3 ms·
The big challenge for non-invasive BCI is that most interesting information content in the brain (e.g. speech) is encoded in high frequency firing activity, and
by tbenst 5y ago
The big challenge for non-invasive BCI is that most interesting information content in the brain (e.g. speech) is encoded in high frequency firing activity, and the skull acts as a low-pass filter.
- anonymouse008 5y agoThis is brilliance in a sentence - best of luck in your pursuits.
- Johnythree 5y agoThere are no high frequency signals in the brain. It's all relatively slow electro-chemical reactions. There are however a huge number of slow signals running in parallel. In total these would add up to a huge bandwidth if constrained on a single channel. To put it another way, the scull is almost entirely resistive. And you can't make a low-pass-filter with just resistors.
- tbenst 5y agoI’m using high frequency in a domain specific way here: neuroscientists consider gamma (30-100Hz) to be high (temporal)frequency for action potential activity. But I wasn’t just referring to temporal filtering—the skull acts as a low-pass spatial filter, too [1]. [1] https://pubmed.ncbi.nlm.nih.gov/8813415/ https://pubmed.ncbi.nlm.nih.gov/8813415/