Insane in the chromatophore - Greg Gage

The setup

Musically stimulated squid skin as seen through an 8x microscope zoomed in on the dorsal side of the fin.

 

There is no doubt, everyone is intrigued by the fast colour-changing nature of squid's skin. Squids (like many other cephalapods) can quickly control pigmented cells called chromatophores to reflect light. TED fellow Greg Gage's fascination with neuroscience led him to the Marine Biological Laboratory at Woods Hole, MA this summer where he experimented on the giant axons of the Longfin inshore squid (Loligo pealei). This species has three different chromatophore colours: Brown, Red and Yellow. Each chromatophore has tiny muscles along the circumference of the cell that can contract to reveal the pigment underneath.

 

Here we see get a peak at some of Greg's tests on the squid's chromatophores using the cockroach leg stimulus protocol they have devised. They used home made DIY suction electrodes to attach to the squid's fin nerve, then connected the electrode to an iPod nano as the simulator. The iPod plays music by converting digital music to a small current that it sends to tiny magnets in the earbuds. The magnets are connected to cones that vibrate and produce sound.
 

Since this is the same electrical current that neurons use to communicate, he cut off the ear buds and instead placed the wire into the fin nerve. When the iPod sends bass frequencies (<100hz action="action" an="an" axons="axons" cause="cause" charge="charge" chromatophores="chromatophores" contract.="contract." enough="enough" fire="fire" font="font" have="have" in="in" muscles="muscles" nerves="nerves" potential.="potential." the="the" this="this" to="to" turn="turn" will="will">

 

More details of this and other super interesting but accesible neuroscience conducted by Greg and his team can be found at http://news.backyardbrains.com/2012/08/insane-in-the-chromatophores/

For a better explanation as well as a few more demos watch Greg's TED talk: http://on.ted.com/Gage.