Electrode implant for the brain

[wittgenst3in]

I was reading an article from New Scientist here in which they show a new type of electrode to be fitted to the skull of patients in order to measure the potentials of various neurons. Trouble is that as the neurons grow and change over time the connection is lost. Hence they have designed an electrode that has some form of servomechanism that automatically moves to track the signal strength.

Seems quite straightforward, but my question is this: Dosen't the mounting shown in the photo assume that the brain is fixed to the inside of the skull? I thought that this wasn't the case.

I remember hearing that in a car accident where the head was accellerated backwards, the brain would actually fly to the back of the skull cavity (rather than the front as we might naively expect) because the fluid rushes forwards. (Cf. the experiment with a helium baloon in a moving vehicle in which the baloon moves to the front of the car when you drive away, whilst passengers are pressed to the back.)

How much freedom does the brain have inside the skull? They say there's a mechanism to retract to prevent puncture, but it dosen't seem to be talking about movement, only preventing driving too deep. I'd hate to think that someone could sustain a blow to the head only to have the electrode cut a swathe out of the grey matter.

 

[Xeriar]

I remember that video too... and as far as I know you're right. The brain case is under pretty high pressure which stabalizes it some, I think the bouncing effect only occurs in rapid acceleration/deceleration and not just blows to the head.

Though I imagine this will get altered into something crawling over the brain tissue itself, where it contacts with receiver plates on the skull that it otherwise glides across.