AI Summary
The text explains that electrically stimulating somatosensory afferents at a high frequency does not cause paresthesia (abnormal sensations). The study by Sagalajev et al. found that when axons are stimulated faster than their refractory period, spikes become desynchronized. This desynchronization leads to inhibition, with asynchronous spikes being more likely to be blocked by inhibition and unable to activate the cortex, resulting in the absence of paresthesia. The study highlights the importance of synchrony for sensations evoked by electrical stimulation and has implications for understanding how different stimulation patterns can affect sensory experiences.
Electrically stimulating somatosensory afferents at high frequency does not evoke paresthesia. Sagalajev et al. show that spikes desynchronize when axons are stimulated faster than their refractory period. Spikes engage inhibition regardless of their synchrony, but asynchronous spikes are preferentially blocked by inhibition and thus fail to activate cortex and cause paresthesia.