Vernier Q-S222 User manual

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Q-S222 Galvanic Skin Response (GSR) Sensor

Manufactured and Distributed by Qubit Systems Inc.

613-384-1977, [email protected]

www.qubitsystems.com

October 2015

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TableofContents



OverviewofGalvanicSkinResponse3



ComponentsforuseofQ‐S222GSRSensor4



QuickStartUpSteps4



ExperimentswiththeGSRSensor6

 RapidResponses 6

 BasalResponses 7



DataAcquisitionUsingtheLabQuestMiniInterface

 LabQuestMiniInterface8



InstallingandRunningLoggerPro39

 C404CustomSetupFiles 9

 GraphRanges,RunTimeanddataCollection 10

 DataAnalysiswithLoggerPro3 11

SpecificationsofoQ‐S222GSRSensor11

QubitSystemsWarrantyInformation 12

ReturnProcedure11



IMPORTANTNOTICE



TheGalvanicSkinResponseSensordescribedinthismanualisforeducationaland

researchuseonly.Itisnottobe

usedasaclinicalordiagnostictool.

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OverviewofGalvanicSkinRes p onse

Galvanic SkinResponse (GSR) is used as an indicator of stress in human subjects.When

stressed,subjectsperspiremore,andthis,togetherwithotherphysiologicalevents,alters

skin conductance. This change in conductance is measured by placing electrodes in

contact with the skin.This is done most conveniently by attaching electrodes to the

fingers,thoughotherbodyparts,suchasthebackoftheneck,havebeenused.Unlikein

other electrophysiological measurements,no electrode gel should be used between the

electrodesandtheskin,sincethiswouldalterorbufferskinconductivitychanges.



Short‐term stress events may be elicited in response to psychological shocks, such as

mentioningtheword“spider”toasubjectwhohasanaversiontoarachnids,orshowinga

hypodermic needle to someone with an intense dislike of injections. The responses

appear as peaks in the voltage output that occur within seconds of the stimulus being

presented. This type of response is most often looked for in polygraph (lie detector)

analysis. The response is quite small, appearing as brief peaks in the voltage output.

Typicalpeaksizesarenomorethanafewhundredmillivolts.



The basal response measures slower changes in skin conductance that occur with

changes in mood.Increased stress or excitement is indicated by a gradual increase in

voltageoutput,whereasrelaxationisseenasagradualdeclineinvoltageoutput.



With the Qubit Q‐S222 GSR sensor, two cables are attached by alligator clips to tab

electrodes on two fingers of one hand, and the conductivity of the skin between the

electrodesismeasured.Thesecondandthirdfingersorsecondandfourthfingersofone

handaremostcommonlyusedininvestigations.Theelectrodesshouldbeattachedwith

lightpressure.Thepolarityoftheelectrodesisnotimportant.The0to5Vanalogsignals

from the GSR sensor are recorded by a LabQuest Mini data interface and displayed in

LoggerProsoftwareinmetersandtimegraphs. Skinconductance

ismeasuredinunitsof

microSiemens(µS).

Thesensorhas 2analogoutputs, a high range(40 µS)and a lowrange(5µS).The5 µS

outputcanbeoffsetwithapotentiometertopermithighsensitivitymeasurementsover

theentirerangefrom0to45µS.

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



ComponentsforuseoftheQ‐S222GSRSensor



Q‐S222GSRSensor

Powersupply

A263TabElectrodes(pkg.of100)

C610LabQuestMinidataacquisitioninterface(notincluded)

C901LoggerProDataAcquisitionSoftware(notincluded)

C404CustomizedSetupFiles(notincluded)

Manual



QuickStartUpSteps



1. LoadLoggerProsoftwareontothecomputer(pg.9)

2. LoadC404customizedfiles(pg.9)

3. ConnectthepowersupplytotheQ‐S222GSR

4. Connectthe40µSdatacabletoanalogchannel1ontheLabQuestMini

5. Connectthe5µSoutputdatacabletoanalogchannel2

6. ConnecttheUSBcablebetweentheLabQuestMiniandthecomputer

7. Turnthe5µSoffsetpotentiometerontheQ‐S222off(i.e.fullyclockwise)

8. Washthesubject'shandswithsoap.Donotwipefingerswithalcoholsincethis

willdrytheskinand

alteritsconductance.Electrodegelshouldnotbeusedasit

willalsochangeskinconductance.

9. Pressthestickytabelectrodesontothefingerpadsasshowninthephotobelow.

10. AttachthealligatorclipsontheinputwiresoftheQ‐S222tothetabsofthe

electrodes.

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

11. Openthe“Q‐S222GSRSetup”filetostarttheLoggerProsoftware.Notefor

convenience,ashortcuttothisfilecanbeplacedonthedesktop.

12. ASensorconfirmationscreenwillopeninLoggerProasshownbelow."Connect"

thetwoGSRoutputsonchannels1and2oftheLabQuestMini.



Note:Theq‐S222GSRhasbeenfactorycalibratedinunitsofmicroSiemens(µS)and

doesnotrequirefurthercalibrationbytheuser.



13. Letthesubject'shandrestgentlyonthesurfaceofthebenchwiththepalm

facingdownwards.



Itisimportantthatthefingersarenotmovingduringanexperiment,sincechangesin

electrodecontactwillgreatlyaffectthesignal.



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14. Startdatacollectionbyclickingthegreenbuttonandrelaxforafewminutesuntil

thesignalsshownonthegrapharestable.

15. Adjust the offset potentiometer for the 5 µS  output so that the signal is in the

middle of the graph. Further relaxation will now be seen

 as a reduction in µS

output,andexcitationwillbeseenasanincreaseintheoutput.



Youarenowreadytostartthetreatment.



16. To test the system, start data collection, and when a stable voltage is attained,

exert a pressure with the stomach muscles while keeping

the hand still. A 

transient peak in voltage output should be observed.Alternatively, start data

collection with the subject seated in front of the computer with an assistant

standingbehindthesubject.Atatimeunanticipatedbythesubject,theassistant

shouldtouchthesubjectontheshoulder,orrunafingeragainstthebackofthe

subject’sneck.Thisshouldevokeatransientvoltagespikeirrespectiveofwhether

thesubjectfindsthestimuluspleasurableornot.



ExperimentswiththeGSRSensor



TheGSRSensormaybeusedforavarietyofinvestigationsthatinvolvethestudyof

emotionalstatesintestsubjects.Theseinclude,butarenotlimitedtothefollowing.



RapidResponses



Theseresponsesaretransitoryresponsesoccurringoverafewseconds,andwithinafew

secondsoftheonsetof thestimulus.Responsesare typicallysmall (afewhundredmV)

thereforeobservableinthelowrange(i.e.sensitive)5µStrace.Thesubject’sreactionto

variousstimulicanbeassessed.Examplesinclude:



 Touching the subject unexpectedly.The magnitude of the response should vary

depending on the type  and

location of the t ouch, as well as with the relationship

betweenthesubjectandthepersonapplyingthestimulus.



 Showing the subject objects that might provoke a response (e.g. pictures of insects,

syringes etc.).Bigger responses should be seen in subjects that are completely

unaware of the nature of the objects before the experiment starts.As the subject

becomesconditionedtotheobjectwithrepeatedexposuretheresponsemaydecline.



 Askingthesubjectquestionsofaprovocativenature.Itisrecommendedthatcaution

and sensitivity be observed with respect to the subject’s rights to privacy when

conductingsuchinvestigations.NotethattheGSRsensormeasuresemotionalstate,

andsimilarresponsescanbeobtainedforcircumstancesthatprovokeeitherpositive

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or negative emotional reactions.As with polygraph tests, numerous physiological

parameters need to be measured (not just GSR) for proper psycho physiological

assessments.



Note:Channel3isfreeontheLabQuestMiniforrecordinganotherphysiologicalsignal.

Alsomultiple Minismay beconnectedto LoggerPro to recordmoreanalog (0to 5

V) signals. Contact Qubit Systems for advice on other physiological sensors (eg.

heartrate,skintemperature,bloodpressure,EKG/EMG,respirationrate).



BasalResponses



Basalemotionalstatesdonotchangerapidlywithbriefemotionalchangessuchasthose

elicitedbyashockstimulus.Thebasalresponseismostoftenusedinbiofeedbackstudies

forthecontrolofstress,andalsotodeterminefactorsthatcauseemotionalexcitationor

relaxation over the longer term (several minutes rather than a few seconds).

Investigations may include biofeedback studies in which the subject uses relaxation

techniques to reduce stress. In this case,

the subject sets an initial voltage output to

representthe starting point, and then attempts to reducethe voltage valueconsciously

by relaxation techniques such as deep breathing, imagery or listening to music or a

calming voice. Often, a temporary increase in voltage is observed at the start of the

experiment

asthesubjectrecognizestheexperimentitselfasastress.



The basal GSRoutput can also beused to assess a subject’sresponse to various images

andcolours.Afterarelaxationphasewitheyesclosed,inwhichthebasalsignaldeclines,

the subject is asked to open the eyes and look at an image or a large card of a specific

colour. Usually, opening the eyes causes an increase in GSR signal, but the rapidity and

degreeoftheincrease isgreatlyinfluencedbytheimageorthecolourthatisimmediately

observed.Provocativeimages causearapidincrease,andbrightredtonescauseamore

rapidincreasethanmutedgreenorbluetones.



Anexampleofdataobtainedbyperiodsofrapidbreathingfollowedbyrelaxedbreathing

isshownbelow.



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

DataAcquisitionUsingtheLabQuestMiniInterface



LabQuestMiniInterface



TheLabQuestMiniinterfacehas3analogand2digitalchannels.Theinterfaceis

connectedtothecomputer(PCorMacintosh)byaUSBcable.Theinterfaceconvertsthe

analogvoltages(12bitAtoD)todigitalsignalswhicharetransmittedtothecomputervia

USBandprocessedbytheLoggerProsoftware.ThegreenLEDindicatesthatthe

LabQuestMiniisrecognizedbythedriversandisreadytocollectdata.



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

InstallingandRunningLoggerPro3



PCUsers:



(1) To start, a complete copy of Logger Pro 3 must be installed on the computer.Before

starting the installation, make sure all USB cables are disconnected from the computer.

Failuretodosomaycauseanerrorintheinstallationofthedrivers.

(2) Runtheinstallationanddonotchange thedefaultdestination directory.LoggerPro3will

beinstalledinC:/ProgramFiles/VernierSoftware/LoggerPro3.

(3) Thesetupprocesswillautomatically loadtheUSBdriversforconnectingtheLabQuestMini

orotherinterfacestothecomputer.

(4) If QuickTime 6 (or greater) is not installed on the computer, install it when prompted.

QuickTimewillallowuseofthepictureandmoviefeaturesofLoggerPro3.

(5) YouwillbepromptedtoconnecttheLabQuestMiniorotherinterfacestothecomputervia 

theUSBconnection.

(6) Click‘Finish’tocompletetheinstallationprocess.

(7) ProceedtotheC404installation(below)beforeopeningtheLoggerPro.

(8) YoucanstartloggerprodirectlyfromtheexperimentalfilethatislocatedontheC404disk

and can be transferred to user specified location and a shortcut may be created on the

desktopforeasyaccess.Doubleclickthe“Q‐S222GSRSetup”file.

(9) IfLoggerProdetectstheLabQuestMiniinterface,theLoggerProscreenwillappearwitha

star(iconforLabQuestMini)inthetopleftcorner.







(9) IfLoggerProcannotdetecttheLabQuestMiniInterface,amessagewillappear“nodevice

connected”.The LEDontheMinisshouldbe green.AredLEDindicatesthat power ison

(supplied by the computer through the USB) but there is no communication  between the

interfacesandthecomputer.In

thiscase,exitthe“Q‐S222GSRSetup”fileandunplugthe

USBcablefromthecomputer.ReconnecttheUSBcable.Allowthecompu tertorecognize

theMini(belltone)andthenre‐openthe“Q‐S222GSRSetup”file.



C404CustomSetupFiles:



QubitSystems’C404CustomSsetupFilesCDcontainsallofQubitExperimentfiles

(designedbyQubitSystems)including“Q‐S222GSRSetup”.TheExperimentfilescontain

thesetup(i.e.graphs,table,calculationsetc)forthevariousexperiments,aswellasthe

- 10 -

calibrationconstantsfortheQubitsensors.TheC404diskalsocontainsmanualsforthe

differentQubitsensorsandpackages.Thesefilescanbecopiedtouserspecifiedlocation

onthecomputerandtheexperimentalfileofinterestforthissensor–“Q‐S222GSR

Setup”shouldbeplacedinanaccessible

locationorhaveashortcutcreatedonthe

desktoptothefile.



GraphRanges,RunTimeandDataCollection



Tomodifytherangeofthexandy‐axes, click on the maximumand/orminimum  values

andtypeinthenewvalues.



If you wish to alter the maximum time

 allotted to your experiment or the rate of data

sampling,select“Experiment”,then“DataCollection”orclickontheclockiconinthetop

menu.



Type in the duration  time of your experiment in the box labelled “Duration”. Note that

the maximum value you select for the Time‐axis limits the time over which you can

collect data for a particular run.If your experiment exceeds the allotted time, select

“Experiment”,then“StoreLatestRun”.Youmaythenrestartdatacollection.Datafrom

thefirstpartofyourexperimentwillremainonthescreenasafainttraceandnewdata

willbeplottedin a bolded shade of the same colour.You can collectnumerous runs in

thisway.Eachrunwillbecollectedtoaseparatedatatable.Whenyousaveyourdata,

alloftherunswillbesavedunderthesamefilename.



- 11 -

You may also alter the "Sampling Rate" at which you collect data.The default rate for

GSRis10 samples/s.To startdata collection,clickon the“Collect” greenicon abovethe

graphs.This will change to a “Stop” red icon.Click on the “Stop” icon to stop data

collection.



DataAnalysiswithLoggerPro3



(1) Position the cursor atthe beginning of thedat a  setthat you wish to analyze, then

clickandholdwiththemouse.



(2) Drag the cursor across the data set and unclick.A greyed box will appear on the

screentoshowthedatarangetobeanalyzed.



(3) Select “Analyze”, and then choose from a wide variety of analysis options.For

example,use:



 “Examine”toscrollthroughthedatapointsatspecifictimeintervals.

 “Integral”tointegratetheselecteddata.

 “Statistics”toautomaticallyperformavarietyofstatisticalanalyses.



You can also fit curves and tangents to the selected data by choosing the appropriate

menuoption.Notetheanalysisfunctionscanalsobeaccessedfromiconsinthemenu.



SpecificationsofQ‐S222GSRSensor

 Power Supply: 9V, 560mA

 Units: (uS) uSiemens

 Resolution: 40uS Range = 0.0097uS, 5uS Range = 0.0012uS

 Accuracy: 0.5% for Full Scale, or better

 Range: 40uS and 5uS

 Offset: 5uS Range can be offset from 0 to 40 uS

 Gain: System Gain is 1980 and 15840 for 40uS and 5uS

 Cut-off Frequency fc High= 7.2 Hz

 Patient Isolation: 1500Vrms

 Size (h/w/l) cm: 2.8/6.2/9.2

 Weight (g): 200

 Materials: plastic (black)

 Warranty: 1 years



- 12 -

QubitSystemsWarrantyInformation



QUBIT warrants all its instruments to be free from defects in materials or workmanship

foraperiodofoneyearfromthedateofinvoice/shipmentfromQUBIT.

Ifatanytimewithinthiswarrantyperiodtheinstrumentdoesnotfunctionaswarranted,

returnitandQUBITwillrepairorreplaceitatnocharge.Thecustomerisresponsiblefor

shipping and insurance charges (for the full product value) to QUBIT.QUBIT is

responsibleforshippingandinsuranceonreturnoftheinstrumenttothecustomer.

Nowarrantywillapplytoanyinstrumentthathasbeen(i)modified,altered,orrepaired

bypersonsunauthorized  by QUBIT;(ii)subjected  to misuse, negligence, or accident; (iii)

connected,installed,adjusted,orusedotherwisethaninaccordancewiththeinstructions

suppliedbyQUBIT.

Thewarranty is return‐to‐baseonly, and doesnotincludeon‐siterepair chargessuch as

labour,travel,orotherexpensesassociatedwiththerepairorinstallation ofreplacement

partsatthecustomer’ssite.QUBITrepairsorreplacesthefaultyinstrumentsasquicklyas

possible; maximum time is one month. QUBIT will keep spare parts or their adequate

substitutesforaperiodofatleastfiveyears.

Returned instruments must be packaged sufficiently so as not to assume any transit

damage.Ifdamageiscausedduetoinsufficientpackaging,theinstrumentwillbetreated

asanout‐of‐warrantyrepairandchargedassuch.

QUBITalsooffersout‐of‐warrantyrepairs.Theseareusuallyreturnedtothecustomeron

acash ‐on‐deliverybasis.Wear & Tear Items are excluded from this warranty.The term

Wear & Tear denotes the damage that naturally and inevitably occurs as a result of

normal use or aging even when an item is used competently and with care and proper

maintenance.



ReturnProcedure



BeforereturninganyinstrumenttoQUBIT:

ConsulttheoperatingmanualorcontactQubittoensurethatthe instrument(s)isinfact

faultyandhasnotjustbeensetupimproperly.

ContactQUBITbeforesendinganythingback.WewillissueanRMAnumberandprovide

shipping instructions.QUBIT will  refuse any goods

 that are returned without an RMA

number,orwhicharesentinamanneroutsideofQUBIT’Sstipulations.

Ifyouhaveencounteredaprogramfailure,weneedaprintedcopyofanyfaultsyouhave

seen,including howto  reproduce them.Includethese in the returnpackage alongwith

yourmailingaddress.

IncludeacopyoftheInvoiceonwhichtheproductwasshippedtoyou.

Allreturnsmustbeshippedprepaid.Unpaidpackageswillnotbeaccepted.

IncaseofquestionscontactQUBITby

E‐mail:[email protected],

byphone:(01)‐6133841977,

orbyfax:(01)‐613384‐9118.

Vernier Q-S222 User manual

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