Basic electronics states that if it can transmit, it can also receive. See details for the question I have.?

Question

Some modern toys are now manufactured with sensors that read & respond to brain waves. As headphones can also be used as a microphone, and a microphone can be used to emit sound (though each operates less efficiently at the task for which it was _not_ designed), might it also be possible to "transmit" a signal from such a sensor that could provoke some sort of response in the brain via the same features the brain uses to broadcast brain waves?

Answer 1

While not impossible, it depends a great deal on what you mean by "transmit" a signal from such a sensor. For example, there exist ultrasonic devices that can take voice/music/sound as an input, convert that information into mechanical vibrations and, through the placement of ultransonic transducer elements on the face/skull, communicate that audio directly into the brain's auditory cortex without passing through the normal channels for hearing (the ears and auditory nerve). Now that sound information goes into the brain in one energy (waveform) but would not, in my opinion, be re-radiated out from the brain in the form of EEG signals. Or, if it did, the information would be "coded" in a much more complex way.

Hears a thought: the brain is indeed both a receiver and a transmitter. The only reason that we do not hear RF radio or TV broadcast directly, is that the brain and nervous system does not respond to sine-wave energy, but does respond to energy waveforms with very sharp rise and fall time edges (spikes and square-wave signals). Actual voice to skull information tansmission has been achieved by modifying the RF signal so that sound information is carried in pulsed microwave carrier energy.

See: Microwave and Behavior http://www.raven1.net/v2succes.htm

Answer 2

Your first assumption, if it can transmit, it can receive, is actually not correct. While some transducers, like ordinary speakers, can function both as speakers and microphones, many other types, including condenser microphone cannot function as a speaker.

Even if the device could transmit some waves, one will have to know what to transmit before it can have any meaningful effect. Since sophisticated medical device has yet to exist to do such things, it is doubtful a toy can achieve such feat.

"Brain waves" as we know it today, are very weak electrical pulses in order of hundred micro-volts to few Milli-volts. To "transmit" such waves, one would simply need a piece of wire affixed to the scull.

Answer 3

I'm reading your question and it gets a little confusing towards the end. I think that the answer is "Yes". Back in the 1970's they were really performing these transcendental type brain wave experiments, they were to put a brain wave cap on you and you could run a little electric H.O. scale train with brain waves instead of electricity.

Answer 4

I would like to answer your question but could you be more specific as to what toys your speaking of...