Validation of a Low-Cost EEG Device for Mood Induction Studies

Valida ion o a Low-Cos EEG De ice o Mood Induc ion S udies Alejand o RODRÍGUEZa,1 Bea iz REYa,b and Ma iano ALCAÑIZ a,b a Ins i u o In e uni e si a io de In es igación en Bioingenie ía y Tecnología O ien ada al Se Humano, Uni e si a Poli ècnica de València, I3BH/LabHuman, Camino de Ve a s/n, 46022 Valencia, España b Cibe , Fisiopa ología de Obesidad y Nu ición, CB06/03 Ins i u o de Salud Ca los III, Spain Abs ac . New elec oencephalog aphy (EEG) de ices, mo e po able and cheape , a e appea ing on he ma ke . S udying he eliabili y o hese EEG de ices o emo ional s udies would be in e es ing, as hese de ices could be mo e economical and compa ible wi h Vi ual Reali y (VR) se ings. The e o e, he aim in his wo k was o alida e a low-cos EEG de ice (Emo i Epoc) o moni o b ain ac i i y du ing a posi i e emo ional induc ion p ocedu e. Emo ional pic u es (IAPS) we e used o induce a posi i e mood in six een pa icipan s. Changes in he b ain ac i i y o subjec s we e compa ed be ween posi i e induc ion and neu al condi ions. Ob ained esul s we e in acco dance wi h p e ious scien i ic li e a u e ega ding on al EEG asymme y, which suppo s he possibili y o using his low-cos EEG de ice in u u e mood induc ion s udies combined wi h VR. Keywo ds. EEG, Emo i Epoc, Mood Induc ion, EEGLAB, IAPS In oduc ion In emo ional s udies, he on al elec oencephalog aphic (EEG) asymme y model s a es ha each hemisphe e is specialized in p ocessing di e en emo ions [1]. This model decla es ha he e exis s an asymme y in he ac i i y o he on al lobe o he b ain, and by means o his asymme ic ac i i y i is possible o mode a e and p ocess di e en emo ional esponses. Consequen ly, on al EEG asymme y can be e alua ed and applied o dis inguish he a ec i e alence o an emo ion el . Findings om nume ous s udies show an e iden consensus ha an inc ease o le on al ac i i y and a dec ease o igh on al ac i i y a e associa ed wi h posi i e emo ions, and ha an inc ease o igh on al ac i i y and a dec ease o le on al ac i i y a e associa ed wi h nega i e emo ions. This has o igina ed he app oach/wi hd awal model o Da idson [2-3] and is consis en wi h b ain inju y s udies. The esul s o p e ious s udies we e ob ained h ough EEG signal measu emen s, whe e he pa icipan s we e in a es momen . O he s s udies ha e complemen ed his in e p e a ion abou on al EEG asymme y du ing a mood induc ion p ocedu e. They ha e conside ed in e es ing o measu e he on al EEG signal in speci ic emo ional 1 Co esponding Au ho . Annual Re iew o Cybe he apy and Telemedicine 2013 B.K. Wiede hold and G. Ri a (Eds.) © 2013 In e ac i e Media Ins i u e 43 con ex s wi h he aim o analyzing he abili y o each indi idual o espond emo ionally [2-3]. I was obse ed ha on al EEG asymme y, du ing a ea induc ion, was a be e nega i e a ec p edic o han an analysis o EEG in a es condi ion. Howe e , he posi i e a ec could be p edic ed by EEG analysis bo h du ing a es condi ion and a posi i e induc ion momen . Clinical EEG de ices ha e been used in mos o hese s udies. The majo i y o hese sys ems a e e y p ecise bu hey ha e as disad an ages ha hey a e expensi e, in usi e and di icul o use by he he apis . Recen ly, he new low-cos EEG de ices, which a e appea ing on he ma ke , p o ide g ea po abili y and a good quali y b ain signal. Mo eo e , hese EEG de ices ha e a g ea compa ibili y wi h o he echnologies, such as Vi ual Reali y. Low-cos EEG de ices could be used in a Vi ual Reali y s udy wi hou in luencing he p og ess o his s udy. In he p esen wo k, he possibili ies o EEG moni o ing h ough a po able de ice o e alua e mood induc ion o pa icipan s we e analyzed. The e o e, he goal o his s udy was o analyze i a low-cos EEG de ice (speci ically, he Emo i EPOC) was able o measu e changes in b ain ac i a ion in he on al EEG while a posi i e mood was induc ed o he subjec s. 1. Ma e ials and Me hods Six een heal hy pa icipan s, 8 men and 8 women, we e e alua ed in his s udy, all o hem igh -handed and wi h ages be ween 23-30 yea s old wi h no mal o co ec ed- o- no mal ision. The subjec s we e uni e si y s uden s wi hou any psychological diso de and none o hem was an expe in he use o he echnologies applied in his s udy. They signed an in o med consen o allowing hei da a o be used in his s udy. I was no necessa y o exclude any pa icipan due o w ong egis a ion o he EEG signal. The EEG signal was moni o ed by means o an EEG po able de ice, Emo i EPOC [4] which had 14 EEG channels using he s anda d 10/20 layou and 2 e e ence channels (CMS/DRL), Fig 1. Figu e 1. Emo i EPOC de ice and Emo i EPOC elec odes posi ioning on s anda d 10/20 layou . A. Rod íguez e al. / Valida ion o a Low-Cos EEG De ice o Mood Induc ion S udies44 EEG eco dings we e analyzed o -line using cus om so wa e w i en in MATLAB. This cus om so wa e was based on EEGLAB [5] ools. Many EEG unc ions we e used o clean he EEG-da a and analyze changes in alpha-spec al powe . In he s udy, he pa icipan s had o wa ch posi i e and neu al pic u es o IAPS [6], which we e used as mood induc ion s imulus, in a desk op sc een. The expe imen al session was di ided in o ou s eps o wo minu es each. In he i s s ep, he pa icipan s had o wa ch a black sc een ( es s age). In he second s ep, he emo ional pic u es we e p esen ed (15 neu al pic u es). In he hi d s ep, ano he es s age was p esen ed. And in he las s ep, he o he emo ional pic u es we e p esen ed (15 posi i e pic u es). S eps numbe wo and ou we e coun e balanced. A wo way epea ed measu ed ANOVA was applied, being he independen ac o s he expe imen al momen , Neu al Condi ion e sus Posi i e Induc ion, and b ain hemisphe e ( igh /le ). Alpha-ERD (1) alues, calcula ed o F3 (le hemisphe e) and F4 ( igh hemisphe e) [2, 7, 8] senso s, we e used as dependen a iables. F3 and F4 we e used because hey a e he senso s mo e used in he scien i ic li e a u e o analyze he alence o he pa icipan s as hey a e loca ed abo e he do sola e al p e on al co ex [9]. (1) 2. Resul s Resul s showed signi ican di e ences be ween neu al and posi i e momen s (F(1,15)=5.859; p=0.029) and a signi ican in luence o he in e sec ion ac o be ween hemisphe e and momen (F(1,15)=9.594; p=0.007). Pai -wise compa isons only showed signi ican di e ences be ween hemisphe es du ing he posi i e induc ion (p=0.010). Table 1. Mean and s anda d de ia ion Alpha-ERD alues o he F3 and F4 senso s. Senso Neu al Condi ion Posi i e Induc ion Mean S d. Mean S d. F3 1.094 5.074 1.600 5.803 F4 0.386 4.545 -3.649 1.026 A dec ease was obse ed in he Alpha-ERD in he igh hemisphe e and an inc ease in he le hemisphe e when he posi i e emo ion was induc ed. Mean alues and s anda d de ia ion alues o each senso can be seen in he Table 1. Figu e 2 shows h ee opog aphic scalp maps, which gi e a isual ep esen a ion abou he dis ibu ion o a e age alpha ERD alues a ound scalp in he posi i e momen , he neu al momen and he di e ence be ween posi i e and neu al momen s, espec i ely. A. Rod íguez e al. / Valida ion o a Low-Cos EEG De ice o Mood Induc ion S udies 45 Figu e 2. Topog aphic scalp map o a e age alpha ERD alues. 3. Discussion The goal o his s udy was o analyze i a low-cos EEG de ice would be able o measu e changes in b ain ac i a ion in he on al EEG while a posi i e mood was induc ed o he subjec s h ough emo ional pic u es. S a is ical esul s show ac i a ion in he le hemisphe e signi ican ly g ea e han in he igh hemisphe e du ing he posi i e images isualiza ion. This ac i a ion was g ea e du ing posi i e induc ion han du ing neu al induc ion. In he igu e 2, he di e ence be ween alpha ERD alues o each momen can be seen. I shows ha he e is a igh hemisphe e deac i a ion and an inc ease in he le hemisphe e du ing he posi i e induc ion, in compa ison wi h he neu al induc ion momen . These esul s show e idence o a on al asymme y in he EEG o he pa icipan s du ing a posi i e induc ion, which is in acco dance wi h science li e a u e [1, 2, 8], ha a i ms ha ac i a ion o le hemisphe e is linked wi h posi i e emo ion induc ion [1, 2, 7, 8, 9]. This esul s suppo he possibili y o using he low-cos EEG de ices, in pa icula Emo i Epoc, as an emo ional measu ing ool in u u e s udies. Acknowledgmen s This s udy was unded by Vice ec o ado de In es igación de la Uni e si a Poli ècnica de València, Spain, PAID-06-2011, R.N. 1984; by Minis e io de Educación y Ciencia, Spain, P ojec Game Teen (TIN2010-20187) and pa ially by p ojec s Consolide -C (SEJ2006-14301/PSIC), “CIBER o Physiopa hology o Obesi y and Nu i ion, an ini ia i e o ISCIII” and Excellence Resea ch P og am PROMETEO (Gene ali a Valenciana. Conselle ía de Educación, 2008-157). The wo k o Alejand o Rod íguez was suppo ed by he Spanish MEC unde an FPI G an BES-2011-043316. Re e ences [1] Allen JJ, Coan JA, Naza ian M. Issues and assump ions on he oad om aw signals o me ics o on al EEG asymme y in emo ion. Biol Psychol 2004;67(1–2):183–218. [2] Coan, J. A., & Allen, J. J. (2004). F on al EEG asymme y as a mode a o and media o o emo ion. Biological psychology, 67(1), 7-50. A. 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