Human Finger Twitch Experiment Using Finger Twitch Transducer

Transcription

1 Updated BSL PRO Lessn H06: Human Finger Twitch Experiment Using Finger Twitch Transducer This PRO lessn describes hardware and sftware setup f the BSL PRO System t recrd and measure the finger twitch frm a human subject. Objectives 1. T recrd the respnse generated frm the twitch f a finger. 2. T measure the stimulus frequency required t induce fatigue. Equipment BIOPAC Stimulatr (BSLSTMB fr MP35 r BSLSTMA fr MP30) BIOPAC Finger Twitch Transducer (SS61L) If yu dn t have the SS61L, yu can use the SS12LA Frce Transducer. See Finger Twitch Using Frce Transducer fr details. BIOPAC Human-safe Stimulating electrde (HSTM01) Electrde gel (GEL1) Adhesive tape (TAPE1) Cmputer running Windws XP r Mac OS X Bipac Student Lab PRO sftware BIOPAC Data Acquisitin Unit (MP35/MP30) Page 1 f 5

2 Setup Hardware 1. Plug the BSLSTM Trigger cable int the Analg Out prt n the back f the MP3X unit. 2. Plug the BSLSTM Reference Output cnnectr int CH 2 f the MP3X unit. 3. Plug the SS61L Finger Twitch transducer int CH 1 n the MP3X unit 4. Plug the HSTM01 human-safe stimulating electrde int the Stimulus Output prt n the frnt f the BSLSTM Stimulatr. Be sure t psitin the small metal knb n the unit in the metal grve f the BNC cnnectr and rtate clckwise t lck int place. 5. Set the vltage Level and Range. On the BSLSTMB, turn the Level knb cunterclckwise until it stps and turn the key t the left t set the Range at 100V. 6. Set the Reference switch t Fixed (15ms). 7. Turn the BSLSTM Stimulatr n. 8. Turn the MP3X data acquisitin unit n. Page 2 f 5

3 Sftware 1. Turn n the cmputer. 2. Launch the BSL PRO 3.7 sftware n the hst cmputer. The prgram shuld create a new Untitled1 windw. 3. Open the Finger Twitch template by chsing File > Open > chse Files f type: GraphTemplate (*GTL) > File Name: h06a.gtl A Stimulatr windw is autmatically generated; d nt clse this windw. Subject Setup 1. Attach the SS61L Finger twitch transducer t the subject. Palmar placement is recmmended. If drsal placement is required, make sure the UP label faces skin. Page 3 f 5

4 Calibratin SS61 Calibratin 1. Select MP35 > Setup Channels then click the Channel 1 wrench icn and chse Scaling. 2. Make sure the finger is pinting straight (best against a table) and click Cal1. This will be equivalent t 0 cm. 3. Have the subject bend his r her finger 5cm frm the table and click Cal2. This will be equivalent t 5 cm. 4. Click OK. HSTM01 prep 1. Have the subject rest his r her arm, palm up, n a flat surface and smear sme electrde gel n the lwer frearm. 2. Place the HSTM01 stimulating prbe lengthwise alng the wrist and have the Subject depress the red buttn t allw stimulatin. 3. Cnfirm that Pulse Rate is set t 1.00 Hz in the Stimulatr windw and then click n the ON switch. 4. Slwly increase the Level setting n the BSLSTM Stimulatr until an invluntary twitch is nted n the middle finger. A respnse usually ccurs between 20 and 40 vlts. If yu d nt see any twitching, set the Level n the stimulatr at 40 vlts and slwly mve the stimulating prbe arund the frearm while maintaining a lengthwise rientatin. 5. After lcating a pint n the frearm that generates a distinct twitch frm the middle finger, find a cmfrtable vltage setting fr the subject. 6. Click the OFF switch in the Stimulatr windw withut adjusting the Level setting n the BSLSTM Stimulatr. 7. Attach the SS61L Finger Twitch Transducer t the middle finger. Page 4 f 5

5 Running the Experiments Nte This recrding is set up fr the Append mde, s when the acquisitin is stpped and then restarted, data will be added t the previus data. A marker will autmatically be inserted with a time stamp t indicate the new segment start time. T save recrded data, chse File > Save As > file type: BSL PRO files (*.ACQ) File name: (Enter Name) > Save buttn T erase all recrded data (make sure yu have saved it first), and begin frm Time 0, chse: MP menu > Setup Acquisitin > Click the Reset buttn 1. Keep the HSTM01 stimulating prbe in the same place n the frearm where the twitch was detected. 2. Press the Start buttn n the data windw. 3. Instruct Subject t: a. clse eyes; and b. relax with hand resting n a table r ther surface. 4. Click the ON switch in the Stimulatr windw. 5. Have the subject depress the red buttn n the HSTM01 t allw stimulatin. 6. Increase the stimulatin frequency in the Stimulatr windw in 1 Hz increments until the Frce data plateaus. 7. Click the OFF switch in the Stimulatr windw. The data shuld resemble the fllwing screen sht. Page 5 f 5