns. Some have taller spikes, others shorter, and their shapes may differ. Interestingly, spikes from the same hair always look the same, highlighting an important principle: action potentials are consistent in size and shape for a single neuron. Different spikes in your recordings suggest activity from multiple neurons.