Hi,my name is Eric Morgan and this is j Schmitt,and today we're going to be talking about collecting facial emg.emg stands for electromyogram which is the recording of the electrical activity of muscles.By examining specific muscles in the face,we can determine components of the facial expression which are indicative of emotional response might not be observable by the human eye.First thing to do and collecting facial emg is the gatherer our supplies.To collect facial emg we need alcohol prep pads to clean the site,abrasive lotion and cotton tip applicators to abrade the electrode site,be sure to check the expiration date on your abrasive lotion,gauze to clean the site,adhesive callers and reusable electrodes，If you have multiple sizes of reusable electrodes at your lab ensured the correct size is present.conductive gel and syringes for filling the reusable electrode caps with the gel.again be sure to check the expiration date,and finally a meter for checking contact impedance at the skin electrode interface.You'll start by preparing the electrodes, you'll need two electrodes per muscle you plan to measure and one additional ground.We need to apply adhesive collars to the cap on the electrode which will be used to attach the leads to the subject.Collars or adhesive on both sides remove the plastic on one side.place it on the cap.the hole in the center lines up with the center of the cap，we find it useful to align the tab on the color with the wire to keep both out of the way.Next we need to fill the cap with conductive gel we use a syringe to control the flow of conduct gel as fill to the full the cap.Take the syringe with the conduct of gel.Doing this at an angle will allow the air to enter making it easier to fill.Once the syringes filled it's time to fill the electrodes,be careful not to over or under fill the cap of gel.you want to fill it until there's a small bubble of gel.emerging from the hole in the center.usually emg sites are very close to each other ,so close that the callers can touch.if the electrodes are overfilled it can result in bridging of the sites with gel which will result in unusable data.we're going to repeat this procedure for each site that were measuring plus one additional electrode for ground.what you've done this gather the rest of your supplies and we're ready for the subject to arrive.we're going to go over measurement of three muscles in the face zygomatic is zygomatic as muscle is located on the cheek.corrugator is located along the eyebrow，and the peculiar is a sphincter muscle that circles the eye.the ground electrode balances the baseline voltage between the subject and the amplifier.This keeps the signals within the measurement range of the system and reduces interference.each independent device or module needs a separate ground connection.in this case all three channels are on the same module and so only one ground is needed.I'll start by placing the electrodes to measure zygomatic.Begin by washing your hands for putting on gloves,Next clean the area with an alcohol prep pad.there's no need to rub too hard.clean the area with alcohol after breaking the skin can be painful so always do this first.well then ask my subject to pull the corner of their mouth toward their ear.watch where the muscle activation is this is the line upon which you want to place your electrodes.Asking your subject to do this it's important to refer to the motion in terms of muscles not emotions.electrode goes about half way between the corner of the mouth and the junction where the job bones meet.take a cotton tip applicator and apply a small amount of abrasive gel.and gently abrade the site by twisting it between the index finger and thumb applying light pressure to the site.I'll leave a red circle of grit on the site.need this great on the skin as will act as a place holder.now abrade the second site,about a color with lower on the same line toward the corner of the mouth.once both sides have been abraded take one of the prepared electrodes and remove the final plastic cover revealing the heat of service grid off and apply the electrode in its place。now follow the same procedure for the second site along the zygomatic his muzzle.notice that the leads are placed such that they are directed away from the eyes to minimize interference with the subject.once both electrodes have been placed twist the leads and draped them behind the subject shoulder.now that we've placed the electrodes the measures I come Atticus we need to attach the ground electrode.ground electrodes will be placed in the middle of the forehead.like before,in this site with alcohol abrade the skin place the electrode firmly on the site.It's important that check that all pairs of electrodes have sufficiently low impedance to ensure quality data collect.each side there are three pairs.electrodes along the muscle itself and each of them with the ground electrode.check impedance,take the touch roof connector on the electrode,and plug it into one of the ports on the meter.make the second electrode connector and plug it into the second port.on this particular meter I need to set it to contact measurement mode.tears should have an impedance of under five kilohm.impedance is will drop over time as the conductive gel is absorbed into the skin.if impedance is are under twenty kilohm leave them for a bit and check again later.if the impedance is much over twenty kilohm it's likely that the side was not properly a braided.electrode was not well placed.you should remove the sensors and try again,Now we will place the electrodes to measure the corrugator,assets subject to pull the corners of their eyebrows together and down toward the nose.watch where the muscles are activated along the brow line.watching the same way as I go Matic is I have placed the electrodes on the previously mentioned sites.remember that it's important to angle the electrode wires in such a way that they aren't an annoyance for the subject.at this point you need to check the impedance of the three electrode pairs associated with corrugator.The final MSL we're going to measure is the abiquiu Lars first clean this site with alcohol being careful not to get in the subject's eyes.ask the subject to look straight ahead at a stable point.Using the same method i've placed these two electrodes and checked to ensure all pairs of electrodes have sufficiently.now we need to plug the electrodes into the data acquisition hardware such as the Bionext or MindWare mobile.In this case I'm using a Bionext.I'll be electrodes into the subject harness there are colour coded pairs in the harness.am sure that each pair of electrodes associated with each site.wasn't the same color input on the subject hard.be sure to grab the electrode by the touch proof connector as the not damage the wire.black corresponds to ground.Next take the other end of the subject harness and plug it into the module being used for data recording.typically a three or four channel module.now you're ready to begin data collection.emg electrodes should immediately be washed with soap and water after each use as the electrolyte gel just during the emg collection is water soluble.I need the electrodes with alcohol will result in smearing which can build up within the electrode and speed up corrosion.recommend keeping obtain are of tap or distilled water in the lab.After each experiment,the electrode and a cup of water,the ninety minutes.Following the silk it's best to wash the electrodes with a liquid dish soap or electro cleaning spray,cotton tip applicator can be used，described the inside of the cap.After the electrodes have been thoroughly cleaned placed him out to dry it's important that the electrodes are completely dry before the next experiment.That concludes our presentation on collecting facial emg ,even more so than with other measures critical that you become proficient at applying sensors for several reasons.First preparation is complicated and it can be tricky to obtain the desired impedance measurements.Secondly subjects are going to be uncomfortable having sensors placed on their face.the better you are at it and the more practice you are and more comfortable your subject is going to be.Thanks for watching.Be sure to check out our support site for additional training materials.